Ram locking unit for metal forming press - has tie bolt head and shank in form of single acting hydraulic cylinder and piston rod, working chamber is connected to two=way valve with accumulator

摘要

A tie bolt (13) is fastened in the end of a leadscrew (9) which passes through an axially fixed nut (7) and can be raised or lowered by a motor (12) driving onto the nut. The leadscrew can also be turned through 90 deg. by a second motor drive (11) to bring the tie bolt head (14) into engagement with an aperture in the press ram. The tie bolt head and tie bolt shank are in the form of a single-acting hydraulic cylinder and piston rod. The upper working chamber (18) is connected to a two-way valve (23) which in turn is connected to an accumulator. ADVANTAGE - Greater ease and convenience of unlocking ram.