Throttle valve

Claim 2

A throttle valve for controlling a pressurized fluid comprising a housing having a bore; a pair of axially spaced spool members slidably mounted within said bore; means for unitarily moving said spool members in said housing and maintaining their spaced relationship; said housing having an inlet line and an outlet line axially spaced from each other and in fluid communication with said bore; means disposed in said housing providing axially spaced apertures of graduated size located in the path of fluid flowing through said valve from said inlet line to said outlet line; said spool members being axially movable to open and closed positions whereby to respectively uncover or cover all of said apertures; one of said spool members having an axial length at least equal to the distance covered by said apertures adapted to progressively cover said apertures and maintain said apertures covered during movement to closed position to control the flow of fluid through said valve and contain the fluid between said spool members; said spools being spaced apart a sufficient distance to cause said inlet line to be disposed between said spools in any position of said spools whereby pressure fluid trapped between said spools exerts equal pressure in both axial directions at all times to stabilize said valve in any position of said spools.

Claim 3

A throttle valve as set forth in claim 1 wherein the sizes of said apertures progressively increase in one axial direction whereby when said one spool moves toward the closing position, the largest apertures will be covered first to afford means to effect a rapid shutoff of fluid flow.

Claim 4

A throttle valve for controlling a pressurized fluid comprising a housing having a cylindrical bore; a sleeve closely interfitting inside said bore; a plurality of apertures in said sleeve spaced in the axial direction; means defining a recess in the surface of said bore connecting all of said apertures; means providing inlet and outlet fluid passages, said inlet passage extending through said housing and said sleeve at a point axially spaced from said apertures, and said outlet passage intersecting said recess; a pair of axially slidable spool members carried coaxially by a piston rod within said sleeve, said spool members being axially movable to open and closed positions whereby to respectively uncover or cover all of said apertures; one of said spool members being of a length at least equal to the axial distance covered by said apertures and adapted to progressively cover said apertures and maintain said apertures covered during movement to closed position to control the fluid flow and contain the fluid between said spool members; the other of said spool members being spaced axially fron said one spool member a sufficient distance to cause said inlet passage to be disposed between said spools in any position of said throttle valve whereby pressurized fluid is trapped between the two spools and exerts equal pressure in both axial directions at all times to stabilize said valve and prevent fluid pressure from forcing said valve to the open position.

Claim 5

A throttle valve for controlling a pressurized fluid comprising a housing having a cylindrical bore; a sleeve closely interfitting inside said bore; a plurality of apertures in said sleeve spaced in the axial direction; means defining a recess in the surface of said bore connecting all of said apertures; means providing inlet and outlet fluid passages, said inlet passage extending through said housing and said sleeve at a point axially spaced from said apertures, and said outlet passage intersecting said recess; a pair of axially slidable spool members carried coaxially by a piston rod within said sleeve, said spool members being axially movable to open and closed positions whereby to respectively uncover or cover all of said apertures; one of said spool members being of a length at least equal to the axial distance covered by said apertures and adapted to progressively cover said apertures and maintain said apertures covered during movement to closed position to control the fluid flow and contain the fluid between said spool members; the other of said spool members being spaced axially fron said one spool member a sufficient distance to cause said inlet passage to be disposed between said spools in any position of said throttle valve whereby pressurized fluid is trapped between the two spools and exerts equal pressure in both axial directions at all times to stabilize said valve and prevent fluid pressure from forcing said valve to the open position.

Claim 6

A throttle valve as set forth in claim 3 wherein the sizes of said apertures progressively increase in one axial direction whereby when said one spool moves toward the closing position, the largest apertures will be covered first to effect a rapid reduction in fluid flow and whereby when said one spool moves from closed to open position, only the smallest apertures are initially uncovered to effect a smooth delivery of fluid power.

Claim 7

A throttle valve as set forth in claim 3 wherein said housing includes end plates secured to said housing and substantially closing the ends of said bore; said end plates having relief apertures therein to exhaust fluid trapped between said spool members and said end plates; one of said end plates affording an opening for said piston rod to project outwardly of said housing.

Claim 8

A throttle valve as set forth in claim 1 wherein said housing includes end plates secured to said housing and substantially closing the ends of said bore; one of said end plates affording an opening for said piston rod to project outwardly of said housing; said housing having drain apertures in the bottom thereof adjacent to the ends of said bore which comprise relief apertures for exhausting gaseous fluid trapped between said spool members and said end plates and as drain holes for draining of liquid fluids.

Claim 9

A throttle valve for controlling a pressurized fluid comprising a housing having a cylindrical inner surface; a sleeve having a cylindrical outer surface closely interfitting inside said housing; a plurality of apertures in said sleeve spaced in the axial direction; means defining a recess in one of said surfaces connecting all of said apertures; means providing inlet and outlet fluid passages, said inlet passage extending through said housing and said sleeve at a point axially spaced from said apertures, said outlet passage intersecting said recess; a pair of axially spaced spool members slidably mounted within said housing; said spool members being axially movable to open and closed positions whereby to respectively uncover or cover all of said apertures; means for unitarily moving said spool members in said housing and maintaining their spaced relationship, one of said spool members being of a length at least equal to the axial distance covered by said apertures and adapted to progressively cover said apertures and maintain said apertures covered during movement to closed position to control the fluid flow and contain the fluid between said spool members; the other of said spool members being spaced axially from said one spool member a sufficient distance to cause said inlet passage to be disposed between said spools in any position of said throttle valve whereby pressurized fluid is trapped between the two spools and exerts equal pressure in both axial directions at all times to stabilize said valve and prevent fluid pressure from forcing said valve to the open position.

Claim 10

A throttle valve for controlling a pressurized fluid comprising a housing having a cylindrical inner surface; a sleeve having a cylindrical outer surface closely interfitting inside said housing; a plurality of apertures in said sleeve spaced in the axial direction; means defining a recess in one of said surfaces connecting all of said apertures; means providing inlet and outlet fluid passages, said inlet passage extending through said housing and said sleeve at a point axially spaced from said apertures, said outlet passage intersecting said recess; a pair of axially spaced spool members slidably mounted within said housing; said spool members being axially movable to open and closed positions whereby to respectively uncover or cover all of said apertures; means for unitarily moving said spool members in said housing and maintaining their spaced relationship, one of said spool members being of a length at least equal to the axial distance covered by said apertures and adapted to progressively cover said apertures and maintain said apertures covered during movement to closed position to control the fluid flow and contain the fluid between said spool members; the other of said spool members being spaced axially from said one spool member a sufficient distance to cause said inlet passage to be disposed between said spools in any position of said throttle valve whereby pressurized fluid is trapped between the two spools and exerts equal pressure in both axial directions at all times to stabilize said valve and prevent fluid pressure from forcing said valve to the open position.