Hydraulic cylinder-piston unit provided with a mechanical safety device, particularly for pantograph type motor vehicle lifts

摘要

A hydraulic jack particularly intended for use in automobile lifts includes a safety stop mechanism including a fixed toothed rod and a piston-supported pawl mechanism which includes one or more stop members. Each of the stop members can be retracted, to allow the jack to collapse, by applying hydraulic pressure to the chamber above the piston.