Patents by Inventor Hironobu Takasawa

Hironobu Takasawa 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: 20020002915
    Abstract: A multicolor printing method using a plurality of ink drums each being loaded with a respective master and a system therefore are disclosed. A plurality of removable ink drums replaceable with each other are fed with respective masters by fixed master feeding devices smaller in number than ink drums via the replacement of the drums and are used for printing. The method and system of the present invention are low cost and enhance downsizing and accurate registration between the masters.
    Type: Application
    Filed: October 1, 1998
    Publication date: January 10, 2002
    Inventors: HIRONOBU TAKASAWA, MANABU WAKAMATSU
  • Publication number: 20010047731
    Abstract: A printer of the present invention includes drive pulleys each being mounted on a particular print drum.
    Type: Application
    Filed: March 1, 2001
    Publication date: December 6, 2001
    Applicant: Tohoku Ricoh Co., Ltd
    Inventors: Keiichi Chiba, Hironobu Takasawa
  • Patent number: 6314877
    Abstract: In a printer including a plurality of print drums sequentially arranged in a direction of sheet conveyance, a member causative of noticeable variation in load during printing is driven by a driveline assigned to one print drum that is connected to a main drive source. The printer reduces synchronization errors between the print drums ascribable to variation in load and therefore reduces offset ghosts while making the most of the advantages of a timing belt type drive system.
    Type: Grant
    Filed: June 27, 2000
    Date of Patent: November 13, 2001
    Assignee: Tohoku Ricoh Co., Ltd.
    Inventor: Hironobu Takasawa
  • Publication number: 20010029850
    Abstract: A printer of the present invention includes a timing belt passed over drive pulleys, each of which is mounted on a particular print drum, via phase adjusting means and deflection pulleys or rotary members. The deflection pulleys are rotatable in contact with the rear surface of the timing belt. The timing belt has its rear surface ground to have uniform thickness. The printer is free from the deviation of relative phase between the rotary members and offset ghosts ascribable to the irregular thickness of the timing belt, while preserving the low-cost configuration of timing belt connection.
    Type: Application
    Filed: February 28, 2001
    Publication date: October 18, 2001
    Applicant: Tohoku Ricoh Co., Ltd.
    Inventors: Keiichi Chiba, Hironobu Takasawa
  • Patent number: 6129013
    Abstract: A stencil printer of the present invention includes at least one ink drum for wrapping a master around its outer periphery. An ink feed device feeds ink to the master wrapped around the ink drum. A pressing member is movable into and out of contact with the ink drum at a position where it faces the ink feed device. An image is printed on a paper fed from a paper feed section at a print section where the ink drum and pressing member face each other. A belt conveyor includes a belt extending between the paper feed section located upstream of the print section in the direction of paper conveyance and a paper discharge section located downstream of the print section in the same direction through the print section. The belt conveys the paper fed from the paper feed section while causing it to electrostatically adhere thereto. The paper is sufficiently electrostatically adhered to the belt before it reaches the print section, so that air suction, an air knife, a separator or the like is not necessary.
    Type: Grant
    Filed: September 9, 1998
    Date of Patent: October 10, 2000
    Assignee: Tohoku Ricoh Co., Ltd.
    Inventors: Hironobu Takasawa, Mituru Takahashi, Naoki Okazaki
  • Patent number: 5845571
    Abstract: A method of printing a document image on a paper by wrapping a stencil, or master, perforated by, for example, a thermal head around a print drum, and a stencil printer. A wedge effect occurs between the print drum and an ink roller disposed in the print drum. The wedge effect, coupled with the pressure of a pressing member, causes ink to exude from the inner periphery to the outer periphery of the print drum and further from the master to the paper. The paper is separated from the master at a position downstream, with respect to the direction of rotation of the print drum, of a portion where the ink exudes due to the wedge effect. At the paper separating position, the ink does not exude from the master, and the ink pressure does not act. This obviates the blur of a printed image and prevents the ink from being transferred from the front of an underlying printing sheet to the rear of an overlying printing sheet stacked on the underlying sheet due to excessive ink transfer.
    Type: Grant
    Filed: January 24, 1997
    Date of Patent: December 8, 1998
    Assignees: Michio Kurashige, Tohoku Ricoh Co., Ltd.
    Inventors: Michio Kurashige, Hironobu Takasawa, Tomiya Mori
  • Patent number: 4846057
    Abstract: In a screen printing machine, its printing-plate discharge unit is provided with: a pair of printing-plate discharge rollers which may approach to a peripheral surface of a plate cylinder and may also draw therefrom; and a waste-paper container for receiving a waste printing plate having been peeled from the peripheral surface of the plate cylinder. In the waste-paper container is provided a waste printing-plate compression plate which is vertically movable in the waste-paper container. The compression plate is moved up and down in the waste-paper container by means of an operation means which is provided in a position outside the waste-paper container. The compression plate compresses the waste printing plate in the waste-paper container when moved downward therein.
    Type: Grant
    Filed: September 1, 1987
    Date of Patent: July 11, 1989
    Assignee: Ricoh Co., Ltd.
    Inventors: Toshio Endo, Takashi Miyagi, Mitsuo Sato, Hironobu Takasawa, Hiroshi Kanno, Keiichi Miyakawa, Masao Takano, Tomoya Ito