Patents by Inventor Hin Ming Lam

Hin Ming Lam 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
  • Patent number: 6590175
    Abstract: An electrical switch, such as a rocker switch, includes a casing, three fixed contacts, each contact having an inner end, and an operating rocker movable between an operating position and a non-operating position. The switch includes a moving contact movable by the rocker to make and break electrical connection between the inner ends of a first pair of the fixed contacts (connectable to a load and a power source) while the rocker is in the operating and non-operating positions, respectively. Also included are a light bulb, lighting to indicate when the rocker is in the operating position, and an associated resistor. The light bulb and resistor are connectable in series across the inner ends of a second pair of the fixed contacts (connectable to a power source) when the rocker is in the operating position. The resistor is fixed, has a body, and has first and second terminals.
    Type: Grant
    Filed: June 3, 2002
    Date of Patent: July 8, 2003
    Assignee: Defond Manufacturing Limited
    Inventor: Hin Ming Lam