Patents by Inventor Yoshimitu Nakashima

Yoshimitu Nakashima 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: 6783439
    Abstract: A method for manufacturing a mirror surface tube for a photosensitive drum of a copying machine or the like, by which an external surface of an aluminium or aluminium alloy tube can be mirror-processed with high accuracy without surface defects, and in such a way that good quality required for a photosensitive drum is ensured and dimension accuracy, such as roundness, and production yield is improved involves a first step in which an aluminium or aluminium alloy tube, finished in a predetermined shape and dimension with surface roughness of 10 microns or less, is processed by a centerless grinding process. Then, in a second step, a grinding process is performed using an electrolytic integrated polishing apparatus including a tool electrode mechanism having an elastic grindstone so as to make a mirror surface tube having the surface roughness of 2.0 microns or less. Further, preferably, in a third stage, a roller burnishing process is performed to finish the tube to a surface roughness of 0.5 microns or less.
    Type: Grant
    Filed: October 14, 1999
    Date of Patent: August 31, 2004
    Assignee: Nissin Unyu Kogyo Co., Ltd.
    Inventors: Kazuo Akagi, Akira Hashimoto, Yoshimitu Nakashima
  • Patent number: 6322426
    Abstract: A method for mirror processing of an external surface of a long-sized metal piece, by which the external surface is mirror-polished with precision and high efficiency without a surface defect or so that stable dimensional accuracy, such as a roundness and improvement of yield in production, can be obtained. The method comprises the steps of clamping both ends of a long-sized metal piece, applying a positive electrical charge and rotating the metal piece, and moving the long-sized metal in the axial direction through an electrolytic integrated polishing apparatus for processing the external surface of a long-sized metal piece into a mirror surface.
    Type: Grant
    Filed: October 14, 1999
    Date of Patent: November 27, 2001
    Assignee: Nissin Unyu Kogyo Co., Ltd.
    Inventors: Kazuo Akagi, Tomohisa Akiyoshi, Yoshimitu Nakashima