Patents by Inventor Yoshikuni Tohyama

Yoshikuni Tohyama has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4916490
    Abstract: An image forming apparatus including at least first and second developing devices for developing latent images formed on an image bearing member. The first and second developing devices contain developers of different colors, respectively. The second developing device contains a developer of a predetermined color and is fixedly mounted in the image forming apparatus. The first developing device contains a developer of a color other than the predetermined color and is detachably mountable in the image forming apparatus. Only the first developing device is exchangeable.
    Type: Grant
    Filed: January 9, 1989
    Date of Patent: April 10, 1990
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hidetoshi Tanaka, Yoshikuni Tohyama
  • Patent number: 4845528
    Abstract: A double-sided image forming apparatus having first and second input devices respectively for entering function data for desired image formation functions and for entering the number of copies to be formed. A memory is provided to store the function data, and a storage compartment is provided to store sheets during duplex copying. An image forming device is arranged to operate in two procedures: a first procedure in which image formation is effected on the sheet's first side in accordance with first function data, and a second procedure in which image formation is effected on the other side in accordance with a second, different, function data. A controller controls the image forming device so that entry of number data and function data is permitted before the first procedure begins, but so that entry of only function data and not number data is permitted after completion of the first procedure.
    Type: Grant
    Filed: December 16, 1987
    Date of Patent: July 4, 1989
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tomohiro Aoki, Kazuo Kawakubo, Katsushi Furuichi, Kiyokazu Namekata, Hidetoshi Tanaka, Yoshikuni Tohyama, Toshirou Kasamura, Toshio Honma
  • Patent number: 4803520
    Abstract: An electrophotographic apparatus capable of synthesizing two images with a cleaner boundary. Two images are synthesized by forming two images in respectively designated areas, and cleaner boundary is obtained by erasing any image in the boundary zone of these two images.
    Type: Grant
    Filed: October 31, 1985
    Date of Patent: February 7, 1989
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masahiro Tomosada, Hiroshi Ogawa, Yoshikuni Tohyama, Hideki Adachi, Tadashi Suzuki, Naoyuki Ohki
  • Patent number: 4544262
    Abstract: A transfer type image formation apparatus is of such a type that a transfer material is placed in close contact with an image bearing member in an image transfer station, and then separated from the image bearing member by separating means after the image on the image bearing member has been transferred onto the transfer material by transferring means, wherein a rotary member is located upstream of the separating means in the direction of movement of the transfer material, the rotary member being adapted to make a rolling contact with the image bearing member such that the image can stably be transferred onto the transfer material.
    Type: Grant
    Filed: July 11, 1983
    Date of Patent: October 1, 1985
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shinji Kanemitsu, Yoshikuni Tohyama
  • Patent number: 4402595
    Abstract: A scanning type image formation apparatus capable of selectively changing image magnifications is provided with a mirror for scanning an original, movable support means for supporting the mirror, a moving member to which a drive force transmitting member is connected and which is caused to move along a predetermined path for scanning of the original by the drive force transmitted by the drive force transmitting member, connecting means for connecting to the moving member the movable support means supporting the mirror, and means for changing the connected position of the movable support means to the moving member to change the length of the light path correspondingly to a selected magnification.
    Type: Grant
    Filed: March 18, 1981
    Date of Patent: September 6, 1983
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hiroshi Ogawa, Tateki Nagaoka, Yoshikuni Tohyama
  • Patent number: 4375331
    Abstract: In a slit exposure scanning type copying machine or the like, a thin white member is fixedly disposed in the image forming main optical path from the vicinity of the end of an original stopping reference member or the vicinity of the end of an original carriage keep member, whereby the image forming main light beam from said vicinity of the end is not effectively transmitted to an image plane but instead, part of an illuminating light beam for illuminating an original from the opposite sides thereof is reflected by the white member, thereby forming predetermined blank spaces at the end portions of copy paper corresponding to the scanning starting end and the scanning terminating end. The white member is disposed at a predetermined angle with respect to the original by taking the scanning direction into account so that the shadow thereof imparted to the slit exposure area on the original surface does not greatly decrease the quantity of light of the illuminating light beam which contributes to image formation.
    Type: Grant
    Filed: June 3, 1980
    Date of Patent: March 1, 1983
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yoshikuni Tohyama, Akihiko Katsura
  • Patent number: 4323308
    Abstract: A copy magnification modifying apparatus for changing the copy magnification by displacing optical members involved in the image formation to and maintaining the same at a position capable of forming an image of a selected magnification of an original onto a photosensitive member, including a rotary drive source, an optical member displacing mechanism for transmitting the drive force of the rotary drive source through one-directional rotary clutch and resilient member to said optical members thereby guiding the same along a determined path, an optical member stopper for stopping said optical members at a position corresponding to the selected image magnification, and a drive source control system adapted for continuing the function of the rotary drive source after the stopping of the optical members to cause a deformation in a resilient member thereby generating a resilient force biasing the one-directional rotary clutch in a direction opposite to the rotating direction thereof.
    Type: Grant
    Filed: December 31, 1980
    Date of Patent: April 6, 1982
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tadayuki Kitajima, Yoshikuni Tohyama
  • Patent number: 4302098
    Abstract: Apparatus for printing reproduction copies of an original image or recording such original image on an image recording member, is provided with a device for determining whether the image to be recorded conforms in size to the image recording member. The apparatus provides an indication to the operator of the apparatus when non-conformance is detected.
    Type: Grant
    Filed: November 13, 1979
    Date of Patent: November 24, 1981
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yasuhito Kan, Yoshimasa Kimura, Masato Ishida, Koichi Miyamoto, Yoshikuni Tohyama
  • Patent number: 4243311
    Abstract: A scanning apparatus includes a scanner, a driver for reciprocating the scanner, and a control mechanism which controls the drive force of said driver so as to drive the scanner with a low acceleration at the initial stage of drive of the scanner.
    Type: Grant
    Filed: August 29, 1978
    Date of Patent: January 6, 1981
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yoshikuni Tohyama, Yoshimasa Kimura, Masato Ishida, Koichi Miyamoto
  • Patent number: 4218131
    Abstract: A cleaning device for removing developer remaining on the surface of an image-bearing member comprises wiper means having a resilient blade member adapted to bear against the surface of the image-bearing member, guide means having a guide member defining, with the resilient blade member, a slit-like opening through which the removed substance from the image-bearing surface is introduced, conveyor means for conveying the collected substance along a conveyance path substantially parallel to the slit-like opening and axially of the image-bearing member, and seal means for sealing the space between the slit-like opening and the conveyance path.
    Type: Grant
    Filed: August 17, 1978
    Date of Patent: August 19, 1980
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yoshio Ito, Katuhiko Yamada, Tadayuki Kitajima, Koichi Miyamoto, Hiroo Kobayashi, Yoshikuni Tohyama
  • Patent number: 4168901
    Abstract: This specification discloses a developer treating device for preventing scattering or similar phenomenon of developer in an electrophotographic copying machine. The device is applicable to a developing device, a cleaning device or the like disposed in opposed relationship with the surface of a photosensitive medium to be developed or to be cleaned. In order that the flow of developer may be positively utilized to prevent the same from flowing out of the developing device or the cleaning device, the device has a developer scatter preventing member such as stay or the like which forms a multistage slit between itself and the surface of the photosensitive medium.
    Type: Grant
    Filed: August 5, 1977
    Date of Patent: September 25, 1979
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yoshio Ito, Katuhiko Yamada, Tadayuki Kitajima, Koichi Miyamoto, Hiroo Kobayashi, Yoshikuni Tohyama
  • Patent number: 4163549
    Abstract: This specification discloses improvements in a separating belt disposed between an image-bearing member such as a photosensitive medium or the like and a transfer medium to which the image on the image-bearing member is to be transferred. In the device of the prior art, the separating belt has been fatigued by being subjected to localized friction with respect to the image-bearing member and/or a rotating member for effecting the separation. In the present invention, the separating belt is gradually moved in accordance with the operation of the device incorporating the separating belt therein, whereby the separating belt may be prevented from localized friction and need not be replaced by another belt for a long time.
    Type: Grant
    Filed: March 15, 1977
    Date of Patent: August 7, 1979
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yoshio Ito, Yoshikuni Tohyama, Seiji Sagara
  • Patent number: 4129377
    Abstract: A variable magnification copying apparatus includes optical scanning means for scanning an image original at a variable velocity in accordance with a copying magnification desired, a photosensitive drum movable at a predetermined velocity from an exposure station to an image transfer station, conveyor means for conveying copy medium to the image transfer station, detector means for generating a signal when the scanning means has scanned an edge of the image original or a portion thereof near the edge, and control means coupled to the detector means for controlling the conveyor means by the signal so as to ensure the image of the original to be copied with the leading edge thereof registered to the leading edge of the copy medium with respect to the direction of conveyance, irrespective of changes in magnification.
    Type: Grant
    Filed: December 14, 1976
    Date of Patent: December 12, 1978
    Assignee: Canon Kabushiki Kaisha
    Inventors: Koichi Miyamoto, Yoshikuni Tohyama, Seiji Sagara, Yoshimasa Kimura, Masato Ishida
  • Patent number: 4072211
    Abstract: A driving device for a moving body comprises a drive shaft normally rotated in one direction by a drive source, a follower shaft in engagement with the drive shaft to transmit the drive to the moving body, one-way connecting means loosely mounted on the drive shaft to connect and disconnect the drive of the drive shaft to the follower shaft, and accumulator means for accumulating the returning force of the moving body by utilizing the movement of the moving body resulting from the normal rotation of the follower shaft. The follower shaft may be reversed in rotation by the accumulator means upon disconnection of the one-way connecting means and the speed of the reverse rotation of the follower shaft is controlled by operation of the one-way connecting means so as not to exceed the driving speed of the drive shaft.
    Type: Grant
    Filed: June 17, 1976
    Date of Patent: February 7, 1978
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tadayuki Kitajima, Yoshikuni Tohyama
  • Patent number: 4000942
    Abstract: In an electrophotographic copying apparatus of the type in which a toner image is transferred from the surface of a photosensitive medium to a transfer medium, a transfer medium separating device comprises a rotatable separating roller disposed downstream of an image transfer station where a toner image is transferred from the surface of the photosensitive medium to the transfer medium, a transfer medium end guide belt disposed in contact with the peripheral surface of the rotatable separating roller for separating one end of the transfer medium from the surface of the photosensitive medium at the image transfer station and for guiding the transfer medium away from the photosensitive medium after the image transfer, and a rotatable pressure roller disposed in pressure contact with the rotatable separating roller for transporting the transfer medium while urging the same against the rotatable separating roller and for separating the transfer medium from the surface of the photosensitive medium.
    Type: Grant
    Filed: December 23, 1975
    Date of Patent: January 4, 1977
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yoshio Ito, Katuhiko Yamada, Tadayuki Kitajima, Koichi Miyamoto, Hiroo Kobayashi, Yoshikuni Tohyama