Patents by Inventor Masasumi Yahata

Masasumi Yahata 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: 6151471
    Abstract: A toner supplying device for supplying toner contained in a toner container to a developing device of an image forming apparatus includes a toner container insertion part configured to receive at least two inserted toner containers from a front side of the toner supplying device. A toner container holder detachably holds the toner containers inserted into the toner container insertion part. A toner container selection control device selects an arbitrary toner container from among the at least two toner containers held by the toner container holder and causes the selected toner container to discharge toner from an opening thereof while stopping a discharge of toner from an opening of the other toner containers.
    Type: Grant
    Filed: May 25, 1999
    Date of Patent: November 21, 2000
    Assignee: Ricoh Company, Ltd.
    Inventors: Masasumi Yahata, Shunji Katoh, Yuuji Kitajima
  • Patent number: 6118951
    Abstract: An electrophotographic image forming apparatus including a developing unit operable with a one- or two-ingredient type developer and a device for replenishing toner to the developing unit included in the apparatus are disclosed. A plurality of toner bottles are accommodated in the toner replenishing device, so that the toner is replenished from one toner bottle to the developing unit. A rotating mechanism causes all the toner bottles to rotate during toner replenishment. A device is provided for determining the frequency of use of the individual toner bottle. The toner discharged from each toner bottle is fed to a toner transport portion via a respective passageway.
    Type: Grant
    Filed: January 12, 1998
    Date of Patent: September 12, 2000
    Assignee: Ricoh Company, Ltd.
    Inventors: Shunji Kato, Masasumi Yahata, Yuji Kitajima, Noboru Kusunose
  • Patent number: 6097903
    Abstract: A toner supplying device for supplying toner contained in each of a plurality of toner containers attached to the device to a developing device of an image forming apparatus.
    Type: Grant
    Filed: August 18, 1998
    Date of Patent: August 1, 2000
    Assignee: Ricoh Company, Ltd.
    Inventors: Masasumi Yahata, Shunji Katoh, Yuuji Kitajima
  • Patent number: 6091912
    Abstract: A toner supplying device for supplying toner contained in a toner container attached to the toner supplying device to a developing device of an image forming apparatus. The toner supplying device includes a toner container insertion part configured such that a toner container is inserted therein from a front side of the toner supplying device. A toner container holder that detachably holds the toner container inserted into the toner container insertion part and toner discharged from the toner container held by the toner container holder is exhausted to a toner exhaust path. A toner delivery device delivers the toner, exhausted to the toner exhaust path, to the developing device of the image forming apparatus, by mixing the toner with air. The toner supplying device includes a covering device that covers and uncovers the toner container insertion part. The covering device includes a regulating device that regulates movement of the covering device to cover and uncover the toner container insertion part.
    Type: Grant
    Filed: January 26, 1999
    Date of Patent: July 18, 2000
    Assignee: Ricoh Company, Ltd.
    Inventors: Yuuji Kitajima, Shunji Katoh, Masasumi Yahata
  • Patent number: 5950062
    Abstract: A toner sorting device includes a device for taking in used toner conveyed from an image forming apparatus and conveying the used toner in one direction, and a device for sifting the used toner conveyed from the intake device to separate reusable toner from the used toner. The sifting device includes a tubular sieve for separating reusable toner from the used toner and a device for holding the sieve so that the sieve is rotatable. The sieve has an opening for receiving the used toner conveyed from the intake device to be moved into the sifting device and an opening for discharging the remaining toner separated from the reusable toner and remaining inside the sifting device. The toner sorting device further includes a device for collecting the reusable toner separated from the used toner by the sifting device and a device for collecting the remaining toner discharged from the sifting device. The toner sorting device further includes a device for accelerating sifting of the used toner by the sifting device.
    Type: Grant
    Filed: January 14, 1998
    Date of Patent: September 7, 1999
    Assignee: Ricoh Co., Ltd.
    Inventors: Masasumi Yahata, Shunji Katoh, Yuji Kitajima, Satoshi Takano, Shin-ichi Kawahara, Fumihito Itoh, Tsutomu Katoh
  • Patent number: 5909609
    Abstract: An image forming apparatus includes a toner bank that is configured to hold a large-volume of toner that is ultimately used to develop a latent image formed on a latent image carrier. A developing apparatus develops the latent image into a visible image. The toner is supplied to the toner bank, which need not be located adjacent to the developing apparatus, using a mechanism that prevents the toner from becoming clogged while being transported to the developing apparatus from the toner bank. In the toner bank, more than one toner bottles are vertically set. The toner bottles are individually opened and closed at respective opening portions thereon with an opening/closing mechanism and are rotated so as to discharge toner therefrom. Toner discharged from the toner bottles is dropped into the toner bank and is supplied to a developing apparatus by a flexible toner delivering mechanism having a powder pump unit and a flexible toner supplying pipe.
    Type: Grant
    Filed: June 17, 1997
    Date of Patent: June 1, 1999
    Assignee: Ricoh Company, Ltd.
    Inventors: Masasumi Yahata, Shunji Kato, Yuji Kitajima, Satoshi Takano, Nobuo Kikuchi, Shinichi Kawahara, Ryo Tanoue
  • Patent number: 5414499
    Abstract: A developing device for an image forming apparatus and operable with a developer cartridge mounted on, for example, the top of a hopper thereof. When the cartridge is inserted into a predetermined space defined in the device, it forms a clearance having a predetermined sectional area and extending in the direction of cartridge insertion in cooperation with a wall that delimits the space. Hence, air inside the space is forced out to the outside via the clearance which terminates at a cartridge inlet. A filter is affixed to the outer periphery of at least the leading end portion of the cartridge, with respect to the direction of cartridge insertion, in such a manner as to block the clearance. As a result, when air flows through the clearance, a toner entrained by the stream of air is caught by the filter.
    Type: Grant
    Filed: December 22, 1993
    Date of Patent: May 9, 1995
    Assignee: Ricoh Company, Ltd.
    Inventor: Masasumi Yahata
  • Patent number: 5260749
    Abstract: A toner cartridge for supplying a toner to the toner hopper of a developing apparatus incorporated in image forming equipment. A take-up roller is rotatably mounted on a case which stores a toner therein. A seal member covers an opening formed in the bottom of the case and is affixed to the take-up roller at one end thereof. The seal member is automatically attached to and detached from the case without resorting to manual operations.
    Type: Grant
    Filed: October 18, 1991
    Date of Patent: November 9, 1993
    Assignee: Ricoh Company, Ltd.
    Inventor: Masasumi Yahata
  • Patent number: 5202732
    Abstract: A developing device incorporated in image forming equipment and having a toner tank made up of a tank portion and a toner supply portion contiguous with one side of the tank portion for supplying the toner from the tank portion to a developing section which includes a developing roller. The tank portion accommodates a bladed wheel having blades therein while the toner supply portion has a projection which protrudes into the radius of rotation of the blades. As the blades are rotated, the projection scrapes off the toner deposited on the blades to thereby feed it into the toner supply portion. The radius of rotation of the blades is substantially equal to or smaller than the inner radius of the tank portion, whereby the blades are prevented from pressing against the tank portion.
    Type: Grant
    Filed: February 12, 1992
    Date of Patent: April 13, 1993
    Assignee: Ricoh Company, Ltd.
    Inventor: Masasumi Yahata
  • Patent number: 4982223
    Abstract: A developing device for an image forming apparatus having a plurality of developing sleeves which are arranged one above the other in a predetermined relationship along the surface of an image carrier of the apparatus, and developing a latent image electrostatically formed on the image carrier by using a toner contained in a developer. While a paddle wheel scoops up the developer, a developer guide guides the scooped developer to the uppermost developing sleeve. The developer fed by the paddle wheel toward the lowermost developing sleeve is received by the guide member and driven therealong to the uppermost developing sleeve and not to the lowermost sleeve.
    Type: Grant
    Filed: December 14, 1989
    Date of Patent: January 1, 1991
    Assignee: Ricoh Company, Ltd.
    Inventor: Masasumi Yahata