GB1290107A - - Google Patents

Abstract

1290107 Machine tool details J J SENDOYKAS 1 April 1971 8421/71 Heading B3B [Also in Division F1] An hydraulic or pneumatic actuator piston 58, Fig. 1, is locked at the end of its outward stroke by three headed pins 136, 138, 140, Fig. 2, which after passing through the larger diameter ends of keyhole slots 142, 144, 146 in a locking ring 100 rotatable about the axis of the actuator cylinder 18 are urged outwardly by the cam action of a bevel (154), Fig. 7 (not shown), on the smaller diameter end of each slot 142, 144, 146 with the bevelled underside (158) of each pin 136, 138, 140 when locking ring 100 is rotated anticlockwise from the position shown in Fig. 2. Thus on removal of operating fluid pressure the piston remains urged against the cylinder end 24. Rotation of ring 100 to effect locking and unlocking of piston 58 is effected by linear movement of a fluid pressure operated plunger 104 which carries a slidable bearing block 130 journalled on a pivot 132 on and movable with the ring 100. The actuator may serve to operate a workpiece clamping bar 170, Fig. 9, pivoted at 172 to a V-shaped body 166 and pivoted at 178 to the outer end of the actuator rod 60; the locking end of the actuator cylinder 18 also being pivoted to the body 166 at 174. The actuator may serve to hold a machine tool slide (190), Fig. 11 (not shown), stationary.