GB443165A - Improvements in hydraulic valves - Google Patents

Abstract

443,165. Hydraulic presses &c. TAYLOR, A. W., 5, New Brown Street, Manchester, and BOLTON, E. A., Cale Green House, Cale Green, Stockport. Sept. 14, 1934, No. 26376. [Class 69 (ii)] An arrangement of valves, for controlling the supply of low and high pressure water to hydraulic presses &c., of the type in which the high pressure inlet valve is automatically opened and the low pressure inlet valve automatically closed when the low pressure supply has exerted its maximum effect, comprises a casing provided with a high pressure inlet valve c, a low pressure inlet valve b, a control valve F and an exhaust valve G. When the valve F is opened, low pressure water entering at B lifts the valve b against spring action and passes through a passage A and port D to the press. The pressure in the passage A obtains access through a passage f<5> in the valve F and a port m to the underside of a piston c<2> on the spindle of the valve c adjustably loaded by a spring c<3>; when this pressure becomes equal to that of the low pressure supply, the valve c is lifted to admit high pressure liquid which passes to the press and closes the low pressure inlet valve b. When the exhaust valve G is opened, and the valve F closed, the valve c is reclosed by the spring c<2> and the pressure action on a piston c<1>. The exhaust valve G has a pilot valve g<2>, the valve F is held on its seat by a spring f<4> and pressure on a piston f and the high pressure inlet C may be connected to sources at different pressures.