Patents by Inventor Malcolm Duncan

Malcolm Duncan 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: 5848715
    Abstract: A roll bar and crane device for use with vehicles such as a truck is adapted to be mounted to the truck bed. The device includes left and right leg members and a central beam extending therebetween and being selectively detachable thereto. A U-shaped boom extends over the left and right leg members when used as a roll bar. The boom, at one end, is pivotally connected to a pivot member about a horizontal axis of rotation and the pivot member is pivotally connected to one of the leg members and is pivotable about a vertical axis of rotation. A hydraulic jack selectively lifts and lowers the boom when used as a crane. Covers are provided on the boom left and right legs and hide from plain view working components including the hydraulic jack.
    Type: Grant
    Filed: November 1, 1996
    Date of Patent: December 15, 1998
    Inventor: Malcolm Duncan
  • Patent number: 5730304
    Abstract: A roll bar and crane device for use with vehicles such as a truck is adapted to be mounted to the truck bed. The device includes left and right leg members and a central beam extending therebetween and being selectively detachable thereto. A U-shaped boom extends over the left and right leg members when used as a roll bar. The boom, at one end, is pivotally connected to a pivot member about a horizontal axis of rotation and the pivot member is pivotally connected to one of the leg members and is pivotable about a vertical axis of rotation. A rope and pulley system is provided between the pivot member and the boom. A rope extends from the boom lift end to the pulley and rope system and to a winch that is located on and is rotatable with the pivot member. By pulling the rope via the winch, objects attached to the end of the rope are drawn up and to the boom lift end and the boom is also caused to pivot about the horizontal axis of rotation for lifting the boom lift end.
    Type: Grant
    Filed: November 12, 1996
    Date of Patent: March 24, 1998
    Inventor: Malcolm Duncan
  • Patent number: 5089676
    Abstract: A liquid level detector for detecting liquid level height in a vessel includes a housing adapted to float in the liquid, first and second spaced, fixed stops disposed in the housing, a pendulum having a end pivotally mounted in the housing wherein the pendulum is movable between the stops in response to a change in orientation of the housing due to a change in liquid level height in the vessel, an electrical switch disposed of in the housing adjacent to the first stop and actuable by the pendulum and a cable for tethering an end of the housing to the vessel.
    Type: Grant
    Filed: May 16, 1990
    Date of Patent: February 18, 1992
    Assignee: Magnetrol International Incorporated
    Inventor: Malcolm Duncan
  • Patent number: 4917135
    Abstract: A liquid regulator device has a buoyant body which is anchored to a side of the vessel by an electrical conductor. The body contains a movable ballast in the form of a ball and an attitude sensitive switch connected to the electrical conductor. The buoyant body floats in the liquid with one end in the uppermost position. Changing the liquid level tensions the electrical conductor causing the body to tumble. When the body has tumbled through a predetermined angle, the ballast moves from one end of the body to the other to cause the body to rapidly assume the reverse orientation. This causes the attitude sensitive switch to change state, which is used to control the liquid level.
    Type: Grant
    Filed: February 23, 1989
    Date of Patent: April 17, 1990
    Assignee: Magnetrol International
    Inventor: Malcolm Duncan
  • Patent number: D399476
    Type: Grant
    Filed: November 1, 1996
    Date of Patent: October 13, 1998
    Inventor: Malcolm Duncan