Patents Examined by T. A. Dang
  • Patent number: 5602712
    Abstract: An object, typically photoconductor drum is electrically charged by placing a contact charger member in abutment with the object to be charged and applying voltage between the contact charger member and the object. Charging is effected by properly controlling the capacitance of the contact charger member, the capacitance of the object, and the applied voltage. A sufficient charged potential is achieved through the application of a relatively low voltage, while preventing ozone generation.
    Type: Grant
    Filed: September 25, 1992
    Date of Patent: February 11, 1997
    Assignee: Bridgestone Corporation
    Inventors: Hideharu Daifuku, Yoshitomo Masuda, Kinya Suzuki, Hiroshi Harashima, Hiroshi Kaneda, Yoshio Takizawa, Takahiro Kawagoe
  • Patent number: 5581334
    Abstract: In an electrostatic image developing device for electrical photocopiers, a magnetizable one-component toner, initially contained in a removable container, is fed, by the action of a rotating flexible strip, through a development chamber towards a rotating non-magnetic development roller surrounding a number of stationary permanent magnets, forming on it a magnetic brush, whose thickness is controlled by a non-magnetic flexible blade pressed against the surface of the development roller; the development chamber is fitted with three stirring bars made of non-magnetic material, each bar describing a different closed path in different zones of the development chamber in such a way as to avoid the formation of lumps and to maintain the correct fluidity of the toner. In addition, a metallic wire is fitted in the development chamber and acts as a sensor device to detect when the removable container is nearly empty of toner.
    Type: Grant
    Filed: January 19, 1995
    Date of Patent: December 3, 1996
    Assignee: Olivetti-Canon Industriale S.p.A.
    Inventors: Riccardo Forlani, Renato Bortolin, Riccardo Dal Bianco, Roberto Guelfo
  • Patent number: 5579101
    Abstract: A developer cartridge detachably mountable to a developing apparatus having a shutter for closing and opening a developer receiving opening, includes a cylindrical portion for accommodating a developer, the cylindrical portion being provided with an opening extending along a length thereof; a sealing member for sealing the opening; a first projection for moving the shutter to an open position for the developer receiving opening in interrelation with rotation of the developer cartridge in a first direction; and a second projection for moving the shutter to a close position for the developer receiving opening in interrelation with rotation of the developer cartridge in a second direction which is opposite from the first direction.
    Type: Grant
    Filed: December 28, 1994
    Date of Patent: November 26, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazuhiko Omata, Yutaka Ban, Akihito Kanamori, Kazuyuki Miyano
  • Patent number: 5555083
    Abstract: A decurler for reducing cross curl in sheets includes at least one grooved elastomer transport belt and a ribbed pinch shaft. The ribs of the decurler shaft extend into the grooves in the belt to provide one-sided corrugations to a passing sheet and provide distributed localized bending of the copy sheet in the area of the belt grooves. Distributed local bending in the cross direction, as well as, in the wrap in the process direction around the ribbed decurler shaft provide cross curl reduction in the process direction.
    Type: Grant
    Filed: October 3, 1994
    Date of Patent: September 10, 1996
    Assignee: Xerox Corporation
    Inventors: Youti Kuo, James F. Smoak
  • Patent number: 5517296
    Abstract: An image forming apparatus includes a plurality of image forming units having a photoconductive device for forming a latent image and a developing device for developing the latent image, an exposing device for exposing the photoconductive device, and a transfer device for transferring the image developed on the photoconductive device onto a sheet of paper. The apparatus is compact and performs a stable driving because the light and small exposing device and transfer device move with respect to the plurality of image forming units, thereby providing a good-quality image and facilitating the maintenance of the apparatus.
    Type: Grant
    Filed: October 7, 1994
    Date of Patent: May 14, 1996
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Min-ho Choi, Kyung-hwan Kim, Byeong-sik Cheon, Jin-geun Kwak
  • Patent number: 5500722
    Abstract: Release Agent Management system for a heat and pressure fuser for fixing black toner images in low and high volume imaging machines and also for fixing color images. An auxiliary oil supply is provided for applying extra oil to an oil impregnated web. The extra oil improves fuser roll release life in every application. Also, enables color fusing which requires higher oil application rates.
    Type: Grant
    Filed: August 3, 1992
    Date of Patent: March 19, 1996
    Assignee: Xerox Corporation
    Inventor: Robert M. Jacobs
  • Patent number: 5499093
    Abstract: An electrostatographic single-pass multiple station multi-color printer for forming an image onto a web has a plurality of toner image-printing electrostatographic stations. Each station has a drum onto the surface of which a toner image can be formed. An exposure station forms an electrostatic toner image line-wise on each drum surface. A corona device transfers the toner image onto the web, which is conveyed in succession past the stations in synchronism with the rotation of the drum surface. Register control apparatus provided for controlling the operation of each of the stations in timed relationship thereby to obtain correct registering of the distinct toner images on the web. The register control apparatus comprises an encoder driven by the displacement of the web to produce pulses indicative of web displacement, and a delay arranged to initiate the operation of subsequent stations after a predetermined web displacement, as measured by the encoder, has occurred.
    Type: Grant
    Filed: June 8, 1994
    Date of Patent: March 12, 1996
    Assignee: Xeikon NV
    Inventors: Ronny J. V. Aerens, Etienne M. De Cock, Lucien A. De Schamphelaere, Peter A. R. Steylaerts, Erik G. G. Van Weverberg
  • Patent number: 5497222
    Abstract: An imaging system including an image bearing surface and an intermediate transfer member operative for transfer of toner images from the image bearing surface to a transfer surface of the intermediate transfer member and for subsequent transfer to a substrate.The intermediate transfer member includes a compressible layer, a backing layer disposed away from said image bearing surface and a heating layer. The heating layer is disposed intermediate backing layer and said transfer surface.
    Type: Grant
    Filed: March 20, 1995
    Date of Patent: March 5, 1996
    Assignee: Indigo N.V.
    Inventors: Benzion Landa, Hanna Pinhas, Paul Fenster
  • Patent number: 5486902
    Abstract: The present invention relates to an apparatus for forming color toner images on an electrophotographic photosensitive member and for transferring the color toner images onto a transfer member, in which the vibration is prevented from acting on the photosensitive member during a latent image corresponding to each color image is formed, thereby improving the image quality. That is to say, when a peripheral length of the transfer member is L.sub.1, a distance between a light illuminating position of the light information illuminating means on the photosensitive member and a transfer position of the transfer member is L.sub.2, and a length of a maximum image formed on the transfer member is L.sub.3, a relation (L.sub.1 -L.sub.3)>L.sub.2 is established, thereby preventing the vibration from acting on the photosensitive member.
    Type: Grant
    Filed: February 23, 1994
    Date of Patent: January 23, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventor: Akira Ito
  • Patent number: 5479241
    Abstract: An electrophotographic printing machine is provided having an endless photoreceptor belt arranged to move in a predetermined path through a plurality of processing stations. The apparatus is used in conjunction with a method for automatically and repeatedly measuring and updating a steering coefficient used in an automatic steering mode. The method includes centering the belt and finding the average "in" belt walk and "in" belt walk rate and the average "out" belt walk and "out" belt walk rate, in order to determine the steering control coefficient. The method allows for a single machine to have its steering coefficient repeatedly updated.
    Type: Grant
    Filed: January 19, 1993
    Date of Patent: December 26, 1995
    Assignee: Xerox Corporation
    Inventors: Ssujan Hou, Jacob N. Kluger
  • Patent number: 5479243
    Abstract: An electrophotographic image forming apparatus using a charge roller for uniformly charging the surface of a photoconductive element, or image carrier, during image formation, and a charging device having the charge roller. The charging efficiency is enhanced, and a uniform charge distribution is set up by the application of a DC voltage only. This suppresses the increase in the cost of an apparatus, the increase in power source cost, and the generation of a great amount of ozone. As a result, a charging member and a photoconductive element are prevented from being deteriorated while environmental pollution is eliminated.
    Type: Grant
    Filed: March 21, 1994
    Date of Patent: December 26, 1995
    Assignee: Ricoh Company, Ltd.
    Inventors: Junji Kurokawa, Kazuo Nojima, Masako Chiba, Toshio Nakahara
  • Patent number: 5477308
    Abstract: An image forming apparatus is designed to compensate for voltage to be applied to an exposure lamp and a charger in accordance with changes in the density of a toner image formed on a photoreceptor that occur from its initial state to its final state after an image forming operation. More specifically, the density of a reference toner image is measured by a toner-density sensor. The amount of change in the density is measured beginning with its initial state by a subtracter, and the amount of compensation for the voltage required for obtaining the optimum image quality is found. By using these amounts of compensation as teaching data, learning is made as to the relationship between the amount of change in the density and the amount of compensation in a neurocomputer. Upon forming an image, the neurocomputer executes operations in accordance with the contents of the learning based on an inputted amount of change in density, and finds an appropriate amount of compensation.
    Type: Grant
    Filed: November 24, 1993
    Date of Patent: December 19, 1995
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Kazuyuki Ohnishi, Yasutaka Maeda, Yoichi Shimazawa, Mihoko Okada, Yuichi Kazaki, Shin-ichirou Ohhashi, Yoshie Iwakura
  • Patent number: 5475481
    Abstract: In an electrophotographic imaging apparatus, an imaging operation, to form an image on a continuous recording sheet, is executed. First, an unfixed toner image is transferred on the recording sheet, and fixed by a pair of fixing rollers, while the imaging operation is executed, the continuous sheet is fed. If all of the transferred images, i.e., unfixed images have been fixed, the fixing operation is stopped, and at least one of the fixing rollers is retracted.
    Type: Grant
    Filed: December 29, 1993
    Date of Patent: December 12, 1995
    Assignee: Asahi Kogaku Kogyo Kabushiki Kaisha
    Inventors: Tomoyuki Nishikawa, Yoshimi Saito
  • Patent number: 5473350
    Abstract: Ink concentration in a system is maintained regardless of the duty cycle under which the system is operating. In an ink jet system, a print head receives ink from the main ink supply and forms continuous drops. The drops needed for printing to form the desired image are selected from the continuously formed drops. Based on the selection, a count signal is produced indicative of the number of drops printed. An ink level sensor in the main ink reservoir generates a low ink level signal when ink in the reservoir reaches a predetermined low level, the difference between a normal level and the low level corresponding to a predetermined cycle volume. A fluid connection selectively allows flow into the main ink reservoir from either the external supply of ink or the external supply of ink replenisher.
    Type: Grant
    Filed: August 6, 1992
    Date of Patent: December 5, 1995
    Assignee: Scitex Digital Printing, Inc.
    Inventors: Rodney G. Mader, James C. Ralston
  • Patent number: 5471291
    Abstract: In imaging apparatus (1) a contact heater (9) applies heat and electrical bias to a toner image on an intermediate accumulator (5). The bias is of polarity to repel the toner. The toner image is coalesced such that additional heating may be reduced or eliminated at the transfer to paper (7) by pressure roller (11).
    Type: Grant
    Filed: May 31, 1994
    Date of Patent: November 28, 1995
    Assignee: Lexmark International, Inc.
    Inventors: Todd L. Janes, Alexander D. Meade, Ashok Murthy, Pramod K. Sharma, Peter E. Wallin
  • Patent number: 5469243
    Abstract: For an image forming apparatus having a photoreceptor whose surface is charged by a main charger unit, a function is provided that a desired electric potential is attained on the photoreceptor surface by applying a lowest main charging voltage to the charger unit. By providing a plurality of grid voltages, it is possible that there are a plurality of main charging voltages suitable for the desired surface potential, and the lowest main charging voltage and the corresponding grid voltage can be selected thereamong.
    Type: Grant
    Filed: March 16, 1994
    Date of Patent: November 21, 1995
    Assignee: Mita Industrial Co., Ltd.
    Inventors: Yasushi Saitoh, Masashi Matsumoto, Takao Ichihashi, Shuji Yamada
  • Patent number: 5467175
    Abstract: In a developing device for developing a latent image formed on an image carrier with a developer, a developer carrier conveys the developer deposited thereon to the image carrier. A developer driving section moves, in a position adjoining the developer carrier and where the developer is at least apt to aggregate, the developer such that the developer is loosened. A developer charging member deposits a predetermined amount of charge on the developer. The developer charging member is located downstream of the developer driving section with respect to the direction of rotation of the developer carrier and upstream of a developing position where the developer carrier faces the image carrier. The device is small size and inexpensive since it does not include a conventional sponge roller or similar developer supply member.
    Type: Grant
    Filed: December 27, 1993
    Date of Patent: November 14, 1995
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiromitsu Takagaki, Nobuo Iwata, Koji Suzuki
  • Patent number: 5459553
    Abstract: A method for eliminating a paper jam from an image forming system is disclosed. The image forming system includes: an engine driving motor, register rollers for arranging paper received from a paper cassette, a register roller clutch for enabling and disabling transmission of rotational power from the engine driving motor to the register rollers, and fixing rollers for securing toner onto a surface of the paper and then delivering the paper to an exterior of the system. The paper jam elimination method includes the steps of: determining whether a paper jam has occurred, displaying an indication of the paper jam upon its detection, determining whether a paper jam elimination mode is activated, engaging register roller clutch upon activation of the paper jam elimination mode, and then activating engine driving motor to thereby deliver jammed paper to an exterior of the image forming system.
    Type: Grant
    Filed: May 24, 1994
    Date of Patent: October 17, 1995
    Assignee: SamSung Electronics Co., Ltd.
    Inventor: Sung-Eun Kim
  • Patent number: 5459556
    Abstract: A toner meter for determining a rate of toner usage per print in a printing machine of the type having operator actuatable settings effecting the rate of toner usage per print. The meter has a controller for calculating the rate of toner usage per print responsive to actuation of an operator actuatable setting and a indicator in communication with the controller, for indicating the calculated rate of toner usage.
    Type: Grant
    Filed: January 12, 1994
    Date of Patent: October 17, 1995
    Assignee: Xerox Corporation
    Inventors: Thomas Acquaviva, Michael A. Garofalo
  • Patent number: RE35528
    Abstract: A xerographic image recording apparatus includes a photosensitive body moved along a circuitous path, an electric discharging unit for eliminating electric charges from the photosensitive body, a precharging unit for charging the photosensitive body electrically, an image writing unit for writing an image on the photosensitive body, an image developing unit for coating the photosensitive body by the toner to form a toner image on the photosensitive body; a recording sheet feeding unit for feeding a recording sheet along a sheet path, an image transfer unit for transferring the toner image onto a recording sheet, a cleaning unit for removing the toner remaining on the photosensitive body after the transfer of image on the recording sheet is completed, a toner supply tank for supplying the toner to the image developing unit, and a toner recovery tank for collecting the toner removed by the cleaning unit from the photosensitive body, wherein the toner supply tank and the toner recovery tank are assembled into a
    Type: Grant
    Filed: June 30, 1994
    Date of Patent: June 10, 1997
    Assignee: Ricoh Company, Ltd.
    Inventors: Yozo Matsuura, Shiroh Kondoh, Kazuhiro Yuasa, Hiroshi Saitoh, Hiroyuki Kiyoi, Masanori Yoshimura, Masahiro Kawabe, Yoshiya Itoh