Patents by Inventor Toshiki Oonaka

Toshiki Oonaka 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).

  • Publication number: 20020045490
    Abstract: A hollow golf club head made of a metallic material. The golf club head has a three piece structure, a main head body, face, and crown. The main head body and the crown are formed by casting or press-forming, the face is formed by press-forming, and these are joined together by welding. The metallic material used is selected from a steel material group of martensite deposition hardening-type stainless steel, maraging steel, and maraging stainless steel. Only a material having a specific gravity of 7.7 or higher is used, and the head body has a volume of 280-320 cc and a weight of 180-205 g. The golf club head enables increasing the meet rate, has design freedom, exhibits excellent processability, and can be manufactured at a low cost.
    Type: Application
    Filed: November 2, 2001
    Publication date: April 18, 2002
    Applicant: G.P.S. CO., LTD.
    Inventors: Hiroyuki Ezawa, Toshiki Oonaka, Sadayoshi Furusawa, Shingo Nomura, Takashi Iihara
  • Patent number: 6334817
    Abstract: A hollow golf club head made of a metallic material. The golf club head has a three piece structure of a main head body, face and crown. The main head body and the crown are formed by casting or press-forming, the face is formed by press-forming, and these are joined together by welding. The metallic material used is selected from a steel material group of martensite deposition hardening-type stainless steel, maraging steel, and maraging stainless steel. Only a material having a specific gravity of 7.07 or higher is used, and the head body has a volume of 280-320 cc and a weight of 180-205 g. The golf club head enables increasing the meet rate, has design freedom, exhibits excellent processability, and can be manufactured at a low cost.
    Type: Grant
    Filed: December 29, 1999
    Date of Patent: January 1, 2002
    Assignee: G.P.S. Co., Ltd.
    Inventors: Hiroyuki Ezawa, Toshiki Oonaka, Sadayoshi Furusawa, Shingo Nomura, Takashi Iihara