Patents by Inventor Tzung-Yen Yang

Tzung-Yen Yang 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: 6386074
    Abstract: An articulated screwdriver has a handle and a shank secured on the handle. The shank has a ball-end formed at a free end thereof, and an outer thread formed on an outer periphery close to the free end. A joint sleeve has a joint formed at a first end thereof and an opening defined at a second end. The ball-end is pivotally mounted in the opening. A positioning sleeve screwed on the shank has an inner thread engaged with the outer thread. Whereby, when the positioning sleeve is moved forwards to enter the opening, the shank is unable to be pivoted about the joint sleeve and when the positioning sleeve is distant from the opening the joint sleeve is able to pivot relative to the shank.
    Type: Grant
    Filed: May 4, 2001
    Date of Patent: May 14, 2002
    Inventor: Tzung-Yen Yang