APPARATUS FOR OPTIONALLY SELECTING THE THRUST FORCE IN FRICTION WELDING

摘要

An improved apparatus for optionally selecting one of a plurality of thrust forces required for generating heat by the frictional contact between two workpieces for performing the upset operation during a friction welding operation. Two series of thrust force generating systems are combined in a hydraulic circuit which is connected to three hydraulic cylinders of the friction welder. One of the hydraulic cylinders is secured to a bed of the friction welder at an outside position of a slide table while the other two hydraulic cylinders are disposed at the counter side positions with respect to the slide table. In a typical embodiment, one of the thrust force generating systems is preferably applied for generating the thrust force which is required for operating the upset operation while the other one is applied for generating the thrust force which is required for generating heat. The above-mentioned combination of the thrust forces is optionally selected by operating means for selecting the system which comprises a plurality of solenoid selector valves, pressure reducing valves and their associated connections.