Patents by Inventor Eizi Takenaka

Eizi Takenaka 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).

  • Developing apparatus for electronic photographic recording equipment, having two developer transfer rollers
    Patent number: 5689782
    Abstract: A developing apparatus is capable of providing stable charging ability for a developer and stable transfer ability for transferring the developer to a photoreceptor for electronic photography to prevent residual positive images and stain of texture which appear on a toner image. A first toner transfer roller 23 has a core supported to be rotatable and a sheet type insulation layer wound around the outer periphery of the core. The insulation layer is made of elastic rubber in which magnetic material having a specified particle size is uniformly dispersed and the magnetic material is formed with ferromagnetic substance such as magnet and magnetized in advance. The first toner transfer roller 23 attracts toner T by actuating magnetism on the insulation layer since the magnetic material added to the insulation layer is magnetized.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: November 18, 1997
    Assignee: Ricoh Company, Ltd.
    Inventors: Eisaku Murakami, Kazuhiro Yuasa, Shuichi Endoh, Iwao Matsumae, Yoshiaki Tanaka, Hiroshi Hosokawa, Mugiziroh Uno, Hiroshi Saitoh, Eizi Takenaka, Toshihiro Sugiyama, Tetsuo Yamanaka, Satoru Komatsubara