Hand operated jack for vehicle trailer - incorporates safety mechanism to prevent uncontrolled rotation of the hand crank

摘要

The height-adjustable support is for an articulated trailer vehicle. It has two lifting jacks operated by a hand crank connected by a common shaft. A blocking mechanism (74) permits the rotation of the crankshafts (39,40) in both directions but blocks the rotation at the onset of torsional moments by means of a pin-slot connection (77,78). USE/ADVANTAGE - Safety system for a trailer jack which prevents the dangerous and uncontrolled backward rotation of the hand crank.