HYDROPHEUMATIC ARRANGEMENT FOR PROTECTING MECHANICAL PRESS AGAINST OVERLOADS Russian patent published in 1994 - IPC

FIELD: mechanical engineering. SUBSTANCE: arrangement has hydraulic valve with movable element mounted so as to close discharge line, and air cylinder. The movable element with gate has the form of flat valves with rod and pushers. Arrangement further has ball locking member with annular groove at side surface of air cylinder and balls located between pusher and piston of air cylinder adapted to engage with annular groove. In response to an increase in pressure of working fluid the force transmitted through pusher and balls to the piston exceeding the force produced by the pressure of compressed air exerted thereon the piston retracts and balls roll out of the grooves to free the pusher. In this position of parts of ball lock member the force of resistance to opening the hydraulic valve is reduced, valves open discharge line, and working fluid escapes to prevent overloading. EFFECT: higher reliability of protection. 4 dwg