Patents by Inventor Shuho Yokokawa

Shuho Yokokawa 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: 6130408
    Abstract: A heating belt is laid along a conveying path for a recording medium moved after development, a halogen lamp is incorporated in a belt drive roller for driving the heating belt so as to heat the heating belt by heat generated by the halogen lamp, and accordingly, the heating belt whose temperature is controlled at a predetermined temperature heats the recording sheet. With this arrangement, the conveying speed of the recording sheet and the moving speed of the heating belt are set to be equal to each other. Alternatively, the heating belt may itself generate heat.
    Type: Grant
    Filed: February 4, 1998
    Date of Patent: October 10, 2000
    Assignees: Hitachi, Ltd., Hitachi Koki Co., Ltd.
    Inventors: Hiromitsu Fukuda, Hidefumi Ohtsuka, Chikara Hiraoka, Shuho Yokokawa, Isao Nakajima, Yoji Hirose, Akihiko Yamazaki
  • Patent number: 6104907
    Abstract: There is provided an image recording apparatus which does not cause a print shift or a color drift caused by vibration and a widthwise shift due to speed variation in a conveying direction of a continuous sheet such as rolled paper or folded paper, in which a variation in speed is prevented by rollers which wind and clamp the sheet on and between an upper and a lower roller which are driven by the conveying force of the sheet, so as to prevent occurrence of vibration in the conveying direction, and a guide roller having pins adapted to be engaged in sprocket holes of the sheet are provided between the set-up positions of the tractors.
    Type: Grant
    Filed: April 27, 1998
    Date of Patent: August 15, 2000
    Assignees: Hitachi, Ltd., Hitachi Koki Co., Ltd.
    Inventors: Shigeru Obata, Hidefumi Ohtsuka, Shuho Yokokawa, Isao Nakajima, Akitomo Kuwabara
  • Patent number: 5995130
    Abstract: A laser beam scanning apparatus and method for providing controllable print density. The laser beam scanning apparatus includes a modulator for modulating a light beam, a rotating polygon mirror for deflectively scanning a light beam which is passed through the modulator, at least one lens unit having at least one lens which is movable to a position on the optical axis and a position completely off the optical axis, and a controller for switching the modulating clock frequency of the modulator and the rotating speed of the polygon mirror together with selective shifting of the at least one lens unit or lens thereof to a position on the optical axis or completely off the optical axis whereby the method effects control of the apparatus for controlling print density.
    Type: Grant
    Filed: July 24, 1996
    Date of Patent: November 30, 1999
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Kazuhiro Akatsu, Susumu Saito, Keiji Kataoka, Shuho Yokokawa, Koji Doi, Masahiro Mizuno
  • Patent number: 5881348
    Abstract: A release agent supplying member (21) is formed by release agent discharge portions (21a) for discharging release agent, and liquid level uniforming portions (21b) for uniforming a liquid level of the release agent discharged from the release agent discharge portions before supplying the release agent discharged from the release agent discharge portions to a subject to be coated.
    Type: Grant
    Filed: October 21, 1997
    Date of Patent: March 9, 1999
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Ken Onodera, Shuho Yokokawa, Kunitomo Takahashi, Hiroshi Ueno, Sho Sawahata, Tetsuya Ohba
  • Patent number: 5862436
    Abstract: A a fixing apparatus for an electrophotographic apparatus includes a heat roller (11a) having a heater (14) therein and a pressure roller (11b) urged against the heat roller, wherein a recording material (6) holding a toner image (25) thereon is sandwiched and carried while being heated and pressurized at a pressing portion between the heat roller and the pressure roller thereby to fix the toner image on a surface of the recording material, the fixing apparatus further including a first temperature detecting mechanism (18) formed by a temperature detecting element (15) provided at a portion of an outer periphery of the heat roller and a sensor head (17) disposed so as to be able oppose to the temperature detecting element, a second temperature detecting mechanism (19) formed by a plurality of temperature detecting elements disposed at a constant interval therebetween along an axial direction of the heat roller and spaced from the outer periphery of the heat roller, and a control mechanism (20, 21, 22, 23, 24)
    Type: Grant
    Filed: October 23, 1997
    Date of Patent: January 19, 1999
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Katsumi Ishizawa, Shuho Yokokawa, Satoshi Aita, Isao Watanabe, Hidenori Takayasu, Hiroshi Udo
  • Patent number: 5842098
    Abstract: In a fixing apparatus for an electrophotographic apparatus which comprises a suction apparatus (14) for attracting a rear surface of recording material (6) which continues longitudinally and holds a toner image on a major surface thereof, a preheater (10) for preheating the recording material while adhering the recording material to the preheater by attracting force of the suction apparatus, and a pair of fixing rollers (11) formed by a heat roller and a pressure roller urged to each other, wherein the recording material is sandwiched and carried while being heated and pressurized by the heat roller and the pressure roller at a pressing portion therebetween thereby to fix the toner image on the major surface of the recording material, the fixing apparatus further comprises a recording material lifting apparatus (15) having a projection member (15a) movable relative to the surface of the preheater.
    Type: Grant
    Filed: October 21, 1997
    Date of Patent: November 24, 1998
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Hiroshi Ueno, Shuho Yokokawa, Kunitomo Takahashi, Sho Sawahata, Ken Onodera, Tetsuya Ohba
  • Patent number: 5805953
    Abstract: In order to provide an indication when it is necessary to exchange toner recovery container, an electrophotographic apparatus monitors the accumulated driving time of a toner supply drive unit, and a massage indicating "exchange the toner recovery container" is displayed at the time when a toner supply switch is operated under state in which the accumulated driving time exceeds a preset value.
    Type: Grant
    Filed: November 7, 1996
    Date of Patent: September 8, 1998
    Assignee: Hitachi, Ltd.
    Inventors: Toru Kikuchi, Shuho Yokokawa, Satoshi Aita, Isao Watanabe, Hidenori Takayasu
  • Patent number: 5802444
    Abstract: An electrophotographic apparatus is provided in which toner stick hardly occurs by improving the cooling effect on the strip of paper sheets after they are heat-fixed. This electrophotographic apparatus includes a fixing unit for heating toner transferred on a continuous strip of paper sheets and fixing the toner, and a folding unit for supplying a folding force to the continuous strip of paper sheets. A conveyer unit is arranged in the back stage of the electrophotographic apparatus for transferring the continuous strip of paper sheets, received from folding unit, in the horizontal direction.
    Type: Grant
    Filed: May 5, 1997
    Date of Patent: September 1, 1998
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Youichi Takeuchi, Akihiko Yamazaki, Shuho Yokokawa, Kunitomo Takahashi, Isao Nakajima, Kazuhiro Shimojima, Shinya Yamazaki, Tomomichi Kawashima
  • Patent number: 5774777
    Abstract: An image forming apparatus includes a feed roller mechanism disposed downstream of a transfer corotron 412 constituting a transfer section and composed of driven rollers 506 located on both edges of a continuous recording medium 100 which are outside an image transfer area and a drive roller 508 extending over the whole width of the continuous recording medium 100, so that when transferring a toner image from an image recording member 402, on which the toner image is to be formed, to the continuous recording medium 100, friction by the rollers achieves reliable conveyance against an attraction between the image recording member 402 and the continuous recording medium 100 without disturbing an unfixed image on the continuous recording medium 100.
    Type: Grant
    Filed: December 30, 1996
    Date of Patent: June 30, 1998
    Assignees: Hitachi, Ltd., Hitachi Koki Co., Ltd.
    Inventors: Hidefumi Ohtsuka, Shigeru Obata, Junichi Matsuno, Yasuyuki Tsuji, Shuho Yokokawa, Isao Nakajima, Muneyoshi Akai, Yoji Hirose
  • Patent number: 5745817
    Abstract: An electrophotographic apparatus for transferring a toner image formed on a photosensitive drum onto a sheet of paper and melt-fixing the toner image on the sheet of paper, having a paper detector at a predetermined position in a transporting path of the sheet of paper, the paper detector being composed of a light projector, a reflecting member for reflecting a primary light beam emitted from the light projector and a light receiver for sensing a secondary light beam reflected by the reflecting member, to prevent erroneous detections the light receiver is placed at a position relatively displaced with respect to a position where the light projector is located so that the primary light beam and the secondary light beam have tilting components to both a plane parallel to a transporting plane of the sheet of paper and a plane vertical to the transporting plane.
    Type: Grant
    Filed: November 7, 1996
    Date of Patent: April 28, 1998
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Akihiko Yamazaki, Shuho Yokokawa, Kunitomo Takahashi, Youji Hirose, Hidenori Iwanaga
  • Patent number: 5652949
    Abstract: Preheating temperature of a preheating plate provided on the front side of a fixing unit can be changed using a temperature controller. In a case where a printing system to print images on both sides of a print member is constructed by arranging two electrophotographic printing apparatuses in dependent relationship, the preheating temperature of the preheating plate in the electrophotographic printing apparatus in the second stage is changed to a low temperature to prevent the toner image fixed in the electrophotographic printing apparatus in the first stage from softening.
    Type: Grant
    Filed: June 26, 1996
    Date of Patent: July 29, 1997
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Hiroyuki Ogawa, Shuho Yokokawa, Hiroshi Hakuta, Takao Chikuzenya, Isao Nakajima, Hiroshi Ueno
  • Patent number: 5606403
    Abstract: A toner supply control system of the electrophotographic apparatus which includes a developing unit 3 for developing with a developer composed of toner and carrier; a toner hopper 4 for storing the toner; a toner empty sensor 7 for detecting the remainder of toner in the toner hopper 4; and a toner supply drive unit 5 for conveying toner from the outside of the apparatus into the toner hopper 4. Toner is conveyed from the outside into the toner hopper 4 by driving the toner supply drive unit 5 over a predetermined period of time without stopping the operation of the electrophotographic apparatus when the toner empty sensor 7 detects over a predetermined period of time that the remainder of toner in the toner hopper 4 is small.
    Type: Grant
    Filed: November 15, 1995
    Date of Patent: February 25, 1997
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Toru Kikuchi, Shuho Yokokawa, Isao Watanabe, Satoshi Aita, Hidenori Takayasu, Shigeo Nemoto, Osamu Ohuchi, Kunitomo Takahashi, Youichi Takeuchi, Hidenori Iwanaga
  • Patent number: 5557386
    Abstract: A toner recovering device for an electrophotographic apparatus, which includes: a dust collector connected to a device for cleaning untransferred toner remaining on a photosensitive body; a toner recovering filter having an inlet port for introducing an air-toner mixture from the dust collector side and an exhaust port for filtering the air-toner mixture and discharging the air from which the toner has been removed; a filter mounting section for mounting the toner recovering filter; a joint mechanism having a joint and a hose member, one end of the hose member capable of being connected to the dust collector and other end thereof being joint, the joint being disposed at the inlet port, the joint mechanism being arranged in the filter mounting section in such a manner as to be opened and closed; a detector for sensing that the toner recovering filter has been mounted or not onto the filter mounting section; and a pulling member for coupling the inlet port of the toner recovering filter to the joint in synchron
    Type: Grant
    Filed: November 16, 1995
    Date of Patent: September 17, 1996
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Yuuji Meguro, Shuho Yokokawa, Isao Nakajima, Tsukasa Onose, Hiroshi Ueno
  • Patent number: D420042
    Type: Grant
    Filed: December 23, 1997
    Date of Patent: February 1, 2000
    Assignee: Hitachi Koki Co., Ltd.
    Inventors: Tomomichi Kawashima, Shuho Yokokawa, Kunitomo Takahashi, Tsukasa Onose, Hiroshi Hakuta