Patent ID: 8851238

Claim:
An apparatus comprising: a winch member; a winch motor adapted to rotate the winch member in a first direction to wrap a portion of a cable about the winch member to raise a lifting platform assembly and to rotate the winch member in an opposing second direction to unwrap said portion of the cable from the winch member to lower the lifting platform assembly; and a tension detection switch assembly comprising a switch connected to the winch motor and a biasing member which exerts a bias force upon the winch member to nominally deflect the winch member to a first position which sets the switch to deactivate the winch motor in an absence of tension in the cable from the lifting platform assembly, wherein a presence of tension in the cable from the lifting platform assembly deflects the winch member to a second position which sets the switch to activate the winch motor, wherein the biasing member supports a selected end of the winch member relative to a winch housing, and wherein the presence of tension in the cable deflects the selected end of the winch member away from the winch housing and the absence of tension in the cable facilitates retraction of the selected end of the winch member by the biasing member toward the winch housing.