Patent 6851523 was granted and assigned to LG on February, 2005 by the United States Patent and Trademark Office.
A horizontally extending body or base member includes a forward portion and a rearward portion and has downwardly projecting teeth for engaging a wire grid mounted on a bed or floor. The forward portion of the base member supports a wheel engaging head member for relative horizontal movement between extended and retracted positions, and compression springs bias the head member to its extended position. A lock member is supported by the rearward portion of the base member for pivotal movement between released and locked positions and also has downwardly projecting teeth for engaging the wire grid. The head member carries a wheel engaging extension member for pivotal movement between retracted and extended positions. A side paddle member is also carried by the head member to resist lateral movement of the wheel, and preferably all of the members are each molded of a liquid thermoset plastics material.