Workpiece 4 is mounted on two locating pins 2. One pin has a cylindrical locating surface and the other a diamond-shaped surface with the larger axis of the diamond pin perpendicular to the line of centres through the pins. A diamond locating pin is required so that the workpiece can be readily mounted on the pins even with deviations in the centre-to-centre distance between its holes. Rocker arm 3, connected by turning pair A to the rod of piston 1, has rounded ends fitting into slots in pins 2. When piston 1 moves to the right by the action of fluid delivered to the left end of its cylinder, workpiece 4 is clamped against the end face of housing 6 biy slotted strap 7 that engages the heads of locating pins 2. As piston 1 is moved to the left by spring 5, workpiece 4 is released and, after removing strap 7, can be taken off pins 2.
$3856$LHP,GC$