Patents by Inventor Kaisaburo Shigematsu

Kaisaburo Shigematsu 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).

  • Mask
    Patent number: 4501272
    Abstract: A mask in which an enclosure of an intake filtration chamber is partly or totally formed of a filtration medium so that a separate filtration medium need not be provided within the intake filtration chamber for replacement. The replacement of the filtration medium is effected by replacement of the entire intake filtration chamber. The invention provides a mask which is small in size and low in intake resistance and is free from a possible flow of contaminated air into the mask.
    Type: Grant
    Filed: October 28, 1982
    Date of Patent: February 26, 1985
    Assignee: Shigematsu Works Co., Ltd.
    Inventors: Kaisaburo Shigematsu, Nobuo Shigematsu, Yukio Okubo