US Patent 7556468 Folding wheel retainer for wheel lift system

A wheel lift system for use with a transporter vehicle is provided. The wheel lift system comprises a boom assembly, a cross bar supported at a distal end of the boom assembly, a first arm supported at the cross bar and configured to move between a stowed position and a use position, and a second arm movably coupled to the first arm and configured to move between a stowed position and a use position. A cam is provided for moving the second arm from the use position to the stowed position. The wheel lift system may optionally include an unfolding mechanism for moving the second arm from the stowed position to the use position.