A self-servo reference signal including a timing pattern and an oblique phase pattern is transferred in advance on a magnetic disk 1 by magnetic printing. A phase difference detection section 13 detects a phase difference between the two patterns to detect the position of a magnetic head 2. A burst signal generated by a record signal generation section 14 is recorded in a region of the magnetic disk 1 where no self-servo reference signal is recorded. A track pitch calculation section 11 determines a relationship between the reproduction output of the burst signal detected by a reproduction signal processing section 12 and the phase difference detected by the phase difference detection section 13, thus calculating an optimum data track pitch.

(1) Field of the Invention
The present invention relates to a magnetic disk apparatus, a method for determining a data track pitch, and a self-servo write method.
(2) Description of the Prior Art
In recent years, magnetic disk apparatuses have been rapidly reduced in size and increased in capacity. For example, as for an increase in the capacity of magnetic disk apparatuses, the track density of disks is increasing, and track pitch is being further reduced. Therefore, in order to accurately record/reproduce data on/from a magnetic disk, it is necessary to precisely position a magnetic head at a target track among the tracks formed at a small pitch.
The position of a magnetic head is detected by allowing the magnetic head itself to read out servo signals recorded in advance on a magnetic disk at a certain angular spacing. The positioning of the magnetic head is controlled based on the servo signals. Specifically, from the detected magnetic head position information, a position error signal indicating the position error of the magnetic head with respect to the target track is generated, and the positioning of the magnetic head is controlled such that the magnitude of the position error signal is minimized. Accordingly, in order to position the magnetic head with high precision, servo signals serving as the reference for the positioning of the magnetic head must be precisely recorded on the magnetic disk.
Generally, methods for recording servo signals on a magnetic disk include: (1) a method for using a dedicated servo track recording device; (2) a method for performing magnetic printing method; and (3) a self-servo write method. Hereinafter, these methods will be briefly described.
According to the method for using a servo track recording device, in recording servo signals, while a magnetic head of a magnetic disk apparatus is precisely positioned by an external actuator provided in the servo track recording device, the servo signals are sequentially recorded using the magnetic head. However, the servo track recording device is expensive. Further, in order to record servo signals for a single magnetic disk apparatus, a period of time in the range of several tens of minutes to about one hour is required. Therefore, the expensive servo track recording device is exclusively used for a long period of time, and servo signals cannot be recorded on the other magnetic disk apparatus during that time. Thus, it is pointed out that the method for using a servo track recording device presents problems in terms of productivity and cost. Furthermore, since the magnetic head is positioned by the external actuator, a clean environment is required in order to avoid intrusion of dust into the magnetic disk apparatus.
According to the method for performing a magnetic printing method, a master disk, on which a pattern corresponding to servo signals is formed, is prepared, and the transfer recording of the servo signals is performed on a magnetic disk at once using the master disk. As such a method, for example, the following method is proposed: a master disk, on which a ferromagnetic thin film pattern corresponding to servo signals is formed, is brought into intimate contact with a magnetic disk, and an external magnetic field is applied, thus performing the transfer recording of the servo signals on the magnetic disk at once (see, for example, Japanese Patent No. 3323743). According to this method, the need for a servo track recording device is eliminated, and servo signals can be recorded with high precision for an extremely short period of time.
According to the self-servo write method, a reference signal, which is used as the reference, is recorded in advance on a part of a recording surface of a magnetic disk. Then, servo signals are sequentially recorded at a predetermined head-traveling pitch, while a magnetic head controls the positioning thereof by reading out the reference signal and detecting the position thereof. Although the self-servo write method has the advantage that no servo track recording device is required, it is pointed out that there are problems in how to record the reference signal, used as the reference for the positioning of the magnetic head, on the magnetic disk with high precision and at low cost. Therefore, in order to solve such problems, a self-servo write technique for recording a reference signal by the above-described magnetic printing method is proposed (see, for example, Japanese Unexamined Patent Publication No. 2001-243733).
However, in any of these methods, although servo signals are sequentially recorded at a predetermined head-traveling pitch, the head-traveling pitch during the recording of the servo signals is determined based on a data track pitch. In order to realize a highly reliable magnetic disk that enables accurate recording/reproduction of data, an optimum or suitable (hereinafter, simply called "optimum") data track pitch has to be determined, and servo signals need to be recorded at a predetermined head-traveling pitch calculated based on the data track pitch. An optimum data track pitch is determined based on various characteristics such as the gap lengths and characteristics of a reproducing element and a recording element of a magnetic head, the magnetic property of a magnetic disk, and a spacing between the magnetic head and the magnetic disk. Normally, these characteristics are varied for each magnetic head and each magnetic disk. Hereinafter, a method for calculating an optimum data track pitch will be described.
FIG. 6 is a diagram for describing a common method for calculating a data track pitch. The reference number 2 denotes a magnetic head, the reference number 2a denotes a recording element of the magnetic head, and the reference number 2b denotes a reproducing element of the magnetic head. The reference number 2c denotes a deviation (offset amount) of each of the gap centers of the recording element 2a and the reproducing element 2b. It should be noted that the gap lengths of the recording element 2a and the reproducing element 2b are individually different. In calculating a data track pitch, first, a burst signal 20 with a constant frequency is recorded using the recording element 2a. Next, the burst signal 20 is reproduced using the reproducing element 2b.
If the position of the magnetic head 2 is minutely changed with respect to the position of the magnetic head 2 when the burst signal 20 is recorded, the reproduction output of the burst signal 20 is changed. The relationship between the position of the magnetic head 2 and the reproduction output, which is plotted, is called an "off-track profile", and is represented by a curve 21. For example, the position of the magnetic head 2 corresponding to a half of the maximum value of the reproduction output is located at positions 21a and 21b, and a distance 22 between these positions 21a and 21b can be set as an optimum data track pitch. Furthermore, by measuring the distance between the position of the magnetic head 2 when the burst signal 20 is recorded, and that of the magnetic head 2 when the reproduction output is maximized, an offset amount 2c can be calculated.
A method for calculating an optimum data track pitch is not limited to the above-described method. As another method for calculating an optimum data track pitch, the following method is known: the relationship between an off-track allowance and a data track pitch is determined with respect to data signals recorded on a plurality of tracks at a predetermined data track pitch, and the data track pitch at which the off-track allowance is maximized is set as an optimum data track pitch (see, for example, R. A. Jensen, J. Mortelmans and R. Hauswizer, "Demonstration of 500 Megabits per Square Inch with Digital Magnetic Recording", IEEE Trans. Magn., vol. 26, No. 5, pp2169–2171 (1990), and description around column 4, line 22 of USP 06445521). An off-track allowance will be described later.
FIGS. 7A through 7D are diagrams for describing the method. According to the present method, the following steps (1) through (4) are carried out.
(1) As background noise, pre-data signals 30 are recorded on a magnetic disk (see FIG. 7A).
(2) The pre-data signals 30 are overwritten with data signals 31 at a predetermined data track pitch 32 (see FIG. 7B).
(3) The position of a magnetic head (not shown) is minutely changed, and then an off-track characteristic 33 with respect to the error rate of reproduction signals of the data signals 31 is determined (see FIG. 7C). Further, magnetic head positions 34a and 34b when the error rate reaches a predetermined value (BER0) are determined, and a distance 34c between the positions 34a and 34b is determined. This is an off-track allowance.
(4) The data track pitch 32 is changed, and then the steps (2) and (3) are repeated, thus determining the relationship between the data track pitch and the off-track allowance (see FIG. 7D). A curve 35 representing the relationship between the data track pitch and the off-track allowance is generally called a "747 curve". Based on the 747 curve 35, a data track pitch 32a at which the off-track allowance is maximized is determined, and this data track pitch 32a is set as an optimum data track pitch.
As apparent from the measurement of the 747 curve, there is a close relationship between the data track pitch and the error rate of the reproduction signals, and the error rate of the reproduction signals varies depending on how the data track pitch is set. Therefore, in order to reduce read error in regard to the reproduction signals so that the reliability of a magnetic disk apparatus is improved, it is important to calculate an optimum data track pitch.
As a technique for determining a head-traveling pitch during recording of servo signals by using a self-servo write method, the following technique has already been proposed: a magnetic head is positioned using a reference signal recorded on a recording surface of a magnetic disk, and the above-mentioned off-track profile, for example, is determined to calculate an optimum head-traveling pitch. For example, in the proposed technique, the reference signal, which is used as the reference, is recorded in advance on a part of the recording surface of the magnetic disk, and the reference signal is read out by the magnetic head, thus determining the off-track profile (see, for example, Japanese Patent No. 3251804).
On the other hand, a technique for determining an off-track profile without using a reference signal is also proposed (see, for example, Japanese Unexamined Patent Publication No. 2002-230929). According to this technique, an actuator that supports a magnetic head is pressed against an elastic stopper provided in a magnetic disk apparatus, and an off-track profile is determined from the relationship between electric current for driving the actuator and reproduction output.
In the method for calculating an optimum data track pitch using an off-track profile and/or a 747 curve, for example, it is necessary to position a magnetic head with high precision and then to determine the reproduction output and/or error rate of signals.
In the method for recording servo signals using a dedicated servo track recording device, a magnetic head can be precisely positioned by using an external actuator. Since an off-track profile and/or a 747 curve are/is determined after the precise positioning of the magnetic head, the accurate calculation of an optimum data track pitch is theoretically possible. However, in recording servo signals, in addition to the step of recording servo signals themselves, the step of calculating a data track pitch is required. Therefore, a period of time during which the servo track recording device is exclusively used for a single magnetic disk apparatus is further extended, which might cause a further reduction in productivity. Accordingly, the fact is that at a site where magnetic disk apparatuses are mass-produced, an optimum data track pitch is not calculated for each magnetic disk apparatus, but a specific track pitch, determined averagely by considering variations in sizes and/or characteristics of recording and reproducing elements of the magnetic head, is uniformly set as an optimum data track pitch. Thus, if variations in various characteristics, such as the size and/or characteristic of each element of a magnetic head, the magnetic property of a magnetic disk, and a spacing between the magnetic head and the magnetic disk, are great, the resulting magnetic disk apparatus cannot achieve a desired performance, and the yield is reduced.
On the other hand, in the conventional technique for recording servo signals using a self-servo write method, it is difficult to say that the accuracy in calculating an optimum data track pitch is sufficiently high.
According to the technique disclosed in Japanese Patent No. 3251804, provisional servo information is recorded in advance on a part of a magnetic disk, and servo information is recorded using the provisional servo information. In order to calculate an optimum data track pitch with high accuracy, it is important to increase the accuracy of the provisional servo information that is recorded in advance. Therefore, in the technique disclosed in the above publication, the provisional servo information is recorded using a dedicated external device. However, since the dedicated external device is used, the advantage of the self-servo write method itself is reduced. Furthermore, since the provisional servo information is recorded only in a part of a recording region, the calculation of an optimum data track pitch is effective only for the recording region of the provisional servo information, and a data track pitch different from the optimum data track pitch is undesirably set for the other recording region.
According to the technique disclosed in Japanese Unexamined Patent Publication No. 2002-230929, a reference signal is not used, but an elastic stopper is utilized; however, in calculating a data track pitch, the deformation property of the elastic stopper becomes an error factor, and thus the data track pitch cannot be accurately calculated.
In a normal magnetic disk apparatus, a magnetic head is rotated around a rotation bearing (pivot) by a voice coil motor (VCM), and is moved from the outer radius of a magnetic disk to the inner radius of the magnetic disk (or from the inner radius to the outer radius). That is, the magnetic head can be moved substantially in a radial direction of the magnetic disk. However, since the magnetic head is rotated around the rotation bearing, the longitudinal direction of the head does not necessarily correspond to the radial direction of the magnetic disk, and a skew angle exists depending on the radial position of a recording track. FIGS. 8A and 8B are schematic diagrams illustrating the positional relationship among the recording element 2a, the reproducing element 2b and a recording track 41 in the case where no skew angle exists and in the case where a skew angle exists, respectively. As can be seen from FIGS. 8A and 8B, the projected length of the magnetic head in the radial direction, i.e., a substantial recording element width 2d, varies between the case where no skew angle exists (see FIG. 8A) and the case where a skew angle exists (see FIG. 8B). Besides, the substantial recording element width 2d also varies depending on the magnitude of the skew angle. Therefore, an optimum data track pitch 40 varies for each recording track position.
Thus, in a magnetic disk apparatus, an optimum data track pitch varies depending on the recording track position (radial position) of a magnetic disk. However, any of the above-described methods cannot cope with a variation in the optimum data track pitch due to the track position.

Magnetic disk apparatus, method for determining data track pitch, and self-servo write method

Matsushita Electric Industrial Co., Ltd.


The present invention provides a time tracking device comprising a display incorporated into a housing of a projector, a control pad, and a power source. The time tracking device can provide a presenter with the ability to track the elapsed time of a presentation. The time tracking device is further capable of being projected onto a viewing screen using the light source and lens of the projector device. The device comprises a control pad which controls the functions of the timer device, such as on/off, start, stop, pause, reset, mode, illumination, and time of day. The present invention also provides a presentation timer comprising a presentation timer program module and an input control module operable for controlling timer functions associated with the presentation timer program module.

There are many conventional devices used for displaying information to an audience. Examples of an audience may include a group of students seated in a classroom, a group of business people at a conference, and participants connected to a conference via video conferencing equipment. Information presented to the students and other audiences, perhaps by a professor or a guest speaker, may be presented using a projector, such as an overhead projector or a slide projector. Information presented to an audience may also be presented using a personal computer, such as a laptop computer connected to a display projection device.
Conventional timing devices, such as clocks and stopwatches, are well known. In a typical classroom environment, there is typically a clock located on one of the classroom walls that displays the time of day. However, the clock typically does not possess stopwatch-type functions, and may not be in the same line of sight as the projector screen, making it inconvenient to look at the clock while maintaining focus on the subject matter of the presentation. Also, a presenter is not able to control the timing functions of a wall clock. There may be occasions during a presentation when it would be desirable for a speaker to have control of timing functions, such as during an experiment, an exam, or in tracking the total elapsed time of a presentation.
Video conferencing is typically a costly service. Displaying a timer to each conference participant would aid in the tracking of the total time of the video conference so as to make participants aware of the cost of the conference. Displaying the elapsed time of a video conference to all participants also aids in reminding the participants of how long they have been involved in a conference, in case they have a schedule to maintain. Since participants may become very involved in a conference and may lose track of the time, displaying the time to each participant on their individual screen is an effective way of providing a constant reminder.
A conventional time tracking approach is provided in U.S. Pat. No. 5,590,944, in which a portable electronic device having a transparent liquid crystal display is described. The timing device includes a plastic casing, foldable legs, and is placed onto the surface of a projector where light passes through the device and displays LCD numerals onto a screen. A disadvantage of the timer of the '944 patent is that it is not connected to a projector and may be easily lost, separated, or dropped from the projector surface. Since the device of the '944 patent is not integrated into the projector, it must also be supplied as a separate piece of equipment. Another disadvantage of the '944 timer is that it must be placed onto a flat, horizontal surface, such as that of an overhead projector. Many conventional projectors, such as a slide projector, do not possess a flat horizontal surface, making the conventional timer of the '944 patent impossible to use. An additional disadvantage of the '944 timer is that it interferes with the working space of an overhead projector surface, making it troublesome for a presenter to switch transparencies on the overhead projector without knocking the '944 timer out of place or even off of the projector surface onto the floor, where it may be become damaged.
A second timer approach is provided in U.S. Pat. No. 5,905,694, in which a timing device for coordinating a presentation includes a master timer with a timing initiator, a programmable master sensory alarm responsive to the sequencer, a master alarm silencer, and a communication transmitter responsive to at least one of the timing initiator and the master sequencer. The device of the '694 patent involves a low power radio signal transmitted by the communication transmitter. The timing device of the '694 patent is used for coordinating the timing of a presentation, but does not include a time display that may be displayed to the audience. The device involves sending a signal from a master controller to a slave timer that alerts a speaker of a time limit.
It is further desirable to have a device that allows a presenter of an audio/visual presentation to track the elapsed time of a presentation. It is also desirable to provide a time tracking device in which the presenter can start, stop, and pause the time tracking device in a simple manner, without taking time away from a presentation. Preferably, such a device would be included within a projector device, thus eliminating the need for a presenter to supply such a device for a presentation. It is also preferable that the time displayed on the timing device be capable of being projected by a projector to the viewing audience in an easy to read and interference free manner.

Timer device for use in an audio/visual presentation


A polarizer includes a first grating and a second grating. The second grating contains at least one of chromium nitride, tungsten nitride, and tantalum nitride.

1. Technical Field
The present invention relates to polarizers, methods of production thereof, projectors, liquid crystal devices, and electronic devices.
2. Related Art
Wire grid polarizers are known as a type of polarizer. The wire grid polarizer is configured to include a metallic grid overlaid on a transparent substrate in a pitch shorter than the wavelengths of the light used. Because the wire grid polarizer can be realized using only inorganic materials, deterioration due to photoirradiation occurs much less frequently than in polarizing plates that use organic materials. The wire grid polarizer has thus attracted interest as an effective device in liquid crystal projectors of ever increasing brightness.
Despite the excellent heat resistance of the wire grid polarizer, there is a demand for improved high-temperature reliability in the face of the increasing brightness of liquid crystal projectors.
JP-A-2005-37900 discloses that a polarizer having high contrast and excellent light use efficiency can be provided by lamination of a high-reflection grating layer and a high-absorption grating layer on a substrate. The photoabsorptive thin film disclosed in this publication uses high-melting-point materials such as tungsten, chromium, and molybdenum. However, oxidation resistance is poor, and the film is not suited for actual use in a high-temperature environment of 300° C. or higher.
JP-A-2009-186929 describes using carbon, carbides, oxides, sulfides, or nitrides as the preferred light use efficiency light absorbing material in terms of improving photoabsorbability. Specifically, a polarizer is disclosed in which aluminum oxide, iron oxide, nickel oxide, copper oxide, vanadium oxide, and chromium oxide are used as light absorbing materials. Metal oxides are among the materials having the highest oxidation resistance under a high-temperature environment. However, the attenuation coefficients k of the metal oxides described in the examples of JP-A-2009-186929 are very small in the visible range, and are not suited for practical applications. The attenuation coefficient k is the imaginary part of the complex refractive index N=n+ik. Other than oxides, the publication discloses carbides, sulfides, and nitrides as examples of the light absorbing material. However, a specific composition is not disclosed, and the publication is silent as to the optical absorption characteristics of these materials, and the oxidation resistance in a high-temperature environment.

Polarizer, polarizer producing process, projector, liquid crystal device, and electronic device


An automotive air blower, in particular a supercharger, comprises an air pump, such as an air impeller (2) connected to the output shaft (4) of a transmission system, the input shaft of which is connected, in use, to the engine of a motor vehicle. The input and output shafts (6, 4) are connected to respective branches of a three-branch epicyclic differential gearset. The third branch of the gearset and the input shaft (6) are connected to the rotor (20, 22) of respective electrical machines, the electrical connections of the stators (24, 26) of which machines are connected together via a controller (27) arranged to control the flow of electric power between them.

The present invention refers to automotive air blowers and, in particular to automotive superchargers, which are devices which may be incorporated in automotive engines. Superchargers are devices that include an air pump or blower wheel, rotation of which changes the pressure conditions in the inlet system of the engine, the inlet pressure. Commonly the device is configured and operated in a way that increases the inlet pressure and therefore enables the power output of the engine to be increased. Alternatively the device may be configured to lower the Inlet Pressure and reduce the power output, this method of power control offering efficiency advantages when compared with the conventional method of load control through a throttle valve.
An air blower in accordance with the invention may, however, also take other forms, such as an automotive cooling fan for blowing air over a cooling radiator.


A tailgate cover for a pickup truck consists of a flap running along the tailgate gap and hingedly connected to the end of the bed. When the tailgate is open, the flap has one edge flush with the end of the bed and the other edge overlapping the bottom of the gate. When the gate is closed, the flap is rotated around its hinges such that the edge overlapping the gate is pushed upward and the edge facing the bed is correspondingly flipped downward within the gap. As a result of this configuration, the flap covers the tailgate gap at all times and produces a level surface with the truck bed when the gate is lowered.

1. Field of the Invention
This invention is related in general to the field of automotive accessories and, in particular, to a device for covering the gap formed between the tailgate and the bed of a pick-up truck.
2. Description of the Related Art
Typically, pick-up trucks have a tailgate hingedly attached to the rear end of the bed, such that it can be swung open to allow loading and unloading or to extend the bed's surface. Because the bed and the tailgate are two separate structural units connected only at the hinge points, a gap is necessarily present between their abutting surfaces at the bottom of the gate. Thus, sand, gravel and other loose material that is often carried in pick-up trucks tends to fall in the gap and be lost or interfere with the operation of the tailgate and hinge mechanisms, and cause wear between the tailgate and bed end. The problem is normally exacerbated when the tailgate is open because most hinge mechanisms tend to widen the gap as the tailgate is lowered. While a gap of about 12 mm is typical when the tailgate is closed, it is not unusual for the gap to widen to about 50 mm when the tailgate is opened flat as an extension of the bed. Since loose material carried in the bed is often unloaded by pushing it over the open tailgate, the gap is filled with smaller particles during unloading, which at times makes it impossible to close the tailgate thereafter without first removing it from its hinges to free the particles.
A variety of tailgate gap covers have been described in prior-art patents. For example, U.S. Pat. No. Des. 374,854 (1996), issued to Little et al., shows a tailgate gap cover consisting of a plank with beveled edges suitable for covering the length of the gap. A retaining member is provided for installing the cover by inserting it within the gap when the tailgate is open. The device must be installed for use each time after opening the gate and does not prevent material from falling into the gap when the gate is closed.
Murray, in U.S. Pat. No. 4,763,945 (1988), describes a foldable tailgate track mat that covers the gap and provides a conforming connection as the gate is opened and closed. The mat consists of a resilient strip permanently mounted on the tailgate and slidably connected to the bed to account for the gap expansion when the gate is opened.
Finally, U.S. Pat. No. 5,664,822, issued to Rosenfield (1997), describes other resilient covers for the tailgate gap of different pickup trucks. Each cover consists of a strip attached to both the bed and the gate and features strategically-placed folding joints to accommodate the difference in gap size between open and closed conditions.
None of the devices described in the foregoing patents provides a level and smooth connection between the bed and the tailgate of a conventional truck. In addition, none is suitable for integral implementation with the hinge mechanism of the tailgate. Therefore, there still exists a need for a simple device of universal application that covers the gap between the bed and tailgate of pickup trucks and provides a uniform level surface between them.


Compensation of effects derived from bandwidth limitations of an active frequency-selective circuit is effected by appropriately coupling a resistance to the frequency-selective circuit. In one embodiment, the resistance is designed to have a value that is inversely related to the tangent of a phase-shift at a compensation frequency.

Operational transconductance amplifiers (OTAs) are commonly used to realize certain passive components, e.g., inductors, in integrated circuit devices. In one implementation, cross-coupled OTAs are configured to constitute a gyrator. As a result of gyrator operation, a capacitance coupled across an output port of the gyrator is reflected as an inductance across the gyrator input port. The magnitude of the reflected inductance is proportional to the capacitance of the capacitor and is inversely proportional to the square of the transconductance of the OTAs that constitute the gyrator. In general, this technique is effective to instantiate components, such as inductors, that are not easily implemented through conventional integrated circuit fabrication techniques. Additionally, OTA implementation enables frequency-selective passive components (e.g., integrated inductors) to be electronically tuned by controlling the transconductance of the gyrator OTAs
However, the finite bandwidth of the gyrator OTAs is manifest as a transconductance that is a function of the frequency of operation. That is, the OTA transconductance (Gm) is bandwidth limited in a manner that is defined by the cutoff frequency of the OTA. Consequently, when the gyrator-synthesized inductance is incorporated into a filter circuit, the frequency-dependent transconductance of the gyrator causes spurious peaks in the filter passband, and causes degradation in the stopband attenuation. Conventional approaches to the remediation of these anomalies have been predominately directed to increasing the bandwidth of the gyrator OTAs. However, only limited success is achievable in this manner, in large part because OTAs with the requisite bandwidth are difficult to design and implement. Consider, for example, an active bandpass filter designed to have a cutoff frequency at 80 MHz. Simulation results suggest that in order to suppress passband peaks in the transfer function of such an OTA-implemented filter to less than 0.2 db, for example, an OTA bandwidth of 8 GHz may be required. That is to say, in such applications the OTA bandwidth is preferably at least 100 times the filter cutoff frequency. Attempts to extend the bandwidth of the OTAs to such a frequency may be confronted by the limitations of state-of-the-art semiconductor device fabrication techniques. In addition, extremely high bandwidth may sometimes be had only at the risk of instability.
Accordingly, what is desired is a technique that mitigates anomalies in the frequency-dependent characteristics of integrated circuit components that are predicated on finite-bandwidth OTAs. In particular, it is desired that there be provided a technique to minimize spurious peaks, or ripples, in the passband of Gm-C filters.


A method for manufacturing a probe card includes a first contact formation step of forming a first contact on a first surface of a first sacrificial substrate, a second contact formation step of forming a second contact on a first surface of a second sacrificial substrate, a signal transmission line formation step of forming a signal transmission line in the base substrate, a first contact joining step of attaching the first surface of the first sacrificial substrate to the base substrate and joining the first contact to the signal transmission line, and a second contact joining step of attaching the first surface of the second sacrificial substrate to the base substrate and joining the second contact to the signal transmission line.

1. Field of the Invention
The present invention relates to a method for manufacturing a probe card.
2. Related Art
In the recent trend of making the pitch of electrodes of an electronic device narrow, a demand for miniaturizing the probe pins of a probe card provided in a testing apparatus for testing the electronic device with high precision has also been increasing. As conventional minute probe pins, the membrane type probe pins are known.
The membrane type probe pins, however, have a problem that they are liable to be deformed because of being in contact with the electronic device. Accordingly, it is difficult to provide a probe card having minute probe pins with high precision.


High-purity nitrogen gas is generated by reducing at least the residual oxygen content of at least the cathode exhaust gas stream of a fuel cell device. The oxygen reduction is achieved either by controlling the passage of an oxidant gas through the cathode side of the fuel cell device in such a manner as to increase the oxygen utilization at the cathode side of the fuel cell device relative to the optimum electric power generation operating conditions of the fuel cell device, or by removing most of the residual oxygen from the cathode exhaust gas stream exhausted from the cathode side of the fuel cell device, while maintaining both oxygen and nitrogen contained in the cathode exhaust gas in their gaseous states throughout, or both. Moreover, anode exhaust gas can be reacted in a reformer burner with a reduced amount of excess oxygen and/or the reformer burner exhaust gas can be purified to remove combustion products and/or oxygen therefrom.

Nitrogen is one of the most important industrial gases in the world, second only to oxygen in use. At the present time, nitrogen is generally delivered to the user as substantially pure nitrogen in bulk liquid form. A method that is currently most frequently used for the production of such substantially pure nitrogen is by air liquefaction and fractionation. While this method has the advantage of also simultaneously resulting in the production of high-purity oxygen, it nevertheless has the pronounced disadvantage that it is expensive to perform and energy intensive. Therefore, the cost associated with this method is justifiable only under certain circumstances, such as when is it mandatory that the nitrogen that is to be used in a particular application be substantially pure, when the only practical way of delivering nitrogen from the production facility to the location of use is in its liquid bulk form, and/or when there is a demand for the oxygen that is simultaneously obtained in this operation.
It was already previously attempted to obtain high-purity or even substantially pure nitrogen in various ways other than ambient air liquefaction and fractionation. Thus, for instance, it has been realized that a hydrocarbon air fuel cell device produces a relatively clean nitrogen rich exhaust product. Based on this recognition, it was proposed in commonly assigned U.S. Pat. Nos. 4,767,606 and 4,792,502 to Trocciola et al to combine a fuel cell device of this type with a cryogenic liquefaction and fractionation apparatus in such a manner that such apparatus converts the fuel cell cathode exhaust gas, which contains nitrogen, oxygen and water vapor, into a substantially pure nitrogen product. However, even this process is too expensive, despite the fact that the cathode exhaust gas contains a much lower percentage of oxygen than ambient air, unless the above conditions are present.
On the other hand, it is known from a commonly assigned U.S. Pat. No. 4,751,151 to Healy et al to employ a carbon dioxide absorber in a fuel cell system to recover carbon dioxide from the fuel cell anode exhaust stream (fuel gas) containing principally hydrogen, carbon dioxide, carbon monoxide, and water vapor. However, even this process would be rather uneconomical if it were attempted to use the thus constructed system with a hydrocarbon air fuel cell device, especially since the anode exhaust stream carries only about 20% of the nitrogen passing through such fuel cell device.
Moreover, there are already known various constructions of gas purifying devices, among them such using polymer membranes and the pressure swing absorption approach, for removing unwanted gaseous ingredients from gases, such as oxygen from air, to obtain high-quality nitrogen product. However, even these processes as previously applied to the production of nitrogen from air leave much to be desired in terms of economy of operation and thus cost of the thus obtained high-purity nitrogen.
Accordingly, it is a general object of the present invention to avoid the disadvantages of the prior art.
More particularly, it is an object of the present invention to provide a method of producing high-purity nitrogen gas, which method does not possess the disadvantages of the known methods of this kind.
Still another object of the present invention is so to develop the method of the type here under consideration as to reduce the cost of the high-purity nitrogen obtained by using this method.
It is yet another object of the present invention to devise an apparatus which is suitable for the performance of the method of the above type.
A concomitant object of the present invention is design the apparatus of the above type in such a manner as to be relatively simple in construction, inexpensive to manufacture, easy to use, and yet reliable in operation.

Method of generating high-purity nitrogen gas


A staking nut and a grounding clamp with the staking nut are disclosed in which the clamp includes a flexible metal strap with openings through the ends of the strap. Threaded studs extend through the openings at one end of the strap to firmly attach the lug of a grounding conductor to the strap. The staking nuts are provided through the openings at the other end of the strap to prevent removal of the nuts from the strap, but permit rotation so that the nuts while held captive to the strap may be threaded upon the threaded studs to clamp the grounding clamp to a coaxial cable which is to be grounded.

The present invention relates to a staking nut, and more particularly, to a cable grounding clamp having the staking nuts captive thereon for achieving the clamping function.
Grounding clamps for cables, such as coaxial cables on wireless telephone communication towers, have been employed in the past to ground the cables to protect against damage from lightning strikes. In use the outermost insulative jacket of the coaxial cable to be grounded is stripped where the clamp is to be applied. This will expose a conductive sheath of the cable beneath the jacket. A conductive copper strap is bent around the conductive sheath, and the strap is then clamped around the conductive sheath by applying individual lock washers over threaded rivet studs and threading conventional nuts on the studs to tighten the strap clamp in electrically conductive relationship to the coaxial cable sheath. In turn, the threaded rivet studs also act to rivet the lug of the grounding conductor to the strap clamp.
Such prior grounding clamps suffer several disadvantages. One disadvantage is the difficulty of installation due to the number of distinct individual pieces that must be manipulated to complete the clamping procedure. This is particularly a problem in such grounding clamps when it is considered that they are applied to coaxial cables at considerable altitudes above the ground by personnel who are suspended at that altitude during the application of the grounding clamps. Due to the multiple individual parts and the small size of some of their components such as the nuts and lock washers, the possibility exists that while the nuts are tightened, the nuts and lock washers may be dropped and lost.
The present invention overcomes these disadvantages in a simple and inexpensive manner. In the present invention the nuts which are utilized to achieve the clamping function are captive to the strap itself, but still capable of rotation relative to the fixed threaded studs or rivets to complete the clamping function. Moreover, the need for lock washers is obviated. Because the nuts are captive to the strap, they are easier to handle during installation and not subject to being dropped and lost during that procedure.
In one principal aspect of the present invention, a staking nut comprises a block portion having a face, and at least one surface adapted to be engaged by a tool to rotate the block portion. A passage extends into the block portion from the face, and the passage is threaded to receive a threaded stud therein. A substantially cylindrical staking shaft is on the block portion and extends from the face. The staking shaft has a given external cross-sectional dimension and also includes a passage which is coaxial with the passage of the block portion, with the staking shaft passage having a minimum cross-sectional dimension which is at least as large as the maximum cross-sectional dimension of the passage in the block portion. The staking shaft is formed of a material which is capable of expansion to an external cross-sectional dimension which is greater than the given external cross-sectional dimension.
In another principal aspect of the present invention, the block portion and staking shaft are formed in integral one piece relationship to each other.
In still another principal aspect of the present invention, the block portion and staking shaft are formed of the same material.
In still another principal aspect of the present invention, the material of the staking shaft is deformable to produce the expansion.
In still another principal aspect of the present invention, a grounding clamp comprises a flexible elongate metal strap having first and second ends; an elongate threaded stud at the first end of the strap; and a nut at the second end of the strap. The nut has a threaded passage therein aligned to threadedly receive the threaded stud into the threaded passage of the nut to attach the first and second ends together. A coupling couples the nut to the second end of the strap to prevent removal of the nut from the second end of the strap, but permit rotation of the nut relative to the stud while the nut is coupled to the second end to thread the nut onto the threaded stud.
In still another principal aspect of the present invention, the stud is non-rotatably fixed to the first end of the strap.
In still another principal aspect of the present invention, the aforementioned grounding clamp includes a conductor with a lug thereon, and the stud comprises a rivet which mounts the lug to the first end of the strap.
In still another principal aspect of the present invention, the strap has at least one opening through the strap adjacent the second end, and the nut and coupling comprise the aforementioned staking nut which is captive in the opening.
These and other objects, features and advantages of the present invention will be more clearly understood through a consideration of the following detailed description.


An electronic apparatus includes a housing, first and second circuit boards disposed in the housing in such a way that the first and second circuit boards are stacked on each other, and a pump block disposed between the first and second circuit boards, the pump block abutting a first electronic part mounted on the first circuit board and a second electronic part mounted on the second circuit board, the pump block sucking air outside the housing and discharging the air out of the housing.

1. Filed of the Invention
The present invention relates to an electronic apparatus, such as a video camera, a digital camera, a mobile phone, and a PDA.
2. Description of the Related Art
There are electronic apparatus in which electronic parts, such as ICs made of semiconductor, can be cooled. There are, for example, a method for diffusing heat generated in electronic parts in an entire apparatus using a heat sink, a heat pipe, a copper plate, and other components having heat dissipating fins, and dissipating the heat from the surface of a housing, and a method for performing forced-air cooling by distributing a cooling air flow to heat dissipating fins using an axial-flow fan or other fans (JP-A-2003-283171, for example).


The present invention relates to light weight molded plastic articles and methods of making same. More specifically, the present invention relates to a method of manufacturing a hollow-core, foamed-plastic, film-laminate article utilizing convention gas assisted molding apparatus with corresponding high production rate capabilities. The resulting film-laminate, hollow-core, foamed-plastic part comprises a class A show-face surface. The method comprises formation of a porous mass of molten plastic in the mold cavity containing the laminate. The molten plastic is cored out or hollowed by injection of gas into the mold cavity.

Utilization of thermoplastics in the manufacture of various molded articles is well known and widely exploited. Recent efforts to minimize part weight and reduce the amount of polymer required for a given piece have gained a great deal of attention. Generally, two approaches for reducing weight and material have evolved; first, use of a pressurized gas to "core-out" the center portion of the given piece; second, use of a nucleating agent and, or blowing agent, to induce foaming of the polymer. The hollow core and void areas of the foamed-plastic displace polymer material, thereby, creating a part equivalent in exterior dimension to a given solid plastic part using less polymer. An ancillary benefit of using foamed-plastic and hollow cores is that larger dimensioned molded articles can be manufactured with less sink marks and related surface deformations.
Foamed polymeric materials are well known, and typically are produced by introducing a physical blowing agent into a molten polymeric stream, mixing the blowing agent with the polymer and shaping the mixture with an extrusion die or closed mold. Exposure to atmospheric, or reduced pressure conditions causes the blowing agent to gasify, thereby forming cells in the polymer. Under controlled conditions the cells can be made to remain isolated and a closed-cell foamed material results. Under other, typically more violent foaming conditions, usually associated with less complex and less expensive molding processes, the cells rupture or become interconnected and an open-cell material results. As an alternative to a physical blowing agent, a chemical blowing agent can be used which undergoes chemical decomposition in the polymer material causing formation of a gas.
Use of uniform, microcellular, foamed-plastic results in molded parts with more visually pleasing surface finish than does an open cell foamed-plastic. However, non-conventional, more expensive, complex molding equipment and related processes are required to produce uniform, microcellular, foamed-plastics.
U.S. Pat. No. 6,169,122 B1, to Blizard et al., the disclosure of which is incorporated herein by reference thereto, discloses a method of producing articles of foamed-plastic wherein the foamed-plastic is formulated in such a way as to induce a uniform density of microcellular voids. The Blizard et al. disclosure discusses in length the various approaches taken in an effort to produce a foamed-plastic article with acceptable surface characteristics. Blizard et al. combines a chemical blowing agent and physical blowing agent to produce a foamed-plastic which exhibits uniform, microcellular, characteristics. The associated molding apparatus is non-conventional, expensive and complex.
The process of hollowing out the core may be used to provide the above benefits. However it may lead to the production of undesirable visual surface characteristics. U.S. Pat. No. 5,639,405, to Erikson, the disclosure of which is incorporated herein by reference thereto, provides an enlightened discussion of various apparatus for molding a hollow core plastic article. As disclosed in Erikson, a great deal of complexity is added to the related molding equipment in an effort to time the injection of molten plastic with the injection of gas. In the method of Erikson, supra, the timing of injecting gas with respect to injection of molten plastic is critical with regard to minimizing the resulting undesirable surface effects and maximizing resulting part integrity. The molding equipment used in Erikson employs a host of sensors and a corresponding control system to automatically adjust the injection timing.
Many of the molded plastic parts resulting from known manufacturing processes which incorporate coring and foaming steps have not yet achieved show-face characteristics with corresponding production rates acceptable for producing automotive products. Oftentimes, known coring operations with acceptable production rates induce swirling, inconsistent, patterns on the exterior surfaces of the corresponding parts and are sometimes susceptible to leaving cellular void areas on the corresponding part surfaces.
Therefore, there remains a need in the art for an economically viable method of manufacturing a light weight molded plastic part with a class A show-face surface while obtaining an acceptably high production rate. A further desire is to retain use of conventional molding equipment without added complex, expensive, systems.

Light weight plastic trim parts and methods of making same


An assembly including a tray-like member having a multiplicity of parallel adjacent elongate troughs. Each of the troughs has a major portion adjacent a first edge, and a minor portion adjacent a second edge; and the assembly includes a transparent polymeric sheet sealed over the minor portions of the troughs to define receptacles for liquid. After the major portions of the troughs are positioned beneath the spray zone at a specific distance from the nozzles with the troughs extending transverse of the elongate spray zone and after liquid is sprayed through the spray nozzles upon its upper surface, the assembly can be tipped so that the liquid collected in the troughs will run into the receptacles and the comparative resultant levels of liquid the receptacles will provide a visual indication of the uniformity of the amount of liquid being delivered by the nozzles along the spray zone at the specific distance.

Assemblies for use in determining the relative rate of delivery of a liquid sprayed through spray nozzles along an elongate spray zone at a specific distance from the spray nozzles are known. U.S. Pat. No. 4,539,842 and German Utility Model No. 6804628 provide examples. The assembly described in U.S. Pat. No. 4,539,842 includes a tray-like member having evenly spaced alternating first ridge portions and recessed portions defining along its upper surface a multiplicity of parallel adjacent elongate troughs extending from one edge, and an end ridge portion transverse of the troughs along that first edge that provides and end wall for the troughs. The tray like member is adapted to receive removable collector test tubes longitudinally aligned with ends of the troughs opposite its first end ridge, and is mounted on a height adjustable cart so that troughs can be positioned beneath an elongate spray zone at a specific distance from nozzles producing the spray zone with the troughs extending transverse of the elongate spray zone. After liquid is sprayed through the spray nozzles upon the upper surface, the assembly can be tipped so that the liquid collected in the troughs will run along the troughs into the test tubes and the comparative resultant levels of liquid the test tubes will provide a visual indication of the uniformity of the amount of liquid being delivered by the nozzles along the spray zone at the specific distance. While the assembly described in U.S. Pat. No. 4,539,842 should be effective in providing a visual indication of the uniformity of the amount of liquid being delivered by nozzles along a spray zone at specific distances from the nozzles, it has a large, complex and expensive structure so that some persons that might benefit from using it may not do so because of its expense, and/or because of the inconvenience of transporting and storing it between uses.


An automatic gain control RF signal processor for receiver systems, such as radar intercept receivers, includes an attenuator having an input for receiving an analog RF input signal, an amplifier coupled to the attenuator, a bandpass filter coupled to the amplifier output, a single ADC coupled to the bandpass filter, a digital logic circuit, and a FIFO buffer. The digital logic circuit has an input for receiving the ADC output signal, a first output coupled to a variable gain control input of the attenuator, and a second output. The logic circuit includes signal detection logic for detecting the presence of a pulse within the ADC signal, determining a peak amplitude value of the pulse, and based on the peak amplitude value generating an attenuation value at the first output that is applied to the variable gain control input of the attenuator. The sampling logic averages a number of ADC data samples to determine a moving average pulse amplitude, and compares this moving average pulse amplitude to a processing threshold value to determine a delta value with which to adjust an attenuation value for the attenuator, and to determine when to terminate a pulse and reset the attenuation value to zero. The averaging is carried out to determine whether an assigned number m of n samples is above the processing threshold value or whether the pulse should be terminated.

RF signal processors typically require automatic gain control (AGC) in order to detect and process RF signals that may vary over a wide range of signal strength. Radar and communications receiver systems generally include (1) an antenna, either directional or omnidirectional, (2) a superheterodyne receiver for tuning to a specific RF and converting to an intermediate frequency (IF), (3) a processor for detecting IF signals and for extracting information from these, and (4) a graphical user interface.
Regarding (3), the IF signal detecting and processing component, historically the IF signal has been processed by a combination of analog and digital components. However, recent advancements in technology have allowed direct digitizing of the IF signal using an analog to digital converter (ADC), resulting in a simpler system architecture that may be termed "Direct Digitization Technology" (DDT) which eliminates the bulky and expensive analog components. For example, U.S. Pat. No. 5,161,170 describes a pulse-to-pulse AGC circuit for digital radar intercept receivers. The system, however, includes certain analog components, e.g. a logarithmic amplifier/detector and a track/hold device, and has the above-noted disadvantages regarding such analog-based designs.
Although DDT reduces system size and cost, typical RF receivers have dynamic ranges in excess of 60 dB, whereas currently available ADCs have usable dynamic ranges of 25 to 45 dB. Therefore, it is desirable to include an automatic gain control (AGC) circuit in front of the ADC to continuously adjust the signal level to be within the dynamic range of the ADC.
U.S. Pat. No. 5,276,685 shows an example of a digital design that implements AGC in a digital quadrature RF receiver. Although the system utilizes digital instead of analog components, these are selected for implementation in a personal communications system (PCS) receiver and are not optimized or well-suited for detecting and processing radar signals.
Another digital system described in U.S. Pat. No. 6,191,725 is directed to an AGC circuit for processing radar signals. The circuit utilizes digital components but requires multiple analog to digital converters (ADCs) operating in parallel to accomplish AGC, increasing the cost and the complexity of the system.
There is, therefore, a need for a digitized RF detection and processing system with fewer components, less complexity, and decreased cost.

Automatic gain control for digitized RF signal processing

The United States of America as represented by the Secretary of the Navy


A power take-off unit includes a drag brake assembly that is automatically engaged when a hydraulically actuated clutch assembly is disengaged. The drag brake assembly includes a brake piston that is axially aligned with the output shaft and is urged into frictional engagement therewith by a spring. When pressurized fluid is provided, the clutch assembly is engaged to cause the output shaft to be rotatably driven by the input gear. At the same time, the pressurized fluid causes the brake piston to retract axially within the cylindrical recess against the urging of the spring. As a result, the brake piston is moved out of frictional engagement with the output shaft to permit free rotation of the output shaft. When pressurized fluid is not provided, the clutch assembly is disengaged to prevent the output shaft from being rotatably driven by the input gear. The lack of pressurized fluid in the clutch chamber to allows the spring disposed within the cylindrical recess to urge the brake piston axially into frictional engagement with the output shaft to retard rotation thereof.

This invention relates in general to a power take-off unit including a hydraulically or pneumatically actuated clutch assembly for selectively driving an accessory from a source of rotational power, such as a vehicle engine or transmission. More specifically, this invention relates to an improved structure for a power take-off unit including a drag brake assembly that is automatically engaged when the clutch assembly is disengaged, and further that is automatically disengaged when the clutch assembly is engaged.
Power take-off units are well known mechanical devices that are commonly used in conjunction with sources of rotational power, such as vehicle engines and transmissions, for rotatably driving a driven accessory. For example, power take-off units are commonly used in a variety of industrial and agricultural vehicles for operating hydraulic pumps that, in turn, operate hydraulically driven devices, such as plows, trash compactors, lifting mechanisms, winches, and the like. A typical power take-off unit includes a housing that rotatably supports an input gear (which is rotatably driven by the vehicle engine), an output shaft (which is connected to the driven device), and a set of meshing intermediate gears. The meshing intermediate gears are connected in a gear train between input gear and the output shaft so as to provide a rotatable driving connection between the engine of the vehicle and the driven accessory. The set of intermediate gears permits one or more speed reduction gear ratios to be provided between the input gear and the output shaft.
In many instances, the power take-off unit further includes a clutch assembly for selectively disconnecting the output shaft from the input gear. The use of a clutch assembly in a power take-off unit is desirable because it permits selective or intermittent operation of the driven accessory without having to turn off the vehicle engine. When the clutch assembly is engaged, the output shaft is rotatably driven by the input gear. Consequently, the driven device is operated by the vehicle engine. Conversely, when the clutch assembly is disengaged, the output shaft is not rotatably driven by the input gear. As a result, the driven device is not operated by the vehicle engine.
During operation, the meshing of the various gears contained within the housing of the power take-off unit can generate significant amounts of undesirable friction and heat. To minimize the adverse effects of this friction and heat, it is common to provide a quantity of lubricating fluid within the housing of the power take-off unit. When the input gear of the power take-off unit is connected to a vehicle transmission, for example, the lubricating fluid may be the transmission lubricating fluid. The teeth of the various gears contained within the housing of the power take-off unit are moved through the lubricating fluid during operation to minimize the adverse effects of friction and heat.
As mentioned above, when the clutch assembly is disengaged, the output shaft is not rotatably driven by the input gear, and the driven device is not operated by the vehicle engine. In this disengaged condition, the output shaft is simply disconnected from the input gear and is allowed to free-wheel within the housing of the power take-off unit. Under most conditions, the combination of being disconnected from the source of rotational power with the inherent resistance to further movement imposed by the load of the driven device causes the output shaft to immediately cease further rotation until the clutch assembly is subsequently re-engaged. Unfortunately, it has been found that under certain circumstances, the relatively viscous nature of the lubricating fluid can cause the output shaft to continue to be at least partially rotatably driven, even though the clutch assembly has been disengaged. This undesirable rotation of the output shaft after disengagement of the clutch assembly can, for example, occur when the temperature of the lubricating fluid is relatively cold and viscous, such as when the vehicle is initially started. Obviously, rotation of the output shaft of the power take-off unit (and, thus, operation of the driven device) after the clutch assembly has been disengaged is undesirable.
To address this, it is known to provide a power take-off unit with a brake system to slow or stop rotation of the output shaft. In one known power take-off unit, an internal drag brake assembly constantly applies a braking force to the output shaft to retard rotation thereof, regardless of whether the clutch assembly of the power take-off unit clutch is engaged for operation or disengaged for non-operation. This constantly-braked power take-off structure is undesirable because it requires frequent adjustments to insure that the proper amount of braking force is applied to the output shaft. This is because the various components of the brake assembly will wear during use, thus varying the amount of the braking force. Also, wear and heat occur rapidly and frequently within the power take-off unit, resulting in frequent maintenance and repair. Furthermore, the magnitude of the braking force which can be exerted is limited so as to not adversely affect the operation of the power take-off unit when the clutch assembly is engaged for normal use.
In another known power take-off unit, a braking member is mechanically actuated by the clutch assembly of the power take-off unit. In this mechanically actuated power take-off structure, a clutch piston of the clutch assembly is urged toward a disengaged position by a spring. To engage the clutch assembly, fluid (hydraulic or pneumatic, for example) is applied to move the clutch piston against the urging of the spring to an engaged position. The braking member is connected to the clutch piston through a mechanical linkage. Thus, when the clutch piston is in the disengaged position, the braking member is in the engaged position. Conversely, when the clutch piston is in the engaged position, the braking member is in the disengaged position. This mechanically actuated brake assembly structure has been found to be undesirable because the brake assembly cannot be operated independent of the clutch assembly. Rather, operation of the brake assembly is reliant on the successful operation of the clutch assembly. Thus, it would be desirable to provide an improved structure for a power take-off unit including an internal brake assembly which avoids the drawbacks of these known structures.
This invention relates to an improved structure for a power take-off unit including a drag brake assembly that is automatically engaged when a clutch assembly is disengaged, and further that is automatically disengaged when the clutch assembly is engaged. The power take-off unit includes a housing that contains an input gear and an output shaft. The input gear is adapted to be connected to an engine or transmission of a vehicle or other source of rotational power so as to be rotatably driven in a conventional manner. The output shaft is adapted to be connected to rotatably driven accessory, such as a hydraulic pump. The power take-off unit includes a clutch assembly for selectively providing a driving connection between the input gear and the output shaft. The drag brake assembly is provided for automatically exerting a braking force against the output shaft to retard rotation thereof when the clutch assembly is disengaged. The drag brake assembly includes a brake piston that is disposed within a cylindrical recess formed in a bearing cap secured to the housing of the power take-off unit. The brake piston is axially aligned with the output shaft and is urged into frictional engagement therewith by a spring disposed within the cylindrical recess. When pressurized fluid is provided from a source to a clutch chamber, the clutch assembly is engaged to cause the output shaft to be rotatably driven by the input gear. At the same time, the pressurized fluid causes the brake piston to retract axially within the cylindrical recess against the urging of the spring. As a result, the brake piston is moved out of frictional engagement with the output shaft to permit free rotation of the output shaft. When pressurized fluid is not provided from the source to the clutch chamber, the clutch assembly is disengaged to prevent the output shaft from being rotatably driven by the input gear. The lack of pressurized fluid in the clutch chamber to allows the spring disposed within the cylindrical recess to urge the brake piston axially into frictional engagement with the output shaft to retard rotation thereof.
Various objects and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the preferred embodiment, when read in light of the accompanying drawings.

Power take-off unit with automatically actuated drag brake


Provided is an aerodynamic body having rhomboid wings and internal torsion bars which can be twisted to affect a change in the shape of a wing. Individual or multiple swings can slide relative to the fuselage body to affect a change in sweep angle and aspect ratio. Provided is a method of controlling the aerodynamic properties, in order to affect stability and maneuvering, of an aerodynamic body by warping the wings by twisting one or more torsion bars located internal to one or more wings. Additional control can be exercized by sliding one of more wings relative to the fuselage to change the sweep angle and aspect ratio.

1. Field of the Invention
The invention presented is directed toward a variable geometry rhomboid wing aircraft with a mechanical or powered torsion bar to control aeroelastic twist and deflection to produce an aerodynamic body.
2. Description of the Related Art
Control of wing and stabilizer surfaces is essential to controlling the direction of flight of an aerodynamic body. For most aircraft, a system of elevators, a rudder, flaps and slats, and ailerons are used to control the movement of the aircraft. Fine maneuverability and banking flight is enabled by ailerons, which can be manipulated to alter the lift and drag for each wing. Alternatively, a wing may be warped to change its aerodynamic properties and obtain similar effects as with ailerons. The Wright Brothers employed a system of bell cranks and pulleys to warp the wing to obtain a fine degree of flight control and banking turns. Today, as new stronger and more flexible composite materials have become available, wing warping is once again becoming a more practicable approach to controlling flight of an aerodynamic body.
Torsion bars, which can be placed along the length of the wing and connected to the wing tip, are an alternative to the Wrights' bell cranks and pulleys as a means for warping a wing to change its aerodynamic properties. U.S. Pat. No. 5,681,014, which is herein incorporated by reference, teaches the use of a torque tube mounted internally in a wing to produce a helicoidal twist with a maximum deflection at the wing tip, to provide increased lateral roll control, lift, braking and maneuverability. Additionally, torsion bars allow flexible wings to stiffen against forces that would cause wing rotation at high flight speeds. U.S. Pat. No. 4,330,100, which is herein incorporated by reference, teaches a wing twist control mechanism comprising a torque tube, which assists high aspect ratio wings to actively compensate for changes in the aerodynamic loads that affect wing twist.
In addition to controlling the lift and drag of surfaces by warping a wing or attenuating ailerons, an aerodynamic body is also affected by the aspect ratio, which affects the overall lift to drag ratio. Aspect ratio is equal to the wing span2/wing area. Thus a longer wing span results in a greater lift to drag ratio of the aerodynamic body. Wing sweep angle is another important aspect in the design of an aerodynamic body. Wings with a lesser sweep angle (i.e., less swept back) have greater lift. Wings having a greater sweep angle, while having less lift, will delay undesirable compression effects at speeds close to the speed of sound. Variable geometry wings are a solution to allowing optimal lift at low air speeds and optimal stability at near sound speeds.
Variable geometry rhomboid wing aircraft are a type of joined wing concept where the two forward wings are swept back, while the rear wing is swept forward. Each pair of forward and rear wings on the same side are then joined at a point along the wing surface and form a triangular shape from the two wings and the section of the fuselage between the wings. The angles in this triangle are allowed to vary by making either of both of the wing mounts variable in position on the fuselage. This type of wing assembly has improved aerodynamic properties as some flight control parameters can be adjusted during flight by varying the wing positions. U.S. Pat. No. 5,899,410, which is herein incorporated by reference, teaches an aerodynamic body having coplanar joined wings forming a rhomboid wing.

Device and method of control of fixed and variable geometry rhomboid wings


The present invention provides a method for dynamically refine the threshold values of R(Red), G(Green), B(Blue) colors for determining a borderline pixel in response to the values of a background image, thereby to precisely determine the borderlines of the Area of Interest (AOI). The method of the invention first searches the borderline pixels of a scanned image according to the standard differences of the R,G,B values of the pixels. Then, approximate the R,G,B threshold values of the borderline pixels by repeatedly averaging the current R,G,B values of the borderline pixels and the previous R,G,B threshold values until the difference is less than a predetermined value. The approximated R,G,B threshold values are set for the new R,G,B threshold values for determining the attribute of a pixel for subsequent prescanned images. Accordingly, the AOI can be automatically selected by reading the image circumscribed by the borderline pixels.

A. Field of the Invention
The present invention relates to a method for auto-cropping a scanned image, especially to a method which can dynamically refine the threshold values of R(Red), G(Green), B(Blue) colors for determining borderline pixels in response to the values of a background image, thereby to precisely determine the crop range.
B. Description of the Prior Art
A conventional method for auto-cropping a scanned image is performed after the process of prescan. The auto-crop technology involves in precisely distinguishing the Area of Interest (hereinafter referred to as AOI) from a background image by finding the borderlines of the AOI. Since the color of the background image is usually black, so the R,G,B values of a background pixel is supposed to be very close to one another. Ideally, the R,G,B values of a background pixel shall be all zeros. In contrast, the colors of the AOI is full of variety. And, the R,G,B values of the AOI pixels shall be non-uniform. Accordingly, it is easy to tell a background image pixel from an AOI pixel by checking the standard differences of its R,G,B values.
Conventionally, a detection procedure is performed by checking the R, G, B, values of each pixel row by row and column by column. In general, if the differences of the R,G,B values of a pixel exceeds a predetermined value, the pixel is determined to be an AOI pixel. If not, the pixel will be determined to be a background pixel. The borderlines of the AOI refer to the background pixels that circumscribes the AOI. To provide a criteria for determining the R,G,B values of a background pixel, the conventional technology applies constant R, G, B threshold values for distinguishing a background pixel from an AOI pixel.
However, the constant R,G,B threshold values can not provide sufficient information for distinguishing a background pixel from an AOI pixel under various circumstances. For instance, when the color of the original itself is darker than the background color, then the background image will be mistaken as part of the AOI if the R,G,B threshold values are set too high. On the other hand, if the R,G,B threshold values are set too low, the AOI pixels will be mistaken as background pixels. Eventually, the R,G,B threshold values determine the precision of auto-cropping.
In fact, distinguishing a background pixel from an AOI pixel is not straightforward. For one reason, the background image is a reflection image from the cover of the scanner. Usually the cover of the scanner is made of black material. When a light source emits light onto the black cover of the scanner, the reflection image of the black cover is suppose to be uniformly black. Nevertheless, once the black material is made of unqualified material or flawed in manufacture, the reflection image will generate unexpected results.
Moreover, the variety of scanner models and the types of light sources should also be considered. Since the intensity of the light will be getting stronger after power-on and then getting stable after a period of time, so the background image will not be uniformly black if scanned during the warm-up process. In such case, if the scanner need to run a warm-up process after power-on or the light source is unstable, then the light intensity of a scanned image will be unevenly distributed. In addition, it is also possible that the color of the original itself may be darker than the color of the cover. Consequently, it is difficult to tell a background pixel from an AOI pixel based on constant R,G,B threshold values.

Method for auto-cropping a scanned image


An orientation adjusting apparatus includes a support base plate set rotatable relative to a mast about a first vertical axis. An azimuth bracket is rotatable relative to the top plate of support base plate set about a second vertical axis. An elevation bracket is rotatable relative to an elevation fine tune bracket about a first horizontal axis. The elevation fine tune bracket is rotatable relative to the azimuth bracket about a second horizontal axis. An azimuth angle fine tuning unit is operable to rotate the azimuth bracket relative to the top plate of support base plate set about the second vertical axis. An elevation angle fine tuning unit is operable to rotate the elevation fine tune bracket relative to the azimuth bracket about the second horizontal axis.

1. Field of the Invention
This invention relates to an orientation adjusting apparatus, and more particularly to an orientation adjusting apparatus for a satellite antenna set, which can fine tune the azimuth and elevation angles of the satellite antenna set.
2. Description of the Related Art
A satellite antenna mechanism typically includes a signal receiver device and an orientation adjusting apparatus for adjusting and fine tuning the azimuth and elevation angles of a satellite antenna set. During adjustment, lock bolt units are loosened to allow for manual adjustment of the orientation of the satellite antenna set relative to a base. The lock bolt units are tightened after adjustment so as to lock down the orientation of the satellite antenna set. However, manual adjustment is troublesome, and makes it difficult to accurately adjust the orientation of the satellite antenna set.

Orientation adjusting apparatus for a satellite antenna set with fine tuning units


A header ring for use in a stuffing box comprising an annular body portion of an elastomeric material, an annular radially inward projecting sealing lip portion formed on said body portion and an annular, axially facing pedestal portion formed on said body portion, said pedestal portion defining an annularly extending radially inwardly facing pedestal surface, the sealing lip portion defining an annularly extending, radially inward facing sealing surface, the sealing surface and the pedestal surface forming a juncture, at least a portion of the pedestal portion adjacent the juncture and forming the pedestal surface and at least a portion of the sealing lip portion adjacent the juncture and forming a portion of the sealing surface being comprised of a layer of reinforced elastomeric material bonded to the body portion.

Field of the Invention
The present invention relates to a packing or seal assembly for a pump and more particularly to a header ring for use in such an assembly.
Description of Prior Art
Piston pumps or plunger pumps are positive displacement pumps and are commonly used in environments where the fluids which are being handled pose problems such as high temperatures, viscous and very viscous media or solids-charged liquids.
One important use of plunger pumps is in the oil and gas industry and particularly in the drilling, completion and/or stimulation of oil or gas wells. In these applications, it is common to employ solids laden drilling fluids, e.g., muds, cement slurries, fracturing slurries, acids and the like, which frequently must be pumped under high pressure into the well. This is particularly true in the case of completion and/or stimulation procedures where very high pressures are employed and the fluids being handled are typically slurries which make the fluids highly abrasive because of the large solids content of the slurries.
As is well known in the art, positive displacement reciprocating plunger-type pumps in this environment pose difficult sealing problems at the high pressure end where the abrasive fluid must be prevented from leaking between the reciprocating plunger and the cylinder or housing within which it reciprocates.
Although a variety of sealing or packing systems are known to seal between the reciprocating plunger and the cylinder, a typical seal arrangement comprises one or more V-shaped or Chevron packing rings with various male and female adaptor rings at the forward and rearward ends of the packing assembly. To ensure sealing between the plunger and the cylinder, the sealing assembly can be placed under compression by an adjusting ring, spring loading, etc.
A typical packing assembly of the type under discussion includes a header ring which is typically made of an elastomeric material. The header ring can be constructed of a homogeneous elastomeric material or an elastomeric material containing layers of cloth or other reinforcing type materials. It is also known to cover certain surfaces of the header ring, particularly the so-called rearward surfaces with a reinforcing fabric.
It has been found that, with respect to the header ring, failure of the sealing assembly primarily occurs due to a phenomena known as "nibbling." This nibbling phenomenon can be best understood by reference to FIGS. 1-4 which depict prior art construction for header rings of the type under consideration. FIG. 1 depicts a typical homogeneous elastomeric header ring shown as 10. As can be seen in FIG. 1, header ring 10 is made of a homogeneous elastomeric material and comprises an annular body portion 12.
Integrally formed with body 12, is an annular, radially inwardly projecting wiping lip 14, an annularly extending, axially facing bead 16, an annular pedestal portion 18. Header ring 10 includes a forwardly facing, annularly extending planar surface 20, an annularly extending, radially outwardly facing cylindrical surface 22, an annularly extending, radially inwardly facing cylindrical surface 24 and a radially inwardly facing convex sealing surface 26, surfaces 24 and 26 being adjoined at an annularly extending juncture 28.
Referring now to FIG. 2, the header ring 10 is shown after use and after a portion of the header ring has been nibbled out. As can be seen, the nibbled out area indicated at 30 comprises a portion of header ring 10 formed by intersecting surfaces 24 and 26. More specifically, it can be seen that the juncture 28 shown in FIG. 1 between surfaces 24 and 26 has been gouged out due to the nibbling effect.
FIGS. 3 and 4 depict another prior art header ring, FIG. 3 depicting the header ring in its original or undamaged state, FIG. 4 depicting the header ring of FIG. 3 following use and damage as a result of nibbling. The header ring 10A shown in FIG. 3 has a body portion 32 comprised of first body section 34 and second body section 36. Section 36 of body portion 32 comprises a fabric or fiber reinforced material while portion 34 is formed of a homogeneous elastomeric material construction. As in the case of header ring 10, there is an annular pedestal 38, an annular bead 40 and an annular sealing lip 42. FIG. 4 shows the header ring 10A of FIG. 3 which has been damaged due to nibbling and once again the nibbling has occurred at the juncture 46 between radially inwardly facing cylindrical wall 43 and radially inwardly facing surface 45.


A method is provided for automatically or manually optimizing independent ground travel operation in an aircraft equipped with one or more self-propelled nose or main wheels powered by a driver means, wherein selected operating parameters indicative of optimized ground travel are monitored by sensors or detectors to provide data and information relating to the selected parameters during operation of the ground travel system. Selected operating parameters can include, for example, speed, direction of travel, torque, component thermal data, aircraft location data, and operator inputs, commands, and feedback, as well as other operational data or information. Data is collected, recorded, and analyzed to enable changes to be made to the ground travel system components in real time automatically by intelligent software or manually by a system operator or at a later time to ensure optimum operation of the system.

The operation of airlines and airports today focuses on achieving maximum efficiency to keep operating costs as low as possible while continuing to provide travelers with a safe and economical mode of travel. Arriving and departing aircraft must travel on the ground between landing and subsequent takeoff along runways and taxiways associated with an airport. It is acknowledged that many, if not most, delays in aircraft arrivals and departures result from delays in aircraft ground travel between landing and takeoff. It is additionally acknowledged that minimizing the time an aircraft spends sitting idle on the ground between taxi-in after landing and taxi-out prior to takeoff maximizes airline and airport savings. At many airports, space is constrained. Aircraft that are waiting to be towed or pushed back block the ramp area and taxiways, delaying the movement of incoming aircraft into the gate and blocking the transit of ground vehicles. It is desired to keep the time an aircraft spends on the ground at an airport between landing, arrival at and departure from a gate, and take-off to the minimum required to unload arriving passengers and cargo, service the aircraft, load departing passengers and cargo, and move the aircraft to and from the gate. Minimizing aircraft ground time not only reduces delays in airline flight schedules, but also increases the possibility that an airline can schedule additional flights, providing travelers with more options and improving airline profits.
The ground movement of landing aircraft is currently controlled by the aircraft's main engines until the aircraft reaches an arrival parking location. Upon departure, the aircraft is typically pushed away from its parking location by a tow vehicle to a more distant location where the engines can be started and used to move the aircraft to a runway for takeoff. The use of an aircraft's engines to move an aircraft at taxi speeds on the ground presents several challenges, including the dangers posed to persons and vehicles in the vicinity by jet blast and engine ingestion. Additionally, engine useful life may be shortened, not only by damage from foreign object debris, but also from sustained operation at the low speeds required for ground travel.
The use of vehicles that tow an aircraft a greater distance onto a runway than the distances traveled by currently available tugs or tow vehicles has been proposed. While this may diminish somewhat the use of an aircraft's engines during taxi, it does not necessarily shorten the time the aircraft spends on the ground and requires the maneuvering of additional vehicles and the personnel to attach and detach these vehicles from aircraft on already crowded runway and taxiway space.
Moving an aircraft on the ground during taxi by means other than the aircraft's main engines or turbines has been described in the art. U.S. Patent Publication No. US2009/0294577 to Rogues et al, for example, describes a device that enables an aircraft to move autonomously on the ground that employs a very specifically defined spiral drive gear to turn an aircraft wheel. The torque and speed of the wheel driver may be controlled according to parameters from other aircraft systems. Processing data relating to the operation of the device and making the required adjustments automatically, or even manually, to achieve optimized operation or performance is not suggested, however. In U.S. Pat. No. 7,445,178 and PCT Patent Publication No. WO2006/138267, McCoskey et al describe a powered nose aircraft wheel system useful in a method of taxiing an aircraft that can minimize the assistance needed from tugs and the aircraft engines. A precision guidance system including ground elements that interact with aircraft elements is disclosed for controlling movement of the aircraft on the ground during taxi. McCoskey et al, however, is completely silent with respect to whether the performance of this powered nose wheel could be optimized in any way to provide efficient aircraft ground movement and, if so, how that might be accomplished. U.S. Pat. No. 7,226,018 to Sullivan also describes a wheel motor useful in an aircraft landing gear wheel designed to provide motive force to an aircraft wheel when electric power is applied. Sullivan also fails to suggest any method for optimizing the performance and efficiency of the described wheel motor to move the aircraft effectively on the ground. U.S. Pat. Nos. 7,975,960 and 8,220,740, both to Cox et al and owned in common with the present application, describe a nose wheel control apparatus capable of driving a taxiing aircraft without the use of the aircraft main engines or tow vehicles. A method for automatically or manually optimizing the efficiency and performance of this apparatus is not suggested, however.
It would be highly desirable to be able to obtain and analyze information relating to the operation of an aircraft ground travel system and then make any required system adjustments automatically, or even manually, to optimize the efficiency and performance of aircraft ground travel. It would be desirable as well to utilize fully the benefits of a powered aircraft drive wheel capable of moving an aircraft efficiently during ground travel without engines or tow vehicles in optimizing ground travel system performance. The prior art has not provided a method for automatically or manually optimizing the performance and efficient operation of an aircraft ground travel system that employs one or more drive aircraft nose or main wheels powered by one or more onboard drivers to effectively move an aircraft independently on the ground.

Method for optimizing operation of aircraft ground travel drive system


The present invention discloses a novel recombinant protein antigen and a vaccine composition using the same, in which the novel recombinant protein antigen is derived from the conserved sequence of a TSA56 antigen and can be useful in the diagnosis of infection with tsutsugamushi and as a vaccine for tsutsugamushi.

Tsutsugamushi disease (scrub typhus) is an arthropod-mediated infectious disease occurring when chigger mite larvae infected with Orientia tsutsugamushi (hereinafter referred to as "tsutsugamushi") bite a person, and it is estimated that at least one million patients are afflicted annually, mainly in the Asia-Pacific region, such as the Russian Federation, Korea, Japan, China, Southeast Asia, northern Australia and the like. Patients who are bitten by infected chigger mite larvae show symptoms such as fevers, chills, scab formation, rash, myalgia and lymphadenopathy through an incubation period of 1 to 2 weeks. If the disease is diagnosed at an early stage of infection, treatment with appropriate antibiotic prescription is possible, but early clinical symptoms are similar to other febrile infectious diseases, and thus distinguishing the same at the time of diagnosis is difficult, and moreover, there is no convenient and quick diagnostic method in the clinical field. Hence, development to severe systemic febrile illness is frequent, and the number of deaths every year is high.
Tsutsugamushi is known to have a wide variety of serotypes or genotypes, and is classified into tens of subtypes (strains), including prototypes such as Gilliam, Karp and Kato, which are traditionally known (Eisemann and Osterman 1985, Am. J. Trop. Med. Hyg. November; 34(6):1173-8; Akira Tamura and Akiyoshi Kawamura 1991, J. Clin. Microbiol. February 1991, Vol. 29, No. 2; WOO-HYUN CHANG et al. 1993, J. Clin. Microbiol. March 1993, p. 598-605). The genotypes of Tsutsugamushi are classified based on a gene encoding a 56 kDa type-specific antigen (TSA56), which is the main membrane protein of this bacterium. In Korea, most infections are of the Boryong genotype, which is similar to the Karp genotype, and the kinds and frequencies of genotypes of tsutsugamushi, which are found in countries where tsutsugamushi disease is occurring, are known to vary widely.
Protective immunity induced by infection with tsutsugamushi in a human or mouse infection model is known to be specific to the genotype of infected tsutsugamushi, and the persistence of the antibody response is relatively short, on the order of 1 to 2 years. No protective immunity is conferred upon secondary infection with an additional genotype. For example, a case of tsutsugamushi disease has been reported in a patient who was infected with Gilliam serotype and was then re-infected with Karp serotype after 2 months. Because of the genetic diversity of tsutsugamushi, effective vaccines have not yet been developed, and serologic diagnosis of this disease is difficult. In recent years, there have been reports of antibiotic resistant bacteria in Southeast Asia, India and the like, and increasing numbers of cases are reported in East Asia, including Korea and China, which is a major public health problem. Accordingly, there is a growing need to develop techniques that are able to effectively and rapidly diagnose infection with a variety of tsutsugamushi genotypes and to provide effective protective immunity.
Various studies have been conducted over the past 70 years with the goal of developing tsutsugamushi vaccines. In the early development of the tsutsugamushi vaccine, a killed vaccine resulting from formalin treatment or gamma irradiation was found to be unable to provide effective protective immunity to humans, and recombinant protein vaccines (Subunit vaccine) using TSA56 (56-kDa Type-Specific Antigen) protein and 47 KDa outer membrane protein, DNA vaccines and the like have been studied, but these vaccines have been reported to induce transient protective immunity only for infection with the same genotype, and have not been shown to induce protective immunity against other genotypes (Buckland and Dudgeon, 1945; Lancet 2, 734-737; Kawamura et al., 1940. Trop. Dis. Bull. 37, 269-270; Seong et al., 1997. Infect. Immun. 65, 1541-1545; Yu et al., 2005. Am. J. Trop. Med. Hyg. 72, 458-46).
Therefore, it is necessary to overcome these genetic differences and develop vaccine antigens capable of providing universal protective immunity against various genotypes or serotypes. It is also urgently required to develop diagnostic antigens that are needed to diagnose various genotypes effectively and early.

SEOUL NATIONAL UNIVERSITY R&DB FOUNDATION


A wetness indicating composition is disclosed that changes color in response to a change in pH. The composition comprises a water-insoluble, thermoplastic polymer composition, a superabsorbent polymer, a wetness indicator, and surfactant. The wetness indicating composition is useful in disposable absorbent articles, e.g., disposable diapers, feminine napkins, medical dressings and beddings for humans and animals.

This invention relates to compositions capable of indicating when an absorbent product has become wet with liquids such as water, body fluids (e.g., blood, urine) and the like, articles employing such compositions, and methods of determining if an article is wet.
Absorbent articles, such as disposable diapers (including adult incontinence undergarments), feminine hygiene products (including sanitary napkins), medical dressings, bedding (both human and animal), wetness indicators used with home clothes dryer, etc. are designed to absorb and hold liquids such as water and body fluids. Often the article employs a superabsorbent polymer (SAP) to facilitate the absorption of the liquids. It is desirable to know when the absorbent articles have become wet with such liquids so that they can be changed before they leak. However, it is not always readily apparent to know when that time has come due to the protective coating layers on, and/or garments worn over, the absorbent articles. Accordingly, there remains a need to provide a mechanism by which a care giver such as a parent, nurse, day care provider, home health care aide, pet owner, etc., can easily determine if the article is wet, and if so, change it in a timely manner.


Techniques for securely updating a point-of-sale (POS) system that includes a merchant-facing device and a buyer-facing device are described. For instance, the merchant-facing device may execute first software that provides first POS functionality and the buyer-facing device may execute second software that provides second POS functionality. To update both devices, the merchant-facing device may receive a software update from a payment service via a network connection, and update the first software using the software update. The merchant-facing device can then cause, via a physical connection, the buyer-facing device to reboot in an update mode and send the software update to the buyer-facing device. In response, the buyer-facing device can update the second software using the software update and then reboot in a payments mode. In some instances, the buyer-facing device can then update a secure enclave on the buyer-facing device using the software update.

Merchants may conduct transactions for items and services with customers. During a transaction between a merchant and a customer, the merchant can use a point-of-sale (POS) device to input information associated with the transaction. For example, the merchant can input information describing items that the customer is acquiring from the merchant, respective prices of each of the items, and payment information of a payment instrument being used by the customer. The POS device can then send a request to a payment service to process the payment instrument for a price of the transaction.
In some instances, the POS device may be connected to a separate electronic device that customers can use to input payment information of payment instruments during transactions. For instance, a customer may input payment information into the electronic device, which can then send the payment information to the POS device for authorization. However, when a POS device is connected to such a separate electronic device, security problems can arise with regard to stealing of sensitive information, such as the payment information. For instance, software may be loaded on the POS device, such as when the POS device is updated, that steals the sensitive information.

Securely updating software on connected electronic devices