Patents by Inventor Masato Ishii

Masato Ishii 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: 5221952
    Abstract: An electrophotographic recording apparatus including a light-sensitive drum for carrying toner images developed thereon, and a transfer unit arranged at a prescribed distance from the light-sensitive drum for transferring the toner images from a light-sensitive drum to the image recording paper. The transfer unit has a charging wire electrode for electrically charging the paper and a generally inverted U-shaped housing having spaced sidewalls with respective bottom edges. A separator is provided for separating the paper from the light-sensitive drum as the paper travels along a conveying path and comprises a paper separating plate extending from the downstream one of the bottom edges of the housing of the transfer unit in the downstream direction of the travel of the paper along the conveying path side thereof, with and the housing of the transfer unit is grounded. The paper separating plate has a distal end having a saw tooth shape along the length thereof, as measured transversely to the conveying path.
    Type: Grant
    Filed: August 24, 1992
    Date of Patent: June 22, 1993
    Assignee: Fujitsu Limited
    Inventors: Masato Ishii, Masanori Tokuhisa, Hirohiko Kubo
  • Patent number: 5214475
    Abstract: An image forming apparatus includes a developing unit and a photoconductive drum. A toner sensor is disposed in a toner mixing chamber of the developing unit. A mixing member is included in the chamber for mixing and frictionally charging the toner. A detection device is mounted on the unit for detecting the residual quantity of density of the toner according to the output voltage of the sensor. The residual quantity or density of the toner is detected by sampling an output voltage of the toner sensor at predetermined times during a predetermined period while the mixing member is rotated at a specific constant speed, and averaging the sampled vales. As a result correct data for the residual quantity or density of the toner can be obtained.
    Type: Grant
    Filed: November 13, 1991
    Date of Patent: May 25, 1993
    Assignee: Fujitsu Limited
    Inventors: Masato Ishii, Hirohiko Kubo