Flow control valve

Claim 2

A flow control valve comprising: a housing having a bore with an inlet for connection to a source of pressurized fluid and a controlled flow outlet; a control member slidably disposed in said bore, said control member cooperating with said outlet and having an axial groove for defining a flow control orifice between said inlet and said outlet, the area of said orifice being linearly proportional to the axial position of said control member, in all operable positions of said control member; said groove being of a constant width with the bottom thereof being radially inwardly inclined at a constant rate of inclination with respect to the axis of said control member, the bottom of said groove having the same curvature and extending in the same direction as the interior surface of said bore; control means for axially positioning said control member in response to a preselected variable parameter; and pressure compensating means for maintaining a substantially constant pressure drop across said flow control orifice and maintaining flow linearly proportional to the position of said control member.

Claim 3

A flow control valve comprising: a housing having a cylindrical cross-sectional bore therein, said bore having an inlet for connection to a source of pressurized fluid and a radial outlet for connection to a fluid operated device, said radial outlet partially defined by a circumferential edge towards said inlet; and a control member for controlling the flow of fluid between said inlet and said outlet, said control member comprising a circumferential surface sealingly engaged in said bore and an end surface communicating with said inlet, said control member having an axially extending constant width groove defined by two parallel side walls and a curved bottom which iS inclined radially inwardly from the circumferential surface at a constant rate of inclination with respect to the axis of the control member, the contoured bottom having the same curvature and extending in the same direction as the interior of said bore, said control member axially movable towards said outlet to selectively register said groove with said outlet defining a flow control orifice therebetween, the area of said orifice being linearly proportional to the axial position of said control member.

Claim 4

A flow control valve comprising: a housing having a cylindrical cross-sectional bore therein, said bore having an inlet for connection to a source of pressurized fluid and a radial outlet for connection to a fluid operated device, said radial outlet partially defined by a circumferential edge towards said inlet; and a control member for controlling the flow of fluid between said inlet and said outlet, said control member comprising a circumferential surface sealingly engaged in said bore and an end surface communicating with said inlet, said control member having an axially extending constant width groove defined by two parallel side walls and a curved bottom which iS inclined radially inwardly from the circumferential surface at a constant rate of inclination with respect to the axis of the control member, the contoured bottom having the same curvature and extending in the same direction as the interior of said bore, said control member axially movable towards said outlet to selectively register said groove with said outlet defining a flow control orifice therebetween, the area of said orifice being linearly proportional to the axial position of said control member.

Claim 5

The flow control valve of claim 2 wherein said control member has a plurality of axially extending grooves equally circumferentially spaced about its circumference.

Claim 6

A spool for a flow control valve, said spool having an outer surface with a radius of curvature and an axial groove therein, said groove forming a flow control orifice, which orifice varies linearly with all positions of said spool, said groove having parallel side walls with the bottom thereof inclined to the axis of said spool and having the bottom in transverse section of the same radius of curvature and extending in the same direction as the outer periphery of said spool.

Claim 7

A spool for a flow control valve, said spool having an outer surface with a radius of curvature and an axial groove therein, said groove forming a flow control orifice, which orifice varies linearly with all positions of said spool, said groove having parallel side walls with the bottom thereof inclined to the axis of said spool and having the bottom in transverse section of the same radius of curvature and extending in the same direction as the outer periphery of said spool.