US Patent 7641011 Pallet jack having width-adjustable fork prongs

A pallet jack includes a frame and a pair of outwardly projecting load prongs connected to the frame. The proximal ends of the prongs are connected to a horizontal member on the rear of the frame by brackets that keep the prongs out of the frame proper. A threaded rod is mounted horizontally on the horizontal member and is threaded into the proximal end of each prong, with the two ends of the threaded rod having opposite hand threads. The threaded rod is rotated by a user turning a crank mounted on top of the frame and connected to the adjustment threaded rod by a chain drive, allowing the width between the prongs to be adjusted inwardly or outwardly.