One embodiment of the present invention sets forth a technique for mitigating fractional spurs in fractional-n frequency synthesizer circuits. The technique involves advantageously modifying certain least significant bit values in the programming bits of the fractional-n frequency synthesizer circuit to avoid pathological fractional bit patterns. As a result, fractional spurs present in conventional fractional-n frequency synthesizer circuits may be attenuated, thereby improving the overall quality of the resulting out signal.

1. Field of the Invention
Embodiments of the present invention generally relate to synthesized frequency generators, and more specifically to mitigating fractional spurs in fractional-N frequency synthesizer systems.
2. Description of the Related Art
Many conventional electronic systems require a plurality of signal sources, each with specific frequency characteristics. In certain systems, at least one signal source may need to generate arbitrary frequencies, with a requirement of high precision and spectral purity within a specified range. For example, to satisfy certain technical and regulatory requirements, many radio-frequency (RF) transmission systems require very precise frequency control and very high spectral purity in signal sources used in the transmission of RF signals.
A fractional-N frequency synthesizer is one common form of signal generator that may be configured to generate arbitrary frequencies within a specified range. FIG. 1 is a block diagram of a typically fractional-N frequency synthesizer 100. The fractional-N frequency synthesizer 100 typically incorporates a variable frequency oscillator, such as a voltage-controlled oscillator (VCO) 116, and control circuitry configured to form a closed-loop feedback control system for controlling the frequency of the variable frequency oscillator. The control circuitry conventionally includes a phase-frequency detector (PFD) 110, a charge pump 112, a loop filter 114, a feedback divider 120, and a sigma-delta modulator 122. The PFD 110 continuously generates an error signal that is proportional to detected phase error between two input signals such as a reference clock 130 and a feedback clock 132. The charge pump 112 operates on the error signal to generate error pulses, which are transmitted to the loop filter 114. The loop filter 114 integrates the error pulses over time to generate a filtered control voltage. The VCO 116 operates in response to the control voltage to generate an oscillating output signal with a frequency that is a function of the control voltage. The VCO output signal 134 is transmitted to the feedback divider 120, which generates the feedback clock 132. The feedback clock 132 is transmitted to one input of the PFD 110 for comparison with the reference clock 130, which is coupled to the second input of the PFD 110. Using this architecture, the VCO 116 may be controlled in a closed-loop regime to generate an arbitrary multiple of the reference clock 130.
The sigma-delta modulator 122 controls the feedback divider 120, which may be implemented with a programmable integer divider. Some programmable integer dividers are implemented with a dual-modulus prescaler. In one embodiment, the dual-modulus prescaler implements a divide by "N/N+1" scheme, such as a divide 8/9 (either divide by 8 or by 9 in any given full countdown cycle). The programmable integer divider may, for example, implement an 8-bit programmable divider. The feedback clock 132 generated by the feedback divider 120 may be, on average, equal to the frequency of the VCO output signal 134 divided by a fixed-point number that includes both an integer and a fraction component. As is well known in the art, the feedback divider 120 achieves fixed-point, or "fractional," frequency division by dithering count values used to control the feedback divider 120. The sigma-delta modulator 122 accumulates clock cycles against the fraction component of the fixed-point number to generate a signed dither value that is added to the integer component for the next count cycle in the feedback divider 120. The signed dither value accounts for short-term accumulated error between the actual frequency of the feedback clock 132 and a target frequency of the feedback clock 132. The feedback clock 132 is compared against the reference clock by the PFD 110, which generates a negative-feedback control signal used within the control circuit to lock the VCO 116 to a frequency corresponding to the reference clock 130 frequency multiplied by the fixed-point number.
Changes in the signed dither value typically produce a slight short-term shift in the frequency of the VCO output signal 134. This type of shift or modulation of the frequency of the VCO output signal 134 may produce spectral noise in the VCO output signal 134. For example, when the signed dither value changes periodically over a period that is relatively smaller than an observation period, the VCO output signal 134 may include a fractional reference noise "spurs". In certain scenarios, such as when the fraction component can divide evenly into the reference clock frequency 130, "fractional spurs" are generated in the VCO output signal 134. In other instances, fractional spurs may be caused by initial conditions of accumulators within the sigma delta modulator. While fractional-N frequency synthesizer circuits are well known to be very suitable for many applications, including RF systems, fractional spurs are extremely undesirable in these same applications because of high spectral purity requirements.
As the foregoing illustrates, what is needed in the art is a technique for mitigating fractional spurs in fractional-N frequency synthesizer systems.

Mitigating fractional spurs in fractional-N frequency synthesizer systems


[Resolving Means] A rolling bearing device with a sensor includes: a tubular fixed bearing ring which is fixed to a vehicle body side; a rotating bearing ring which is rotatably inserted in an interior of the fixed bearing ring and is fixed to a tire side; rolling elements which are rollably disposed between these bearing rings; and a sensor device disposed on a fixed bearing ring side. The sensor device has at least two sensors which are arranged at positions perpendicular to each other in a circumferential direction of the fixed bearing ring, and which are respectively capable of detecting the ground contact load of the tire, the sensor device being so constructed as to be able to detect a ground contact load of the tire based on cycles of outputs obtained from the at least two sensors.

In recent years, in automobiles, various information is required on such as the load acting on wheels and the rotational speed of the wheels in order to affect driving control at the time of traveling. To obtain such information, a proposal has been made to provide a sensor device to a rolling bearing device for a wheel to which the wheel of an automobile is mounted.
The eccentricity of the tire as an example of information concerning the state of the wheel during traveling is brought about by such as a faulty wheel balance, a decrease of tire air pressure, and an unbalanced weight of the tire (e.g., a case where a stone is sandwiched between dual tires of a large-sized vehicle). If the automobile is caused to travel with an eccentric tire, vibrations can be generated to aggravate the riding comfort, and traveling stability can be impaired. In some cases, there is a possibility of the tire undergoing a fatigue to result in a burst.
Accordingly, various techniques for detecting an abnormality of the tire including such eccentric have hitherto been proposed. For example, patent document 1 discloses a device for detecting an abnormality of the tire by disposing in the tire a sensor for detecting the force transmitted from the tire. In addition, patent document 2 discloses a system wherein the tire inflation pressure, the temperature of a belt edge, and the like are measured, and collation is made with a damaged model prepared in advance as a map to thereby affect the monitoring or diagnosis of the vehicle tire.
Meanwhile, as such a sensor device for detecting the load acting on the wheel, a sensor device has been proposed which consists of a magnetic impedance sensor provided on, for instance, the fixed bearing ring and a magnetized portion provided in face-to-face relation to that magnetic impedance sensor (e.g., patent document 3). In this sensor device, however, since the detection by the magnetic impedance sensor is affected by such as the material and the shape of a portion to be detected, there have been problems in that there is a restriction in the selection of the material of the rolling bearing, and that the processing of the magnetized portion and the addition of another member are required for the portion to be detected.
Accordingly, as a rolling bearing device with a sensor in which such a restriction in material selection is small and additional processing is made unnecessary, a rolling bearing device with a sensor has been proposed in which ultrasonic sensors are disposed on the fixed bearing ring to thereby detect the force acting between the rolling element and the fixed bearing ring as echo ratios (e.g., patent document 4).
The rolling bearing device with a sensor disclosed in this patent document 4 has a sensor device which is comprised of ultrasonic sensors which are provided at least two positions spaced apart a predetermined interval in the circumferential direction of a fixed-side bearing member and adapted to detect the rolling element load as an echo ratio, as well as a processor for determining from outputs of the ultrasonic sensors at least a component in a vertical direction and a component in a left-right direction among three-direction components of the load acting on the rolling bearing. Additionally, it is stated therein that it is also possible to determine not only the three-direction components but also moments about an X-axis, a Y-axis, and a Z-axis.    [Patent Document 1] JP-2000-203217A    [Patent Document 2] Published Japanese translation of a PCT application JP 2005-528270T    [Patent Document 3] JP-2004-45370A    [Patent Document 1] JP-2006-177932A


A motor includes a bracket that defines an exterior of the motor. A PCB is held within the bracket and has a circuit pattern and various elements mounted thereon. A stator is provided on the PCB and a rotor is provided within the stator. A shaft rotates together with the rotor to transmit a rotational force of the rotor. A stopper projects from an inside of the bracket to prevent the rotor from moving along the shaft.

1. Field of the Invention
The present invention relates to a motor, more particularly, to a motor that is easily fabricated with enhanced efficiency and durability, and which has a compact structure convenient to a user.
2. Discussion of the Related Art
Generally, a shading coil motor is used in to a refrigerator or a freezer as a fan motor. A shading coil as well as a main coil is wound around a stator in the shading coil motor.
The shading coil is configured to start a rotor. The shading coil, together with the main coil, forms an oval shaped magnetic field to start the rotor. When the rotor is rotating, the shading coil is no longer needed and wastes electricity.
Moreover, auxiliary teeth should be provided at the stator to wind the shading coil there around, which makes the shape of the stator complex, and the shading coil should be additionally wound around the teeth, which makes the winding complex.
Because the shading coil motor uses a 1-phase alternating current power to reduce the number of electric and electronic parts, the shading coil motor has an advantage of being low cost. However, usually the shading coil motor consumes and wastes a lot of electricity.
Also, it is difficult to control the shading coil motor and there is a further disadvantage of being large size.
Thus, demands for a motor, which can reduce electricity consumption and having a compact exterior that is easily fabricated, have been increasing. The motor may not just operate a fan but appropriately control a fan speed and torque.


A method and system for performing instruction of handwriting skills by animated display of the required stroke motions with simultaneous audio verbal description of these same motions, including the means for a student to practice this lesson with use of a pen based input device by which the pen motion is captured, displayed on a computer monitor, and communicated to an evaluation algorithm which rates the quality of the writing. Based on this handwriting evaluation, the system includes means to provide visual and auditory reward, and generate the subsequent instructions and exercise for the student using embedded expert teaching knowledge. In the preferred embodiment, a tablet with a fastening mechanism fixes into position the paper duplicate of the handwriting lesson presented on the computer screen and the pen writing device is a special ballpoint pen capable of leaving a hard copy trace of the student writing.

1. Field of the Invention
This invention relates generally to EDUCATIONAL AND DEMONSTRATION SYSTEMS for use with computers and other information processing systems. Particularly, the present invention relates to the teaching of WRITING OR PRINTING BY HAND. More particularly, the present invention relates to a system and method for teaching of handwriting or penmanship using a digital computer interfaced to a pen or stylus input device with software for providing instruction and guidance on letter formation. Such a system will be useful for supplementary classroom instruction, the self-instruction of students at home, and remedial education of students with learning/motor disabilities in both manuscript and cursive writing styles.
For the purposes of this present invention, pen based computer refers to a computer which has a special electronic pen or stylus which can function as an input device. In the preferred embodiment there is a tablet associated with the pen device which electronically senses and acquires information about the pen tip motion for communication to the computer software.
2. Description of the Prior Art
Various systems are known for use in teaching handwriting skills. The simplest such systems use a book of worksheets with printed letter samples serving as templates to be traced over by the student using a conventional pencil or pen. By having the student trace a number of letters, the student is expected by repetition to gain the habit of correct letter formation. However, this system requires a human teacher to recognize if the student is forming the letters properly. Cohen in U.S. Pat. No. 5,040,986 discloses a device to assist in teaching children to write with proper shaped letters by controlling their pen motion by mechanical means. While the student is thus ensured of forming the arcs "programmed" by the device by orientation of its apertures, pen movement is practiced in a physically constrained space so that motions practiced may not be "learned" or translate into improved ability to perform unrestricted writing. Cohen's device also concentrates on the teaching of "arcs" rather than teaching the writing of whole letters or even words.
Prior art in image analysis includes pattern recognition systems which perform recognition of handwritten characters. Gaborski et al. in U.S. Pat. No. 5,442,715 discloses a method and apparatus for cursive script recognition. This invention reads handwritten text but it is not designed as a teaching device. Therefore, individual characters or whole words are recognized and the contents of the text read by the apparatus is output, but there is no feedback given to the writer concerning the "quality" of the handwriting. Muroya in U.S. Pat. No. 5,040,222 describes a method for comparing handwritten signatures with a previously stored template and calculating the variation or "distortion" between them. However, the variation calculated in this invention measures deviation from an individual's own signature which is then used to determine writer identification. Because the writing comparison is not performed against a template of ideal character templates, it does not measure absolute quality of the writing, and cannot be used for handwriting instruction.
The prior art further includes computer programs which employ electronic handwriting instruments and writing surfaces for acquisition of the pen motion information. Lally and Macleod (1982,1983) used a computer controlled display screen in conjunction with a digitizer pen. When the student correctly traced a thin guideline on the screen consisting of a 512 by 512 array of controllable neon lights, the display of the line was thickened. The thickening would cease and a cursor would blink to indicate deviation of the pen tip beyond an established set standard from the true path. For the teaching of handwriting, this system has the advantage of showing the student the pen path as it is written, however, this path this invention displays is unnatural in that it stops even though the hand motion continues. Although for this invention the potential motion of the pen is not physically constrained, it does rely on use of a light pen very dissimilar from a conventional pencil or ball point pen usually used by students in school. Roberts and Samuels (1993) modified this system by implementing it on a personal computer platform using a graphics tablet as the input and utilizing the computer monitor for display of the pen path motion. The major improvement of the Roberts and Samuels over the Lally and Macleod device is that the electronic pen is more similar to a conventional pen. However, a disadvantage is introduced in that the student user is forced to look up from the writing tablet to the computer screen for visual feedback of the actual pen path.
All of the above devices are deficient in their ability to serve as a platform for automatic instruction of handwriting. Prior art does not provide for integrated display of instructions for proper pen motion via animated display and associated audio. Also, equipment for these methods does not allow use of a conventional writing instrument therefore they do not provide a realistic display to the student of their actual writing. Prior art also uses a means for letter evaluation which strictly relies on a simple deviation from the model template. This evaluation is therefore not in keeping with current standards of handwriting teaching and evaluation which require evaluation of the "whole" letter.

Pen based computer handwriting instruction


A sucking straw has a substantially flat configuration and is provided with a plurality of adjoining beverage sucking channels. The straw fits the contour of the lips so that no air may go through when liquid is being sucked by the user. The amount of liquid being sucked is substantially greater than with conventional straws.

It is well known that drinks and beverages in general, particularly if they are contained in bottles, cans and the like, can advantageously be sucked by means of a straw. It is also known that conventional sucking straws are made of a plastic material straw element, possibly provided with a bendable top portion. However, known straws are capable of sucking only a very small amount of beverage and the user, in order to meet his/her thirst requirements is compelled to suck the beverage with several quick sucking operations.
Some straws have been designed for providing a rather great flow rate: however these high flow rate straws involve for the manufacture the use of several cascade arranged machines as well as very complex and expensive finishing steps. Thus, these high flow rate straws have a comparatively high cost and have not been marketed to any substantial extent.

Multiple sucking-channel straw for sucking beverages


Provided is a method of operating a dishwasher including a heat pump circuit, wherein a condensate collection container is associated with an evaporator of the heat pump circuit. The method may include the steps of pumping a washing liquid from a sump of the dishwasher using a pump device, opening a first valve in a condensate conduit connecting the condensate collection container with a suction conduit of the pump device, pumping a condensate from the condensate collection container using the pump device. A dishwasher may also be provided.

Dishwashers utilizing a heat pump circuit for heating washing liquid are known in the art. The heat pump circuit comprises an evaporator, a compressor, and a condenser.
EP 2682036 discloses a method for heating washing liquid in a dishwasher. The dishwasher comprises a heat pump. The method involves conducting supply air to an evaporator of the heat pump. Air delivers heat energy to a refrigerant within the evaporator. The evaporated refrigerant is compressed by a compressor. The compressed refrigerant condenses within a condenser and delivers heat energy to washing liquid. Water vapour of the air is condensed within the evaporator. Condensed water vapour of the air, i.e. condensate, is collected in a condensate container and supplied to a washing chamber of the dishwasher. The dishwasher comprises a condensate pump for pumping the condensate into the washing chamber.

Method of operating a dishwasher and a dishwasher


The present invention aims to adjust the height of a musical instrument chair, including an upright rod seat, a pressing plate, a return spring, and an upright rod, wherein the upright rod seat comprises an up-to-down through receiving space and a side opening horizontally communicated with the receiving space; the pressing plate is disposed at the side opening and pivoted to the upright rod seat; the return spring is disposed between the pressing plate and the upright rod seat; and the musical instrument chair is disposed at an upper end of the upright rod, and the upright rod penetrates into the receiving space from up to down, and is provided with a plurality of height-different fastening slots in which the pressing plate is fastened at the normal position so as to fix the upright rod.

Referring to FIG. 1 and FIG. 2, a conventional height adjusting mechanism of a musical instrument chair includes a stand 1. The stand 1 is provided with a central rod 2, a connecting head 3, a screw rod 4, a chair cushion 5 and a fixing ring 6. The fixing ring 6 is in a hollow ring shape, where the interior of an upper segment of the fixing ring is a reducing segment 7, and threads are disposed therein and screwed with the screw rod 4. The interior of a lower segment of the fixing ring 6 is an expanding segment 8, which sleeves a top end of the connecting head 3 and is pressed against an edge face of the connecting head 3 by a radial-penetrating pressing screw 9 so as to fix the fixing ring 6. When the height is adjusted, the pressing screw 9 is unlocked, and then the height of the chair cushion 5 is adjusted in a manner of rotating the screw rod 4. However, the screwing adjustment manner is slow, and cannot meet demands for use.
Also as shown in U.S. Pat. No. 5,927,810, an adjusting rod fixing structure of a musical instrument chair is disclosed. A screw rod can be maintained at a fixed height without shaking, and can be finely adjusted in a stepless manner. However, the structure is complicated and the assembly cost is high; moreover, the screw rod is still fixed in a screwing manner; in case of excessively screwing it down, a weak user cannot make it loosened; and in case of not screwing it down, a danger may be caused due to unexpected loosening.

Rapid fixing structure for height adjusting rod of musical instrument chair


A system is disclosed comprising an engine having coolant passages defined therethrough, a first coolant pump, and a first radiator. The system additionally comprises a second coolant pump, a second radiator, and a liquid-to-air heat exchanger configured to condition the temperature of intake air to the engine. The system further includes a coolant valve means. For a first configuration of the coolant valve means the first coolant pump is configured to urge coolant through the coolant passages in the engine and through the first radiator, and the second coolant pump is configured to urge coolant through the liquid-to-air heat exchanger and through the second radiator. For a second configuration of the coolant valve means the second coolant pump is configured to urge coolant through the coolant passages in the engine and through the liquid-to-air heat exchanger. A method for controlling the system is also disclosed.

Gasoline Direct-injection Compression-Ignition (GDCI) is an engine combustion process that shows promise in improving engine emissions performance and efficiency. GDCI provides low-temperature combustion for high efficiency, low NOx, and low particulate emissions over the complete engine operating range. Low-temperature combustion of gasoline may be achieved using multiple late injection (MLI), intake boost, and moderate EGR. GDCI engine operation is described in detail in U.S. Patent Application Publication No. 2013/0213349A1, the entire contents of which are hereby incorporated herein by reference.
The autoignition properties of gasoline-like fuels require relatively precise control of the thermal state within each combustion chamber to achieve compression ignition and to maintain robust combustion in each individual cylinder of a multiple-cylinder engine. Since there is no spark to initiate the combustion process, the in-cylinder conditions must be correct for auto-ignition. A system and method for conditioning intake air to a GDCI engine is described in U.S. Patent Application Publication No. 2013/0298554A1, the entire contents of which are hereby incorporated herein by reference.
In order to save fuel, it is known to implement engine stop-start strategies, in which the engine is stopped when the vehicle is stopped (i.e. when the engine would otherwise be operated at idle speed), and restarted when vehicle motion is desired. To improve starting performance of a GDCI engine, it is often desirable to increase the temperature of the intake air charge to the engine while starting, as described in U.S. patent application Ser. No. 14/068,278 titled "COLD START STRATEGY AND SYSTEM FOR GASOLINE DIRECT INJECTION COMPRESSION IGNITION ENGINE", the entire contents of which are hereby incorporated herein by reference. Conventional means for increasing intake air temperature such as electric heaters are relatively slow, making them impractical for start-stop operation of a GDCI engine. Accordingly, an alternative way to provide heat to the intake air charge usable during start-stop operation is desired.


A method and apparatus for performing an enzyme-linked immuno sorbent assay of a biological substance in a fluid substrate wherein an enzyme conjugate is used to react with the biological substance to cause the release of ions into the substrate. The change in the resistivity of the substrate due to the release of ions is measured, and an analog signal is generated in response thereto. The analog signal is converted into a digital signal, which is quantized and output in a human readable form for indicating the quantity of the biological substance present in the substrate.

ELISA (Enzyme Linked Immuno Sorbent Assay) test procedures have been developed for the detection of organic substances in blood and other bodily and biological fluids.
The ELISA technique is based upon three primary principles; first, the ability of proteins to bind to plastic; the high affinity and specificity of antigen/antibody reactions and the ability of enzymes to modify a substrate. ELISA assay procedures are well known, and will not therefore be described in great detail herein. Briefly however, a plastic plate having typically 96 individual plastic wells is the receptacle for the fluid sample. Each of the 96 wells is coated with an antibody and an antigen specific to the antibody is bound thereto to hold the antigen in place. A second antibody specific to the same antigen is added and bonded thereto. The second antibody has been covalently conjugated prior to its introduction with an enzyme which will react with a substrate to cause a colour change therein given the right environmental conditions. The degree of colour change in the substrate is proportional to the amount of the biological substance such as an antigen sought to be detected. By passing filtered light through the substrate and measuring its degree of absorption by the substrate using an ELISA reader, one can calculate the concentration of the biological substance therein as a function of the amount of absorbed light, which is assigned a numerical value or index. The greater the colour intensity of the substrate, the greater the absorption of light.
The use of ELISA techniques has increased greatly having regard to the procedure's relative simplicity, speed, reliability, sensitivity and as a means of avoiding the use of radioactive assays.
The disadvantages of ELISA readers that measure light absorption are several. The readers themselves are delicate and sensitive and require constant adjustment to maintain optimal sensitivity. The linear response of the readers falls within a very narrow range so that each test requires large numbers of dilutions so that at least one or two of such dilutions falls within the linear range of the instrument. A relatively intense light source is required making it more difficult to obtain a portable unit having regard to the inherent power requirements of the system, and of course the plastic lens at the bottom of each well must pass the light without distortion, necessitating the use of relatively expensive optical grades of plastic which further adds to the costs. The readers themselves are relatively expensive (prices range from $6000. for relatively simple models, up to $28,000. for units with computerized data management and analytical capabilities) and some existing readers perform only one light measurement at a time, making the reading of a 96 well plate a relatively time-consuming process.

Measurement apparatus for measuring a biological substance within a fluid substrate


A self-driven synchronous rectification circuit which includes two power switches S1 and S2; a transformer Tr having a primary winding Np, a secondary winding Ns and an auxiliary winding Na; two secondary synchronous rectifiers S3 and S4; two diodes D1 and D2; two switching transistors Q1 and Q2; and two zener diodes ZD1 and ZD2. The number of auxiliary winding turns Na of the transformer Tr ensure that the synchronous rectifiers S3 and S4 are supplied with an adequate gate-drive voltage. When S3 conducts, the gate-drive voltage of S4 is clamped by D1 and Q1. Likewise, when S4 conducts, the gate-drive voltage of S3 is clamped by D2 and Q2. ZD1 and ZD2 operate to restrain the gate over voltage of S3 and S4, respectively. When the gate drive voltage of S4 is clamped by D1 and Q1, Q2 disables D2 and when the gate drive voltage of S3 is clamped by D2 and Q2, Q1 disables D1.

The present invention relates to DC-DC converters and, more particularly, to a self-driven, synchronous rectification scheme for a DC-DC power converter.
There is an ever-increasing demand in the power electronics market for low voltage and high current DC-DC converters. As output voltage is desired to be 3.3V or lower, even a state-of-the-art schottky diode with a forward voltage drop of 0.3V has an unacceptable amount of power loss.
Because of this, synchronous rectifier circuits are often used to improve the efficiency of DC-DC converters. Generally, there are two types of synchronous rectifier circuits, self-driven and externally driven. Since the self-driven mode is usually less complex, less costly and more reliable, it is preferred for use with most low voltage DC-DC converter applications.
FIG. 1(A) illustrates a conventional self-driven synchronous rectification, asymmetrical, zero voltage switching (ZVS) half-bridge (HB) topology which is only generally suitable for applications where the output voltage is in the range of from about 3.3V to 6V. Referring to FIG. 1B, the gate-drive voltages Vgs3 and Vgs4 of synchronous rectifiers (SRs) S3 and S4, respectively, are as follows: (1)                               V          gs3                =                                                            2                                                  N                  s                                                            N                p                                                  D                                      xe2x80x83                                                  V              in                                =                                                    2                N                                          D                                            xe2x80x83                                                          V                in                                      =                                                            V                  o                                                  1                  -                  D                                                                          xe2x80x83                                                          (                                                      t                    0                                    ≤                  t                  ≤                                      t                    1                                                  )                                                                        (        1        )                                          V          gs4                =                                                            2                                                  N                  s                                                            N                p                                                                (                              1                -                D                            )                                                  V                              i                                                  xe2x80x83                                                n                                              =                                                                      2                                                        (                                          1                      -                      D                                        )                                                  N                                                          V                                  i                                                        xe2x80x83                                                      n                                                      =                                                            V                  o                                D                                                          xe2x80x83                                                          (                                                      t                    1                                    ≤                  t                  ≤                                      t                    2                                                  )                                                                        (        2        )
wherein, Vin is the input voltage; Vo is the output voltage; D is the steady-state duty cycle; Np is the number of primary winding turns of the transformer; Ns is the number of secondary turns of the transformer; and N is the turn ratio of the transformer. The turn ratio of the transformer TR is calculated by dividing the number of primary windings by the number of secondary windings (i.e. N=Np/Ns).
FIG. 1(B) illustrates the switching waveform occurring in the converter illustrated in FIG. 1(A). As shown in FIG. 1(B), the gate-drive voltage Vgs4 of S4 is always higher than the gate-drive voltage Vgs3 of S3 if D is less than 50%. If we assume that the minimum steady-state duty cycle D at heavy load is 30%, then Vgs3 is about 1.4V, and Vgs4 is about 3.3V. Since most synchronous rectifiers (including logic level devices) only work well with the gate-drive voltage between about 4V and 20V, the circuit shown in FIG. 1(A) only works well when the output voltage V0 is between 2.9V to 6V. If the output voltage is below 2.9V, S3 would be under driven. If the output voltage were above 6V, then S4 would be over driven. In either case the synchronous rectifiers are easily rendered inoperative.
FIG. 2(A) shows a circuit diagram of an asymmetrical ZVS HB converter incorporating the self-driven synchronous rectifier circuit of the invention disclosed in U.S. patent application Ser. No. 09/932,398, filed Aug. 17, 2001, the entire disclosure of which is incorporated by reference herein. The self-driven synchronous rectifier circuit of FIG. 2(A) includes two power switches S1 and S2; a transformer Tr having a primary winding Np, a secondary winding Ns and an auxiliary winding Na; two secondary synchronous rectifiers S3 and S4; two diodes D1 and D2; and two zener diodes ZD1 and ZD2.
In the circuit of FIG. 2(A), when S3 conducts, the gate-drive voltage of S4 is clamped by D1. Also, when S4 conducts, the gate-drive voltage of S3 is clamped by D2. In other words, D1 and D2 prevent S3 and S4 from conducting at the same time. ZD1 and ZD2 operate to restrain the gate over voltage of S3 and S4, respectively. Because of this circuit configuration, the self-driven synchronous rectifier circuit operates normally at various output voltages, such as low output voltages of 2.9V or lower and/or high output voltages above 6V.
FIG. 2(B) illustrates the switching waveform of the converter shown in FIG. 2(A). Vgs1 and Vgs2 represent the gate voltage waveforms of the two power switches S1 and S2. Vp is the primary voltage waveform of transformer Tr. VNa is the voltage waveform of the auxiliary winding. Vgs3 and Vgs4 represent the gate voltage waveforms of the two synchronous rectifiers S3 and S4. Vgs3 and Vgs4 are calculated as follows:                               V          gs3                =                                            N              a                                      N              p                                          D                                xe2x80x83                                          V                          i                                            xe2x80x83                                          n                                                      xe2x80x83                                          (                                          t                0                            ≤              t              ≤                              t                1                                      )                                              (        3        )                                          V          gs4                =                                            N              a                                      N              p                                                      (                          1              -              D                        )                                          V                          i                                            xe2x80x83                                          n                                                      xe2x80x83                                          (                                          t                1                            ≤              t              ≤                              t                2                                      )                                              (        4        )
wherein, D is the on-time of switch S1 in percent duty cycle; 1-D is the on-time of switch S2 in percent duty cycle; Np is the number of primary winding turns of transformer Tr; Na is the number of auxiliary winding turns of the transformer Tr; and Vin is the input voltage.
Comparing equations (3) and (4) above with equations (1) and (2), it can be seen, the gate voltage of self-driven synchronous rectifiers S3 and S4 may be adjusted by selecting the number of auxiliary winding turns Na of transformer Tr. This selection of the auxiliary number of winding turns Na ensures a reasonable gate-drive voltage for the synchronous rectifiers S3 and S4 even when the output voltage is lower than 2.9V or higher than 6V.
Conventionally, the demand for self-driven synchronous rectifier is satisfied by the second scheme. But as logic integrated circuits have migrated to lower working voltages, it is expected that the next generation of integrated circuits will require power supplies with voltage in the 1-2V range. This will confront the second self-driven scheme with great challenges. As shown in FIG. 2(A), in practical application the circuit has a premise:
2Nsxe2x89xa7Naxe2x80x83xe2x80x83(5)
A very low output voltage, namely 1.5V or less, would require a reduction in the number of turns of the winding Ns. However, a reduction in the number of turns of the winding Na would not ensure a reasonable gate drive voltage for the synchronous rectifiers. On the other hand, if the number of turns of the winding Na are made substantially greater than the number of turns of the winding Ns, i.e., if 2Nsxe2x89xa6Na the winding Na will short through the loop of Na, D1, S4 and ZD1 (or the loop of Na, D2, 2Ns, S3 and ZD2). If this occurs, the self-driven circuit shown in FIG. 2(A) will not work.
This invention discloses a novel self-driven scheme that overcomes the above-mentioned drawbacks of the prior art self-driven schemes.
A self-driven synchronous rectifier circuit in accordance with one aspect of the present invention includes an input circuit including a transformer having a primary winding for receiving a voltage, a secondary winding and an auxiliary winding. First and second synchronous rectifiers connected to the secondary winding of the transformer and responsive to the signal across the auxiliary winding are provided for selectively and alternatively turning the synchronous rectifiers ON and OFF. A first clamping circuit is provided for clamping the second synchronous rectifier when the first synchronous rectifier is turned ON and a second clamping circuit is provided for clamping the first synchronous rectifier when the second synchronous rectifier is turned ON. The first clamping circuit includes a first switching device operative to disable the first clamping circuit when the second clamping circuit is operative, and the second clamping circuit includes a second switching device operative to disable the second clamping circuit when the first clamping circuit is operative.
In accordance with another aspect, the self-driven synchronous rectification circuit of the present invention includes two power switches S1 and S2; a transformer Tr having a primary winding Np, a secondary winding Ns and an auxiliary winding Na; two secondary synchronous rectifiers S3 and S4; two diodes D1 and D2; and two zener diodes ZD1 and ZD2; and two switching transistors Q1 and Q2.
In the circuit of the present invention, when S3 conducts, the gate-drive voltage of S4 is clamped by D1 and Q1. Also, when S4 conducts, the gate-drive voltage of S3 is clamped by D2 and Q2. In other words, D1, Q1 and Q2 prevent S3 and S4 from conducting at the same time. ZD1 and ZD2 restrain the gate over voltage of S3 and S4, respectively.
Further, when the gate drive voltage of S4 is clamped by D1 and Q1, Q2 disables D2 and when the gate drive voltage of S3 is clamped by D2 and Q2, Q1 disables D1.

Self-driven synchronous rectification scheme


A method and sensor for sensing the rate of rotation of a fan in order to monitor and detect a variation in the rate of air flowing through the fan, such as to indicate a restriction in the air flow path or failure of the fan. A Hall-effect transistor (HET) is placed in the fixed field of a magnet adjacent the path of a preferably ferrous moving element capable of changing the magnetic field coupled to the HET. As the ferrous element passes the magnet and HET, the strength or alignment of the field changes sufficiently to produce an output pulse from the HET. The pulse rate decreases with slowing of the fan such as may occur with a restriction or blockage in the air flow path.

It is often desirable to detect when an airflow path becomes detrimentally obstructed, such as when a filter becomes clogged or a heat exchanger becomes clogged or freezes over.
Modem automotive and other heat exchangers and air conditioners use electric fans to accelerate the airflow. A fan moving air through a clogged airflow path may suffer a short life and lead to engine damage and/or increased vehicle maintenance costs. Because such fans are often located in hard to reach locations, a failed fan for an automobile air conditioner or cooling system can significantly increase repair costs. It is therefore useful to detect and correct airflow obstructions when such problems occur and before repairs are required. The problem of determining when an airflow path becomes detrimentally obstructed has recently been addressed by placing a sensor in the air flow path and detecting when the airflow rate decreases. Sensors in previous apparatus or this purpose include electrical current sensors (a heavily loaded fan draws additional current), vane switches, pressure switches, and the like.
It is known from U.S. Pat. No. 4,479,115 to Holzhauer to provide a mechanism for automatically determining the speed of a fan, such as a fan used to cool electronic equipment, and/or to determine when the fan has failed, i.e., slowed down or stopped. Holzhauer discloses that one possible approach is to monitor the fan speed by sensing the rate at which an optical path is interrupted by the fan blades. Holzhauer also discloses that it is possible to monitor the fan speed by using a Hall effect device (such as a Hall Effect Transistor or "HET") to sense the rate at which the magnetic field created by the fan motor is rotating.
However, Holzhauer points to a significant disadvantage of the Hall effect device sensors, namely, that the HET must be installed when the fan is manufactured. The relatively heavy magnet required to trigger the HET unbalances the fan blade when added near an external HET sensor. Thus, such an arrangement is not readily retrofit or incorporated into existing installations. That is, it must be an integral part of the initial fan design and cannot, therefore, be conveniently added to existing fans or readily incorporated into existing fan designs. Moreover, stray magnetic fields are well-known to negatively affect the operation of HET sensors. The electric fan motor, of course, generates strong interfering magnetic fields in normal installations unless it is shielded.
In the typical HET, a Hall element, including a plurality of semiconductor materials of different conductivity types, is subjected to a changing magnetic field so as to deflect charge carriers in the Hall element produced by passing a current therethrough. The HET device measures the extent of charge carrier deflection and thus the flux density in terms of a variable voltage appearing between terminals at opposite ends of the Hall element. Such voltage is generally proportional to the flux density through the Hall element, and may therefore be used to measure or otherwise represent a number of different parameters which can be translated into a magnetic field. U.S. Pat. No. 3,835,373 to Matula teaches that a principal difficulty in the use of HET's to measure parameters arises because the magnetic flux density varies hyperbolically in a proportional air gap producing a non-linear relation between position and Hall element output voltage. This nonlinear relationship is highly undesirable in many measurement applications.
The Matula patent discloses a complex rotational positional sensor which utilizes a HET and a means to maintain the Hall voltage constant. The rotational position sensor includes a HET which is mounted in an air gap of variable size within a magnetic circuit. The HET is subjected to changes in magnetic flux density in direct relation to the rotational position of a cylinder member forming a part of the magnetic circuit. The magnetic circuit includes a C-shaped permanent magnet having opposite pole pieces forming air gaps with the cylindrical member. The cylindrical member comprises a half cylinder in the region of the air gap containing the HET so as to vary the effective area of the gap and thus the flux density as the cylindrical member turns. Such a system is very complex and also cannot be readily incorporated or retrofit into pre-existing fans.
U.S. Pat. No. 4,524,932 to Bodziak describes a railroad car wheel detector which utilizes a Hall effect element. The HET is incorporated into a complex integrated circuit package including temperature compensation, voltage regulation, and amplification functions. It is mounted on top of a permanent magnet which is made of ceramic material with the critical Hall axis aligned with the magnet pole axis. The combined permanent magnet and HET assembly is mounted on the rail at a predetermined distance below the top of the rails so that the flange of each passing wheel occupies the air gap between the magnet and the rail through which the major portion of the magnetic flux flows. Reduction of the air gap increases the level of the magnet flux and thus the level of voltage output of the Hall element.
U.S. Pat. No. 4,719,419 to Dawley discloses that one known apparatus for sensing precise shaft position utilizes an annular ring magnet having a plurality of circumferentially oriented poles. The ring magnet is coaxially attached to a rotary shaft and a Hall effect device is attached to a stationary member adjacent the ring magnet. In particular, the ring magnet includes a plurality of magnets connected in series to form a ring with the north and south poles of the magnets alternately arranged. As the shaft and the attached ring magnet rotate, the Hall effect device generates a sinusoidal electrical signal indicative of the magnetic induction or the magnetic flux density produced by the magnets at the Hall effect device. The polarity of the magnetic flux density and the generated electrical signal changes as each pole passes the Hall effect device. The number of signal cycles per revolution of the ring is a function of the number of poles that make up the ring. A counter counts the number of waveform cycles of the signal generated by the Hall effect device. The count is then used to determine the rotary position of the shaft. The accuracy of such a system is dependent upon the number of poles that make up the ring. That is, increasing the angular position accuracy is accomplished by increasing the number of magnets. Such a system is very complex and also cannot be readily incorporated or retrofit into pre-existing fan designs and fans.

Method of and apparatus for detecting the rotation rate of an air moving fan


An injection device for dispensing a dose of a substance, the device including a housing, a dispensing element which can be displaced relative to the housing and a locking element which can be coupled with the dispensing element during or after a substance dispensing operation so that after the dispensing element has effected a dispensing operation once, it can no longer be operated to dispense another dose, and a method of locking an injection device after a substance has been dispensed once, whereby a dispensing element operated to dispense the substance is locked or blocked before, during or after dispensing a set dose so that no more substance can be dispensed.

The present invention related to devices for dispensing, administering, injecting or delivering substances, and to methods of making and using such devices. More particularly, it relates to devices for dispensing a substance, such as injection devices or injection pens, having a dose setting element for administering a set or selected dose of an injectable product. In some embodiments, such injection devices may be used for self-administering a product, may be disposable, and/or may be used with a single or dual chamber ampoule.
Relatively small, easily portable injection devices, which may be referred to as injection pens, are commonly used as a means of self-administering medicaments. Ease of use, accurate dose metering and reliability of the dose setting are important factors for self-administering medicaments, such as insulin or a hormone.
Patent specification DE 10 2004 310, owned by the owner of the present application, discloses an injection device with a dose metering element, which effects a forward drive movement relative to the housing of the injection device in a forward drive direction and a dose metering movement opposite the forward drive direction. The dose metering element is coupled with a conveying mechanism so that the forward drive movement causes a conveying movement of the conveying mechanism. The length of a travel distance determining the dose to be dispensed which the dose metering element covers during the forward drive movement is set by the dose metering movement. The housing constitutes a first catch mechanism in a sleeve portion surrounding the dose metering element and a second catch mechanism formed by the dose metering element or a separate, additional dose metering catch body, and a catch engagement of the catch mechanisms can be released by a dose metering movement of the dose metering element or the separate, additional dose metering body without any rotating motion.
Patent specification U.S. Pat. No. 5,807,346 discloses a measuring instrument for dispensing different doses of a fluid, which has a reservoir for accommodating the fluid, a displaceable toothed rack element axially disposed inside and a pushing element which can be operated by the user. Annular notches are provided on the toothed rack element, and the housing has various axial slots distributed across its periphery. An outwardly projecting pin is provided on the pushing element, which is able to engage in one of the axial slots of the housing, thereby enabling the setting element to be easily extracted by the user.
Patent specification EP 0 713 403 B1 discloses a syringe with a barrel, which defines or has a cylinder. The cylinder has a nozzle at one end and encloses a plunger able to slide in the longitudinal direction inside the cylinder. The distance by which the plunger is able to move inside the cylinder defines the volume administered by the syringe, and the plunger is drivingly coupled with a slide so that it moves parallel with the plunger. The longitudinal distance by which the plunger is able to slide inside the cylinder is defined by restrictions to the movement caused by a stop surface on the barrel or on the slide co-operating with end stops on the slide or barrel. The syringe can be locked in a state in which the stop surface and the end stops are able to move relative to one another within movement restrictions which can be selected from one or more selectable, pre-defined movement restrictions. Because the stop surface has an insert which can be inserted in an orifice in the barrel or slide so that it projects out from it and can only be removed with great difficulty or by using a special tool, the projecting part of the insert acts as a stop surface. The position of each such orifice relative to the end stops defines one of the pre-selected movement distances.


A jewelry clasp is provided with two bodies, each having a surface magnetically attracted to the other. The clasp has a safety catch that includes an arm hinged to one of the bodies. The arm may be swung about the hinge between an open position and a closed position. A further magnetic attraction keeps the arm in the closed position until opened with a fingernail. A retaining wall may extend generally perpendicular to a direction of elongation of the arm to block a path that the other of the bodies could travel if the bodies were to separate from each other while the safety catch is in the closed position. If desired, a male connector may be inserted into a female connector to prevent separation of the bodies from each other. The male connector and female connector are usable in tandem with the retaining wall, or in lieu thereof.

1. Field of the Invention
The invention relates generally to jewelry and more particularly to a magnetic jewelry clasp with a safety catch. While the jewelry clasp is magnetic, the catch may or may not be magnetic. The clasp may include a retaining wall or other device to help retain the safety catch in a closed position.
2. Discussion of Related Art
A conventional jewelry clasp is connected to links of a necklace, bracelet, ankle bracelet or belly chain. By opening or closing the mechanical clasp, the jewelry can be either removed from or secured on the wearer. A second clasp or xe2x80x9csafety catchxe2x80x9d is sometimes provided. This is especially true for more expensive jewelry. A conventional safety catch is also a mechanical connection.
A magnetic jewelry clasp includes two bodies that are held together by magnetic attraction and released from each other by pulling them apart to break the magnetic attraction. Thus, the bodies are movable between a connected condition (when together) and a separated condition (when pulled apart).
The inventor is unaware of a magnetic jewelry clasp which also employs a safety catch. This is probably due to the fact that conventional magnetic clasps do not limit the position for connecting the two sides of the clasp. Thus, while employing a safety catch with conventional magnetic jewelry clasps would add the benefit of added security, it would also eliminate an advantage offered by such clasps by requiring a user to properly align the sides of the clasp for the clasp to be closed. The inventor is also unaware of any magnetic safety catches.
The making and breaking of a magnetic attraction force between the two portions of the clasp renders the magnetic jewelry clasp easy to use. However, it would be beneficial to make the clasp more secure by adding a safety clasp (magnetic or mechanical). Additionally, it would be desirable to make the safety catch easier to use and yet still resist forces that might otherwise break the magnetic attraction force between the two sides of the clasp.
To improve upon the conventional jewelry clasp, the invention provides a magnetic jewelry clasp with a safety catch. The clasp includes two bodies movable between a separated condition and a connected condition. Each of the two bodies has at least one magnetically attractive surface that is attracted to the other in the connected condition. At least one of the magnetically attractive surfaces is formed by a magnet. The other may be a magnet or a magnetically attracted material. The two bodies are arranged to move into the separated condition in response to manual forces that pull the two bodies apart to break the magnetic attraction between the surfaces. The invention also includes a safety catch, connected to one of the two bodies, that includes an arm movable between a catch position and a release position. The safety catch may be magnetic or conventional.
The arm is hinged to one of the bodies and has a free end that may be moved between a catch position and a release position. In the catch position, the arm may be in magnetic attraction with one of the two bodies in accordance with one embodiment or with the magnetic connection between the two bodies in accordance with another embodiment. The arm may be in magnetic attraction with one of the magnets in one of the bodies in an embodiment and/or the arm may be conventionally connected to one of the bodies.
While the arm is in the release position, there may be blocking surfaces that no longer abut even though the two bodies are still magnetically connected to each other. While the arm is in the catch position, the blocking surfaces abut to resist forces that otherwise would tend to pull the bodies apart and break the magnetic attraction between the bodies. These blocking surfaces may also be magnetically attracted to each other.
The arm may enter the release position from the catch position by using the user""s fingernail to flick a free end of the arm in a direction that breaks the magnetic attraction between the arm and the one of the two bodies. Once the safety catch is released, the two bodies may be pulled apart by breaking the magnetic connection between the surfaces that face each other. To close the jewelry clasp, the two bodies are brought together so as to establish the magnetic connection and then the safety catch is secured.

Magnetic jewelry clasp with safety catch


A biodegradable packaging material, a method of manufacturing the same, as well as products made of the material wherein a multilayer coating coextruded onto a fibrous substrate the multilayer coating comprising innermost and outermost layers of a blend comprising 20-95 wt-% of a higher melt index polylactide and 5-80 wt-% of another biodegradable polymer such as polybutylene succinate, and a middle layer containing a lower melt index polylactide alone. The goal is to increase machine speed in coextrusion while maintaining good adhesiveness to the substrate and good heat-sealability of the coating. The products include disposable drinking cups and board trays, as well as sealed carton packages for solids and liquids.

The fibre-based packaging material of product packages, such as packing paper or board, is usually provided with a polymeric coating that makes the package tight and allows closing the package by heat sealing. Similar polymer-coated paper or board is also used for disposable tableware, such as drinking cups. Polyolefins, such as low-density polyethylene (LDPE), are widely used for coating due to their good heat-sealability. A disadvantage of the usual polyolefins is, however, that they are not biodegradable.
Polylactide (PLA), which has reasonably good moisture and gas barrier properties that are sufficient to many applications, has been used as the coating polymer of biodegradable packaging material; however, its use involves a number of problems. Standard low melt index polylactide is stiff and fragile, requiring a high extrusion temperature and a fairly large layer thickness to stick to the fibre substrate of the packaging material. Because of the high temperature, such polylactide runs the risk of deterioration, and in extrusion, the edges of a molten web tend to tear and pin holes easily remain in the extruded layer. This also results in a low machine speed.
To solve the extrusion problems, EP-1094944 B1 discloses an inner adhesion layer, which is co-extruded together with an outer polylactide layer, and which consists of a biodegradable polymer, examples of which, according to the specification, include some commercial copolyesters, cellulose esters, and polyester amides.
Another problem with the use of low melt index polylactide in the outer coating layer of the packaging material is its fairly high melting point, and the resulting poor heat-sealability. As an improvement to this, US-2002/0065345 A1 discloses a biodegradable aliphatic polyester that is blended with polylactide, its portion in the mixture being at least 9%, and a tackifier, its portion in the mixture being at least 1%. As suitable aliphatic polyesters, the publication mentions polycaprolactone (PLC) and polybutylene succinate adipate (PBSA). According to the reference, the mixture can be extruded into a film, which can be axially or biaxially stretched, and which can be attached to the fibre substrate by lamination.
In general, adhesivity to a fibrous base and heat-sealability of PLA may be improved by blending with selected polymeric additives, but these have posed various problems limiting their use. There are non-biodegradable polymers, which can only be used in small amounts so as not to spoil the overall biodegradability of the PLA-based coating layer. Other polymers, which are biodegradable, may be used in larger amounts, but even then problems with runnability on the extrusion coating machine may limit their use.
US 2014/0147604 A1 teaches that a coating containing at least 70 weight-% of polylactide and at least 5 weight-% of polybutylene succinate (PBS) or a derivate thereof has an improved adhesion to the fibrous substrate and reduced raw edge penetration (REP). The high share of 70% or more of PLA is necessary for runnability of the extrusion coating process in a coating machine. Therefore there is an upper limit of 30 wt-% for the share of PBS, even though increasing the PBS share would otherwise be desirable for further improving heat-sealability.
PLA used for coating fibrous packaging materials has usually been low melt index PLA having a melt index at most 25 g/10 min (210° C.; 2.16 kg), due to its suitability for extrusion coating. High melt index PLA is too viscous for being extruded as such. Blending high melt index PLA with other stiffer polymers improves extrudability, while the polymeric additive may be selected from such biodegradable polymers which provide improved adhesion and heat-sealing properties for the blend. At the same time, the share of the added polymer may be raised considerably higher than with standard low melt index PLA.
In WO 2010/034712 A1 there is disclosed a triple layer coating on a fibrous base, comprising innermost and outermost layers of PLA blended with biodegradable polyester as well as a middle layer of either such a blend or mere PLA. The polyester of choice is polybutylene adipate terephthalate (PBAT), but there may also be an amount of other polyesters such as PBS. The PLA used for the multilayer structure is NatureWorks 3251 D, which is a high melt index PLA. This means that the teaching of a middle layer of 100% PLA is in practice unworkable. There must be polyester blended with PLA to turn the material extrudable. In a working example, the share of PLA in the middle layer is 80% and in the inner and outer layers 60%. The stiffer inner and outer layers thus serve to support the looser inner layer in coextrusion.
There still remains a need of improving machine speed in coextrusion processes, while preserving good adhesion and heat-sealing properties of the resulting polymer coated fibrous packaging materials. These objects should be achieved with improved economy and without compromising environmental aspects of the resulting product.

Method for manufacturing biodegradable packaging material, biodegradable packaging material and packages and containers made thereof


A personal driving range apparatus is provided including a platform, a ball having at least one aperture that passes through the ball, at least one line having a first end and a second end. The first end is detachably connected to the platform, and the at least one line is drawn through the at least one aperture of the ball so that the ball is slidably disposed on the at least one line extending from the platform. The apparatus also includes a strap disposed at the second end of the at least one line for detachably securing the at least one line to a stationary object.

1. Field of the Invention
The present invention relates to golf equipment, and more particularly, to an apparatus constructed to return a golf ball when practicing a golf swing.
2. Description of the Related Art
Typically when practicing a golf swing at a driving range, at least one golf ball is required for each swing of the club, and a great deal of room is required for the flight of the golf balls. These two requirements make the execution of a proper golf swing utilizing only a golf ball and a club nearly impossible in confined areas of personal property.
In order to practice a golf swing in a confined area, it would be beneficial for both the ball's flight to be restricted and for the ball to return to the area from which it was hit. Multiple innovations have been proposed that involve the use of lighter, modified golf balls. However, while these modified golf balls prevent the ball from traveling a great distance, the golfers swing may be affected due to the fact that a real golf ball is not being used. Additional innovations involve the use of a tether. When the golf ball is attached to the end of the tether, the tether restricts the flight of the ball and can also be utilized for ball retrieval. However, the tether must also be attached to a stationary object or the golfer, and the flight of the ball may be unpredictable and thereby dangerous to the golfer.


An image is generated from data acquired with a magnetic resonance tomography, wherein nuclear spins in an excitation region are excited with different transmission modes and a common image is generated from the response signals.

1. Field of the Invention
The present invention concerns a method to generate an image with a magnetic resonance tomography apparatus and an evaluation device, as well as a magnetic resonance tomography apparatus.
2. Description of the Prior Art
Magnetic resonance tomography (abbreviated as MRT) has for many years represented one of the central imaging methods of biophysics and medicine.
MRT is based on the alignment of nuclear spins (in particular that of H atoms) in a body by means of a strong, stationary magnetic field (also called a B0 field or basic magnetic field). The nuclear spins can be deflected out of their alignment or can be affected in their alignment by energy supplied to them at a specific resonance frequency (known as the Larmor frequency) dependent on an external magnetic field (such as the B0 field).
Excited spins release energy again and generate a measurable field or response signal. The response signal emitted by the nuclear spins is detected and used for image generation.
Individual aspects of MRT according to the present invention are first discussed in detail.
a) Excitation
A number of nuclear spins are excited simultaneously. The region of a body in which nuclear spins are excited or can be excited simultaneously is designated as an "excitation region". An excitation region is thus a region with essentially the same Larmor frequency. In order to establish or demarcate the excitation region or a sub-region to be evaluated—for example to a slice of a body to be examined—or in order to enable an association of the response signal to a spatial region (such as what is known as a voxel), a spatially-dependent coding takes place by spatially dependent shaping of the magnetic field (and therefore of the Larmor frequency), by the application or superimposition of gradient fields.
The excitation of nuclear spins takes place by supplying energy, in particular by an electrical signal or radio-frequency signal, a magnetic and/or (radio-frequency) alternating field, B1 field, external magnetic field and/or a corresponding pulse (called an "excitation signal" in the following). The excitation signal advantageously has components at the Larmor frequency.
In practice a pulse-like excitation of the nuclear spins preferably takes place, in particular with an excitation pulse. In the following an excitation signal that has a pulse-shaped curve, in particular at least one region with rising and/or falling intensity or amplitude, is designated in the following as an "excitation pulse".
The excitation signal is advantageously generated by superimposing multiple transmission signals of different transmission devices or antennas that can form transmission channels. Particularly at higher frequencies, shadows, interferences and/or inhomogeneities occur, particularly with regard to the spatial field strength distribution. This spatial distribution of the excitation signal is designated according to the invention as a "transmission characteristic". The inhomogeneity of the transmission characteristic of an excitation signal is relevant in excitation region. The transmission characteristic also depends on properties of the surrounding medium, such as the body to be examined or the like.
b) Acquisition
Components or portions of a response signal are also designated as an "acquisition signal". A response signal can thus have multiple acquisition signals or be composed of these.
A response signal is advantageously acquired by means of an acquisition device. Different acquisition signals are particularly preferably acquired or, respectively, measured via multiple acquisition devices (such as acquisition coils or the acquisition device) that can also form acquisition channels.
c) Measurement Sequence and Imaging
In order to also achieve a resolution in the coding or spatial directions, a measurement process—namely excitation with specific coding and acquisition of a response signal—is implemented multiple times repeatedly with different codings. Such a sequence of multiple measurement processes is designated as a "measurement sequence". In particular, a measurement sequence is a series of multiple measurement processes to generate an image with resolution in a phase coding direction.
In the present invention the response signals or their acquisition signals of the measurement processes or measurement sequences are advantageously stored or saved in at least one measurement matrix (also henceforth called a matrix), in particular line by line.
In each measurement process a response signal associated with this is advantageously determined. From the respective response signal a corresponding matrix line of a measurement matrix can be generated with regard to a measurement process, wherein the response signal associated with a measurement process is advantageously split up into spectral portions. The spectral portions can be respectively associated with a matrix element such that a line of the measurement matrix arises with regard to a matrix element or a response signal. In this way a measurement matrix can be successively filled with a measurement sequence.
To generate the image, the measurement matrix that is generated in such a manner is advantageously converted into an image using a Fourier transformation or another evaluation or analysis method. An image of the excitation region (such as a slice of the body to be examined) can be generated from a measurement matrix. This can have a brightness distribution that enables conclusions about the spatially-related properties of the slice, in particular with regard to the spatially-related number of H atoms, information about the chemical composition or the like. Multiple images or slice exposures of different excitation regions are possible with multiple measurement sequences.
For a 3D MRT method, analogous to the described procedure not just one very thin slice but a somewhat thicker slice or an excitation region with a certain extent in the z-direction can be excited transversal to the slice plane, in particular via an excitation signal or an excitation pulse with a corresponding bandwidth. A three-dimensional image can be generated via corresponding coding and evaluation, advantageously again with matrices (in particular multiple and/or three-dimensional matrices).
Measurement matrices and their matrix cells merely represent preferred means of representation for illustration and/or in particular mathematical and/or computational processing. The following explanations using matrices are therefore merely examples. The use of matrices does not represent a requirement for the method according to the invention, although evaluations, analyses and/or image generation are preferably implemented on the basis of matrices. Matrices enable the method necessary to generate an image to be applied in a structured and comprehensible manner. However, the present invention can also be realized with other known and future methods or representations to generate an image from response signals.
d) Image Generation at High Magnetic Field Strengths
In the presently available MRT methods the homogeneity or uniformity of the excitation is essential to the ability to interpret the image. A non-uniform excitation of the excitation region or more or less excited or, respectively, shadowed sub-regions in the excitation region lead to a non-uniform brightness distribution or even to incorrect information in the resulting image.
In order to achieve a high resolution and/or good contrasts, the use of an optimally strong magnetic field is advantageous. The Larmor frequency also simultaneously increases with an increase of the magnetic field strength. Therefore an excitation signal of correspondingly higher frequency must be used to excite the nuclear spins.
Primary magnetic resonance tomographs with magnetic field strengths between 0.5 T and 3 T are currently used. At high field strengths in the sense of the present invention, thus field strengths that are advantageously above 3 T (for example 7T), the Larmor frequency is so high that it increasingly leads to diffraction effects and/or shadows in the body to be examined. In particular, this leads to diffraction effects and distortions of the transmission characteristic. This results in a non-uniform and/or insufficient excitation of the nuclear spins in the excitation region. Therefore different methods (in part very complicated methods) have been developed in order to achieve an optimally homogeneous excitation of a slice or, respectively, of the excitation region, in particular even given use of higher magnetic field strengths.
Methods to homogenize fields to excite nuclear spins today operate most often with transmission devices with multiple transmission units (such as antennas or coils) that can be operated independent of one another, thus with multiple (independent) channels. Channels can be associated with both transmission and acquisition devices. Therefore differentiation is also made in the following between transmission channels that advantageously correspond to transmission devices and acquisition channels that advantageously correspond to acquisition devices. Since it is possible to also use transmission devices as acquisition devices and vice versa, it is possible that multiple channels—in particular one transmission channel and one acquisition channel—can be associated with a transmission and/or acquisition device. Methods with multiple transmission devices or, respectively, multiple transmission channels that can be operated independent of one another are also called multichannel transmission methods. Methods with acquisition devices with multiple acquisition units are henceforth accordingly called multichannel acquisition devices.
In the case of multichannel transmission methods, the excitation signal advantageously consists of multiple transmission signals that are in particular associated with transmission devices or channels. Given multichannel acquisition methods, the response signal can have multiple acquisition signals that in particular are associated with acquisition devices or channels.
In a multichannel transmission method known from DE 101 24 465 A1 (corresponding to U.S. Pat. No. 6,900,636) from which the present invention arises, amplitude and phase positions of different transmission signals or, respectively, for different transmission devices are preset in a fixed manner such that an optimally homogeneous transmission characteristic—thus an optimally homogeneous B1 field—is achieved. The corresponding adaptation of the transmission signals is also called "radio-frequency shimming" or "RF shimming". However, given the use of high magnetic field strengths the method is in particular not in the position to sufficiently reduce shadows.
In another multichannel transmission method (for example that known from DE 10 2004 002 009 A1, corresponding to U.S. Pat. No. 7,218,113) it is sought to affect the transmission characteristic via transmission signals with pre-distorted and temporally variable pulse shapes so that a homogeneous excitation of the excitation region is achieved. These methods are also called "Transmit Sensitivity Encoding" or "Transmit SENSE" but are significantly more complicated in comparison to RF shimming. A separate, more complex pulse generator that supports a variation of amplitude and phase in the time curve of the pulse is required for each transmission device or, respectively, each transmission signal. A similarly complicated determination of the properties of each individual transmission device in advance of each measurement is required for calibration, which leads to time losses in the measurement.
A method known from DE 10 2005 018 937 A1 (corresponding to United States Publication No. 2007/0013374) addresses the calculation of calibration coefficients for Transmit SENSE, wherein individual coils of a transmission coil array are activated individually and corresponding response signals are acquired simultaneously by means of multiple methods. The known method does not address an image generation with multiple transmission modes, nor is the large system cost to implement Transmit SENSE reduced.
WO 2009/053770 A1 (corresponding to United States Publication No. 2010/0301856) discloses a transmission method that resembles Transmit SENSE. However, in contrast to Transmit SENSE constant phases and amplitudes are used at least in certain time segments, which should reduce the complexity of the system.
DE 10 2005 039 686 B3 (corresponding to United States Publication No. 2009/0309594) describes a method to improve contrasts of MRT images. Fields are used that are advantageously right-polarized since this abets the transfer of energy to the spins. In particular at high Larmor frequencies, the acquisition of left- and right-polarized fields takes place since both polarization types can contain information due to distortion effects. However, shadows can also not be effectively prevented or compensated with this method.
An additional limiting factor in MRT is the acquisition time necessary to achieve high-resolution images. In order to optimally reduce the residence time of a body to be examined (such as that of a person) while maintaining resolution and maintaining contrasts, methods have been proposed for partial parallel acquisition (henceforth abbreviated as PPA), wherein additional information from multiple acquisition channels or, respectively, acquisition signals that are independent of one another are used. In this way it is possible to omit measurement processes and to reconstruct the image on the basis of this independent information of multiple acquisition channels in order to achieve the same resolution—in particular in the direction of the time-consuming phase coding (in what is known as k-space)—with a reduced number of measurement processes and accordingly in a shorter amount of time per measurement sequence.
WO 2008/004192 A2 (corresponding to United States Publication No. 2009/0292197) discloses a method to accelerate the acquisition of MRT data in a PPA measurement sequence, wherein a characterization of the transmission units is necessary to process the acquisition signals. The goal of the described method is to reduce the correction cost and the cost to determine corresponding correction data in that a reduced resolution is used for a reference measurement.
DE 10 2005 018 814 A1 (corresponding to U.S. Pat. No. 7,495,437) provides a determination of a special construction matrix by means of which a processing of incompletely acquired data sets or measurement matrices can take place. The computing cost to generate an image under the described requirements should be reduced in this manner.
DE 101 44 654 A1 (corresponding to U.S. Pat. No. 6,734,673) proposes a reconstruction of unacquired lines of a measurement matrix using a sensitivity function for individual acquisition directions or channels, wherein this is described by Fourier series.
From the prior art, at present only Transmit SENSE or its modifications are in the position to effectively reduce or avoid a shadow image given the use of high magnetic field strengths (such as 7 T). Conversely, complicated and expensive devices as well as complex signal processings are required to implement such methods.

Magnetic resonance imaging apparatus, evaluation device, and method


The method may include providing a plurality of historical data vectors, each historical data vector including a value for each of a plurality of empirical variables associated with an apparatus or process. The method may include providing a current data vector including a current value for each of the plurality of empirical variables. The method may include determining a plurality of distance values, each distance value being determined from the current data vector and a different one of the historical data vectors and identifying a minimum distance value from the determined plurality of distance values. The method may include using the identified minimum distance value to determine a condition of the apparatus or process.

It is known to monitor the condition of an apparatus or process for the purposes of reducing or minimising the risk of failure of the apparatus or process and/or to optimise the performance of the monitored apparatus or process. Known conditioning monitoring methods generally involve the repeated measurement of one or more variables associated with the monitored apparatus or process and/or an environment surrounding the monitored apparatus or process over a period of time. The one or more measured variables may vary in response to a change in a condition of the monitored apparatus or process. Additionally or alternatively, the one or more measured variables may vary in response to a change in one or more environmental variables. For example, the one or more measured variables may vary in response to a change in the ambient temperature and/or pressure. Known condition monitoring methods may be used to identify a change in a condition of the monitored apparatus or process even in the presence of a change in one or more environmental variables. Such known condition monitoring methods generally rely on the calculation of a vector of predicted or estimated variable values and a comparison of the predicted variable values with current variable values to identify a change in a condition of the monitored apparatus or process. However, calculating such predicted variable values may be complex and may be difficult to implement. In addition, the method of calculating the predicted vector may not be appropriate for some applications. For example, the method of calculating the predicted vector may be too slow, too inaccurate and or may lack sufficient reliability for some applications.
US2008/0183425 discloses an apparatus and method for monitoring the condition of a power plant in which a non-parametric empirical model is constructed from historical sensor readings to predict or estimate current sensor readings. The predicted sensor readings are compared with current sensor readings to identify changes in the state of the power plant. More specifically, a plurality of memory vectors is provided, wherein each memory vector comprises a set of historical readings taken from a plurality of sensors at a different instant in time. A query vector is provided comprising a current reading from each sensor. A distance between the query vector and each of the memory vectors is determined and a weight is evaluated for each memory vector according to the proximity of the query vector to the memory vector. The weights are subsequently used to determine a vector of predicted sensor readings based on a locally weighted regression. The vector of predicted sensor readings and the query vector are compared to identify changes in the condition of the power plant.

Method and system for condition monitoring


This invention relates to a dating service which allows potential dates to observe the users of the system in their automobiles. The preview of the person allows them to decide if they are compatible in age, attractiveness, and economic level. The potential date could then call a telephone service to hear a brief message about the person""s interests and information, after entering in the automobile""s license plate number. A voice message can then be left for the user of the system for anonymous contact.

This invention relates to a dating service which allows potential daters to observe the users of the system in their automobiles. Recently, dating services have often utilized the Internet for possible date selections. This has left many users unavailable without access or necessary time to wade through profiles. Fraudulent information is often used by people in profiles, and profiles falsely created by dating services to increase attraction to the service and increase fees.
Personals ads in newspapers and local magazines have also long been used for dating selection. This requires long periods of time of calling for additional information about potential dates, and does not provide pictures of the people. In order to get a sufficient amount of customers, the services will bring together a large geographic area of people in the personals ads. Many people do not want to date outside their immediate area.
Today, many busy people are unable to spend time looking for dates. Time demands at work and home have restricted efforts at meeting new people. One source of increasing free time is in commuting time to work, and driving time. Single people often look at other drivers, looking for attractive people to meet. The automobiles rarely provide an opportunity for contact between drivers. There has not been a method of contacting a potential date, or discreetly signaling other drivers of your availability for dating.
The present invention provides a dating service based on automobile notification and contact using the automobile""s license plate or other identifying information. Subscribers to the service will receive a sticker to display on their car. Other drivers can see that they are subscribers to the system and look at their faces, and make of vehicle. If they are interested in dating that person, they can call the telephone number and enter the vehicle""s license plate number or identifying number on the sticker. The subscriber""s recorder message should describe their interests, information, and objectives in dating. The recorder message may also list a telephone pager number, web site address with more information, or email address of the subscriber. The potential date can then leave a voice message, email, or page the subscriber, as desired or available. The subscriber may then respond to their potential dates.
Varying levels of anonymity can be provided for security. Potential dates will know the subscriber""s vehicle, but cannot get a telephone number, name, or address, unless provided in future communications. This allows users to signal their availability, but maintain security, until relatively confident of the other person""s reliability.