A fluid rotary apparatus includes rotors accommodated in a housing, driving shafts on which the rotors are mounted, upper and lower bearings for rotatably supporting upper and lower portions of each of the shafts, fluid suction and fluid-discharging openings formed in the housing, motors adapted for independently and synchronously driving each of the shafts, rotation-detecting devices for detecting the rotational angle and/or the number of rotations of each motor, contact-preventing gears for contacting each other before the rotors contact each other, and a positive displacement pump structure section sucking and discharging fluid by utilizing a closed space formed by the rotors and the housing and controlling the motors in synchronous rotation thereof in response to signals outputted from the device. The housing includes, along the axial direction of the shaft, a first section accommodating the rotors, a second section accommodating the gears and the upper bears, a third section accommodating the lower bearings, a fourth section accommodating the motors and a fifth section accommodating the detecting device. The housing sections are capable of being disassembled by fixing members removably fixing the housing sections to each other and sealing members held between the housing sections.

The present invention relates to a fluid rotary apparatus, and more particularly to a fluid rotary apparatus suitable for allowing a vacuum pump to generate a vacuum in a wide range of vacuum pressures by discharging gas from a vacuum chamber installed in an apparatus for manufacturing semiconductors.
A vacuum pump for generating a vacuum environment is required by a CVD apparatus, a dry etching apparatus, a sputtering apparatus, an evaporating apparatus and the like for use in processes for manufacturing semiconductors. The vacuum pump is used also in processes of manufacturing magnetic disks and liquid crystal displays.
In recent years, a vacuum pump having a high operational performance has been more and more strongly demanded. In processes for manufacturing semiconductors, it has become desirable for circuits to be more and more highly integrated, for wafers to have larger diameters, for circuits to have large three-dimensional configurations, and for many kinds of semiconductors to be manufactured in small quantities. For high integration, clean equipment is required. Small equipment is necessary to provide wafers with large diameters. The equipment requires complex processing in multiple chambers so that the circuits can be large in three-dimensions. In order to manufacture many kinds of semiconductors in small quantities, equipment must have a network.
In order to comply with the above demands, it is necessary to prevent the vacuum pump from being polluted by oil, that the vacuum pump can generate a wide range of vacuum pressures, that the vacuum pump is corrosion-resistant, and that the vacuum pump has a high efficiency relative to the space it occupies.
Above all, the vacuum pump is required to generate vacuum pressures in a wide range. Although vacuum pressures as low as 10.sup.-8 to 10.sup.-10 torr have been required in recent years, one vacuum pump is incapable of generating such a high vacuum (i.e. low pressure). That is, in a positive displacement vacuum pump called a roughing rotary pump, two rotors synchronously rotate with a screw formed on the peripheral surface of each rotor engaging each other to generate a volume change in a closed space disposed between the screws. Gas is inhaled and compressed repeatedly to discharge the gas from the vacuum chamber by utilizing the volume change. This type of pump is suitable for discharging gas in the region of viscous flow, the pressure of which is near atmospheric pressure, but the pump operates in a pressure range from as high as atmospheric pressure to 10.sup.-3 torr. In a kinetic vacuum pump called a turbo pump, one rotor imparts momentum to gas molecules by its rotation so that the gas molecules are transferred by the momentum. As a result, gas is discharged from the vacuum chamber. The pump provides a vacuum pressure as low as 10.sup.-2 to 10.sup.-10 torr, but in principle, the pump is capable of discharging gas from the vacuum chamber in a molecular flow region, the vacuum pressure of which is lower than 10.sup.-1 torr and higher than 10.sup.-3 torr. In order to obtain a low vacuum pressure of 10.sup.-8 to 10.sup.-10 torr, it is necessary that a vacuum pressure of 10.sup.-2 to 10.sup.-3 torr is generated by the rotary pump such that a predetermined high (i.e. low pressure) vacuum is obtained by the turbo pump.
The use of two types of vacuum pumps leads to the installation of large equipment. That is, in order for equipment to carry out composite processing in multiple chambers, each chamber is required to be equipped with a vacuum apparatus. The use of two types of vacuum pumps for each chamber does not allow a vacuum discharge apparatus to be compact. Consequently, a space cannot be efficiently used and, in addition, the cost of equipment is high.

Housing arrangement for a synchronous plural motor fluid rotary apparatus

Matsushita Electric Industrial Co., Ltd.


This is an iontophoresis device preferred to detect abnormal conductivity at the beginning of energization and during energization. The iontophoresis device has a device (50) as a power source and the device (50) comprises an electric energy generating portion (60) generating electric energy, an output portion (70) outputting the electric energy, and an abnormal conductivity detecting portion (80) detecting whether or not the electric energy is supplied normally. The detecting action of the abnormal conductivity detecting portion (80) is carried out at the time of the non-output action of the output portion (70). During the energization, the output action by the output portion (70) and the detecting action by the abnormal conductivity detecting portion (80) are alternated in response to a command received from the microcomputer (12).

The iontophoresis is a system used for quickening skin absorption with electricity. The object of the iontophoresis is to quicken permeation of medicine molecules through the skin barrier with good use of a force that moves positively charged molecules from positive pole to negative pole and negatively charged molecules from negative pole to positive pole in an electric field generated mainly due to current conducting. [Refer to (Journal of Controlled Release) pp. 213 to 220, Vol. 18, 1992; Advanced Drug Delivery Review) p. 119, Vol. 9, 1992; Pharmaceutical Research) pp. 318 to 326, Vol. 3, 1986.]
Such an iontophoresis device having been known well is provided with means for checking whether or not the movement of molecules (including drugs) is done normally. The checking means in this case may be, for example, a method for measuring an output current with respect to a voltage output from an applied DC. According to this method, a conducting or non-conducting state is checked by applying a comparatively high voltage to the object spot at the beginning of energization. When the output current is in a predetermined value or less, it is decided as abnormal, thereby the voltage output stops.
The official gazette of National Publication of International Patent Application No. 10-510179 discloses a power-driven transportation unit used to monitor both current and voltage of the power-driven transportation. This transportation unit, when the impedance on the object human skin is stabilized for a predetermined time after the device is started up, begins monitoring of both current and voltage of the transportation. When the monitored value is not within a predetermined value, the output stops.
In case of the above described method that makes the monitoring by applying a comparatively high voltage to the object spot at the beginning of energization, however, a problem arises; concretely, the high output voltage makes the user feel malaise. In addition, the above described method which begins monitoring of both current and voltage of the power-driven transportation after the impedance on the object spot skin is stabilized is to be confronted with another problem that the current conducting state cannot be confirmed until the impedance on the object spot skin is stabilized.
Under such circumstances, it is an object of the present invention to solve the above conventional problems and provide an iontophoresis device preferred to detect abnormal conductivity at the beginning of energization and during energization.


An image transfer system, including a member for supporting print media, the member including a pair of sidewalls depending therefrom, a pair of end caps, wherein one end cap is connected to the sidewalls at an end thereof and the other end cap is connected to the opposite end of the sidewalls, and a heating element disposed against the underside of the member and in contact with each of sidewalls and end caps.

In the ink jet printing process, suitable support of the print media during printing aids in achieving acceptable print quality. Such support can include holding sheet media flat against a media supporting member, or platen, to ensure the ink maintains suitable properties during printing.
In addition, it may be desirable that a media sheet be heated uniformly as it rests on the printer platen, in order to achieve acceptable print quality. A technique, in pursuit of this goal, is to heat the platen to a suitable temperature. This is sometimes accomplished by the use of heating strips disposed against the sidewalls of the platen. While this technique results in effective heating of areas of the platen surface, it can fail in some instances to provide uniform heating over the platen surface. The result can be a diminution in print quality because of temperature gradients across the platen producing unevenly heated media sheets.
Where the term xe2x80x9cimage transfer systemxe2x80x9d is used in this description, the term is meant to encompass a variety of such devices, including printers, facsimile devices and scanners. For convenience, the term xe2x80x9cprinterxe2x80x9d will be used in this written description but it should be understood that the description is intended broadly, to cover such other devices.
Another factor adversely affecting print quality may be a failure to draw the media sheet against the platen in a uniform manner. This is especially the case at the ends of the platen where air passes under media edges, thereby tending to raise the media away from the platen
Airflow at the media edges allows cool air to pass under the edges as the air flows generally toward the center of the media for evacuation. This airflow can produce an uneven temperature distribution across the media as portions of the media are raised away from the heated platen. Again, the result adversely impacts print quality. In addition, if air flows freely under media edges, a potential develops whereby the edges lifting from the platen surface may contact printheads thereby causing print defects, paper jams and, in some cases, damage to the printer.
An image transfer system includes a member for supporting print media, the member including a pair of sidewalls depending therefrom, a pair of end caps, wherein one end cap is connected to the sidewalls at an end thereof and the other end cap is connected to the opposite end of the sidewalls, and a heating element disposed against the underside of the member and in contact with each of sidewalls and end caps.

Apparatus and method of supporting media in an image transfer system

Hewlett-Packard Development Company, L.P.


The invention relates to a push-in clamp retainer for an electric connector element with a lead wire receptacle which is at least partly encircled by a surrounding wall. In a lateral direction, a push-in clamp assembly includes such a push-in clamp retainer and a separate spring member having a first end and second end, The invention also relates to an electric connector element having a spring release member and a push-in clamp assembly. The invention involves the implementation of at least one receiving member into at least one contraction of the push-in clamp retainer, combining such a push-in clamp retainer with a spring member to form the push-in clamp assembly, and adding a spring release member to the push-in clamp assembly to obtain the electric connector element.

Such push-in clamp retainers, push-in clamp assemblies or electric connector elements are known in the art and are often fabricated using injection molding which requires the insertion of an additional electrically conducting element into a lead wire receptacle in order to allow an electrical contact by pressing the lead wire against the electrically conducting element. Furthermore, push-in clamp assemblies are known in the prior art whereas riveting or welding is used to attach the spring member to the push-in clamp retainer. Moreover, electric connector elements known from the prior art do not allow to compress and hold a spring member in an assembly position without additional means as for instance a screwdriver.
An electric connector element using a spring member to press a lead wire against an electrically conducting element is, for instance, known from the European Patent Application EP 2 325 947 A1. The disclosed electric connector element uses a lever to release a spring member or to exert force on a spring member in order to move said spring member out of or into the lead wire receptacle. If contacting of the lead wire with the electrically conducing element is initiated, the time it takes until full pressure of the spring member is applied to the lead wire, thus pressing the lead wire against the electrically conducting element, solely depends on the speed the lever is moved from an assembly position to an operating position. When applied with high voltage and/or current, arcing may occur between the lead wire and the electrically conducting element. Furthermore, the lever demands for a specially designed push-in clamp retainer and may completely prevent operation of the electric connector element if failure occurs to the lever.
Another exemplary electric connector element is known from the European Patent EP 1 515 397 B1. Such an electric connector element uses a specially-designed spring member, wherein a first end of the spring member is fed through an opening in a second end of the spring member increasing the complexity of the spring member.
Another electric connector element is known from the European Patent Application EP 2 768 0479 A1 and utilizes a simple spring member but requires an additional electrically conducting element, for instance a conductor rail placed in the lead wire receptacle.

Push-in clamp retainer, push-in clamp assembly and electric connector element


A color copying machine includes a plurality of image forming sections having rotatable photoconductive drums, respectively. One of the drums, which is used for forming images in black, is rotated by a first drum drive motor, and the other drums are rotated by a second drum drive motor. A plurality of transfer devices are arranged to oppose the image carriers, respectively. A paper sheet is sequentially moved to positions opposing the drums and clamped between the drums and transfer rollers so as to transfer images on the drum to the paper sheet. When a image formation is performed by using the image forming section for black, the first drive motor is operated and the second motor is stopped. The transfer rollers opposing the drums for other than black are moved to positions wherein these transfer rollers are away from the corresponding drums.

1. Field of the Invention
This invention relates to an electrophotographic image forming apparatus such as full color copying machines, color laser printers, and the like, and, more particularly, it relates to an image forming apparatus for forming images on a paper sheet by means of a plurality of photoconductive drums.
2. Description of the Related Art
Recently, digital full color copying machines have been developed and getting popularity on a demand for color images. As one of color copying machines, there is provided a Four-tiered photoconductive drum type full color copying machines which comprise four photoconductive drums. In this type of copying machine, four photoconductive drums are arranged in parallel with one another, and images in yellow, magenta, cyan and black are formed on the drums, respectively. A transfer material is carried by a conveyer belt and sequentially brought into contact with these drums, so that the toner images on the drums are transferred to the drums and overlapped with each other. Thus, a full color image can be obtained.
Upon forming an image other than a full color image by means of the copying machine, e.g., an image in black, toner images are not formed on the three drums for yellow, magenta, and cyan and only a black toner image is formed on the drum for black. Then, the black toner image is transferred to a transfer material, thereby obtaining a black image.
A problem with such a copying machine is that, even when a monochromatic image is formed, the drums and developing devices for the remaining three colors are also driven. In other words, the three drums and the associated developing devices that do not participate in forming a monochromatic image are unnecessarily and uneconomically operated. Thus, the drum surfaces are worn off by cleaning devices which are in contact with the drum surfaces, and the drums and the associated developing devices are fatigued as they contact with each other. Additionally, the developing sleeves of the developing devices may remarkably be worn and the toner may quickly be degraded as the sleeves are in contact with the toner.
In order to solve the above problems, Japanese Patent Application KOKAI Publication No. 63-8658 discloses an image forming apparatus in which only an image carrier and a developing device associated therewith used for image formation are driven and another image carriers and developing devices are stopped. However, this Publication does not concretely show drive means for driving the image carriers and the developing devices.
In Japanese Patent Application KOKAI Publication No. 4-76565 is disclosed an apparatus wherein selecting means for selectively driving a developing device is arranged on a drive shaft of an image carrier and the developing device is moved toward and away from the image carrier by the selecting means. However, in this apparatus, the image carrier is larger than that in the Four-tiered photoconductive drum type copying machine. Further, supporting members for the developing devices are rotated individually, thereby generating large vibrations and influencing formed images.
Japanese Patent Application KOKAI Publication No. 4-134463 discloses a mechanism for switching a transfer sheet clamp mechanism and a transfer roller. However, this mechanism is complex in structure and large in manufacturing cost.


An information recording and reproducing apparatus records data on and reproduces data from each of a plurality of recording layers of a recording medium. A controller (7) controls a formatting process to format the recording medium (1) by performing a first formatting process on the data area of a recording layer. The first formatting process comprises formatting the data area in a series of recording increments that progress from the inner side of the data area to the outer side of the data area. Within each recording increment the formatting is performed along a path extending from the outer side of the data area to the inner side of the data area. A second formatting process on the data area of another recording layer once the first formatting process has been completed, the second formatting process being performed along a path extending from the inner side of the data area of the other recording layer to the outer side of the data area of the other recording layer.

There is an information recording and reproducing apparatus that performs a so-called background formatting when, for example, formatting a DVD+RW disc which is a rewritable disc. In the background formatting, a notification of completion of formatting is sent to a host computer at a time when recording is performed on only a part of a lead-in area of the DVD+RW disc, and a remaining area is recorded by dummy data when there is no access request from the host computer. According to the background formatting, a formatting process time is greatly reduced.
Additionally, as another feature of the background formatting, there is an advantage that a disk can be ejected in the middle of a formatting process. At that time, in order to enable reproduction by a conventional reproduction only apparatus, when ejecting a disc in a middle of a formatting process, the disc is ejected after filling an unrecorded area of a data area with dummy data and recording a lead-in area and a lead-out area. Thus, logical compatibility of the disc, which is ejected in the middle of the formatting process, with a DVD-ROM can be maintained.
In recent years, a dual-layer DVD+RW disc (DVD+RW DL (Dual Layer) Disc), which has two recording layers, has been developed as a disc on which a large amount of data can be recorded. Accordingly, there has been developed an information recording and reproducing apparatus, which performs recording and reproduction with respect to the dual-layer DVD+RW disc (for example, refer to Japanese Laid-Open Patent Application No. 2004-303421).
The background formatting is also used for the dual-layer DVD+RW disc, similar to the DVD+RW disc having a single recording layer. That is, a part of a lead-in area is recorded for a request for formatting from a host computer, and a notification of completion of the formatting is sent to the host computer so as to enable an access by the host computer and user data is recorded from a data area of the first layer. Then, while there is no access request from the host computer, remaining areas from the first layer to the second layer are recorded with dummy data. Additionally, eject of the disc in the middle of formatting process is enabled.
However, when ejecting the dual-layer DVD+RW disc in the middle of a formatting process, data is recorded in a temporary middle zone (TMZ) immediately after recording end position of user data of the first layer and the data of the temporary middle zone is recorded immediately after a position corresponding to the user data recording end position in a data area of the second layer, and the disc is ejected after filling an unrecorded part of the data area of the second layer with dummy data so as to maintain compatibility with a DVD-ROM.
FIG. 1 and FIG. 2 are illustrations for explaining a process performed when ejecting a dual-layer DVD+RW disc in the middle of a conventional formatting process.
As shown in FIG. 1, after recording an initial zone 50 of a lead-in area, recording instructed by a host computer is permitted. Then, if a request of ejecting the optical disc is made when the user data 51 is recorded, data 52 of a temporary middle zone is recorded from the end of the recorded position of the user data 51 as shown in FIG. 2, and data 53 of the temporary middle zone is recorded immediately after a position corresponding to the above-mentioned user data recording end position in the second layer. Then, an unrecorded area 54 in the second layer is recorded with dummy data, and, thereafter, the lead-in area 55 and the lead-out area 56 are recorded and, then, the optical disc is ejected.
However, in the conventional information recording and reproducing apparatus, if a last recording position of user data or a format end position of a recording medium having two recording layers, an area in the second layer corresponding to the first recording layer must be recorded with dummy data when a request of ejecting the recording medium is made. Thus, there is a problem that it takes a considerably long time until the recording medium is ejected.

Information recording and reproducing apparatus and a method of controlling an information recording and reproducing apparatus


Semiconductor light emitting and sensing devices are comprised of a lattice matching wurtzite structure oxide substrate and a III-V nitride compound semiconductor single crystal film epitaxially grown on the substrate. Single crystals of these oxides are grown and the substrates are produced. The lattice matching substrates include Lithium Aluminum Oxide (LiAlO.sub.2), Lithium Gallium Oxide (LiGaO.sub.2), Lithium Silicon Oxide (Li.sub.2 SiO.sub.3), Lithium Germanium Oxide (Li.sub.2 GeO.sub.3), Sodium Aluminum Oxide (NaAlO.sub.2), Sodium Gallium Oxide (NaGaO.sub.2), Sodium Germanium Oxide (Na.sub.2 GeO.sub.3), Sodium Silicon Oxide (Na.sub.2 SiO.sub.3), Lithium Phosphor Oxide (Li.sub.3 PO.sub.4), Lithium Arsenic Oxide (Li.sub.3 AsO.sub.4), Lithium Vanadium Oxide (Li.sub.3 VO.sub.4), Lithium Magnesium Germanium Oxide (Li.sub.2 MgGeO.sub.4), Lithium Zinc Germanium Oxide (Li.sub.2 ZnGeO.sub.4), Lithium Cadmium Germanium Oxide (Li.sub.2 CdGeO.sub.4), Lithium Magnesium Silicon Oxide (Li.sub.2 MgSiO.sub.4), Lithium Zinc Silicon Oxide (Li.sub.2 ZnSiO.sub.4), Lithium Cadmium Silicon Oxide (Li.sub.2 CdSiO.sub.4), Sodium Magnesium Germanium Oxide (Na.sub.2 MgGeO.sub.4), Sodium Zinc Germanium Oxide (Na.sub.2 ZnGeO.sub.4) and Sodium Zinc Silicon Oxide (Na.sub.2 ZnSiO.sub.4). These substrates are used to grow single crystal epitaxial films of III-V nitride compound semiconductors with the composition Al.sub.x In.sub.y Ga.sub.1-x-y N 0.ltoreq.x.ltoreq.1, 0.ltoreq.y.ltoreq.1, and 0.ltoreq.x+y.ltoreq.1. The semiconductor light devices can also include mixed combinations of any two or more of the above listed compounds. Furthermore, the preferred lattice matching substrates can include all the above listed modified wurtzite structure oxide compounds and their mixed crystals with substitution of the following elements, Be, B, N, Cr, Mn, Fe, Co, Ni, Cu, In and Sb. With the exception of N which can partially replaces oxygen only, all the rest elements are able to replace partially the cations of the above mentioned wurtzite structure oxide compounds. The types of semiconductor light devices that use this invention include light emitting devices, laser diodes, optical pumped laser diodes and optical detectors such as photoluminescence sensors and photo detectors. The laser diode devices can include a lateral or vertical Fabry-Perot resonant cavity, with or without metal electrodes.

Compound semiconductor laser diodes (LD) based on III-V materials such as GaAs have been in use for more than three decades. Current available LDs emit typically in the near infra-red spectral region. The most common applications of these LDs are in two specific areas, the optical-fiber communications and the compact disk (CD) players and CD ROMs. Although the visible LED and LD are highly desirable, in many applications especially in the display areas, they are not available due to the band gap limitation of the existing III-V compound semiconductor materials. In the last few years, red LD based on the quaternary Al--Ga--In--P system has produced light in the spectrum range of 630 to 670 nm region. Table 1 lists the currently available semiconductor LDs and their emitting wavelengths. From Table 1, it is quite clear that two of the most important color sources, blue (.apprxeq.470 nm) and green (.apprxeq.550 nm), are not available.
TABLE 1 ______________________________________ Currently Available Semiconductor Laser Diodes and Their Emitting Wavelengths: Compound Emitting Wavelengths (.mu.m) ______________________________________ AlGaInP 0.65-0.68 Ga.sub.0.5 In.sub.0.5 P 0.67 Ga.sub.1-x Al.sub.x As 0.63-0.90 GaAs 0.90 In.sub.0.2 Ga.sub.0.8 As 0.98 In.sub.1-x Ga.sub.x As.sub.y P.sub.1-y 1.10-1.65 In.sub.0.73 Ga.sub.0.27 As.sub.0.58 P.sub.0.42 1.31 In.sub.0.58 Ga.sub.0.42 As.sub.0.9 P.sub.0.1 1.55 InGaAsSb 1.7-4.4 PbEuSeTe 3.3-5.8 PbSSe 4.2-8.0 PbSnTe 6.3-29 PbSnSe 8.0-29 ______________________________________
To achieve the blue and green LED and LD emissions, it has been necessary to use direct bandgap compound semiconductor materials with band gap sufficiently wide enough (>2-3 eV) to generate the blue or green transitions as shown in FIG. 1. Since the traditional semiconductor materials such as GaAs and InP do not have a sufficiently wide enough bandgap, one approach is to use the so-called wide-bandgap II-VI semiconductor materials such as ZnSe which has a band gap of 2.3 eV. The reason to use ZnSe is that its lattice matches reasonably well to that of GaAs and Ge so thin epitaxial thin films can be made using these readily available commercial substrates. However, the production of blue and green emissions is far from easy. It was not until 1991 with the combination of the development of multi-layer quantum-well heterostructures by the Molecular Beam Epitaxial (MBE) technique and the successful achievement of p-type doping using nitrogen make the fabrication of the injection laser device possible. At present the II-VI LD devices are fabricated on GaAs substrate with ZnMgSSe optical-cladding layers and ZnSSe waveguiding regions and two to three ZnCdSe quantum wells. The LD has operated successfully in cw (continuous wave) mode at 470 nm in liquid nitrogen temperature and at 508 nm at room temperature. Unfortunately the lifetime of cw room temperature operation is very short, and is typically less than one hour. This short lifetime is due to both the high ohmic contact resistivity and the high microstructural defects which act as nonradiative recombination centers at the gain region. The effort to overcome these basic problems has not been successful. A fundamental reason for why these problems exist is that these class of materials being used are simply too soft to tolerate lattice stresses produced by mismatching. Material strength is determined by its intrinsic chemical nature (the bonding strength) and is not changeable.
Another approach to achieve the same blue and green LED and LD emissions is to use the direct bandgap (2.8 eV) of SiC (6H). Indeed, blue LED based on SiC has been produced commercially but the efficiency is very poor due to the high microstructure defects of the SiC devices. In this case, the material is much stronger than ZnSe so that even with such a high density of defects, the device still works. To improve efficiency, the system requires high quality defect-free SiC single crystals to make the substrates. Unfortunately, SiC single crystal can only be grown at extremely high temperatures (>2300.degree. C.) through a vapor transport process in order to achieve reasonable growth rates. This is an extremely difficult process. Current SiC substrates contain undesirable pipe-shaped voids. To improve the current bulk SiC growth technology to produce defect-free single crystal substrates is both difficult and costly. Thus, it is unlikely that SiC LED can be improved with the existing technology to produce efficient blue/green emissions.
A third approach to achieve the same blue and green LED and LD emissions is to use the direct energy wide-bandgap III-V nitride compound semiconductor materials such as AlN, GaN and InN. Again, producing blue and green emissions is difficult. In addition to the difficulty of producing the p-type doping layers, these compounds have another unique problem which does occur in other compound semiconductors. This additional problem is the lack of suitable substrate materials to grow high quality single crystal epitaxial thin films. Nevertheless, in December 1993, Nichia Chemical Co. of Japan has successfully developed a high brightness (100 times that of SiC LED) and high efficiency (3.8%) 450 nm blue LED based on a GaInN composition. However, Nichia's effort has the best performance but it is by no means the first disclosure on GaInN LEDs. There are many prior disclosures on the fabrication of GaInN LED such as U.S. Pat. No. 5,006,908 was issued to Nippon Telegraph and Telephone Co. (NTT) of Japan. In both Nichia and NTT cases, single crystal sapphire (Al.sub.2 O.sub.3) substrates were used to grow the GaN LED thin films because no better substrate materials are available. Since the lattice match between the sapphire substrate and the deposited GaInN film is very poor, the defect concentration is very high (on the order of 10.sup.9 -10.sup.11 dislocations per cm.sup.2). Nevertheless, since GaN is another physically strong material, similar to SiC, even with such a high defect density, the efficiency of these LED devices is still very high. Nichia's result showed that the GaN based compound semiconductor devices are the ideal candidates for LD applications. In late 1994, Cree Research Corporation of North Carolina has successfully fabricated high brightness blue LED based on GaN heterostructure films grown on SiC substrate. Despite the success of these blue LEDs, no one is able to produce any blue LDs based on these III-V nitride compound semiconductor materials.
The primary reason of failing to produce the blue GaN LDs is not because of the film deposition processes nor the impurity doping techniques. It is due to the lack of lattice matching substrates so that high quality GaN single crystal epitaxial films can not be produced. Since there is no lattice match between the GaN and the sapphire substrate, the active film is deposited over a buffer layer which is essentially fine polycrystalline mass. The overgrown active GaN layer can be highly oriented due to the preferential fast growth of those grains with [0001] orientation perpendicular to the surface. The large scattering loss at these grain boundaries is very difficult to overcome by the optical gain to achieve lasing.
III-V nitride compounds having the wurtzite structure which is hexagonal in symmetry, in general, have much smaller lattice constants (a-axis dimension=3.104.ANG. for AlN, 3.180.ANG. for GaN and 3.533 for InN) as compared to all the currently available semiconductor substrates which are all in cubic symmetry. See FIG. 1. Two of the most commonly known wurtzite structure compounds are SiC and ZnO. Both have lattice constants comparatively close to that of the III-V nitrides and both of them are considered and have been used as substrates for the epitaxial growth of nitride thin films. As previously mentioned, the Cree Corporation of North Carolina has succeeded to make a GaN blue LEDs on SiC substrate. However, both SiC and ZnO compounds have serious drawbacks and are not really suitable for this application.
SiC has an a-axis dimension of 3.076.ANG. (Table 2) which is 0.72% smaller than AlN and 3.09% smaller than GaN. To achieve good quality epitaxial thin film growth, it is necessary to have the substrate lattice matched as closely as possible, preferably better than 0.01% and in some cases 0.1%. Clearly, SiC's match is not good for AlN and much worse for GaN. Since AlN already has the smallest lattice constant among the III-V nitride compounds, there is no chance for SiC to get an exact match to any nitride composition. This is one of the reasons why only LED and not LD has been produced with SiC substrate.
In addition to the poor lattice matching, SiC has three additional problems: growth, defects and fabrication. SiC single crystal is produced by physical vapor deposition method at very high temperatures (>2300.degree. C.). The equipment is expensive and the growth process is slow. Moreover, current technology is limited to 30 mm in diameter and the maximum boule length is approximately 50 mm. Secondly, since the growth is invisible, it is not easy to control the growth process and the crystal defects can be very high, including inclusions and hallowed pipe defects. At present, there is no good solution to improve the growth and to eliminate these defects. Thirdly, SiC is a very hard material approaching to the hardness of diamond and it has been used extensively as abrasives. Therefore, wafer slicing and subsequent polishing are very slow processes. In addition, the combination of these problems further adds to the cost of these substrates. Based on these reasons, SiC is not a good substrate for III-V nitride compound semiconductor thin film growth.
Unlike SiC, the ZnO has a totally different set of problems. First, the a-axis lattice constant of 3.2496.ANG. is 4.69% bigger than that of AlN and 2.19% bigger than that of GaN (Table 2). ZnO will not match any of the (Al,Ga)N thin film compositions. But, ZnO does match to the Ga.sub.0.8 In.sub.0.2 N film composition. However, there are serious problems associated with the use of ZnO substrate. The first one is :growth. Even though ZnO has a melting temperature of 1975.degree. C., it can not be grown by the standard Czochralski pulling technique due to the high vapor pressure. Single crystals of ZnO have been produced by physical vapor transport, chemical vapor transport, flux growth and hydrothermal growth. Among them only physical vapor transport and hydrothermal methods have produced crystals greater than 1 cm in dimension. Thus far, the growth rate of all these methods are slow and the crystal size is also small. The crystal can easily develop a twin structure which is also a problem. The second problem is the chemical stability. ZnO crystal sublimes at very low temperatures (<1000.degree. C.) and also reacts with hydrogen at similar temperature range. Hydrogen is a common carrier for the metal organics chemical vapor deposition (MOCVD) process. As a consequence, a ZnO substrate will self-disintegrate at the GaN film deposition temperature. This is pan of the reason why no GaN LED has yet been made successfully on ZnO substrate.
The following is a summary of the state of the art of the blue/green LED and LD technologies and their problems:
(1) Both blue and green LEDs and LDs have been produced based on II-VI ZnSe compound semiconductors. Since these materials are softer than the carbides and nitrites, they suffer rapid device degradation with usage. The materials works well at cryogenic but not room temperatures.
(2) SiC LEDs have been produced commercially but they are not efficient due to high detect density. No LD has yet been produced based on SiC.
(3) High brightness blue LEDs are now produced commercially based on III-V nitride compound semiconductor materials. The nitride thin films are grown on sapphire (Al.sub.2 O.sub.3) substrates and are not true epitaxial films. Nevertheless, long term room temperature operation has been demonstrated. Because of poor lattice match, no LD has yet been produced. Blue III-V nitride LEDs are also produced using SiC substrate, again no LD has yet been produced. No nitride LED nor LD has successfully been made on ZnO substrates.

Modified wurtzite structure oxide compounds as substrates for III-V nitride compound semiconductor epitaxial thin film growth


An optical apparatus includes a rectangular optical member provided on an optical axis, a supporting member configured to support the optical member, and a rectangular vibrating device stuck to the optical member close to and in parallel with one of four sides of the optical member and configured to vibrate the optical member in a wave fashion to have a plurality of nodes parallel with the one side. The vibrating device is configured to operate in two or more vibration modes differing from one another at least in number or positions of the plurality of nodes. A support position at which the optical member is supported by the supporting member is a position of a portion of the optical member that corresponds to a node in a vibration mode other than a vibration mode whose amplitude is largest among the two or more vibration modes.

1. Field of the Invention
The present invention relates to a technology for removing a foreign substance, such as dust, adhering to a surface of an optical member provided on an optical axis of an optical apparatus, such as an imaging apparatus.
2. Description of the Related Art
In imaging apparatuses, such as digital cameras, which perform imaging of a subject by converting a subject image into an electrical signal, an imaging light-beam is received by an image sensor. Then, a photoelectric conversion signal output from the image sensor is converted into image data. The image data is recorded on a recording medium, such as a memory card. A charge-coupled device (CCD) or a complementary metal-oxide semiconductor (CMOS) sensor can be used as the image sensor.
In such imaging apparatuses, an optical low-pass filter or an infrared cut filter is disposed on a subject side of the image sensor. When foreign substances, such as dust, adhere to the surfaces of the filter, the foreign substances produce black spots in a captured image. Consequently, visual quality of the image deteriorates.
In particular, in digital single-lens reflex cameras with interchangeable lenses, mechanical operating units, such as a shutter and a quick-return mirror, are disposed in the vicinity of an image sensor. Sometimes, foreign substances, such as dust, are generated by the operating units and adhere to the surface of the image sensor or the filter. In addition, when the lens is changed, a foreign substance, such as dust, may enter the camera body from an opening of a lens mount and may adhere to the surface of the image sensor or the filter.
In order to avoid such phenomena, U.S. Patent Application Publication No. 2004/0169761 A discusses a technology for providing a dust-proof film, which transmits an imaging light-beam, on an object side of an image sensor, and for vibrating the dust-proof film using a piezoelectric element to remove a foreign substance, such as dust, adhering to the surface of the dust-proof film.
More specifically, U.S. Patent Application Publication No. 2004/0169761 A discusses a camera in which a dust-proof optical member is disposed between an image sensor and a mechanical shutter and below a finder optical system. In addition, a vibrating member for vibrating a peripheral edge portion of the optical member is provided in the camera and causes the optical member to perform resonant vibrations while switching between first-order and second-order vibration modes each having point-symmetric nodes. Consequently, dust adhering to the surface of the optical member can be removed.
In the camera discussed in U.S. Patent Application Publication No. 2004/0169761 A, when the optical member is caused to perform resonant vibrations, a supporting member is made to contact a portion corresponding to a node generated in the vicinity of a vibrating end of the optical member, at which a vibrating member is provided. However, in the case of using a plurality of vibration modes, it is unclear what vibration mode includes a node corresponding to the portion which the supporting member is made to contact. Considering a configuration in which the vibrating member is provided at one of opposite sides of the rectangular optical member, the optical member has a vibrating end (side at which the vibrating member is provided) and a free end (side at which the vibrating member is not provided) opposite the vibrating end. Generally, in a case where the supporting member is made to contact a portion other than those corresponding to nodes of a vibration, the vibration is attenuated. However, a degree of attenuation of the vibration in the vicinity of the free end is significantly high, as compared with that of attenuation of the vibration in the vicinity of the vibrating end. When the vibration of the optical member is largely attenuated, it is difficult to remove dust adhering to the surface of the optical member. Therefore, when the supporting member is made to contact a portion corresponding to a node of the vibration in the vicinity of the free end in the configuration in which the vibrating member is provided at one of opposite sides of the rectangular optical member, it is very important what vibration mode is selected in which a node corresponding to a portion contacting the supporting member is generated in the case of using a plurality of vibration modes.
In addition, when the supporting member is made to contact a portion corresponding to a node in a certain vibration mode in the case of using a plurality of vibration modes, an amplitude in that vibration mode may be too large. Accordingly, there is a fear of breakage of the optical member.

Optical apparatus having device for removing foreign substance


In order to provide a fuel cell powered vehicle testing system capable of performing a test of a power system of a fuel cell powered vehicle by a simpler facility, includes: a dynamometer which is connected to an output shaft of an electric motor mounted on a fuel cell powered vehicle for applying a simulation travelling load to the electric motor; and a supply power simulator adapted to simulate an operation of the fuel cell mounted on the fuel cell powered vehicle and to apply power to the electric motor, the power being to be supplied from the fuel cell to the electric motor.

Conventionally, as disclosed in, e.g., Patent Literature 1, there has been known a system for testing a power system in a single unit in order to identify performance of the power system before installation in a fuel cell powered vehicle and evaluate the power system in a process of development. In this Patent Literature 1, disclosed is a configuration of performing an evaluation test of the power system while the power system of the fuel cell powered vehicle is connected to a dynamo (here, noting that the power system includes an electric motor and a control device thereof). In this configuration, an actual fuel cell and auxiliary battery are connected to the electric motor in order to supply power and store regenerative power.
However, in this conventional system mentioned above, since the actual fuel cell is used, it is necessary to provide a high-pressure hydrogen tank or the like and there arises a problem of safety and the like relating to handling thereof. Therefore, surrounding facilities become large-scaled and it takes a great deal of time and effort to set-up for securing the safety.
Further, since a status of a fuel cell is changed by being affected by temperature, humidity, hydrogen pressure and the like, it is difficult to perform a repetitive test under the same condition and it is likely not to be able to achieve development and specify a defect smoothly.

Fuel cell powered vehicle testing system and method thereof


A filter construction particularly for vehicles and other spaces closed to the outside comprises a housing which has a filter compartment for containing the filter element with an opening to the compartment. A cover closes the opening and a locking mechanism for locking the cover in the closed position includes a slot defined in a frame portion of the housing and a lever member which is pivoted on the cover. The lever member has one arm portion with a nose which engages into the slot in the locked position and an opposite arm portion which carries a part of a bayonet joint which aligns with a complimentary part on the cover to fix the lever in the locked position. When the bayonet joint is released, the lever may be pivoted on the cover. The lever member has one arm portion with a nose which engages into the slot in the locked position and an opposite arm portion which carries a part of a bayonet joint which aligns with a complimentary part on the cover to fix the lever in the locked position. When the bayonet joint is released, the lever may be pivoted so that the nose moves out of the slot and releases the cover.

This invention relates in general to filter constructions and in particular to a new and useful filter and housing particularly for vehicle compartments and other spaces which are closed to the outside.
The room in the inside of vehicles for handling the exchange of used filter elements is very limited. This is particularly true for the opening of the filter housing in order to make the filter elements accessible.
Normally, the openings of filter housings are closed with covers, which are then opened and removed. Suitable constructions can be found for the covers and their gastight closures.
A known filter for cleaning air for rooms closed to the outside in its housing comprises several openings tightly sealed by covers for removal of filter units. Each cover is movably attached to the housing via two straps which are hinged both at the cover and at the housing. A closing rod, with a longitudinal slot which is tiltable and slidable is located between the straps in their support at the housing. The free end of the closing rod engages in its closing position with an ear attached to the housing. The closing rod carries a pressing screw for pressing the cover.
For opening, after release of the pressing screw, the closing rod is slid out of the ear and together with the straps the cover is turned up. The closure occurs in the opposite sequence. There are difficulties in applying this to limited space because of the sideway protrusion of the closure mechanism. Cover and closure remain with the housing and limit the accessibility during the change of the filter units. An immediate removal of loaded filter units into a protective bag is not possible. (German Pat. No. 12 81 267).
A known rapid closure for a releasable connection of a removable housing part, especially of a maintenance cover, with a stationary housing part comprises at least a gripping lever tiltably supported at one of the housing parts and one spring element prestressed by the lever and engaging the other housing part. This spring element is a leaf spring in the form of a rectangularly warped, two armed spiral spring. One arm is hung from its side on the stationary housing part toward the outside protruding, support strap, such that the end of the arm rests on the edge of the removable housing part and can press against it. The other arm which extends from the housing surface toward the outside has a connecting strap, which is hinged at the gripping lever and supported at the removable housing part. A disadvantage is that an open-position freely movable linked connection of gripping lever, connecting strap and spiral spring; the proper positioning and pressing of the closure requires both attention and the use of both hands. Operation in limited space is very difficult. For the hanging and disengaging of the spiral spring is necessary a larger free space on the side, which does not allow the arrangement of several covers in close spacing. (German Patent Application Disclosure DE-OS No. 25 34 612).


The invention provides an establishment of a secret session key shared Between two network elements (NEa, NEb) belonging to different network domains (NDa, NDb). A first network element (NEa) of a first network domain (NDa) requests security parameters from an associated key management center (KMC) (AAAa). Upon reception of the request, the KMC (AAAa) generates a freshness token (FRESH) and calculates the session key (K) based on this token (FRESH) and a master key (KAB) shared with a second network domain (NDb). The security parameters are (securely) provided to the network element (NEa), which extracts the session key (K) and forwards the freshness token (FRESH) to the KMC (AAAb) of the second domain (NDb) through a second network element (NEb). Based on the token (FRESH) and the shared master key (KAB), the KMC (AAAb) generates a copy of the session key (K), which is (securely) provided to the second network element (NEb). The two network elements (NEa, NEb) now have shares the session key (K), enabling them to securely communicate with each other.

A communications environment or system can generally be envisaged as comprising a plurality of independent communication network domains. Each such network domain can provide access to its services for users connected thereto. In order to provide mobility within the communications environment and across different domains it is typically desirable to establish communications, in particular secure communications, between network elements (NEs) belonging to the different domains. A typical example of such a secure inter-domain communication between two network elements is a secure communication tunnel between Security Gateways (SEGs) of two telecommunication or network operators.
In order to provide secure communication between network elements of different networks domains, a key management/key exchange protocol is typically used to establish the security parameters necessary for the inter-NE communication. There exist different types of key management protocols in the prior art, and they can generally be divided into two classes: symmetric key and public key protocols, respectively. The former relies, in principle, on a secret key that is shared between the parties and cryptographic techniques based on such key(s). The latter makes use of a pair of keys per party (a secret key and a public key), a trusted third party "validating" public keys and public key cryptography techniques.
In a feasibility study to support Network Domain Security (NDS)/Internet Protocol (IP) evolution for 3G mobile network operators [1] a fully meshed symmetric solution for secure inter-SEG communication is disclosed. In the disclosure of [1] each SEG shares a long-term secret key with each exterior SEG, i.e. each SEG belonging to another network domain, it wishes to (securely) communicate with. If each domain has access to one SEG and n is the total number of SEGs in the communications environment housing the domains, the number of long-term keys to be distributed to the SEGs and stored in each SEG will amount to
  n              n      -      1        2  if every SEG is to be able to communicate securely with every other SEG. Thus, the number of pre-shared secret keys can be very large and grows rapidly (with n2) in dependence of the number of active SEGs in the network domains. In addition, it is expected that each network domain can have more than one communicating NE or SEG, and that the SEGs/NEs need to communicate with a relatively large number of other SEGs/NEs in other network domains. Also adding a new SEG to an existing network domain requires large workload in the form of key distribution, management and storage. In addition, if a single SEG is broken or hacked, all SEGs in the different network domains have to be updated and new long-term secret keys have to be distributed therebetween.
Another possible solution, briefly mentioned in [1], is to employ a trusted third party, typically called Key Distribution Center (KDC), common to all network domains that is to communicate securely. In such a case, the KDC shares a secret key with each network domain it has a service agreement with. In order to establish secure communication between two NEs or SEGs of different network domains, the KDC distributes a fresh secret (usually not the same as the shared secret) to the parties that need to communicate. Typical examples in prior art of this solution are the Kerberos-based key management protocols. However, a drawback is that it is typically hard to find a suitable trusted third party that can act as a KDC, in particular in the case of inter-operator communication. In addition, increased administrative work is required to arrange for a common trust of this trusted third party solution. The KDC is also a possible single point of failure, if it is compromised, all network domains using its services are threatened.
The preferred key agreement protocol according to [1], which is also discussed in [2], is to utilize a Public Key Infrastructure (PKI) based method, whereby the SEGs or NEs share their public keys. The document [1] discloses a certificate-based solution without a Bridge Certification Authority (CA) PKI, or with a Bridge CA PKI, which is also further discussed in [2]. In either solution, each operator, whose NEs or SEGs are to communicate, has to sign the other party's root certificate. These certificates are then securely configured in each communicating SEG.
A major drawback with PKI protocols is that the (initial) cost of establishing a PKI infrastructure is very large. Furthermore, revocations of certificates require manual administration and revocation checks must always be performed (a certificate is a credential that is valid unless a verification returns that it is revoked), which requires on-line communication between the operators' Certificate Revocation Lists (CRLs). Moreover, the cryptographic operations involved in PKI solutions are expensive.


A system in a moving surveillance vehicle operates in background mode to capture images of license plates of neighboring moving vehicles, which may occupy lanes other than the lane in which the surveillance vehicle is moving. The images are used to determine the license plate numbers of the moving vehicles, which are then checked against a database to determine whether there are any potential law enforcement-related problems that require the attention of the operator. If so, the system alerts the operator using an audible tone, visual prompt, vibration, or in some other suitable manner. The entire process, including generation of the alert can occur autonomously of the operator.

Traffic police, highway patrol and other mobile security personnel have a need to accurately and efficiently identify potential law enforcement problems with respect to nearby motor vehicles. One well-recognized strategy is to "run" license plate numbers of such vehicles against a database.
It is a well known practice for an officer in a patrol car to visually read a license plate of a target vehicle, and then call in the number to a support center. It is also known for an officer to utilize an on-board digital video camera to capture an image of the vehicle license plate of a parked vehicle, and even to use an on-board computer to analyze the image to determine the license plate number. In both cases, however, conscious effort is required on the part of the officer, which diverts attention from driving or other activities. In some cases the diversion of attention can be dangerous, and can even contribute to an otherwise preventable car accident.
A highly advanced license plate recognition and checking system is described in Japanese patent 11-296785, published on Oct. 29, 1999, the disclosure of which is incorporated herein in its entirety by reference. In that system the patrol car is provided with an on-board camera and camera controller, optical character recognition (OCR) software, a database, and a display device. While moving along a road, the driver places the patrol car in front of or behind the target car, and then triggers operation of the camera. The camera photographs the license plate of a preceding or following target vehicle, and sends the captured image to the on-board computer. OCR software running on the computer determines the license plate number, and applies that number against the on-board database. The results are displayed to the operator.
Apparently, the inventors of Japanese patent 11-296785 did not appreciate that (a) forcing the driver of the patrol car to maneuver his vehicle relative to the target vehicle, and (b) forcing the operator to trigger the camera, involve conscious efforts on the part of the driver, which preclude the system from operating in a truly autonomous fashion. The issue of being fully autonomous is not a mere design choice. Fully autonomous operation is not only safer and more thorough, it also has a particularly important function in countering accusations of racial profiling. If a system could be devised that would autonomously process license plate information of all vehicles in view of the camera, including vehicles in other lanes, then the operator could not be reasonably accused of focusing on any particular car or driver.
Thus, there is still a need for more fully autonomous surveillance of moving automotive vehicles from another moving vehicle.

This patent is subject to a terminal disclaimer.

Autonomous wide-angle license plate recognition


A resin laminate containing: a layer (Layer A) of a modified ethylene/vinyl acetate copolymer resin obtained by the graft copolymerization of a vinyl acetate monomer onto an ethylene/vinyl acetate copolymer having a vinyl acetate content of 5-50% by weight, the modified ethylene/vinyl acetate copolymer resin having an MFR of 0.5 to 30 g/10 min. and a total vinyl acetate content of 20-80% by weight; and a layer (Layer B) of at least one thermoplastic resin selected from a styrene resin, an acrylic resin, a chlorine-containing resin, a polycarbonate resin and a thermoplastic polyester resin.

1. Field of the Invention
This invention relates to a resin laminate comprising a layer of a specific modified ethylene/vinyl acetate copolymer resin and a layer of a selected specific thermoplastic resin.
2. Background Art
Having the properties of being stable to heat, excelling in moldability and processability and being of low hygroscopicity, tasteless/odorless and chemically inert, styrene resins have so far been widely used for food containers, packaging materials, goods such as toys and writing utensils, parts of cars or electric appliances for home service, etc.
However, they have the disadvantages of being likely to be attacked by organic solvents, fragile and of insufficient heat resistance. For use as food containers in particular, resins having improved oil resistance, heat resistance and heat sealability are thus in great demand. In order to meet such demand, it has been attempted to laminate polyolefins such as polyethylene and polypropylene or other materials on styrene resins.
However, adhesives capable of making an effective bonding of such styrene resins to polyolefins or other materials are still unavailable. Referring to laminates of styrene resins with ethylene/vinyl acetate copolymer resins, by way of example, it has been attempted to introduce into them a larger amount of vinyl acetate in the form of a copolymer with ethylene in expectation of improvements in their adhesion. An increase in the vinyl acetate unit content of said copolymer, however, rather incurs a drop of its mechanical strength, thus failing to achieve a sufficient improvement in adhesion strength.
Laminates of styrene resins with polyolefins modified by grafting .alpha.,.beta.-unsaturated carboxylic acids onto them or containing epoxy groups, ordinarily known as adhesive polyolefins, have also been available; however, they are found to be less than satisfactory in terms of adhesion performance.
Acrylic resins, on the other hand, excel in various properties such as transparency, weather resistance, chemical resistance and electrical insulating quality and are light in weight, tough and of good processability, and so have been widely used as various molding and coating materials.
However, such acrylic resins, esp. methacrylic resins have the disadvantages of being more likely to be injured and more combustible than a competitive inorganic glass. The acrylic resins are also required to have more enhanced heat resistance and impact resistance for use as molding materials.
As one means for meeting such demands, the lamination of acrylic resins with polyolefins such as polyethylene and polypropylene or with other materials is considered effective.
Various adhesive resins have been proposed to bond acrylic resins to other materials. By way of example, ethylene/vinyl acetate copolymer resins having a relatively high vinyl acetate content may be mentioned.
However, the adhesion between acrylic resins and the copolymer resins is still far from satisfactory. In expectation of improvements in such adhesion, the introduction of a larger amount of vinyl acetate in the form of a copolymer with ethylene has been attempted. However, it has been found that the copolymerization of too large an amount of vinyl acetate rather incurs a drop of the mechanical strength of the resulting copolymer, thus failing to achieve appreciable improvements in adhesion strength.
Furthermore, chlorine-containing resins such as vinyl and vinylidene chloride resins have been available.
Generally excelling in various properties such as resistance to solvents, water, acids and alkalis and flame retardancy, vinyl chloride resins have so far been used in wide applications inclusive of films, wire coatings, floor materials, pipings and sheetings. Generally excelling in moistureproofness and gas barrier properties, vinylidene resins have found wide applications in various packaging films and coating moistureproof materials.
However, both the resins are relatively prone to degrade by heat and light and are too hard, and so should be used in combination with suitable stabilizers or plasticizers. In particular, a soft vinyl chloride resin has the disadvantages of being poor in cold resistance, oil resistance and creep resistance due to the plasticizer content being as high as about 30-40%. To make up for such disadvantages, the lamination of these resins with polyolefins such as polyethylene and polypropylene or with other materials is considered effective.
Various adhesive resins have been proposed so as to bond vinyl chloride resins or vinylidene chloride resins to other materials. An ethylene/vinyl acetate copolymer resin having a relatively high vinyl acetate content is one example.
However, the adhesion of vinyl chloride resins or vinylidene chloride resins to such an ethylene/vinyl acetate copolymer resin is still less than satisfactory. In expectation of improvements in this adhesion, the introduction of a larger amount of vinyl acetate in the form of an .alpha.-copolymer with ethylene has been attempted. However, the copolymerization of too large an amount of vinyl acetate rather incurs a drop of the mechanical strength of the resulting copolymer, thus failing to achieve appreciable improvements in the adhesion strength.
Polycarbonate resins are superior in such properties as heat resistance and mechanical strength, but practically is less than satisfactory in terms of chemical resistance and oxygen barrier properties.
In order to eliminate the disadvantages of such resins while making the best use of their advantages, it has been attempted to laminate on them resins having complementary properties, e.g. a polyolefin excelling in chemical resistance or a saponified ethylene/vinyl acetate copolymer excelling in oxygen barrier properties.
In particular, intensive studies have been made in fields of co-extrusion molding and co-injection molding capable of producing laminated structures efficiently and subsequent stretching.
However, any bonding agent to provide an effective bonding of polycarbonate resins to polyolefins or other materials is not developed as yet. Referring to the lamination of polycarbonate resins and ethylene/vinyl acetate copolymers, by way of example, the introduction of a large amount of vinyl acetate in the form of a copolymer with ethylene in expectation of improvements in adhesion rather gives rise to a drop of the mechanical strength of the resulting copolymers, thus failing to achieve appreciable improvements in adhesion strength.
Furthermore, the capability of polyolefins modified by grafting .alpha.,.beta.-unsaturated carboxylic acids onto them or containing epoxy groups--usually known as adhesive polyolefins--to bond to polycarbonate resins is less than satisfactory.
Thermoplastic polyester resins are superior in such properties as heat resistance and mechanical strength, but practically are far from satisfactory in terms of heat sealability and gas permeability.
In order to eliminate the disadvantage of such resins while making the best use of their advantages, it has been attempted to laminate on them resins having complementary properties, e.g. a polyolefin excelling in heat sealability or a saponified ethylene/vinyl acetate copolymer excelling in gas permeability.
In particular, intensive studies have been made in fields of co-extrusion molding and co-injection molding capable of producing laminated structures efficiently and subsequent stretching.
However, any bonding agent to provide an effective bonding of thermoplastic polyesters to polyolefins or other materials is not developed as yet. Referring to the lamination of a polyester and an ethylene/vinyl acetate copolymer, by way of example, the introduction of a large amount of vinyl acetate in the form of a copolymer with ethylene in expectation of improvements in adhesion rather gives rise to a drop of the mechanical strength of the resulting copolymer, thus failing to achieve appreciable improvements in adhesion strength.
Furthermore, the capability of polyolefins modified by grafting .alpha.,.beta.-unsaturated carboxylic acids onto them or containing epoxy groups--usually known as adhesive polyolefins--to bond to thermoplastic polyester is less than satisfactory.

Mitsubishi Pretrochemical Company Limited


A backrest includes first and second side wings and connectors configured to connect the first and second side wings to the wheelchair frame. The first side wing comprises a plurality of transverse profiles extending towards the second side wing and the second side wing comprises a plurality of second transverse profiles extending towards the first side wing. At least one first transverse profile of the first side wing and at least one associated second transverse profile of the second side wing are at least partially mutually embraced in a slidable manner. The at least one first transverse profile and the at least one second transverse profile are dimensioned and configured so that the mutual slidably embracement of the at least one first transverse profile and the at least one second transverse profile is made on a range of distances enabling the width adjustment of the backrest.

There is an increasing need for variable adjustment possibilities in order to adapt the backrest configuration, in particular its width, to the individual requirements of a particular wheelchair user. The requirements can occur from the need of comfort of the user or from the need of accommodation of a variety of health issues and reasons for wheelchair use.
Document U.S. Pat. No. 2,534,009 describes a conventional adjustable backrest, which comprises a pair of spaced apart side bars, each side bar having a plurality of spaced transverse bars extending therefrom towards the opposite side bar. The transverse bars of the two side bars comprise each a circular through hole and a slot. Fasteners pass through corresponding hole and slot in order to fasten the transverse bars together, the holes and slots being positioned so that the lateral spacing of the side bars is adjustable. According to this embodiment, the width adjustment of the backrest depends on the lengths of the slots, nevertheless the side bars do not contribute itself to the width adjustment and therefore limit the width adjustment. Moreover, the transverse bars of each side bar are not linked together so that the reliability of the assembly depends essentially on the connection means between the side bars and their transverse bars.
Document U.S. Pat. No. 5,564,786 describes an adjustable seat frame. The frame comprises a pair of spaced apart side rail having a plurality of spaced parallel transverse beams extending therefrom towards the opposite rail and a central beam telescopingly engaged between corresponding beams on each rail. Here again, the side rails do not contribute to the width adjustment of the frame and the transverse beams are not linked together. Due to the connections between each central beam and its corresponding transverse beams, this embodiment need two times more fastening means than the embodiment described in U.S. Pat. No. 2,534,009.


An toner cartridge and bias contact which pertains to the recharging of the cartridge by the development of a new way of making this electrical connection between the developer roller and the printer contact, in a most unique and simple way. In the best embodiment, an annular contact rides in the bore of the developer roller, pushed up against a stop where the bore diameter decreases, and the annular contact is tightly placed to attain accuracy, solidity, maximum contact and position. Also, a spring type contact may be used to set the gap of the doctor blade, controlling the distance between the developer roller and doctor blade. Alternately, a similar contact is attached to the end-felt roller seals of the developer roller. Electrical resistance has been provided to vary this bias voltage when desired and may even be added to the contact in the form of a resistant coating. A static limiter device which is used in the developer section to control voltage particularly when the humidity is low to prevent streaking and thus increase the usable range of humidity of the imaging device. The static limiter is made of screen as well as foil with pointed teeth, either grounded or charged opposite the developer roller charge.

This invention relates to solving problems on developer rollers as used in Xerography and more specifically in the toner cartridge remanufacturing industry. This includes copiers, laser printers and facsimile machines.
CANON has designed an all-in-one cartridge as in U.S. Pat. No. 4,975,744, issued Dec. 4, 1990 and assigned to CANON. Several companies have used these cartridges in laser printers, copy machines and facsimile machines, each with the varying printer engines and a different nameplate. Originally, these cartridges were designed to be "disposable". However, after the first all-in-one toner cartridge was introduced, it did not take long before laser cartridge remanufacturers such as applicant began remanufacturing cartridges. These "disposable" cartridges were designed to function for only one cartridge cycle without remanufacturing. The remanufacturers had found certain components that needed replacement on a regular basis. In 1990, the first aftermarket photoreceptor drum became available for use in remanufacturing the all-in-one cartridge of the "SX" engine variety, the most popular printer cartridge from around 1987 through 1994 at the time of this writing. When the long-life photoreceptor drum became available, the entire remanufacturing industry turned around and gained great strength and began a huge growth surge that still continues. In October 1993, HEWLETT-PACKARD, the largest seller of this printer engine using the all-in-one cartridge, entered the cartridge remanufacturing industry with the "Optiva" cartridge, further increasing the size as well as credibility of this relatively new industry. However, this relatively new industry grew from the all-in-one cartridge shortly after its debut. Before the introduction of the long-life drum, sometimes called the "superdrum" or "duradrum", the SX cartridge would last for around three cartridge remanufacturing cycles at best, since the maximum useful life of the OEM drum was three cycles. However, the long-life drums got their names from the fact that they were designed to last for many remanufacturing cycles or recharges as they are sometimes called. Typically, the long life drum can last for ten or more such cycles, unlike the typical OEM (Original Equipment Manufacturer) drum. With the additional developments of drum coatings, originally designed for OEM drums, the long-life drum may last for many additional cycles. Some coatings, in theory, were designed to be dissolved and removed from over the drum surface every 1-3 cycles, so the drum life of the long-life drum almost seems limitless.
However, with photoreceptor drums lasting for many cycles, other components of the cartridge have a tendency to require greater durability, a better solution, or a greater life. Also, as the success of these cartridges has skyrocketed, the demand is for cartrides with longer cycles, so component improvements are significant. Therefore, avoiding natural problems with prevention means must also be implemented for cartridges of longer life both in longer cycle times and greater number of cycles. Developer rollers and related components are no exception. They do not last indefinitely although there are some things that may be done to increase the life expectancy.
First, the most often seen developer roller contact has been the OEM copper alloy helical spring to supply a bias voltage to the inside wall of the developer roller. Many developer rollers have a magnetic core. The rotating helical spring is in constant contact with a stationary stainless steel spring-loaded welded-washer subassembly, where the welded-washer is contiguous with the assembly where printer contact is made. As the developer roller rotates, the helical spring is always in contact with the stainless steel welded-washer subassembly. The welded-washer subassembly provides the helical spring with the bias voltage connection supplied by the printer's electronic circuitry which then supplies the bias voltage to the aluminum developer roller sleeve on the inner wall. However, on a random basis, more frequently than desired, this connection between the stainless steel washer and the helical spring loses its integrity. It wears. It loses its spring force. The spring may be bent back to its original "design" position, but, it is a fairly time consuming task to bend it back out and even more difficult to obtain the correct bend. The OEM helical spring connects to the inner wall of the developer roller aluminum sleeve by digging into the inner wall with 2-4 prongs that eventually loosen up and decrease the quality of the electrical connection. Both the spring and washer may obtain deposits of insulative toner, or oxidation from the spring copper of the helical spring. Even a speck of insulative debris is enough to ruin the integrity of this connection. Since it rotates, the connection must be thought of as a connection for 360 degrees of rotation. A little speck of discontinuity is all it takes to ruin what would have otherwise been a perfect image. Similarly, in a 360 degree rotation of the developer roller, a small amount of imperfection from out-of roundness may also cause a decrease in integrity of the connection between the helical spring and the welded-washer subassembly. With this system, there are many places where it can go wrong. For example, the location where the washer touches the source of the bias voltage. There is the connection where the helical spring rotates, touching the welded-washer subassembly. The helical spring is part of an assembly that fits inside the developer roller. The assembly "bites" into the inner wall (usually aluminum) of the developer roller. It may eventually lose good contact at that point. Typically, these developer roller contacts bite into the inner wall in two or three small places. It may lose its connection integrity from the spring losing its original resiliency. However, whatever the reason it loses its integrity, it does not function the same as brand new over many cycles. Furthermore, the replacement components are not available from the OEM manufacturer. Consequently, remanufacturers have had to come up with their own solutions to this problem. Many Americans livelihoods are at stake when you look at the size of the cartridge remanufacturing industry.
I introduced the first solution to the problem when I wrote an article over two years ago about using conductive grease in this assembly where the helical spring contacts the stainless steel washer (Recharger February 1992, pg 95, "Tech Talk and New Ideas"). Others soon copied this idea and used other conductive greases. In the Summer of 1993 the debate began about which conductive greases are appropriate. There are two schools of conductive greases, very generally. The first type function well in practice, but by themselves do not conduct current as measured with a voltmeter or ohmeter. However, although this produced "miracle" results with my customers, the effectiveness of the grease fell off near the end of the cartridge cycle when the grease was gone. Furthermore, to grease the helical spring area for every cartridge cycle is too labor intensive. After getting to the difficult to reach helical spring and stainless steel washer, reassembly of the developer roller is very time consuming. This was the first fix known for this problem. Among the symptoms of not fixing this problem are uneven darkness on the output page, uneven blacks, uneven gray shades, and unsolid blacks. By using the conductive grease, the problem goes away. However, it is cumbersome to apply. I have been searching for a better way.
The other conductive grease, used by some, is a black conductive grease. This grease, when measured with an ohmeter, has continuity at any distance. However, unlike the other described grease which wears away near the end of the cycle, the black grease cakes up or hardens before the end of the cartridge cycle. In conclusion, conductive greases were a good fix before other solutions came about.
Applicant has invented a conductive grease that is a combination of the two schools of thought. By mixing the conductive grease that measures no conductivity with conductive carbon black and/or graphite, a conductive grease has been developed that has properties of each type and is conductive when measured with an ohmeter. By using silicon grease, a nonconductive, insulating grease used in automotive and aircraft industry, used as an insulative material around battery terminals, ignition systems, and sparkplug connections, to prevent corrosion, a material is made by DOW CORNING Corporation that meets the MIL-S-8660 specification and is essentially a moisture barrier. Any such insulative silicone grease, like the kind you see in an automotive store may be used as the main ingredient. By mixing the insulative grease with either/or conductive carbon black and/or conductive graphite, a highly conductive yet moisture-free conductive grease was developed for use where electrical connections are made and particularly electrical connections where there is mechanical motion. The conductive grease maintains the conductivity throughout at the contact points and is particularly useful in the imaging industry for charge roller contacts, drum axle contacts, and particularly developer roller bias contacts, as they will be discussed throughout this application.
A second improvement involves a spring inside the developer roller. In this development remanufacturers began by removing the helical spring assembly from inside the developer roller. They snipped off the helical portion, two helical prongs, from the helical spring assembly, placed the modified helical assembly back in the developer roller tube (no longer helical), and placed a coil spring between the assembly and the stainless welded-washer subassembly. I used a steel piano wire coil-spring in this place. One company used a copper alloy coil spring. Another company replaced the spring assembly with a copper alloy assembly to receive the coil spring and added to it a copper alloy washer to replace the stainless steel washer which may be used as an addition to it and the coil spring. However, this product was practical for large customers for only one main reason. It was found that reliability was low until the user used the product for a while. Then cartridge technicians began using assembly jigs to accurately place either the original modified helical assembly or its replacement assembly into the developer roller. Since precision is important, some remanufacturers find this kind of product desirable and others find it too time consuming. Many do not have the patience to learn to use it correctly. Even so, coil springs lose resilience with wear-time and this product, even when properly installed, has a limited life.
Another product that has come on the market is a clip for providing the bias voltage directly from the doctor blade to the developer roller, similar to the spring. The clip, similarly helps the bias voltage stay in contact with the developer roller sleeve, but on the outside wall of the developer roller sleeve, but it cuts a groove in the outer wall. The bias voltage is important for transporting toner from the developer roller to the photoreceptor drum. It is transported by two main forces. First, the photoreceptor drum has a charge on it for white space and a lack of or lesser charge where there is black image space. In other words, the charged surface of the photoreceptor drum repels toner while the uncharged pixels, where charge was removed by laser light, attract toner from the surface of the developer roller. The developer roller is continually ready to move toner to and from the photoreceptor drum in this selective fashion. However, the developer roller has a bias voltage that essentially in simplification repels and attracts toner to and from the photoreceptor drum. It is this bias voltage that is at the very core of the main problems that are solved in this invention. In simple terms, the bias voltage has an AC and DC component. The AC component essentially charges typically at 1600V AC and 1800 HZ while the DC component charges typically at -500 volts DC. The AC component at 1800 HZ essentially causes toner to jump on and off the developer roller sleeve, thus supplying a cloud of toner to the photoreceptor.
It is the continuity of the bias voltage that is the heart of the described prior art as well as an embodiment of this invention. For example, the conductive grease helped prevent the bias voltage discontinuity. The coil spring and kits, as well as the clip, did the same. However, a simpler, more effective bias voltage connector is needed.
The concept of static elimination/limitation is a known concept in electrostatics. For example, any sharp pointed metallic object that is either grounded or oppositely charged than an existing electrostatic charge or source of such a charge will diminish that charge. A static limiter device, however, consists of a set of many such pointed grounded or oppositely charged points. Some use sharp pointed metal and others use a metal object with a set of several evenly spaced wires protruding. This type of a device has been used in the SX printer, for example, in prior art, for charging the paper negatively (rather than grounding) to prevent thin paper from wrapping around the negatively charged photoreceptor drum at the transfer station where a positively charged transfer corona assembly charges. This is located in the printer, not in the toner cartridge. A device is needed to control the static electricity in the toner cartridge assembly adjacent the developer roller and drum to maintain the quality of the image. This device would increase the integrity of the bias voltage for better contact and, therefore, better image consistency and quality while allowing the printers, copiers and facsimile machines to operate under conditions that in current state-of-the-art it could not. With such a device the machines would be able to operate in a wider humidity range, at high altitudes, in the dry seasons when outdoor weather is very cold (although the machine is indoors) and in dry desert climates.

Method and apparatus for electrically connecting a developer roller to a bias source


A probe submersible in a liquid to continuously analyze the concentration of a gas such as oxygen dissolved therein. The probe is constituted by a casing having an open mouth covered by a gas-permeable membrane to define a chamber filled with an electrolyte. Disposed within the chamber is a measuring electrode and a counter-electrode, the front face of the measuring electrode being slightly spaced from the rear surface of the membrane to create a gap that is filled by the electrolyte. Holes are formed in the measuring electrode to permit the passage of electrolyte between the front and rear faces thereof, the rear face being coated with an insulating layer to prevent an electrochemical reaction between this face and the electrolyte whereby the probe is then insensitive to dissolved gas contained in the electrolyte and responds only to gas contained in the liquid being analyzed. The walls of the holes may also be lined with an insulation layer for the same purpose.

This invention relates generally to a submersible probe adapted to continuously analyze the concentration of a gas such as oxygen dissolved in a liquid, and more particularly to a probe of this type having an improved measuring electrode structure.
In liquid wastes, the factor which determines whether biological changes are being brought about by aerobic or by anaerobic organisms is dissolved oxygen. Aerobic activity requires free oxygen and produces innocuous end products, whereas anaerobic activity can utilize chemically bonded oxygen such as sulfates to produce end products which are obnoxious. Because both types are ubiquitous in nature, it is vital in waste treatment that conditions conducive to aerobic activity be encouraged, for otherwise anaerobic organisms will take over.
Thus in aerobic treatment processes intended to purify sewage and industrial wastes, the present practice is to continuously measure the dissolved oxygen in order to monitor and maintain proper aerobic conditions. Since all aerobic treatment techniques depend upon the presence of dissolved oxygen, the continuous testing thereof is essential when regulating the rate of aeration not only to insure that the supply of oxygen is adequate to maintain aerobic conditions, but also to prevent excessive use of energy needed for aeration.
The need for dissolved oxygen measurement is by no means limited to sanitary engineering, for oxygen is a significant factor in iron and steel corrosion, such as in steam boilers. Thus in control systems for removing oxygen from boiler-feed waters, it is customary in the power industry to measure the dissolved oxygen concentration.
Dissolved oxygen probes of the electrochemical type are well known. Some of these probes exploit the magnitude of the depolarizing effect of oxygen on a special galvanic cell. Thus in U.S. Pat. Nos. 3,510,421 and 3,239,444 there are disclosed embodiments of electrochemical cells which are immersible in liquid for measuring the concentration of dissolved oxygen. In its simplest form, the cell is constituted by an anode or counter-electrode and a cathode or measuring electrode bridged by an electrolyte. The cell is adapted by means of a diffusion membrane covering the measuring electrode and permeable only to gases but impermeable to liquids to receive a sample of oxygen. Upon the entry of the sample, a chemical reaction occurs, modifying the electrical characteristics of the cell. Also of background interest is the 1976 patent to Poole, U.S. Pat. No. 3,948,746 and the prior art cited therein.