Patents Assigned to Hirai Kosaku Kabushiki Kaisha
  • Patent number: 5980179
    Abstract: An improved screw washer, and an improved mold for fabricating the improved screw washer. Using a selected metal plate having a thickness thinner than a nominal height demanded for a nut, the invention primarily aims to form an improved screw washer incorporating a nut satisfying the demanded height. The invention is to provide an improved screw washer, and an improved mold for fabricating the screw washer. Particularly, using this improved mold, the improved screw washer can easily be manufactured, where the above-identified nut is solidly bonded with the metal plate without being disengageable therefrom, and yet, a sufficiently lengthy tapped hole is formed. Structurally, a nut is formed in the state of being continuous to a metal plate after punching out part of the metal plate.
    Type: Grant
    Filed: March 16, 1998
    Date of Patent: November 9, 1999
    Assignee: Hirai Kosaku Kabushiki Kaisha
    Inventor: Takashi Hirai
  • Patent number: 5755133
    Abstract: An improved screw washer, and an improved mold for fabricating the improved screw washer. Using a selected metal plate having a thickness thinner than a nominal height demanded for a nut, the invention primarily aims to form an improved screw washer incorporating a nut satisfying the demanded height. The invention is to provide an improved screw washer, and an improved mold for fabricating the screw washer. Particularly, using this improved mold, the improved screw washer can easily be manufactured, where the above-identified nut is solidly bonded with the metal plate without being disengageable therefrom, and yet, a sufficiently lengthy tapped hole is formed. Structurally, a nut is formed in the state of being continuous to a metal plate after punching out part of the metal plate.
    Type: Grant
    Filed: November 18, 1996
    Date of Patent: May 26, 1998
    Assignee: Hirai Kosaku Kabushiki Kaisha
    Inventor: Takashi Hirai
  • Patent number: 5626521
    Abstract: A method of manufacturing an improved screw washer, an improved screw washer, and an improved mold for fabricating the improved screw washer. Using a selected metal plate having a thickness thinner than a nominal height demanded for a nut, the invention primarily aims to form an improved screw washer incorporating a nut satisfying the demanded height. The invention is to provide an improved method of manufacturing an improved screw washer, the improved screw washer, and an improved mold for fabricating the screw washer. Particularly, using this improved mold, the improved screw washer can easily be manufactured, where the above-identified nut is solidly bonded with the metal plate without being disengaged therefrom, and yet, a sufficiently lengthy tapped hole is formed. Structurally, a nut is formed in the state being continuous to a metal plate after punching out part of the metal plate.
    Type: Grant
    Filed: September 1, 1993
    Date of Patent: May 6, 1997
    Assignee: Hirai Kosaku Kabushiki Kaisha
    Inventor: Takashi Hirai