Patents by Inventor Akio Tosa

Akio Tosa 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: 4417464
    Abstract: The present invention relates to a nib for a forming tool of bolt head or nut, wherein a nib 7 to be used for a tool comprises a segment combination nib 2 composed of a plurality of nib segments 1, and a regular polygonal hole 6 is formed at the inside of the nib. Regular polygon is formed also at the outside of the segment combination nib 2, and a bush 3 having the same shape as the nib 2 is fitted thereto so as to reinforce the nib 7. Moreover, stress absorbing hole 9 is formed on edge portion inner circumference of the bush 3 or outer surface of the segment combination nib 2. Since the stress absorbing hole 9 serves to absorb stress concentration applied to the nib segments 1, the nib 7 is not liable to flaw in comparison to prior art and stopping of the machine for exchange of the nib 7 is scarcely needed. Accordingly a forming tool with effect of improving the productivity can be provided.
    Type: Grant
    Filed: November 4, 1981
    Date of Patent: November 29, 1983
    Assignee: Mitsutoyo Kiko Co., Ltd.
    Inventor: Akio Tosa