Pilot hydraulic system for operating control valve
AssigneeR.F.G. Trading Ltd.
InventorBenyamin Aharoni
Life of this patent
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Abstract
A pilot valve system is controlled by the pressure differential between a lower chamber and an upper chamber. A fluid passageway in the lower chamber fluidly connects an inlet to first and second outlets. By varying the pressure differential, the placement of a stem within the fluid passageway is varied so fluid can flow between the inlet and only one of the first and second outlets at a time. Pressure in the lower chamber can be varied by using a second fluid to exert pressure against a bottom end of the stem. Pressure in the upper chamber is varied by using an adjusting screw to urge a spring against the diaphragm.
Claims18
A poppet-free pilot valve system, comprising:
- a lower chamber formed from:
- a pilot body having a fluid passageway defined therein, the fluid passageway connecting an inlet to a first outlet and a second outlet;
- and
- a stem in the fluid passageway adapted to permit fluid to flow between the inlet and only one of the first and second outlets at a time;
- and
- an upper chamber separated from the lower chamber by a diaphragm, the upper chamber including:
- a compression spring;
- and
- an adjusting screw for controlling the amount of force provided by the compression spring against the diaphragm.
A method of delivering fluid from a first inlet to only one of a first outlet and a second outlet using a pilot valve system, comprising:
- providing a pilot valve system comprising:
- a lower chamber formed from:
- a pilot body having a fluid passageway defined therein, the fluid passageway connecting an inlet to a first outlet and a second outlet;
- and
- a stem in the fluid passageway adapted to permit fluid to flow between the inlet and only one of the first and second outlets at a time;
- and
- an upper chamber separated from the lower chamber by a diaphragm, the upper chamber including:
- a compression spring;
- and
- an adjusting screw for controlling the amount of force provided by the compression spring against the diaphragm;
- flowing a first fluid through the inlet;
- and
- flowing a second fluid through an opening at a bottom end of the lower chamber to control a placement of the stem within the fluid passageway and determining whether fluid flows to the first outlet or the second outlet.
Dependencies are inferred from the claim text.