Nitride semiconductor devices and methods of producing same are provided. The present invention includes forming a nitride semiconductor layer on a base body of the nitride semiconductor under selective and controlled crystal growth conditions. For example, the crystal growth rate, the supply of crystal growth source material and/or the crystal growth area can be varied over time, thus resulting in a nitride semiconductor device with enhanced properties.

The present invention relates to a vapor-phase growth method for a nitride semiconductor, which can be adapted to form a nitride semiconductor, such as a gallium nitride based compound semiconductor, on a base body by vapor-phase growth, and to a nitride semiconductor device, such as a nitride semiconductor light emitting diode, a nitride semiconductor laser, a suitable nitride semiconductor electron device formed by using the vapor-phase growth method or the like. More specifically, the present invention relates to a vapor-phase growth method for a nitride semiconductor, which can be adapted to form an anti-surfactant film on a base body and form a nitride semiconductor layer by crystal growth from an opening portion formed in the anti-surfactant film, and a nitride semiconductor device formed by using the vapor-phase growth method.
In recent years, nitride based III–V compound semiconductors, such as GaN, AlGaN and GaInN, have become a focus of attention. This is because such a semiconductor has a forbidden band width ranging from 1.8 eV to 6.2 eV, and therefore, the semiconductor theoretically allows realization of a light emitting device enabling emission of light ranging from red light to ultraviolet light.
In the case of fabricating a light emitting diode (LED) or a semiconductor laser by using a nitride based III–V compound semiconductor, it is required to form a structure in which multi-layers, such as a GaN layer, an AlGaN layer, a GaInN layer, and the like, are stacked such that a light emitting layer (active layer) is sandwiched between an n-type cladding layer and a p-type cladding layer. In some cases, such a light emitting diode or a semiconductor laser includes a light emitting layer having a quantum well structure composed of GaInN/GaN or GaInN/AlGaN.
A vapor-phase growth technique for a nitride semiconductor, such as a gallium nitride based compound semiconductor, can be problematic because it can be difficult to obtain a substrate that is lattice matched with a nitride semiconductor or a substrate having a low density of dislocations. To solve such a problem, there is known a technique of depositing a low temperature buffer layer made from Aln or AlxGa1-xN (0≦x<1) at a low temperature of 900° C. or less on a surface of a substrate made from sapphire or the like, and then growing a gallium nitride based compound semiconductor thereon, thereby reducing dislocations due to lattice mismatching between the substrate and the compound semiconductor. Such a technique has been disclosed, for example, in Japanese Patent Laid-open No. Sho 63-188938 and Japanese Patent Publication No. Hei 8-8217. By using such a technique, it is possible to obtain a gallium nitride based compound semiconductor with improved crystallinity and morphology.
Another technique of obtaining a high quality crystal structure at a low density of dislocations has been disclosed, for example, in Japanese Patent Laid-open Nos. Hei 10-312971 and Hei 11-251253. This method involves depositing a first gallium nitride based compound semiconductor layer, forming a protective film made from a material capable of inhibiting growth of a gallium nitride based compound semiconductor, such as silicon oxide or silicon nitride, in such a manner as to selectively cover the first gallium nitride based compound semiconductor, and growing a second gallium nitride based compound semiconductor in an in-plane direction (lateral direction) from regions, not covered with the protective film, of the first gallium nitride based compound nitride layer, thereby preventing propagation of through-dislocations extending in the direction perpendicular to the interface of the substrate.
A further technique of reducing a density of through-dislocations has been disclosed, for example, in a document (MRS Internet J. Nitride Semicond. Res. 4S1, G3. 38 (1999)). This method involves growing a first gallium nitride based compound semiconductor, selectively removing the thus formed semiconductor film by using a reactive ion etching (hereinafter, referred to as "RIE") system, and selectively growing a second gallium nitride based compound semiconductor from the remaining crystal in the growth apparatus. According to this method, it is possible to obtain a crystal film having a density of dislocations, which is reduced to about 106/cm2, and hence to realize a high life semiconductor laser using the crystal film formed according to this method.
By the way, in the case of growing a gallium nitride based compound semiconductor layer by such a selective growth technique, a selective growth portion has a three-dimensional structure called "facet" having a tilt plane which is a stable plane growing at a low crystal growth. For example, in the case of forming an underlying layer on a sapphire substrate with a C-plane of sapphire taken as a principal plane of the substrate, covering the surface of the underlying layer with a silicon oxide film as an anti-surfactant film (growth-inhibiting film), and selectively growing a gallium nitride layer from an opening portion provided in the silicon oxide film by supplying a source gas, crystal growth portion has a pyramid shape, for example, a hexagonal pyramid shape having a tilt plane covered with a crystal plane, such as an S-plane.
In this case, however, since a crystal growth rate is generally low at the tilt plane, a supplied source of a group III element is not deposited but migrated at the tilt plane. On the contrary, at a top portion of the pyramid shaped crystal growth layer, since the supplied amount of the source becomes excessively large, the crystal growth rate becomes significantly high. As a result, the top portion of the crystal growth layer contains a number of defects such as point defects, that is, has poor crystallinity. Further, crystal growth at the top portion of the crystal growth layer does not result in a smooth surface, and accordingly, in the case of fabricating a semiconductor device having an active layer or a pn-function particularly on the top portion, performances of the semiconductor device are significantly degraded.
A need, therefore, exists to provide improved nitride semiconductors that can be readily made and effectively used in a variety of applications.

Vapor-phase growth method for a nitride semiconductor and a nitride semiconductor device


Calls redirected off-net, which includes call forwarding and call coverage, is provided at the switch to which the call is initially directed (the principal party's switch), by monitoring the redirected off-net connection with a call classifier and listening for the appearance of ringback tone and the appearance of voice frequency energy. The call is allowed to be completed to the off-net covering end-point if voice frequency energy is detected before ringback tone appears or if voice frequency energy appears within a predetermined time-out interval. If ringback tone continues beyond a time-out interval, if voice-frequency energy is not detected within the time-out interval, or if a call progress tone other than ringback is detected, further processing of the call is continued at the principal party's switch to determine if another covering point is listed. If no other coverage point is listed, monitoring of the call continues until the calling party hangs up. A simulated bridged appearance is maintained at the originating switch to allow the call to be picked up at the covered station at any time.

Call redirection, which includes call forwarding and call coverage from one endpoint to another, is a common feature of many telecommunications switches, particularly private branch exchanges (PBXs). An illustrative implementation of a call coverage feature is described in U.S. Pat. No. 4,436,962. Over time, efforts have been made to extend features across entire networks of routing nodes (e.g., switches) to make features that work with intra-node calls also work with inter-node calls. This is illustrated, for example, in U.S. Pat. No. 4,488,004. The call coverage feature has been a specific focus of some of these efforts, as illustrated by U.S. Pat. Nos. 5,313,459 and 5,369,695, for example.
Call redirection typically provides a covered end-point with the option of specifying a sequence of alternative end-points (also called covering end-points) to which the call may be directed if it cannot successfully be completed to the first or any subsequent covering end-point in the list of covering end-points stored in memory, i.e., the coverage path. However, when the coverage path specifies a covering end-point that is served by another switch, such as an end-point reached by using the public switched network, the switch to which the call was initially directed (hereinafter, the principal's switch), normally relinquishes control of the call to the other switch. Therefore, if the principal's switch redirects a call for coverage to a covering remote end-point but the end-point is unable to accept the call, the principal's switch is not able to regain control of the call and redirect it to the next covering end-point specified in the coverage path. This is especially true when the covering switch is in the public telecommunications network or when the switches do not have a cooperating protocol in place.
Heretofore it has been appreciated that if there is a common channel signaling network linking the switches it may be employed to allow the subsequent covering switch to inform the previous (e.g., covered) switch whether or not the call can be completed and, if not, the first switch may resume call coverage.
Another approach is disclosed in the copending application of D. W. Herrick et al, U.S. Pat. No. 5,521,970 in which the switch originally handling the call determines whether the covering switch to which the call would be redirected is a "cooperating switch", i.e., one which has been configured to effect network call coverage like the original switch and with which it can exchange signaling control information, sometimes hereinafter referred to as "DCS". If the covering switch is not a "cooperating" switch, the first switch relinquishes control to the covering switch. If the covering switch is a "cooperating" switch, the first switch sends a data message to the covering switch identifying the call as a network coverage call, the second switch determines whether it has a call-covering end-point available to receive the call, signals that fact to the first switch and simultaneously rings the call-covering end-point. If the call covering end-point was not available at the end-point, the first switch resumes control of the call.
While the ability to immediately complete the call to the covering end-point in the above-identified Herrick et al patent avoided the problem of the covering end-point becoming unavailable, it would be extremely advantageous if call coverage could be performed "off-net", i.e., when the call covering end-point is located beyond the direct reach of the first switch to which the call was initially directed, without requiring a signaling channel between the two switches handling the call. In addition, it would be helpful if a call could be extended using any type of available voice-frequency or ISDN type trunk path linking the switches.


Disclosed is an air conditioner with an enhance efficiency. The air conditioner An air conditioner includes: an indoor part for inhaling indoor air to exchange heat with an indoor heat exchanger, and again discharging the heat-exchanged air into an indoor space; an outdoor part for inhaling an outdoor air to exchange heat with an outdoor heat exchanger, and again discharging the heat-exchanged air into an outdoor space; a base partitioned into the outdoor part and the indoor part and loaded on the partitioned outdoor part and indoor part; and a cabinet provided to cover both sides and a rear surface of the outdoor part, and having an insertion guide formed at a lower portion thereof.

1. Field of the Invention
The present invention relates to an air conditioner, and more particularly, to an air conditioner provided with a curtain assembly for shielding a chink between the air conditioner and the window when the air conditioner is installed.
2. Discussion of the Related Art
Generally, air conditioner is installed at a window or the like of a building to air-condition an inner space of the building.
FIG. 1 is a perspective view illustrating appearance of a conventional air conditioner, and FIG. 2 is a perspective view illustrating an inner construction of a conventional air conditioner.
As shown in FIGS. 1 and 2, the conventional air conditioner includes a bottom base 1 of metal. Both sides and upper surface of the air conditioner are covered with a cabinet 3. The cabinet 3 has both lower ends coupled with both ends of the base 1, and an inner space for installing a variety of devices therein. An outdoor vent louver 4 formed at predetermined portions of the cabinet 3 functions as a passage through which outdoor air is inhaled into the inside of the outdoor part of the air conditioner.
The air conditioner includes a front panel 5 at a front surface thereof, and the front panel 5 includes a vent grill 7. The vent grill 7 functions as a passage through which indoor air is inhaled into the inside of the indoor part of the air conditioner. The front panel 5 has a discharge grill 9 at one side thereof. The heat-exchanged air in the air conditioner is discharged to an indoor space through the discharge grill 9. A filter is provided at a rear side of the vent grill 7 so as to purify the inhaled air.
An indoor heat exchanger 13 for exchanging heat with the air that has passed through the filter is installed at a rear side of the filter 11. The indoor heat exchanger 13 is installed at an air guide 15 mounted on the base 1. The air guide 15 guides indoor side airflow within the air conditioner. Further, the air guide 15 partitions the inside of the air conditioner into the indoor part and the outdoor part in case a separate barrier is not used. An orifice 16 guides the air that has passed through the indoor heat exchanger 13 to an indoor fan 19.
At a rear side of the air guide 15, i.e., at the outdoor part of the air conditioner, a motor 17 is provided. The motor 17 has a rotary shaft extended in bi-directions. One end of the rotary shaft penetrates the air guide 15 to extend to the indoor part, and the other end extends in an opposite direction. The indoor fan 19 is installed at the one end extending to the indoor part, and an outdoor fan 21 is installed at the other end of the rotary shaft. The indoor and outdoor fans 19 and 21 allow the airflow of the indoor part and the air of the outdoor part respectively.
To guide the airflow of the outdoor part, a shroud 23 is installed at the base 1. The shroud 23 has a space for installing the outdoor fan 21 therein to allow air to flow from one side to the other side of the space partitioned by the shroud 23. An outdoor heat exchanger 24 is installed at a rear space partitioned by the shroud 23. Accordingly, if a compressor 25 is driven, the outdoor heat exchanger 24 is heat-exchanged with the outdoor air introduced into the outdoor part through the vent louver 4. A separate discharge grill (not shown) is installed at a backside of the air conditioner to constitute the backside appearance of the air conditioner, and serves as a passage through which air that has passed through the outdoor heat exchanger 24 is discharged to the outdoor space.
In the meanwhile, a guide rail 27 is disposed on the cabinet 3. In installing the air conditioner at a window, a curtain assembly 30 for shielding a chink between the air conditioner and the window is coupled with the guide rail 27.
The curtain assembly 30 includes a curtain frame 32 having a section shaped in a '' and a curtain 34 provided within the curtain frame 32 to shield the chink. An installation plate 33 is provided on the curtain frame 32 to fix the curtain assembly 30 to the window and at the same time to shield a chink between the curtain frame 32 and the window. One end of the curtain 34 in a horizontal direction is fixed to an inner portion of the curtain frame 32 and the other end is coupled to a side surface of the cabinet 3 by a screw. Accordingly, the curtain 34 has a screw coupling hole 35 at the other end thereof.
The guide rail 27 is disposed on the cabinet 3 and beneath the base 1 to guide movement of the curtain frame 32.
According to the conventional art, one end of the upper portion and one end of the lower portion in the curtain frame 32 are inserted into the guide rail 27 to be movable in a horizontal direction. Accordingly, the insertion length of the curtain frame 32 into the guide rail 27 is varied depending on the interval size between the window and the air conditioner.
However, the conventional air conditioner having the aforementioned construction has the following drawbacks.
The outer case is generally made of metallic material and is installed such that its lower portions of both sides are coupled with the base 1 on which parts of the air conditioner are equipped. Accordingly, to maintain and repair parts of the inside of the air conditioner, there is a drawback in that all the outer case 3 should be separated from the air conditioner. Also, in case the conventional air conditioner is large-sized, there is a drawback in that handling work such as carrying work is difficult.
Also, since the outdoor vent louver 4 is formed only at a part of the outer case 3, the amount of inhaled outdoor air is relatively small. To this end, there is caused a problem in that heat exchange in the indoor heat exchanger is not smooth.
In the meanwhile, the guide rail 27 is provided on the cabinet 3 and beneath the base. In other words, the guide rail 27 is exposed to the indoor space to injure the appearance of the air conditioner. Also, there is a problem in that air is leaked through a gap generated between the guide rail 27 and the window in the vertical direction.
In addition, since the guide rail 27 is fabricated after the cabinet 3 and the base 1 are fabricated, there is a problem in that the number of work processes is increased.


An agricultural baler for picking up crop material and forming it into a rectangular shaped package, having a main frame, and an engine mounted on the main frame for operating the baler. The engine includes a throttle, and remotely located controls for changing the condition of the throttle between idle and full open to selectively operate the baler plunger rate from the cab of the towing vehicle, e.g., a tractor or a pickup truck. A control system for the throttle utilizes an electric reversible directional motor assembly having input terminals and an output shaft rotatable at a predetermined speed and direction under conditions where a predetermined voltage at a predetermined polarity is applied across such input terminals. Rotation of the output shaft is translated to pivotal motion of a lever that is coupled to the throttle.

Agricultural balers are implements that pick up crop material, such as straw or hay, from a windrow or swath lying on the ground, deposit it in an infeed housing where it is conveyed by a feeding mechanism through an inlet to a bale forming chamber. In the bale forming chamber the crop material is compressed by a reciprocating plunger to form a rectangular package of compacted crop material that is automatically tied by a tying mechanism to complete the bale that is then discharged rearwardly from the baler. Completed bales are either deposited on the ground for subsequent retrieval or they are transferred by appropriate means to a trailing wagon hitched to the baler. An attachment for throwing the bales into the wagon is one commonly known expedient.
Balers, usually towed behind a tractor, are either powered by an engine mounted on the baler, or by a drive shaft coupled to the PTO of the tractor to which the baler is hitched. Balers are also sometimes towed by a pickup truck and powered by an engine on the baler. It is not uncommon to control and monitor various baler functions from the tractor, and in the case of engine powered balers, the controls for certain engine functions are also remotely accessed. Among such remotely controlled engine functions is engine speed, which in the past has been changed from idle to baling speed by various remote systems. Engine speed is determinative of the strokes per minute of the baler plunger that has an optimized rate for normal operating conditions. A large majority of balers being used today are running at 90 strokes per minute, especially balers in the larger categories, e.g., a rectangular cross section of 15 inches by 22 inches. In some smaller categories, it is not uncommon for the plunger to be running at 70 strokes per minute.
In prior art remote control systems for baler engines, the same general result has been achieved by arrangements for varying engine speed, i.e., the engine throttle is changed from full open to idle positions for operational and idle baler modes, respectively. Applicant is aware of a system in which a cable is used for physically shifting the position of the baler engine throttle via means at a remote location, such as a pivoting lever arm mounted in a convenient location in the cab of the tractor or pickup truck that is towing the baler. It is not uncommon for problems in a system of this nature to reside in the mechanical cable assembly, which by its very nature is vulnerable to damage caused by bending and twisting. Additionally, as a result of the damp and dusty environmental conditions prevalent in the field, the elements of the cable system are also vulnerable to rust and buildup of unwanted crop residue and debris, both of which situations can lead to serious malfunctioning of the baler.
Another well known control system of the same general type is illustrated in U.S. Pat. No. 3,022,622, issued Feb. 27, 1962 in the name of E. B. Nolt, and assigned to the predecessor company of the assignee of the present invention. This patent discloses a system in which a mechanical linkage arrangement is utilized to pivot the throttle between open and closed positions. The position of the baler windguard, which is indicative of the existence of a substantial amount of crop material being picked up, ultimately controls the position of the throttle, i.e., when the wind guard is raised by crop material the throttle is pivoted to its full open position, and when the windguard is lowered in response to minimal crop material being picked up the throttle is closed to the idle position.
In another prior art system a switch is employed to remotely control the position of the throttle by stroking a solenoid that either extends or retracts an actuator arm for operating a linkage assembly. Again, the throttle is either in the fully open operating position or reversed to the closed position with the engine either at normal running speed or at low idle, respectively.
While the performance of all the aforementioned systems is generally satisfactory, there is always a continuing need to optimize the performance and reliability of farm implements. To this end, applicant has provided a unique solution to the above mentioned environmental and mechanical problems encountered by prior art systems.


The present invention relates to devices and systems for collecting and storage of solar energy, wherein the system for storing and retrieving captured temperature based energy comprising: one or more thermal collectors (5, 60), an energy carrier (29), a piping system (3, 7, 34, 35, 36), pumping device for controlling the flow of the energy carrier (29), and one or more ground thermal storage systems (30).

The present invention relates to devices and systems for collecting and storage of solar energy. Solar thermal collectors are normally classified as low, medium, or high-temperature collectors. Low-temperature collectors are flat plates generally used to heat swimming pools. Medium-temperature collectors are also usually flat plate which are used for heating water or air for residential and commercial use. High-temperature collectors concentrate sunlight using mirrors or lenses and are generally used for fulfilling heat requirements up to 300° C./20 bar pressure in industries, and for electric power production.
Seasonal thermal energy storage (or STES) is storing of heat or cold for periods of up to several months. The thermal energy can be collected whenever available and be used whenever needed, such as in the opposing season. For example, heat from solar collectors or waste heat from air conditioning equipment can be collected during "hot" months, for space heating use when needed, the winter season included. Waste heat from industrial process can similarly be stored and be used much later. STES stores can serve district heating systems, as well as single buildings or complexes. Among seasonal storages used for heating, the design peak annual temperatures generally are in the range of 70 to 80° C., and the temperature difference occurring in the storage over the course of a year can be several tens of degrees. Some systems use a heat pump to help charge and discharge the storage during parts or all of the cycle. For cooling applications, often only circulation pumps are used.
Examples of district heating include Drake Landing Solar Community where ground storage provide 97% of yearly consumption without heat pumps, and Danish pond storage with boosting. The Drake Landing Solar Community is a planned community in Okotoks, Alberta, Canada, equipped with a central solar heating system and other energy efficient technology. This heating system is the first of its kind in North America, although much larger systems have been built in northern Europe. The 52 homes in the community are heated with a solar district heating system that is charged with heat caught by solar collectors on the garage roofs and is enabled for year-round heating by underground seasonal thermal energy storage (STES).
The system was designed to model a way of addressing global warming and the burning of fossil fuels. The solar energy is captured by 800 solar thermal collectors located on the roofs of all 52 houses. It is billed as the first solar powered subdivision in North America, although its electricity and transportation needs are provided by conventional sources. LNG is used to cover peak heating demands.
In 2012 the installation achieved a world record solar fraction of 97%; that is, providing that amount of the community's heating requirements with solar energy over a one-year time span.
The Borehole Thermal Energy System (BTES) is located underground to store large quantities of heat collected during the summer to be used in the winter. It consists of 144 boreholes, which stretch to a depth of 37 m (121 ft). At the surface the pipes are joined together in groups of six to connect to the Energy Centre. The entire BTES is covered by a layer of insulation, on top of which the park is built. When the heated water is to be stored, it is pumped through the pipe series. The heat is then transferred to the surrounding soil as the water cools and returns to the Energy Centre. When the homes need heat, water flows to the center of the BTES field and picks up the heat from the surrounding soil. The heated water then goes to the short-term energy tank in the Energy Centre and is pumped through the District Heating Loop to the homes.
There are several shortcomings in the present technology related to BTES and STES. One technical problem is that there are considerable requirements to equipment needed in the processing phase when adapting the energy to specific needs of the user community. The requirements for advanced processing facilities means that there are limited benefits for a smaller community or single household other than when being part of a network connected to the network and/or the heat requirements are solely for house temperature control.
Another technical problem with current systems is that they provide heating only. As seen in the use of heat pumps is that instead of being a source for energy savings, they are in the hot months of the year used as coolers, and the end result is that a house equipped with heat pumps uses more energy for heating/cooling than a house relying on traditional heating systems such as electrical heaters. It is thus a problem with present available BTES and STES that they can supply heating but not cooling.
Chlorofluorocarbon, CFC, was for a long time the compound used as refrigerant in applications needing cooling, such as in refrigerators. EU agreed to ban production of CFC by the end of the century (2000). Alternative compounds have been developed, but there is a continuous struggle to develop new chemical compounds for replacing the CFC as refrigerants. Hydrofluorocarbons has taken over much of the ozone damaging CFCs compounds, but these again are believed to have a certain global warming potential, and are likely to be regulated or even banned in future.
It is further a technical problem that the solar thermal collectors are expensive, often based on a reflector or covering plate to reduce energy losses caused by wind, and piping system for maximizing the heat transferred to an array of piping leading to and from a heat storage. A problem is that they are only adapted to process the heating effect of the sun. The installations are vulnerable to the effect of snow and ice, and expensive to maintain and repair.
It is also a problem in current product offerings of solar thermal collectors that they are less effective than desired, since much of the potential heat collecting is lost due to the direct exposure to weather and wind.
A problem with thermal collectors are that a lot of harvesting hours are lost because of the equipment is covered by snow or frost.

System for storing and retrieving thermal energy


An actuator latch apparatus for a disk drive. The latch apparatus includes a metal piece disposed at one end of the swing arm, an attracting part protruded from an edge of the yoke, for attracting the metal piece by a magnetic force of the magnet, a hole formed at a position corresponding to the metal piece of the attracting part, for leaking magnetic flux flowing through the attracting part, a core disposed to move through the hole, and a core transfer device for transferring the core in one direction such that a leading end portion of the core is inserted into the hole when the disk drive operates, and for transferring the core in an opposite direction such that the core is released from the hole when the disk drive is stopped. Accordingly, a locking state of the actuator can be maintained more stably and released more easily.

1. Field of the Invention
Embodiments of the present invention relate to a disk drive, and more particularly, to an actuator latch apparatus and a disk drive, with the same, locking an actuator in a predetermined position when a disk is not rotating, such that the actuator is prevented from arbitrarily rotating, e.g., due to an impact.
2. Description of the Related Art
A hard disk drive (HDD) is one of the data storage devices of a computer. The HDD reproduces data from a rotating disk and records data on the disk with a read/write head. In such an HDD, the read/write head reaches a desired position while moving above a recording surface of the rotating disk by way of an actuator and then executes the reproducing/recording functions.
Meanwhile, when the HDD is not operating, that is, when the disk is not rotating, the read/write head is parked off the recording surface of the disk in order to prevent a collision with the recording surface of the disk. Such head parking systems can be classified into a contact start-stop (CSS) system and a ramp loading system. In the CSS system, a parking zone in which data is non-recordable is provided along an inner circumference of the disk and the read/write head is parked in close contact with the parking zone. In the ramp loading system, the read/write head is parked on a ramp, which is installed along the outside the disk.
When the read/write head is parked on the parking zone or the ramp, the disk may randomly rotate, e.g., due to an impact or vibration, such that the read/write head is forced out of the parking zone or the ramp and onto the recording surface of the disk. In this case, the read/write head can make forceful contact with the recording surface of the disk, such that the read/write head and the recording surface may be damaged. Therefore, when the read/write head is parked on the parking zone or the ramp, the actuator should be locked in a predetermined position so that it cannot rotate arbitrarily. For this purpose, various kinds of actuator latch apparatuses have been provided in the HDD field.
FIG. 1 is a plane view schematically showing a HDD having a CSS head parking system according to the related art, FIG. 2 is a partial exploded perspective view of the HDD shown in FIG. 1, and FIG. 3 is a side view of a voice coil motor (VCM), illustrating an actuator latch apparatus according to the related art.
Referring to FIGS. 1 and 2, the HDD includes a disk 20 for recording data, a spindle motor 30 installed on a base member 10 to rotate the disk 20, and an actuator 40 provided with a read/write head 41. The read/write head 41 reads data from the disk 20 and writes data on the disk 20.
There are usually one or more stacked disks 20, with an evenly spaced relationship therebetween, and with the spindle motor 30 rotating the one or more disks 20. The disk 20 can be provided with a parking zone 21 along an inner circumference of data zone 22. When power is off, a slider 42 mounted with the read/write head 41 can be stably parked on the parking zone 21.
The actuator 40 is provided with a swing arm 46 that has a pivot hole 48, in a central portion thereof, such that the actuator 40 can be mounted rotatably about a pivot 47 installed on the base member 10. A suspension 44 is mounted on one end of the swing arm 46 to elastically bias the slider 42 toward a surface of the disk 20, in which the read/write head 41 is mounted on the slider 42.
A voice coil motor (VCM) 50 rotates the actuator 40. The VCM 50 includes a VCM coil 56 coupled to the other end portion of the swing arm 46, magnets 53 and 54 respectively positioned above and under the VCM coil 56, facing the VCM coil 56, a lower yoke 51 on which the magnet 53 is attached, and an upper yoke 52 on which the magnet 54 is attached. Screws 59 secure the lower and upper yokes 51 and 52 to the base member 10.
When the data recording and reproducing operations are executed, two forces, a lift force generated by the rotation of the disk 20 and an elastic force of the suspension 44, act on the slider 42, such that the slider 42 is lifted above the data zone 22 of the disk 20, with a height at which the lift and elastic forces are balanced, thereby allowing the read/write head 41 to read/write data from/to the rotating disk 20 while maintaining a predetermined distance therebetween.
Meanwhile, since the lift force lifting the slider 42 disappears when the HDD is powered down, such that the disk 20 is not rotating, the slider 42 must be taken from the data zone 22 before the lift force disappears, in order to prevent the data zone 22 from being damaged by coming into contact with the slider 42. In other words, if the VCM 50 rotates the swing arm 46 of the actuator 40 to move the slider 42 to the parking zone 21, before the rotation of the disk 20 stops, the slider 42 can be parked at the parking zone 21 when the disk 20 stops, thereby preventing damage of the data zone 21.
Referring to FIGS. 2 and 3, the HDD can be provided with an actuator latch apparatus that locks the actuator 40 to prevent rotation thereof after the slider 42 is parked on the parking zone 21 of the disk 20. That is, when the power is off, the actuator latch apparatus prevents the actuator 40 from arbitrarily rotating, e.g., due to an impact or vibration, such that the read/write head 41 can be prevented from escaping from the parking zone 21 and moving onto the data zone 22.
The actuator latch apparatus is a magnetic latch apparatus that uses the magnetic force of the magnet, 53 and 54. The actuator latch apparatus includes a metal piece 65 installed in an end of the swing arm 46 and an attracting part 66 formed in the upper yoke 52, for attracting the metal piece 65 with the magnetic force.
The installation structure of the metal piece 65 includes a protrusion 62 formed on the end of the swing arm 46, a damper insertion hole 63 formed through the protrusion 62 in a horizontal direction, a damper 64 securely inserted in the damper insertion hole 63, and the metal piece 65 attached on an end of the damper 64. The damper 64 decreases the amplitude of any impact generated when the metal piece 65 collides with the attracting part 66.
The attracting part 66 protrudes from an edge of the upper yoke 52 and is bent downward to meet a top surface of the lower yoke 51. A slot 67 can be formed in the attracting part 66, at a corresponding position to the metal piece 65, with a predetermined width. The magnets 53 and 54 can generate magnetic flux in the attraction part 66. Herein, a magnetic flux leakage takes place at the slot 67 and the magnetic flux leakage causes the metal piece 65 of the swing arm 46 to stick on the attracting part 66, thereby locking the actuator 40.
When the power is off, the metal piece 65 is caused to come into contact with the attracting part 66 by the magnetic force, such that the actuator 40 can be locked. Herein, a large latch force is suitable to prevent the attached metal piece 65 from being detached from the attracting part 66, e.g., due to an impact. Meanwhile, when the power is on, the actuator 40 also has to be unlocked to move the read/write head 41 to the data zone 22 of the disk 20. Herein, a small latch force would be suitable to easily detach the metal piece 65 from the attracting part 66.
However, if the actuator latch apparatus is designed to have the large latch force for a reliable locking of the actuator 40, a large torque has to be impulsively exerted on the actuator 40 in order to detach the metal piece 65 of the swing arm 46 from the attracting part 66, and therefore, available maximum current flows through the coil 56 coupled to the swing arm 46 to generate the large torque. However, because of the inertia force of the large torque, the swing arm 46 rotates fast enough that it collides with a stopper (not shown), even after the metal piece 65 of the swing arm 46 is detached from the attraction part 66, causing a "head slap" to occur. The head slap is a phenomenon in that the read/write head 41 of the actuator 40 collides with the surface of the disk 20, e.g., by an impact or vibration, such that the head slap can cause damage to the read/write head 41 or the surface of the disk 20. Therefore, to prevent the head slap, a brake needs to be applied to the swing arm 46 immediately after the detachment of the metal piece 65 and the attracting part 66. However, it is very difficult to control servo current, for applying the brake to the swing arm 46.
Thus, to provide a stable and reliable locking and unlocking operation of the actuator, there is required an improved actuator latch apparatus, in which a large latch force is applied when locking the actuator and only a small latch force needs to be applied when unlocking the actuator.

Disk drive actuator latch apparatus and method


The present invention provides an apparatus and method of transmitting and switching multimedia data over an Ethernet network. The method includes allocating a portion of an Ethernet bandwidth for channel allocation, receiving a multimedia signal, assigning a channel allocation priority to the multimedia signal, transmitting data including the channel allocation priority in the allocated portion of the Ethernet bandwidth, performing video predictive coding on the multimedia signal to create a video predictive coded multimedia signal, and transmitting the video predictive coded multimedia signal over the network in real time. The multimedia signal comprises a composite video signal.

1. Field of Invention
The present invention is directed to an apparatus and method for transmitting, receiving, and switching multimedia across an Ethernet network.
2. Description of Related Art
Presently, audio and video are transmitted over various mediums for various purposes. These purposes include security transmissions, class lecture transmissions (distance learning), business seminar transmissions, surgical procedure transmissions, video conferencing transmissions, and the like. For example, security cameras are stationed at various remote locations in a building. The security video from the cameras is transmitted over dedicated lines and switches to a security station to monitor activity at the remote locations. Quite often the buildings having such security systems also have local area data networks such as Ethernet networks for transmitting data. Unfortunately, two separate systems must be used for the security and data network systems because of problems encountered in combining the systems.
In particular, security video is time sensitive and encounters unacceptable delays when transmitted on a data network. Additionally, data networks do not provide adequate bandwidth for transmitting uncompressed real time continuous video. Thus, the transmission of video across a data network requires extensive compression. Unfortunately, such compression is slow, complex, and/or prohibitively expensive for security systems, or the like. Furthermore, data networks do not prioritize video data. Therefore, the video data is often broken up and suffers considerable delays. Similar problems are encountered in the transmission of lectures, seminars, video conferencing, and other like real time video transmissions. Thus, independent networks must be maintained for uncompressed real time continuous video transmission and for data transmission because combining the transmissions is ineffective and/or cost prohibitive.

Uncompressed IP multimedia data transmission and switching


When a target image with an aspect ratio of 4:3 is displayed on the screen A of the PDP26 with an aspect ratio of 16:9, the rectangular black images on the left and right of the target image are not solid black. Instead, the luminance of the rectangular black images is lowered stepwise as it becomes more distant from the boundary of the target image, and finally reduced to substantially zero, or to a black image at a position away from the boundary to some extent. This prevents the luminance from sharply falling from the boundary and edge from causing due to the addition of the rectangular black image, thereby preventing burning on a part of the screen A corresponding to the position of the boundary.

(1) Field of the Invention
The present invention relates to a plasma television and image display device capable of displaying an image different in aspect ratio from a display screen thereon.
(2) Description of Related Art
An image display device is known as prior art for example disclosed in the following document, that corrects the luminance level of video display signals displayed on a display screen between a display and a non-display area based on the correction data when a partial screen display mode is switched to a whole screen display mode (refer to Japanese Patent Laid-Open No. 2004-144819).
In the above patent document, no measures to prevent burning occurring in the partial display mode have been taken. This virtually allows burning on a screen attributed by a partial display.
In the document, a video display signal itself is corrected to change its luminance in the whole screen display mode. For this reason, atmosphere of an image such as brightness of the image may be displayed differently from an original intention of the inputted video display signal.

Plasma television and image display device


Approaches provide for monitoring attempted network activity such as network port connections and corresponding payloads of network data obtained by a network device and, based on the attempted connections and/or payloads, identifying malicious network activity in real time. For example, network activity obtained from a plurality of network devices in a service provider environment can be monitored to attempt to detect compliance with appropriate standards and/or any of a variety of resource usage guidelines (e.g., network behavioral standards or other such rules, guidelines, or network behavior tests) based at least in part on network port connection activity with respect to at least one network device. If it is determined that network activity is not in compliance with the usage guidelines, or other such network behavior test, the system can take one or more remedial actions, which can include generating a notification identifying the malicious network activity.

As an increasing number of applications and services are being made available over networks such as the internet, monitoring these networks is important to ensure reliable operation, fault detection, timely mitigation of potentially malicious activities, etc.
Many networks rely on network monitoring systems such as a honeypot network to monitor inbound internet traffic. These network monitoring systems collect network data and analyze the network data for information about attacks and other anomalous activities.
Conventional network monitoring systems typically require manually analyzing network data for information about malicious activity. Manual analysis can be time-consuming and inefficient. Further, manual analysis is susceptible to human error. Moreover, manual analysis can result in delays, as malicious behavior is identified only after it is discovered.
A need exists, therefore, for systems, methods, and devices that overcome this disadvantage.


This invention provides the preparation of water-dispersible polyester/acrylic hybrids via a two-stage emulsion polymerization process. For example, methacrylic acid and/or 2-hydroxyethyl methacrylate are copolymerized with styrene/acrylic monomers to yield a relatively hydrophilic and hydro-plasticized first stage. Subsequent additions of hydrophobic monomers to this first stage "seed" results in an inversion of the latex such that the more hydrophilic first stage is at the particle surface. This results not only in improved stability of the resulting latex without the use of additional surfactants, as evidenced by the production of reduced amounts of coagulum, while it also offers relatively low minimum filming temperatures due to the hydroplasticization of the shell of the particle. Furthermore, the use of the water-dispersible polyester results in extremely fine latex particle sizes which can significantly enhance coating properties such as film gloss and clarity.

The particle size of a latex can often have a direct impact on the performance of a coating prepared from that latex. Among those properties that can be affected are gloss, clarity, film formation, and substrate penetration (i.e., for porous substrates). In a very general sense, a smaller particle size will have a positive effect on such properties. Small particle sizes (i.e., <100 nm) are most often achieved by using relatively high levels (2-4 wt) of small molecule, typically anionic, surfactants such as AEROSOL-OT, sodium dioctyl sulfosuccinate and AEROSOL NPES 2030, ammonium nonylphenoxy polyethoxy ethanol sulfate, which are anionic surfactants sold by Cytec Industries, Inc. However, small particle size and the properties directly affected by it are not the only important properties in water-based coatings. Of primary importance is the water-resistance/sensitivity of the final film. In small particle size systems, the high level of anionic surfactant, the very component in the latex which gives the small particle size and all of its concommitant advantages, is also likely to be detrimental to water-resistance.
One further challenge in the preparation of any stable latex is production of a stable emulsion with minimal amounts of coagulum. As noted in Emulsion Polymers and Emulsion Polymerization, "The Formation of Coagulum in Emulsion Polymerization", by J. W. Vanderhoff, 1981, American Chemical Society, coagulum, i.e., polymer recovered in a form other than that of a stable latex, is produced in all sizes of reactors and poses several problems. Such problems include loss of yield of the desired latex, processing difficulties due to the necessity of clean-up, more batch-to-batch variation in latex properties, and health, safety, and environmental problems insofar as the coagulum must be disposed of; this is made more problematic due to entrapment within the coagulum of toxic monomers such as vinyl chloride and acrylonitrile. According to this reference, the formation of coagulum is due to either a failure of the colloidal stability of the latex during or after polymerization, which leads to flocculation of the particles or by polymerization of the monomer(s) by mechanisms other than by the intended emulsion polymerization.
U.S. Pat. No. 5,342,877 describes a method for preparing small particle size latexes via copolymerization of hydroxyalkyl (meth)acrylates (15-40 weight percent based on total latex solids) and other vinyl/acrylic monomers (particularly styrene) in the presence of water-dispersible polyesters.
U.S. Pat. No. 4,939,233 describes a method for preparing water-dispersible polyester/vinyl acetate copolymer blends via emulsion polymerization using sulfonated polyesters as stabilizers in the reaction.
U.S. Pat. Nos. 4,946,932 and 5,277,978 describe a methods for preparing water dispersible polyester/-acrylic copolymer blends via emulsion polymerization in the presence of sulfonated polyesters as stabilizers.
U.S. Pat. No. 5,156,651 describes water dispersible polyester/vinyl aromatic latexes for textile sizing applications.
U.S. Pat. No. 4,839,413 describes the use of low molecular weight (i.e., less than 20,000) alkali-soluble resins as "support resins" in emulsion polymerization. The support resin is formed via non-aqueous polymerization methods and is subsequently dispersed/dissolved in alkaline solution. The emulsion polymerization is then carried out, at high pH, in the presence of this dissolved support resin and an additional costabilizer (surfactant). A pH of greater than 8 is taught to be necessary.
U.S. Pat. No. 5,326,843 describes a process for preparing low molecular weight (i.e., less than 40,000) alkali-soluble polymers via emulsion polymerization. Unsaturated aromatic monomers (e.g. styrene), methacrylic acid, and low pH (less than 4.5) are specifically taught.
U.S. Pat. No. 4,325,856 describes the preparation of a multistage latex in which the first stage is more hydrophilic (via incorporation of acid functional monomers) than the second stage thereby resulting in an inverted core-shell morphology. Typical anionic surfactants such as potassium n-dodecyl sulfate, sodium isooctylbenzene sulfonate, sodium laurate, and nonylphenol esters of polyethylene glycols are used to stabilize the latexes. Latex particle sizes of 130-160 nm are reported. Unlike the methodology taught in U.S. Pat. No. 4,839,413, complete neutralization of the acid-functional first stage is not necessary.
U.S. Pat. No. 4,150,005 describes the preparation of a multistage latex in which the first stage is more hydrophilic than the second stage, thereby resulting in an inverted core-shell morphology. Typical small molecule anionic surfactants such as alkali metal and ammonium salts of alkyl, aryl, alkaryl, and aralkyl sulfonates, sulfates and polyether sulfates, and corresponding phosphates and phosphonates, and ethoxylated fatty acids, esters, alcohols, amines, amides and alkyl phenols, are used to stabilize the latexes. As with the methodology described in U.S. Pat. No. 4,325,856, complete neutralization of the first stage is not necessary. Furthermore, combinations of methacrylic acid and hydroxyethyl methacrylate as hydrophilic components of the first stage are claimed as is a range of hydrophilic copolymer of 20-80 wt % of the total latex. The advantages of using the hydroplasticized first stage to lower minimum filming temperatures are also described.
U.S. Pat. No. 4,916,171 describes technology very similar to that described in U.S. 4,150,005 with the exception that the only hydrophilic monomers claimed are carboxylic acids. A much broader range for the hydrophilic polymer of 1-99 wt % of the total latex is claimed. This reference also teaches that the hydrophilic shell polymer has a very high Tg (>100.degree. C.) and that the most preferred range of hydrophilic polymer is 40-60 wt % of the total latex.
J. Appl. Polymer Sci., 44, 1075 (1992) (M. Lambla et al.) describes the terpolymerization of styrenelbutyl acrylate/methacrylic acid in the presence of low levels of sodium dodecyl sulfate, a small molecule surfactant, with the subsequent copolymerization of styrene/butyl acrylate in the presence of the acid functional latex. Inverted core-shell latexes (i.e. acid functional 1st stage at particle surface) with average particle sizes of 250 nm resulted from this method. As with U.S. Pat. No. 4,839,413 described above, high pH is a critical part of the process for preparing these materials.

Small particle size polyester/acrylic hybrid latexes


A combination measuring tool includes a main body having a first portion having a plurality of first graduations and a second portion having a plurality of second graduations, a transverse bar movably and rotatably mounted on the main body and having a semi-circular protrusion having a plurality of angle scales, a protractor secured to the transverse bar and having a plurality of angle scales, a pivot plate pivotally mounted on the protractor, and a ruler movably mounted on the main body and having a plurality of graduations. Thus, the measuring and drawing angle of the combination measuring tool can be adjusted easily and freely, thereby facilitating a user operating the combination measuring tool to draw marking lines.

1. Field of the Invention
The present invention relates to a measuring tool and, more particularly, to a combination measuring tool having the function of a ruler, protractor and the like.
2. Description of the Related Art
A conventional ruler is used to measure the distance of an object. Thus, when a user wishes to connect rafters and posts to build a wooden house, the ruler is used to measure the distance and draw marking lines on the rafters and the posts to form mortises and tenons on the rafters and the posts by sawing so as to connect the rafters and posts by mortising. However, the ruler cannot measure or draw an oblique angle so that the ruler needs aid of other tool, such as a protractor or setsquare, to draw angled marking lines, thereby causing inconvenience to the user. In addition, the ruler cannot be used to form chamfered corners on the rafter and to form breaches in stairs, thereby limiting the versatility of the ruler.

Three-dimensional combination measuring tool


A device including a first discharge passage from a first rotor assembly to an engine, a first return passage that returns to an intake side of the first rotor assembly, a second discharge passage from a second rotor assembly to the engine, a second return passage that returns to an intake side of the second rotor assembly, and a pressure control valve whose valve main body is provided between a discharge port from the second rotor assembly and the first discharge passage. The first discharge passage and the second discharge passage are coupled, and a flow passage control is executed in each of: a low revolution range; an intermediate revolution range; and a high revolution range.

1. Field of the Invention
The present invention relates to an oil pump pressure control device that facilitates a reduction in friction while maintaining characteristics identical to the pressure characteristics of a common oil pump based on the provision of a plurality of discharge sources and a newly devised method of switching oil passages.
2. Description of the Related Art
While a variable flow rate oil pump of the conventional art comprises two discharge ports configured from a single discharge port partitioned into two, because of the single rotor assembly thereof, from the viewpoint of the discharge source there is still a single discharge port. In addition, at times of high revolution when the amount of power consumed by the pump is high, oil passages of a main pump (first pump) and a sub-pump (second pump) are in communication. Accordingly, the pressure of the main pump is substantially equivalent to the pressure of the sub-pump. Although reference is made herein to a main pump and a sub-pump, obviously these pumps constitute a single pump (a single rotor), and little or no reduction in superfluous work, should it occur, can be achieved using a single pump. Furthermore, because the discharge passage of the sub-pump terminates within a valve, there is a limit to the flow rate regulation afforded by the valve alone.


Techniques for using call history for voice data over a packet-switched network includes receiving call history data that indicates a redirected network identity that served as a target of a particular voice data session from a particular calling party. The redirected network identity is different from both a caller network identity that identifies the particular calling party, and a current target network identity that identifies a current target party of the particular voice data session. A call history display composition is formed that indicates at least that the redirected network identity exists. The call history display composition is presented for viewing by at least one of the particular calling party and the current target party. These technique allow a party to redirected communications to easily call or save the network address of a former target of the call.

1. Field of the Invention
The present invention relates to communicating voice data over a packet-switched network with a telephone set for use by a human; and, in particular relates to displaying, for use by the human user of the telephone set, call history data resident in a protocol for setting up such voice communications, such as in the Session Initiation Protocol (SIP) for voice over the Internet Protocol (IP).
2. Description of the Related Art
Networks of communications devices and general-purpose computer systems connected by external communication links are well known and widely used in commerce. The networks often include one or more network devices that facilitate the passage of information between end stations, such as telephones and general purpose computing devices, which originate or receive the information. A network node is a network device or end station connected by the communication links. Information is exchanged between network nodes in discrete data packets according to one or more of many well known, new or still developing protocols. In this context, a protocol consists of a set of rules defining how the nodes interact with each other based on information sent over the communication links. The protocols are effective at different layers of operation within each network node, from generating and receiving physical signals of various types, to selecting a link for transferring those signals, to the format of information indicated by those signals, to identifying which software application executing on a computer system sends or receives the information. Signaling between nodes is typically effected by exchanging special data packets called control plane data packets. Each data packet typically comprises 1] header information associated with a particular protocol, and 2] payload information that follows the header information and contains information that may be processed independently of that particular protocol. Often, the data in the payload for the particular protocol includes a header and payload for a different protocol associated with a different, usually higher layer protocol. The payload protocol is said to be encapsulated in the header protocol.
Commercial services that provide voice data communicated over a packet-switched network predominately use the Internet Protocol (IP) as the internetworking layer protocol to communicate with devices on different networks. A voice data session over IP between end stations is set up predominately using IP datagrams that include in the IP payload the Session Initiation Protocol (SIP) header and payload. The SIP header provides information about the party that originated the voice data, e.g., a caller network identifier ("caller ID") and the called party, e.g., a target network identifier ("target ID").
Many telephone sets, including wireless mobile telephone sets, have displays that indicate the other party engaged in the voice communications. For example, the telephone set of the called party displays the caller ID and the telephone set of the calling party displays the target ID. Many of these sets store one or more caller IDs or target IDs and allow a human user to access them immediately or at some later time (e.g., to support redial functions). While suitable for many purposes, there are an ever-growing set of circumstances in which this information is inadequate for one or the other of the calling parties, or both.
For example, a human user named Mary uses a voice over IP (VoIP) telephone set (setA) to call a second VoIP device (setB) that is used to provide technical support. The SIP header shows the target ID is setB. That set is an application that automatically routes the call to an available technician. The call is redirected to a third VoIP telephone set (setC) used by a technician named Jane. The SIP header is changed to show the new target ID is setC. After Jane and Mary converse for awhile, Mary asks a question better answered by a third party, named Paul, who uses a fourth VoIP telephone set (setD). Jane transfers the call to Paul. The SIP header is changed to show the new target ID is setD. After Mary and Paul converse, Mary determines that she has another question for Jane. However, the target ID for Jane is no longer displayed on Mary's setA, only the target ID for Paul. Paul does not know Jane's number; and his setD shows only Mary's caller ID. Mary can only call the technical support application (setB) and hope she is redirected to Jane again, an unlikely occurrence. Similarly, if Paul is interested in how Mary's call came to him, e.g., because Paul's network identity is not public, and if Mary is not forthcoming with the information, Paul is unable to determine that Jane directed the call to him. The problem is compounded if Mary's call is redirected a number of times before the current target of her call.
Based on the foregoing, there is clear need for techniques that allow end users to determine temporary targets of calls routed over IP and redirected to another target. In particular, there is a need for techniques to display the existence of temporary targets of a redirected call, or use information related to the temporary targets, or both.


The components of a multiphase converter, which contains semiconductor power components and a capacitor on a support containing cooling devices, are arranged in an optimally compact configuration, in which the support containing the cooling device is configured as a hollow body, the capacitor is or the capacitors are insertable in its interior in as tightly and precisely fitted fashion as possible, and the semiconductor power components are arranged on its outer side, where the height of the hollow body corresponds substantially to the height of the necessary capacitor. For a three-phase converter, the hollow body may be in the shape of a hexagon on the outer side, so that an overall shape approximating a cylinder is created, and a cylindrical cover protects everything and makes a compact component available, and for a two-phase converter, a parallelepipedal volume is optimally utilized.

The present invention is based on a multiphase converter having semiconductor power components and a capacitor.
In multiphase converters that are equipped with semiconductor power components and a capacitor, a so-called buffer capacitor, in particular a high-power electrolytic capacitor, at least those components may be mounted on a support containing cooling devices. Supports that may be used may on the one hand be flat, rectangular cooling boards which contain cooling ducts through which a liquid coolant flows. Flat, rectangularly shaped supports on one of whose sides the components are attached, and on the other of whose sides cooling fins or cooling ribs are provided for air cooling, may also be used. Since, in higher-power converters, a very large capacitor may need to be provided as a so-called buffer capacitor, for which an electrolytic capacitor may be used, the overall height perpendicular to the support is determined by its relatively large height, and the extension in area of the support is determined both by the base outline of the capacitor and also, additively, by the relatively large power semiconductor attachment surfaces that need to be cooled. As a result, it is believed that a converter of this kind may require considerable space both in area and in terms of height. This space requirement may not be available in every application.
An object of an exemplary embodiment of the present invention is to arrange the components in such a way that considerably less space should be required as compared to the design and manner of arrangement discussed above.
The arrangement according to the exemplary embodiment of the present invention of the components of a converter is believed to have the advantage, as compared to the design and manner of arrangement discussed above, of requiring substantially less room for the same power, and also of ensuring substantially more-intensive cooling of the capacitor. It is believed that the exemplary embodiment packs the components compactly together with substantially improved space utilization. It is also believed that a given volume of space, especially substantially in cylindrical form, and the cooling system, are optimally utilized.
In the arrangement according to the exemplary embodiment of the present invention of a multiphase converter, for that purpose the support is configured as a hollow body; the capacitor or an arrangement of capacitors connected in parallel is provided insertably, in as tightly and precisely fitted fashion as possible, in its interior; and the semiconductor power components are arranged on its outer side. The semiconductor power components are thus arranged around the capacitor as center, separated by the cooling element functioning as support.
According to another exemplary embodiment of the present invention, the hollow body is configured in such a way that it has on the outer side a substantially cylindrical or parallelepipedal configuration, and on its inner side a cylindrical configuration or a configuration adapted to the external shape of the capacitor arrangement. As a further improvement to this configuration, the hollow body is equipped on its outer side with suitable surfaces on which the semiconductor power components can be mounted in good thermally conductive contact with the coolable hollow body.
In another exemplary embodiment of the present invention, which is believed to make available a particularly simple and clearly organized construction, the hollow body is equipped with flat surfaces, and flat outer surfaces are provided, in particular four in the case of two-phase converters, and six in the case of three-phase converters. The components belonging to one half or one third of a bridge can thus be arranged in very clearly organized and attractive fashion, in the form of a parallelepiped or in approximately cylindrical form, around the cooling support, while the capacitor or capacitor arrangement sits in the center and can also be cooled. This compact arrangement is believed to be further improved since the hollow body is substantially of a length in the axial direction that corresponds to the length of the capacitor or the capacitor arrangement.
In another exemplary embodiment of the present invention, a parallelepipedal or cylindrical cover is provided which occludingly surrounds the hollow body serving as support, together with the components mounted in and on it, except for necessary connecting contacts. The components are thereby protected from influences acting from outside, and a self-contained, ready-to-install, and very compact component is thus made available.
According to another exemplary embodiment of the present invention, the hollow body also serves as a support for electrical boards. According to one exemplary embodiment, for example, electrical activation boards for the semiconductor power components are provided on the outer side of the semiconductor power components and their electrical connecting lines. In an exemplary embodiment, electrical control boards can be provided and mounted on one or both end faces of the hollow-body-shaped support.
In another exemplary embodiment of the present invention, the hollow body is equipped with suitable and suitably arranged cooling ducts; a coolant, in particular a liquid one, can be forced through those cooling ducts. In an exemplary embodiment, the hollow body is equipped at one end face with a support part containing cooling ducts through which cooling ducts provided in the outer support wall can be connected to one another, thereby imparting to the hollow body a cup-like shape. The capacitor provided in the interior is thus, very advantageously, surrounded over almost its entire exterior by the cooling hollow-body-shaped support.
The arrangement according to an exemplary embodiment of the present invention is believed to be, very usefully, usable in a variety of applications; it is provided and is believed to be suitable in particular for use in a motor vehicle or an electric vehicle or a hybrid vehicle or a starter-generator drive system.


A detector circuit for detecting a malfunction of a circuit due to a low third power supply voltage that has the same amplitude and potential as an input signal is provided. Based on an output signal of the detector circuit, whether an output of a second power supply voltage generation circuit for activating a heater driving circuit is allowed or not is determined. When the third power supply voltage is low and the heater driving circuit operates improperly, no power supply voltage is supplied from the second power supply voltage generation circuit. Since no power supply voltage is supplied to the heater driving circuit, the heater driving circuit does not drive a corresponding heater.

1. Field of the Invention
The present invention relates to inkjet printheads and printing apparatuses using the same. More particularly, the present invention relates to an inkjet printhead substrate on which electrothermal transducers for generating heat energy necessary for ejecting ink and drive circuits for driving the electrothermal transducers are formed, a printhead, and a printing apparatus using the printhead.
2. Description of the Related Art
In general, electrothermal transducers (heaters) of a printhead mounted in an inkjet-based printing apparatus and drive circuits for driving the electrothermal transducers are formed on one and the same substrate using a semiconductor processing technique, as described in, for example, U.S. Pat. No. 6,290,334. One proposed example of such a printing apparatus has a printhead in which an ink supplying port is provided near the center of a substrate, and heaters are provided at positions facing each other with the ink supplying port provided therebetween.
FIG. 1 schematically illustrates circuit blocks and ink supplying ports of an inkjet printhead substrate (element substrate) 110 of this type.
Referring to FIG. 1, six ink supplying ports 111 are formed on the element substrate 110 formed of semiconductor. In order to simplify the drawing, a circuit block 115 including only one ink supplying port 111 at the left is illustrated, and circuit blocks 115 corresponding to the remaining five ink supplying slots 111 are only schematically illustrated. In the circuit block 115 corresponding to the ink supplying port 111 at the left, heaters 112 are arranged in an array at positions facing each other with the ink supplying port 111 provided therebetween. Drive circuits 113 for selecting and driving the corresponding heaters 112 are provided corresponding to the heaters 112. Pads 114 for applying power and signals to the heaters 112 and the drive circuits 113 are arranged at edges of the element substrate 110.
FIG. 2 schematically illustrates the circuit structure of one drive circuit 113 shown in FIG. 1 and the flow of a signal.
Data including image data applied to the pads 114 is connected to a shift register 204 and a decoder 205 included in an internal circuit via an input circuit 201. In this example shown in FIG. 2, the input data is applied as serial data, and the serial data is converted into parallel data by the shift register 204. The image data included in the converted parallel data is input via a latch (not shown) to a plurality of heater driving blocks 206 (eight heater driving blocks 206 are arranged in this example). The shift register 204 has the function of a block selecting circuit 203 for selecting the validity/invalidity of the heater driving blocks 206. Another portion of the converted parallel data is supplied to the decoder 205 disposed next to the shift register 204. The decoder 205 has the function of a time-division selecting circuit 202 for outputting a time-division selection signal for sequentially selecting heaters driven in the heater driving blocks 206.
FIG. 3 is a circuit diagram of the interior of one heater driving block.
A heater driving block 300 includes heater-driving metal-oxide semiconductor (MOS) transistors 305, level conversion circuits 304, and heater selecting circuits 305, which are arranged corresponding to heaters 306 arranged in an array. A heater power supply voltage (first power supply voltage) is applied from the outside to heater power supply lines 301. The heater-driving MOS transistors 305 perform the function of a switch for allowing or preventing the flow of current to the corresponding heaters 306. A block selection signal 302 and a time-division signal 303 are input to an AND gate serving as each of the heater selecting circuits 305. When these two signals become active, the output of the AND gate becomes active. The voltage amplitude of an output signal of the AND gate is converted by a corresponding one of the level conversion circuits 304 to a power supply voltage (second power supply voltage) that is higher than a drive voltage (third power supply voltage) at a level of a logic circuit including the input circuit and a corresponding one of the heater selecting circuits 305. The level-converted signal is applied to the gate of a corresponding one of the heater-driving MOS transistors 305. Current flows through the heater 306 connected to this heater-driving MOS transistor 305 in which the voltage has been applied to the gate thereof, thereby driving this corresponding heater 306.
The voltage amplitude of the output signal is converted to the higher second power supply voltage because of the following reason. By increasing the voltage applied to the gate of the heater-driving MOS transistor 305, the on-resistance of the heater-driving MOS transistor 305 is reduced. Accordingly, current can more efficiently flow through the heater 306.
If possible, the voltage value of the second power supply voltage should not exceed a circuit breakdown voltage and a gate breakdown voltage of the MOS, and the second power supply voltage should be set to as high a value as possible. Further, if possible, the voltage value of the second power supply voltage may be the same as the voltage value of the first power supply voltage, which is the voltage value of the heater power supply lines 301. In most cases, however, the power supply voltage applied to heaters is generally set to a relatively high value, such as 20 V or greater. In most cases, a complementary metal-oxide semiconductor (CMOS) inverter is generally processed to have a breakdown voltage of about 15 V. Since the gate breakdown voltage of a MOS depends on a gate oxide film, the gate breakdown voltage of the MOS must be sufficiently lower than the withstand voltage of the gate oxide film. It is therefore often difficult to match the optimal voltage of a voltage conversion circuit with a heater driving voltage. U.S. Pat. No. 6,971,735 describes an example in which a voltage input from the outside of a substrate is adjusted by making the thickness of a logic circuit on a printhead substrate thinner than the thickness of a heater driving section.
In this case, if a power supply line for supplying the second power supply voltage, which is different from the heater power supply voltage (first power supply voltage), is additionally provided, the cost of the overall system is increased.
In order to solve this problem, a power generation circuit for generating a desired second power supply voltage from a heater power supply voltage (first power supply voltage) is provided in the interior of a printhead substrate. An example of this type of circuit is described in Japanese Patent Laid-Open No. 11-129479. Furthermore, U.S. Pat. No. 6,712,437 describes an example of a circuit in which an input voltage VDD for a logic circuit is input to a heater-driving switching element. However, the description does not concern the relationship between a heater power supply voltage VH and a VDD circuit.
FIG. 9 illustrates an example of a power generation circuit.
The circuit shown in this example includes an nMOS transistor 803 and a resistor 804 constituting an nMOS source follower, and resistor dividers 801 and 802. The heater power supply voltage (first power supply voltage) is divided by the resistor dividers 801 and 802, and the divided voltage is applied to the gate of the nMOS transistor 803. An output of the source follower serves as the second power supply voltage. With the resistor dividers 801 and 802, the voltage applied to the gate of the nMOS transistor 803 can be set to a desired value. Accordingly, the second power supply voltage can be a voltage that is lower than the heater power supply voltage (first power supply voltage).
FIG. 5 is a circuit diagram of the internal structure of a level conversion circuit and its peripheral circuits. In FIG. 5, a heater-driving MOS transistor 505, a heater 506, a PMOS transistor 510, and an NMOS transistor 511 are shown.
A signal supplied from a heater selecting circuit is inverted by an inverter operating at the third power supply voltage to generate an inverted logic signal, and this generated signal is applied to the gate of an NMOS transistor and a PMOS transistor operating at the second power supply voltage. The transistors driven by the second power supply voltage need to be elements that can withstand the second power supply voltage.
As another circuit structure, a structure in which level conversion is performed immediately after an output of a shift register and a decoder is proposed.
FIG. 4 is a circuit block diagram of the structure in which level conversion is performed immediately after a shift register and a decoder.
Referring to FIG. 4, pads 401, a time-division selecting circuit 402, and a block selecting circuit 403 are shown. The point that is different from the foregoing circuit structure is that output signals of a shift register 404 and a decoder 405 are level-converted by level conversion circuits 411 and 412, respectively. Circuits driven by the third power supply voltage, which has the same voltage amplitude and the same potential as an input signal, are those enclosed by line 415. Circuit blocks driven by the second power supply voltage higher than the level-converted first power supply voltage are those enclosed by line 416. These circuit blocks enclosed by line 416 include heater driving blocks 406.
With this structure, it becomes unnecessary to dispose a level conversion circuit for each heater selecting circuit. Accordingly, the density of circuits near heaters become increased, and the layout area becomes reduced.
As has been described above, in circuits on an inkjet printhead semiconductor substrate, the third power supply voltage which has the voltage amplitude of an input signal and which activates logic circuit blocks is used. Further, the higher second power supply voltage applied to the gate of a MOS transistor, which is a switching element for controlling heater current, is used. The circuits are controlled and driven by these two power supply voltages. Further, an output signal of a drive circuit for supplying the third power supply voltage is converted by a level conversion circuit into a signal with the signal amplitude of the second power supply voltage.
The first and third power supply voltages are supplied from a printer body to the printhead semiconductor substrate. In most cases, the second power supply voltage is generated by converting the first power supply voltage via a power supply voltage generation circuit provided in the substrate to a voltage lower than the first power supply voltage.
The sequence of supplying these voltages to the printhead semiconductor substrate is such that, after the third power supply voltage is applied, the heater power supply voltage (first power supply voltage) is applied. This is because, if the heater power supply voltage (first power supply voltage) is applied in a state where no third power supply voltage is applied, the head may operate unexpectedly.
That is, in a state where the first power supply voltage is applied, the second power supply voltage is also applied inside the substrate. Therefore, the heater driving circuit including the level conversion circuit is enabled. In contrast, an input signal of the level conversion circuit is output from a circuit that operates based on the third power supply voltage. However, in a state where no third power supply voltage is applied, the logic thereof becomes indefinite. In this state, the logic of an output of the level conversion circuit becomes indefinite, which may result in the logic where an unexpected heater is turned on.
In order to avoid this indefinite logic state, it is necessary to supply the third power supply voltage and then the first power supply voltage, which is followed by generation of the second power supply voltage in the substrate. In order to apply the voltages in this sequence, special measures must be taken by the printer body, resulting in an increase in the cost.

Printhead substrate, inkjet printhead, and inkjet printing apparatus


A heating system includes a plurality of heater elements, a plurality of switches connected to the plurality of heater elements, a set of predetermined performance information including heater information specific for each heater element, at least one temperature sensor measuring temperature of at least one heater element from among the plurality of heater elements, and a heater control unit in communication with the temperature sensor(s). The heater control unit controls the heater elements differently, via the switches, based on the heater information and the measured temperature from the temperature sensor(s).

The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Heat flux is a useful measure for predicting relative heater element performance, including temperature, transfer efficiency, and life-time. The flux density exhibited by a heater element is defined as Watt density (watts/mm2), which represents a measure of the magnitude of the power that can be concentrated per square millimeter of an element's surface area. A heater element that exhibits a high Watt density will generally provide a fast temperature rise and a lower overall manufacturing cost due to the reduced amount of surface area that is required. However, these advantages are often off-set by the risk of reduced lifetime due to the higher surface temperatures that are encountered, as well as the potential for lower reliability (e.g., over-shooting the desired temperature condition, etc.).
During manufacturing, variances encountered in processing conditions and heater construction can result in differences in the heat flux that are exhibited within different portions of a single heater element or between the various heater elements that are produced. In order to compensate for this manufacturing variability, and ensure reliability at the expense of maximizing performance (e.g., rate of heating) and minimize cost (e.g., lowering the element's surface area), the industry conventionally applies a safety factor, which results in a reduction in the Watt density exhibited by the heater element.


The invention relates to a hybrid phase plate for use in a TEM. The phase plate according to the invention resembles a Boersch phase plate in which a Zernike phase plate is mounted. As a result the phase plate according to the invention resembles a Boersch phase plate for electrons scattered to such an extent that they pass outside the central structure (15) and resembles a Zernike phase plate for scattered electrons passing through the bore of the central structure. Comparing the phase plate of the invention with a Zernike phase plate is has the advantage that for electrons that are scattered over a large angle, no electrons are absorbed or scattered by a foil, resulting in a better high resolution performance of the TEM. Comparing the phase plate of the invention with a Boersch phase plate the demands for miniaturization of the central structure are less severe.

In a Transmission Electron Microscope (TEM) a beam of electrons produced by an electron source is formed into a parallel beam of electrons illuminating the sample. The sample is very thin, so that part of the electrons pass through the sample and part of the electrons are absorbed in the sample. Some of the electrons are scattered in the sample so that they exit the sample under a different angle than under which they enter the sample, while others pass through the sample without scattering. By imaging the sample on a detector, such as a fluorescent screen or a CCD camera, intensity variations result in the image plane. The intensity fluctuations are in part due to the absorption of electrons by the sample, and in part to interference between scattered and unscattered electrons. The latter mechanism is especially important when observing samples in which little electrons are absorbed, e.g. low-Z materials such as biological tissues.
The contrast of the image resulting from electrons interfering with each other can, for parallel illumination, be explained as follows:
A parallel illumination can be described in Fourier space as a distribution δ(G) where δ denotes the well-known Dirac delta function which is only non-zero at G=0, and G denotes spatial frequency. The scattering of the incoming beam is described by the specimen function φ(G). The beam Ψ0(G) immediately after the specimen becomesΨ0(G)=δ(G)−iφ(G)  [1]The imaging system, and in particular the objective lens of the TEM, aberrates this wave toΨ(G)=δ(G)−iφ(G)exp[2πiχ(G)]  [2]where χ(G) is the aberration function which depends on parameters like defocus and spherical aberration. The intensity at the detector is equal to the convolution of Ψ(G) with its complex conjugate Ψ(G)*,|(G)=Ψ(G)*Ψ*(G)  [3a]This can be written as|(G)=δ(G)−iφ(G)exp[2πiχ(G)]+iφ*(−G)exp[−2πiχ(−G)]+φ(G)exp[2πiχ(G)]*φ*(−G)exp[−2πiχ(−G)]  [3b]As in Fourier space both frequencies G and −G are present, and since φ(x) is a real function, φ*(−G) can be replaced with φ(G).φ*(−G)=φ(G)  [4]Similarly, since χ(G) is even in G, χ(−G) can be replaced with χ(G).χ(G)=χ(−G)  [5]The expression for the intensity simplifies to|(G)=δ(G)−2φ(G)sin [2πiχ(G)]+φ(G)exp[2πiχ(G)]*φ(G)exp[−2πiχ(G)]  [6]The factor sin [2πiχ(G)] is called the Contrast Transfer Function (CTF):CTF(G)=sin [2πiχ(G)]  [7]The term quadratic in φ(G) is small and is usually neglected.
Objects with a specific spatial frequency scatter the beam over a specific angle, the scattering angle being proportional to the spatial frequency. For low spatial frequencies the scattering angle is close to zero and the contrast is close to zero as χ(G) and consequently the CTF is almost zero. For higher spatial frequencies the contrast fluctuates due to the positive and a negative values for the CTF, depending on the spatial frequency. As the CTF is close to zero for low spatial frequencies, large structure cannot be resolved in the image.
In 1947 Boersch described that the introduction of a phase plate would result in a CTF where low spatial frequencies show a maximum, and large structures can thus be imaged, see "Über die Kontraste von Atomen im Elektronenmikroskop", H. Boersch, Z. Naturforschung 2A (1947), p. 615-633. Recently such phase plates have successfully been introduced in TEM's.
A phase plate is a structure that is placed in a plane where the beam illuminating the sample, after having passed through the sample, is focused to a spot by the so-named objective lens.
It is noted that a phase plate can also be placed in a plane that is an image of the plane where the objective lens focuses the beam to a spot.
Usually, the illuminating beam is a parallel beam, and then the plane where the beam is focused to a spot is the back-focal plane of the objective lens. If the illuminating beam is not a parallel beam, but close to parallel, then this plane is close to the back-focal plane of the objective lens or close to an image of said plane. In the plane of the phase plate all unscattered electrons are focused in one point, while scattered electrons are imaged at other positions. The phase plate causes a phase shift θ between scattered and unscattered electrons. Therefore equation [2] is modified toΨ(G)=δ(G)−iφ(G)exp[2πiχ(G)+θ]  [8]and thus equation [7] toCTF(G)=sin [2πiχ(G)+θ]  [9]By choosing θ=π/2 (or more general: θ=π/2+2nπ, with n an integer), this reduces toCTF(G)=cos [2πiχ(G)]  [10]thereby converting the sine-like behaviour of the CTF to a cosine-like behaviour. It is noted that a phase shift of θ=−π/2 also causes a cosine-like behaviour of the CTF. It is further noted that a marked improvement of the contrast may also occur for phase shifts other than θ=π/2+nπ.
For a more detailed derivation of the formulae the reader is referred to "High-resolution electron microscopy", J. C. H. Spence, 3rd edition (2003), ISBN 0198509154, more specifically to paragraph 3.4 and chapter 4.
In a so-named Boersch phase plate such a phase shift is caused by temporary accelerating or decelerating the unscattered electrons.
A Boersch phase plate must have a very small diameter to allow (most of the) scattered electrons to pass without intercepting these scattered electrons by the physical structure of the phase plate. The manufacturing of such a phase plate is described in e.g. U.S. Pat. No. 5,814,815 to Hitachi.
The known phase plate comprises a grounded ring-like structure with an inner electrode, thus resembling a miniature electrostatic Einzellens. The electrons passing through the phase plate are temporarily accelerated or decelerated. By a proper choice of the voltage on the inner electrode the phase shift θ of the electrons is e.g. plus or minus π/2. The electrons that are passing outside the miniature lens do not experience the phase shift. By positioning the phase plate in a plane where the beam illuminating the sample is focused to a point and centering it round the axis of the objective lens, the unscattered electrons experience the phase shift, while all electrons that are scattered pass outside the phase plate and thus do not experience the phase shift.
A problem of the known phase plate is that the central structure intercepts electrons, thereby blocking electrons scattered over a small angle. These electrons are necessary to image structures with a low spatial frequency. Large structures can thus not be imaged with such a phase plate.
It is noted that any scattered electrons that also pass through the phase plate, because they are scattered over a very small angle, will experience the same phase shift as the unscattered electrons and can thus not interfere with the unscattered electrons to form a high contrast image.
A disadvantage of the known phase plate is that large structures can not be imaged as the scattered electrons carrying the information with low spatial resolution are either blocked by the physical structure of the phase plate or experience the same phase shift as the unscattered electrons. This makes it difficult to navigate to points of interest in the sample, or to observe the position of a high resolution feature, such as a lipid bi-layer, in a large feature, such as a cell.
It is noted that another type of Boersch phase plate is described in International Application WO2006/017252 to Glaeser. This phase plate comprises a central ring electrode surrounded by a grounded ring electrode. Herewith an electric field can be generated on the axis, thereby accelerating or decelerating the unscattered electrons, while the grounded electrode acts as a shield so that scattered electrons do not experience a phase shift. The disadvantages mentioned for the phase plate of U.S. Pat. No. 5,814,815 are equably applicable.