GB532980A - Improvements relating to hydraulic intensifiers - Google Patents

Abstract

532,980. Hydraulic intensifiers. E.M.B. CO., Ltd., and SMITH, S. Sept. 28, 1939, No. 26801. [Class 69 (ii)] A hydraulic intensifier of the kind actuated by compressed air and which is especially applicable for use in connection with riveting &c. machines comprises a cylinder a, in which works the piston f operated by compressed air against the action of a spring g, and coaxial with the cylinder a are a low power hydraulic cylinder b and a high power cylinder c which is connected by a pipe 3 to the cylinder 4 of the riveting &c. press. A rod h attached to the piston f is connected to a piston k in the low pressure cylinder, and to a piston j which moves in the high pressure cylinder c. On the initial descent of the piston f the liquid forced by the piston k can pass through a non-return valve n into the chamber c, and there is a big outflow of liquid at low pressure through the chamber c. When the load is applied to piston 5 the valve n closes under the high pressure in chamber c. During this movement the liquid can pass from chamber b through a relief valve u controlling passages o in the piston k into a relief chamber d. On the reverse movement the liquid flows back into the chamber b from the chamber d through passages controlled by a valve 2. In a modification the lower end of chamber b is connected directly to the top of cylinder 4 through a non-return valve in a conduit which is joined by the outlet of chamber c at a point beyond this valve. A throttle adjustable by a screw controls the flow of liquid from the high power cylinder c, and this screw throttle is byepassed by a pipe which permits a ready return of the liquid through a non-return valve.