GB191518123A - Improvements in and relating to Fluid Pressure Regulating Valves. - Google Patents

Abstract

18,123. Auld, J., and Graham, J. Dec. 29. Pressure regulating valves.-A pressure-regulating or surplus-pressure valve, of the type actuated by a piston under the control of a diaphragm-actuated balanced auxiliary valve, has the supply duct to the auxiliary valve protected by a dirt trap fitted with a gauge screen, and has the auxiliary-valve casing arranged below the mainvalve casing. In the form shown in Fig. 1, the main valve 3 is connected to a leaky actuating- piston 6 by a spindle 5, having a reduced extension 9 adapted to engage a guide-socket on the cover 11. The auxiliary valve 25<a> has balancing-pistons 23, 30, and is actuated to control the admission inlet pressure beneath the piston 6, by outlet pressure admitted through a duct 22 and acting on a diaphragm 33 backed by a piston 32, against the action of a spring 37 actuating through a lever 39. The undue movement of the lever is prevented by an adjustable stop 40. The duct 17<a> leading to the auxiliary valve is covered by a gauze screen 18 depending into a dirt pocket 20 provided with suitable clearing-means. A modification isdescribed in which the ducts leading to the auxiliary valve are reversed to enable the main valve to act as a surplus-pressure valve. In a further modification, the two arrangements of auxiliary valve are used to control a single main valve.