Patents by Inventor Hiroyuki Tsujinaka, deceased

Hiroyuki Tsujinaka, deceased 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: 5944621
    Abstract: The present invention provides a hollow golf ball having a spherical cavity in the center, which exhibits excellent durability and less impact strength to result in excellent shot feel without degrading flight performance, and the production of the same. The hollow golf ball includes: (a) hollow center formed from a material selected from the group consisting of rubber, thermoplastic resin and a mixture thereof, the hollow center having a hollow portion with a diameter of 5 to 30 mm; (b) at least one core rubber layer, formed on said hollow center, the core rubber layer being obtained by vulcanizing a rubber composition which comprises a base rubber, a metal salt of an unsaturated carboxylic acid, an organic peroxide and filler; and (c) a cover formed on said core rubber layer.
    Type: Grant
    Filed: October 30, 1997
    Date of Patent: August 31, 1999
    Assignee: Sumitomo Rubber Industries, Ltd.
    Inventors: Hiroyuki Tsujinaka, deceased, Minoru Tsujinaka, legal representative, Kinuko Tsujinaka, legal representative, Kazuo Hochi, Masaya Tsunoda, Keiji Moriyama, Kiyoto Maruoka