Patents by Inventor Kai Ching A. Yau

Kai Ching A. Yau 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).

  • Lighting device
    Patent number: 6227678
    Abstract: A lighting device includes a body having a compartment for containing a battery cell, a light bulb supported by the body for energization by the battery cell, a switch on the body for controlling the energization of the light bulb, and at least one contact unit at one end of the compartment for making co-axial contact withthe battery cell. The contact unit includes a conductive coil spring having an end, a conductive end cap at the end for contacting the battery cell, and a stationaryholder for maintaining the spring substantially straight.
    Type: Grant
    Filed: August 11, 1999
    Date of Patent: May 8, 2001
    Inventor: Andrew Kai Ching Yau
  • Lantern
    Patent number: D352565
    Type: Grant
    Filed: June 24, 1992
    Date of Patent: November 15, 1994
    Assignee: Practical Products Mfy. Ltd.
    Inventor: Kai Ching A. Yau