Abstract: A combined fluid pressure reducing and relief valve having aligned inlet and outlet connections, a pair of abutting rotary disc valve sets each having an inboard stationary and an outboard rotary ceramic disc which are relatively rotatable against each other to expose and close openings therein. The sets are regulated by a pressure sensitive member comprising a diaphragm flush with a piston which is movable against a spring in response to low pressure fluid in the valve whereby one set opens until that pressure reaches a “set” pressure. If the low pressure increases to a “initial relief pressure,” further movement of the pressure sensitive member results. Finally with still further movement the low pressure side reaches a “relief pressure” whereby the other rotary valve set opens while the first is closed and remains open until the low pressure side is reduced to below the “set” pressure.

Abstract: According to one aspect of the present invention there is provided a valve assembly which includes: at least one valve port; at least one fluid inlet; and an outlet for connection to a fluid system; characterised in that the valve assembly includes a pressure sensitive member which is connected to the outlet, so that the size of the pressure sensitive member is capable of increasing or decreasing. In response to pressure changes within the fluid system, wherein the valve is configured so that said increases or decreases to the size of the pressure sensitive member cause the inlet and valve port to move either into or out of alignment with one another.