Patents by Inventor Ka Fai Lai

Ka Fai Lai 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: 7210542
    Abstract: A safety device for a power tool having an electric motor and a trigger to activate the motor via a primary trigger-activated switch, includes an auxiliary switch in circuit with the motor, an activator movable between a first position in which the auxiliary switch is opened by the activator and the activator prevents depression of the trigger, and a second position in which the auxiliary switch is closed by the activator and the activator allows depression of the trigger.
    Type: Grant
    Filed: September 23, 2004
    Date of Patent: May 1, 2007
    Assignee: Defond Components Limited
    Inventors: Hin Ming Lam, Ka Fai Lai, Ting Yu Kwan
  • Publication number: 20050173236
    Abstract: An electrical switch includes a casing having a central and two side chambers that are separated from the central chamber by respective partitions. A switching mechanism in each second chamber has fixed and moving contacts and an actuator. A rocker in the central chamber is used to cause the actuators to move the moving contacts into contact with and out of contact from the fixed contacts. There is also included engaging means engaging each actuator to the rocker for movement thereby, which has a circular part that extends across the first and second chambers rotatably snugly through a circular hole in the partition such that partitioning between the central and side chambers is substantially splash, jet or dust proof.
    Type: Application
    Filed: February 6, 2004
    Publication date: August 11, 2005
    Applicant: Defond Components Limited
    Inventor: Ka Fai Lai
  • Patent number: 6919523
    Abstract: An electrical switch includes a casing having a central and two side chambers that are separated from the central chamber by respective partitions. A switching mechanism in each second chamber has fixed and moving contacts and an actuator. A rocker in the central chamber is used to cause the actuators to move the moving contacts into contact with and out of contact from the fixed contacts. There is also included engaging means engaging each actuator to the rocker for movement thereby, which has a circular part that extends across the first and second chambers rotatably snugly through a circular hole in the partition such that partitioning between the central and side chambers is substantially splash, jet or dust proof.
    Type: Grant
    Filed: February 6, 2004
    Date of Patent: July 19, 2005
    Assignee: Defond Components Limited
    Inventor: Ka Fai Lai