Patents by Inventor Yasushi Nagatomo

Yasushi Nagatomo 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: 4927990
    Abstract: A push-button switch comprises a fixed electrode; a movable electrode disposed opposite to the fixed electrode; a key housing having a tubular spring retainer, and an annular guide wall surrounding the tubular spring retainer and having a stopping flange, a coil spring received in the tubular spring retainer, and a key for operating the movable electrode through the coil spring. The coil spring has a large coil section, a middle extension coil section, and a small compression coil section having a projecting part. The tubular spring retainer is provided with a protrusion on the inner circumference thereof. When the key is depressed to close the switch, the projecting part of the coil spring is forced to move down over the protrusion in a snap motion, and the projecting part is forced to move up over the protrusion by the contractive force of the middle extension coil section and the recoiling force of the small compression coil section of the coil spring when the key is released.
    Type: Grant
    Filed: March 3, 1989
    Date of Patent: May 22, 1990
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Kazuo Aoki, Toshimi Chiba, Sadao Tachibana, Yasushi Nagatomo