IMPROVEMENTS IN CONTROLS FOR VALVES

摘要

The invention relates to valves wherein the passageway therethrough is closed by a diaphragm and fluid pressure in the line in which the valve is located is used to close the valve. The valve is controlled by an auxiliary valve in a by-pass passage enabling the escape of fluid under pressure acting on the diaphragm to close the valve and a shaped member located in an aperture through the diaphragm such that there is co-ordination between the flow through the aperture and movement of the auxiliary valve.