Patents by Inventor Masaki Tokuhashi

Masaki Tokuhashi 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: 5396319
    Abstract: A cleaning device for an image forming apparatus in which a shock generation device is provided for imparting an impact force to a cleaning blade in an axial direction of a photoconductive member in order to prevent an edge portion of the cleaning blade from accumulating debris such as minute paper powder and toner, and thereby maintain a high quality image. The cleaning device can be controlled so that operation of the shock generation device for providing an impact force to the cleaning blade starts simultaneously as revolution of a photoconductive member starts, such that the foreign materials are effectively removed from a cleaning blade.
    Type: Grant
    Filed: September 22, 1993
    Date of Patent: March 7, 1995
    Assignee: Ricoh Company, Ltd.
    Inventors: Masaki Tokuhashi, Makoto Arai, Masato Yanagida, Toshitaka Yamaguchi, Hiroshi Ono
  • Patent number: 5258248
    Abstract: An image density control method for an image forming apparatus of the type forming a latent image of a document image on a photoconductive element and developing the latent image by a toner to produce a toner image by an electrophotographic procedure. A background pattern whose density is substantially the same as the background density of a document, i.e., a light pattern is illuminated to electrostatically form a latent image thereof on the photoconductive element. The latent image is developed by the toner, and the density of the resultant toner image is optically sensed by an image density sensor. A change in background density due to contamination or an increase in background potential, for example, is detected. Based on the detected change in background density, a quantity of light for imagewise exposure or similar factor dictating the developing ability is corrected, i.e., it is controlled to the light side if the density has been shifted to the dark side.
    Type: Grant
    Filed: April 7, 1992
    Date of Patent: November 2, 1993
    Assignee: Ricoh Company, Ltd.
    Inventors: Masaki Tokuhashi, Moriyuki Koike, Wataru Yasuda, Kouji Ishigaki, Takashi Bisaiji, Chikara Imai
  • Patent number: 5028960
    Abstract: An image density control method for an image forming apparatus of the type forming a latent image of a document image on a photoconductive element and developing the latent image to form a toner image by an electrophotographic procedure. A background pattern is implemented as a light pattern having a low density and provided independently of a reference density pattern. The light pattern is illuminated to form a latent image thereof on the photoconductive element, and the latent image is developed by a toner. The density of the resultant toner image is sensed by an image density sensor. Such a procedure allows a change in background density ascribable to contamination, increase in background potential and so forth to be detected. The light pattern may be replaced with a leading edge portion of a document if the leading edge portion has a density corresponding to the background density.
    Type: Grant
    Filed: April 10, 1990
    Date of Patent: July 2, 1991
    Assignee: Ricoh Company, Ltd.
    Inventors: Wataru Yasuda, Moriyuki Koike, Masaki Tokuhashi, Kouji Ishigaki, Yoshihiro Abe