Hydraulic force generator

摘要

The invention concerns a hydraulic force generator by means of pistons, in particular a transportable automobile jack. The object of the invention is to increase the pump's volume of delivery in no-load operation. This is achieved by arranging two pistons so that they can shift in an axial direction in one another, independently of one another; the inner piston has recesses on its outside and the outer piston on its inside that bear driving elements spring-mounted to push inwards or outwards.