Patents by Inventor Katsuaki Miyawaki

Katsuaki Miyawaki 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).

  • Publication number: 20040057059
    Abstract: An electrophotographic image forming apparatus of the present invention includes a photoconductive drum provided with a photoconductive layer on its surface. A charger uniformly charges the surface of the drum while an exposing unit exposes the charged surface of the drum to thereby form a latent image on the drum. A developing device develops the latent image with toner by feeding the toner to the drum to thereby produce a corresponding toner image and collects residual toner left on the drum after image transfer. An image transferring device transfer the toner image from the drum to an intermediate image transfer body. An air conditioning unit sends dehumidified, air-controlled air to a space around said photoconductive element.
    Type: Application
    Filed: July 3, 2003
    Publication date: March 25, 2004
    Inventors: Tetsuroh Miura, Katsuaki Miyawaki, Takeshi Saitou, Takeo Suda, Yasushi Nakazato, Yasuo Suzuki
  • Publication number: 20040013442
    Abstract: An electrophotographic image forming apparatus of the present invention includes a frame, a photoconductive drum disposed in the frame, and an air conditioning device for removing moisture around the drum inside the frame. The drum has a wear-resistant, durable surface layer that wears by an amount of 0.05 &mgr;m to 0.5 &mgr;m for 100,000 rotations.
    Type: Application
    Filed: June 13, 2003
    Publication date: January 22, 2004
    Inventors: Yasuo Suzuki, Satoshi Igari, Katsuaki Miyawaki, Yasushi Nakazato, Takeo Suda, Tetsuroh Miura, Takeshi Saitou
  • Publication number: 20030185602
    Abstract: An image forming apparatus suppresses several kinds of inconveniences caused by unnecessary contact of a belt-formed member with opposing members and drives the belt-formed member accurately even when the belt-formed member separated from a part of a plurality of opposing members. In an image forming apparatus having a belt-formed member supported by a plurality of supporting rollers and a plurality of opposing members located side by side in a line to oppose and contact the belt-formed member, a pivot mechanism is employed to temporarily separate the belt-formed member from a part of the opposing members for color image formation. The image forming apparatus also includes a tension roller dive mechanism to increase a relative distance between the tension roller and other supporting rollers to suppress a decrease in a tension of the belt-formed member during the above-described separation of the belt-formed member from the plurality of opposing members.
    Type: Application
    Filed: March 26, 2003
    Publication date: October 2, 2003
    Inventors: Tetsurou Sasamoto, Katsuaki Miyawaki, Makoto Obu, Minoru Suzuki, Yuichi Aoyama
  • Patent number: 6556802
    Abstract: An image forming apparatus suppresses several kinds of inconveniences caused by unnecessary contact of a belt-formed member with opposing members and drives the belt-formed member accurately even when the belt-formed member separated from a part of a plurality of opposing members. In an image forming apparatus having a belt-formed member supported by a plurality of supporting rollers and a plurality of opposing members located side by side in a line to oppose and contact the belt-formed member, a pivot mechanism is employed to temporarily separate the belt-formed member from a part of the opposing members for color image formation. The image forming apparatus also includes a tension roller dive mechanism to increase a relative distance between the tension roller and other supporting rollers to suppress a decrease in a tension of the belt-formed member during the above-described separation of the belt-formed member from the plurality of opposing members.
    Type: Grant
    Filed: October 1, 2001
    Date of Patent: April 29, 2003
    Assignee: Ricoh Company, Ltd.
    Inventors: Tetsurou Sasamoto, Katsuaki Miyawaki, Makoto Obu, Minoru Suzuki, Yuichi Aoyama
  • Publication number: 20020044799
    Abstract: An image forming apparatus suppresses several kinds of inconveniences caused by unnecessary contact of a belt-formed member with opposing members and drives the belt-formed member accurately even when the belt-formed member separated from a part of a plurality of opposing members. In an image forming apparatus having a belt-formed member supported by a plurality of supporting rollers and a plurality of opposing members located side by side in a line to oppose and contact the belt-formed member, a pivot mechanism is employed to temporarily separate the belt-formed member from a part of the opposing members for color image formation. The image forming apparatus also includes a tension roller dive mechanism to increase a relative distance between the tension roller and other supporting rollers to suppress a decrease in a tension of the belt-formed member during the above-described separation of the belt-formed member from the plurality of opposing members.
    Type: Application
    Filed: October 1, 2001
    Publication date: April 18, 2002
    Inventors: Tetsurou Sasamoto, Katsuaki Miyawaki, Makoto Obu, Minoru Suzuki, Yuichi Aoyama
  • Publication number: 20020031379
    Abstract: A tandem image forming device for an image forming apparatus of the present invention includes a plurality of image forming means arranged side by side along an intermediate image transfer belt. The image forming means each include a developing device and a cleaning device arranged around an image carrier. One of nearby image forming means has its cleaning devise positioned above the developing device of the other image forming means, e.g., an agitating section forming part of the image forming means. This configuration insures smooth circulation of a developer and therefore obviates an irregular developer distribution while reducing the overall size of the image forming device.
    Type: Application
    Filed: September 14, 2001
    Publication date: March 14, 2002
    Applicant: Ricoh Company, Ltd.
    Inventors: Katsuaki Miyawaki, Takeshi Iijima, Yusuke Takeda, Shuji Hirai, Sadayuki Iwai, Hideki Kosugi, Makoto Obu
  • Patent number: 6324374
    Abstract: An image forming apparatus suppresses several kinds of inconveniences caused by unnecessary contact of a belt-formed member with opposing members and drives the belt-formed member accurately even when the belt-formed member separated from a part of a plurality of opposing members. In an image forming apparatus having a belt-formed member supported by a plurality of supporting rollers and a plurality of opposing members located side by side in a line to oppose and contact the belt-formed member, a pivot mechanism is employed to temporarily separate the belt-formed member from a part of the opposing members for color image formation. The image forming apparatus also includes a tension roller dive mechanism to increase a relative distance between the tension roller and other supporting rollers to suppress a decrease in a tension of the belt-formed member during the above-described separation of the belt-formed member from the plurality of opposing members.
    Type: Grant
    Filed: May 31, 2000
    Date of Patent: November 27, 2001
    Assignee: Ricoh Company, Ltd.
    Inventors: Tetsurou Sasamoto, Katsuaki Miyawaki, Makoto Obu, Minoru Suzuki, Yuichi Aoyama
  • Patent number: 6108508
    Abstract: In an image forming apparatus, a developing device includes a reservoir storing a viscous and dense developing liquid. A developing sleeve, an applicator roller, a circulation pump for circulating the liquid and a screw for agitating the liquid are disposed in the reservoir. The reservoir is open only at its portion where the developing sleeve contacts an image carrier. The liquid is agitated by the screw before flowing into the circulation pump and then applied to the applicator roller. As a result, the liquid is fed to the developing sleeve via the applicator roller with a uniform toner content. The apparatus is small size and stably forms high quality images.
    Type: Grant
    Filed: December 30, 1998
    Date of Patent: August 22, 2000
    Assignee: Ricoh Company, Ltd.
    Inventors: Noriyasu Takeuchi, Masahiko Itaya, Yuichi Aoyama, Katsuaki Miyawaki, Makoto Obu, Mie Yoshino
  • Patent number: 5848329
    Abstract: An image forming apparatus including a plurality of image forming units or process units is disclosed. The process units may each be moved into and out of the body of the apparatus by hand. A plurality of support members for supporting the ends of the process units to be operated by hand extend substantially parallel to a linear path for conveying a recording medium, but outside of paths for moving the process units into and out of the apparatus body. A positioning mechanism positions the above end of the individual process unit relative to the support members. The positioning mechanism is implemented by holes formed in the support members, and pins studded on a positioning wall included in the individual process unit. The apparatus allows the process units to be positioned thereon accurately with a high mechanical strength, while allowing them to be mounted and dismounted with ease.
    Type: Grant
    Filed: April 2, 1997
    Date of Patent: December 8, 1998
    Assignee: Ricoh Company, Ltd.
    Inventors: Yuichi Aoyama, Makoto Obu, Masaki Hiroi, Katsuaki Miyawaki, Nobuhiko Umezawa, Masami Hiramatsu
  • Patent number: 5708938
    Abstract: A wet process image forming apparatus using a developing liquid consisting of a carrier liquid and a toner dispersed therein, in which air containing carrier vapor produced in, e.g., a fixing section, is sucked by a suction fan via a first duct into a liquefying section. The liquefying section liquefies the carrier vapor and water vapor. A separating section is disposed below the liquefying portion and includes a receptacle. A liquid produced by the liquefying section is caused to flow down into the receptacle along a chain due to its own weight. The separating section separates the liquid into the carrier liquid and water on the basis of a difference in specific gravity. Only the carrier overlying the water in the receptacle is fed to a carrier tank via overflow ports formed in the wall of the receptacle. The water is delivered to a water tank via a pipe. The pipe is so configured as to maintain the liquid level in the receptacle substantially at the level of the overflow ports.
    Type: Grant
    Filed: December 14, 1995
    Date of Patent: January 13, 1998
    Assignee: Ricoh Company, Ltd.
    Inventors: Noriyasu Takeuchi, Tsuneo Kurotori, Masakazu Muranaka, Katsuaki Miyawaki, Toshio Inada, Yusuke Takeda, Sadayuki Iwai, Kozoh Sudoh
  • Patent number: 5612278
    Abstract: A recording method of forming images on a reversible thermosensitive recording material, by bringing a heating element of a thermal head into pressure contact with the reversible thermosensitive recording material, which is capable of assuming a first colored state when heated to a first temperature which is higher than room temperature, and then cooled, and which is capable of assuming a second colored state when heated to a second temperature which is higher than the first temperature, and then cooled, and relatively moving at least one of the heating element or the reversible thermosensitive recording material, wherein the stress exerted on the reversible thermosensitive recording material per unit area thereof, .sigma.(g/cm.sup.2), which is generated by the pressure contact of the heating element with the reversible thermosensitive recording material and the relative movements of the heating material and the reversible thermosensitive recording material, is represented by formula (I):.sigma..ltoreq.
    Type: Grant
    Filed: July 25, 1994
    Date of Patent: March 18, 1997
    Assignee: Ricoh Company, Ltd.
    Inventors: Fumihito Masubuchi, Yoshihiko Hotta, Yusuke Takeda, Makoto Obu, Toshio Kawakubo, Katsuaki Miyawaki, Tetsuya Amano
  • Patent number: 5379058
    Abstract: A recording apparatus for recording data in a thermosensitive recording medium. The recording medium has a reversible thermosensitive recording material capable of selectively assuming one of two visible states, e.g., a cloudy state and a transparent state or a colored state and a decolored state when heated. The thermosensitive material is applied to a sheet of resin. The apparatus surely erases data written in the medium with no regard to the time elapsed and the number of times that data has been repetitively written. The cloud density or the color density is prevented from changing with no regard to the storage temperature, the time elapsed, or the number of times of writing, thereby preventing image quality from being degraded. In addition, the medium has a long service life.
    Type: Grant
    Filed: March 17, 1993
    Date of Patent: January 3, 1995
    Assignee: Ricoh Company, Ltd.
    Inventors: Makoto Obu, Yoshihiko Hotta, Fumihito Masubuchi, Katsuaki Miyawaki, Yusuke Takeda, Toshio Kawakubo
  • Patent number: 5371522
    Abstract: An apparatus for recording data in a thermosensitive recording medium at a first temperature after erasing data written in the medium at a second temperature. The apparatus desirably erases data stored in a recording medium with no regard to the time elapsed after writing, condition of storage, writing conditions, the number of repetitive writing and erasing operations, etc.
    Type: Grant
    Filed: March 17, 1993
    Date of Patent: December 6, 1994
    Assignee: Ricoh Company, Ltd.
    Inventors: Katsuaki Miyawaki, Yusuke Takeda, Toshio Kawakubo, Makoto Obu, Yoshihiko Hotta, Fumihito Masubuchi
  • Patent number: 5300952
    Abstract: Image forming equipment for applying heat to a charged image carrier to attenuate part of the potential of the image carrier in order to form a latent image on the image carrier. The surface of a dielectric image carrier is charged by a charger and a thermal print head is driven in response to image information in order to form a latent image on the charged surface of the image carrier. A developing roller applies a liquid developer to the latent image and presses it against the portion where the potential has been lowered. The resulting toner image formed on the image carrier is fixed on a paper sheet fed from a paper feeding device or is directly fixed on the image carrier. The image carrier is formed of polyethylene terephthalate or a mixture of polybutylene terephthalate and silicon dioxide.
    Type: Grant
    Filed: October 25, 1991
    Date of Patent: April 5, 1994
    Assignee: Ricoh Company, Ltd.
    Inventors: Takeo Wada, Makoto Obu, Toshiyuki Kawanishi, Noriyoshi Tarumi, Masato Igarashi, Takashi Mori, Katsuaki Miyawaki, Minoru Suzuki
  • Patent number: 5220355
    Abstract: A resistive sheet thermal transfer printer includes a plurality of recording electrodes in in contact with a resistance layer of a current sensitized ink sheet, a common electrode in contact with the resistance layer of the current sensitized ink sheet, and a power supply for applying a voltage across the common electrode and each of the recording electrodes in accordance with image data. The resistive sheet thermal transfer printer also includes, a detection circuit for detecting an electrical current passing through each of the recording electrodes when a predetermined voltage is supplied to each of the recording electrodes, a control circuit for determining, based on a detected electric current obtained by the detection circuit, whether or not a deposit has accumulated on at least one of the recording electrodes, and an abrasive mechanism for abrading ends of the recording electrodes when the control circuit determines that the deposit has accumulated on at least one of the recording electrodes.
    Type: Grant
    Filed: April 7, 1992
    Date of Patent: June 15, 1993
    Assignee: Ricoh Company, Ltd.
    Inventor: Katsuaki Miyawaki