Patents by Inventor Masakazu Ishikawa

Masakazu Ishikawa 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: 4016533
    Abstract: A device for warning of the occurrence of excessive wear on the brake lining of a brake for a vehicle, in which a detecting element for detecting an increase in the amount of wear on the lining from a predetermined value is mounted on a rear plate supporting the lining, a part of the detecting element projects from the rear plate to the outside of the brake, and a metallic cylindrical cover is fixed to the rear plate so as to cover said projecting part of the detecting element, thereby preventing foreign material from contacting the detecting element when the vehicle is in operation.
    Type: Grant
    Filed: October 21, 1974
    Date of Patent: April 5, 1977
    Assignee: Toyota Jidosha Kogyo Kabushiki Kaisha
    Inventors: Masakazu Ishikawa, Sadayoshi Ito, Hiroyuki Oka, Kennoske Iida, Kenji Usui, Masayoshi Asaba
  • Patent number: 4005401
    Abstract: An electric switch for use in a braking fluid pressure fault alarm device for a vehicular dual brake system, which device includes a body having a cylinder, a piston slidably inserted in the cylinder and receiving front and rear wheel braking fluid pressures for sliding movement from its inoperative position to its operative position in response to leakage of either of the braking fluid pressures, and an electric alarm circuit for generating an alarm signal when deenergized. The electric switch is engaged with the piston and is switched from its conductive condition to its non-conductive condition in response to sliding movement of the piston in order to deenergize the electric alarm circuit.
    Type: Grant
    Filed: May 21, 1975
    Date of Patent: January 25, 1977
    Assignee: Toyota Jidosha Kogyo Kabushiki Kaisha
    Inventors: Masakazu Ishikawa, Takaaki Ota, Noriakira Ishigami, Asao Kozakai
  • Patent number: 3986164
    Abstract: A warning mechanism for detecting brake shoe wear is adapted to be fitted into a recess formed on the rear face of a brake shoe such that when the front face of the shoe, which undergoes frictional engagement during braking, is worn to a sufficient extent, a defaceable detection wire in the warning mechanism will be ruptured to provide an indication of depletion of the braking material of the shoe. The detector element is removably secured within the recess of the brake shoe and is located such that it will not be dislodged by a braking force applied to the brake shoe by a piston of the brake assembly but will, instead, be held in position thereby.
    Type: Grant
    Filed: August 26, 1974
    Date of Patent: October 12, 1976
    Assignees: Toyota Jidosha Kogyo Kabushiki Kaisha, Sumitomo Denki Kogyo K.K.
    Inventors: Akiyoshi Hirai, Masakazu Ishikawa, Sadayoshi Ito, Takeshi Noguchi
  • Patent number: 3981147
    Abstract: In a combined reservoir made of a plastic material such as nylon or polythene and master cylinder housing assembly, a bolt is screwed into coaxial openings of the housing and the reservoir to fasten each other. A metallic sleeve is secured to the opening of the plastic reservoir to limit the compression of plastic reservoir when the bolt is rotated. Thus, a seal rubber provided between the plastic reservoir and the housing is properly compressed to make effectively fluid-tight therebetween due to a proper fastening force exerted on the metallic sleeve.
    Type: Grant
    Filed: August 1, 1975
    Date of Patent: September 21, 1976
    Assignees: Aisin Seiki Kabushiki Kaisha, Toyota Jidosha Kogyo Kabushiki Kaisha
    Inventors: Masashi Ban, Masakazu Ishikawa, Hiroshi Uemura
  • Patent number: 3980987
    Abstract: Apparatus for providing an indication to a vehicle operator of failure of either of separated fluid braking circuits by means of an electric circuit, which electric circuit is further enabled to provide such indication in response to self-deactuation of the electric circuit.
    Type: Grant
    Filed: December 2, 1974
    Date of Patent: September 14, 1976
    Assignees: Aisin Seiki Kabushiki Kaisha, Toyota Jidosha Kogyo Kabushiki Kaisha
    Inventors: Noriakira Ishigami, Asao Kozakai, Masakazu Ishikawa, Takaaki Ota