Overload safeguard system for press - has pressure cushion in hydraulic fluid circuit reacting on counter-pressure system

摘要

A pressure cushion (2) is mounted on the end of a ram (1). The cushion can be filled with a pressurised liquid via a non-return valve (6). A main valve body (7) contains a main valve with piston (14) and an auxiliary valve with piston (15). A counter pressure system loads the pistons of the valves in the closed position. Excess pressure in the cushion lifts the piston of the auxiliary valve which releases the pressure of the counter pressure system on the piston of the main valve. The area (9) above the auxiliary valve is directly connected to the pressure cushion.