Patents by Inventor Yasushi Tokumo

Yasushi Tokumo 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: 7112976
    Abstract: Two resilient sections are connected to a tip end which is to be brought into contact with an external connection terminal of a contact belonging to a test socket of an electronic device or semiconductor package. The resilient sections provided opposite to each other and are bent so as to extend horizontally with respect to the tip end. The force exerted downward on the tip end is equally distributed between the plurality of resilient sections. The resilient sections are eventually deflected downwardly without involvement of horizontal sliding action. The force which is exerted on the tip end in reaction to the downward deflection of the curved portions brings the tip end into pressing contact with the external connection terminal without involvement of horizontal sliding action of the tip end with respect to the external connection terminal.
    Type: Grant
    Filed: May 11, 2004
    Date of Patent: September 26, 2006
    Assignee: Misubishi Denki Kabushiki Kaisha
    Inventors: Yasushi Tokumo, Shigeki Maekawa, Yoshihiro Kashiba, Shigeru Takada
  • Publication number: 20040209491
    Abstract: Two resilient sections are connected to a tip end which is to be brought into contact with an external connection terminal of a contact belonging to a test socket of an electronic device or semiconductor package. The resilient sections provided opposite to each other and are bent so as to extend horizontally with respect to the tip end. The force exerted downward on the tip end is equally distributed between the plurality of resilient sections. The resilient sections are eventually deflected downwardly without involvement of horizontal sliding action. The force which is exerted on the tip end in reaction to the downward deflection of the curved portions brings the tip end into pressing contact with the external connection terminal without involvement of horizontal sliding action of the tip end with respect to the external connection terminal.
    Type: Application
    Filed: May 11, 2004
    Publication date: October 21, 2004
    Applicant: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yasushi Tokumo, Shigeki Maekawa, Yoshihiro Kashiba, Shigeru Takada
  • Patent number: 6794890
    Abstract: Two resilient sections are connected to a tip end which is to be brought into contact with an external connection terminal of a contact belonging to a test socket of an electronic device or semiconductor package. The resilient sections provided opposite to each other and are bent so as to extend horizontally with respect to the tip end. The force exerted downward on the tip end is equally distributed between the plurality of resilient sections. The resilient sections are eventually deflected downwardly without involvement of horizontal sliding action. The force which is exerted on the tip end in reaction to the downward deflection of the curved portions brings the tip end into pressing contact with the external connection terminal without involvement of horizontal sliding action of the tip end with respect to the external connection terminal.
    Type: Grant
    Filed: July 24, 2000
    Date of Patent: September 21, 2004
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yasushi Tokumo, Shigeki Maekawa, Yoshihiro Kashiba, Shigeru Takada
  • Patent number: 6344753
    Abstract: On each of the contact terminals of a test socket, one or more contact projections having a radius of curvature within a specified range, such as 0.03 to 0.3 mm, are formed in the portion of the contact terminals which contacts the corresponding external connection terminal of an electronic device. Further, a plurality of protuberances and recesses are formed on the surface of the contact projection, and each of the protuberances is formed to assume a substantially spherical surface having a radius of curvature of 2 to 15 microns. The test socket is for use in testing an electrical characteristics of an electronic device or a semiconductor package, and stable electrical contact is ensured between contact terminals of the test socket and external connection terminals of an electronic device or a semiconductor package.
    Type: Grant
    Filed: January 11, 2000
    Date of Patent: February 5, 2002
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Shigeru Takada, Yasushi Tokumo, Shigeki Maekawa, Keiko Kaneko