When piston 1 moves to the right by the action of liquid delivered to the left end of the cylinder, rocker arm 2, whose rounded ends enter slots in clamping bolts 3, moves the bolts and V-block 6, clamping workpiece 5 against locating surface a. Workpiece 5 is released when piston 1 is moved to the left by spring 4.
$3861$LHP,GC$