Automatic reciprocating way reciprocal moveable fluid pressure drive unit, the switching valve and drive for reciprocation

摘要

PURPOSE: To switch a fluid pressure drive unit by sensing the reduction of discharged fluid pressure at the end of movement of the fluid pressure drive unit in either direction of the reciprocation. ;CONSTITUTION: This invention relates to a method of reciprocating a piston 12 automatically in a cylinder 10 of a piston-cylinder unit, in which the piston 12 reciprocates alternately to the opposite sides of the cylinder 10 between the limits with a distance from each other with fluid pressure applied from a fluid pressure source 46, and at the same time, fluid pressure is let out from the side of the cylinder 10 in the moving direction of the piston 12. When the piston 12 reaches the limit of moving in one direction in the cylinder 10, the reduction of the discharged fluid pressure in the cylinder 10 is utilized for applying the fluid pressure to the side of the piston 12 which reverses the moving direction of the piston in the cylinder 10.;COPYRIGHT: (C)1996,JPO