Ram-operated pincers with adjustable grip pressure - use return sprung two-way ram pincer motor fed through piston rod bore of main two way ram

摘要

The servo pincers use a pair (1,23) of coupled two way hydraulic rams. The main ram (1) has a cylinder (2) which is divided into fore (7) and aft (6) chambers by a piston block (5), being connected to the circuit (57-60) by wall apertures (11,12) at each cylinder end. A hollow piston rod (8) extends from the front piston (5) face to pass through an annular sealed cap (14). A pincer carrying head (21) incorporates the secondary ram (22) whose return sprung piston (23) effects pincer arm (17,18) convergence. Gate valves (51-54) put the rams in circuit with either a fluid source or a reservoir, and the arrangement retards ram movement until the pincers grip a workpiece at a predetermined pressure.