Flow control valve

Abstract

In one embodiment, a constant-flow valve assembly is provided that comprises a first fluid passageway carrying fluid at a first fluid pressure, a piston chamber, and a second fluid passageway connected to the chamber and carrying fluid at the second fluid pressure. A third fluid passageway is configured to carry fluid at a third fluid pressure. An adjustable valve member is provided between the chamber and the third passageway to provide constant fluid flow to the third passageway. An adjustable restrictor assembly is positioned between the first and second fluid passageways. An inlet portion of the restrictor assembly receives fluid at the first fluid pressure and directs the fluid to a restrictor. An outlet portion receives fluid from the restrictor and directs the fluid to the second fluid passageway at the second fluid pressure. The restrictor is movable to adjust the position of entry and exit portions relative to the inlet and outlet portions to adjust a fluid flow rate through fluid pathway to the second fluid passageway, thereby adjusting the flow rate through the valve assembly.

1 . A constant-flow valve assembly, comprising:
 a body with a fluid inlet, a fluid outlet, a fluid passageway therebetween, and a piston chamber in fluid communication with the fluid passageway the fluid passageway containing fluid at first, second and third fluid pressures, wherein the third fluid pressure is less than the second fluid pressure, and the second fluid pressure is less than the first fluid pressure;   a piston slidably disposed in the piston chamber, a piston biasing member engaging the piston and having a piston biasing tension, and a biased valve assembly coupled to the fluid passageway and being configured to automatically adjust the piston biasing tension of the piston biasing member and a biased valve position in response to the first, second or third fluid pressures to provide a substantially constant fluid flow from the fluid outlet substantially independent of the pressure differentials between the second and third fluid pressures; and   a restrictor assembly with the fluid passageway extending therethrough, the restrictor assembly having a first sealing pad, a second sealing pad, and a restrictor with a fluid pathway extending therebetween, the first sealing pad being positioned to receive fluid at the first fluid pressure from a first portion of the fluid passageway and to direct the fluid to the restrictor, and the second sealing pad being positioned to receive fluid from the restrictor and direct fluid to a second portion of the fluid passageway at the second fluid pressure, the restrictor being movable to simultaneously adjust the piston biasing tension of the piston biasing member and to adjust the position of the fluid pathway relative to the inlet and outlet portions to adjust a fluid flow rate of fluid through fluid pathway to the second fluid passageway, thereby automatically adjusting the piston and the biased valve assembly to provide a substantially continuous flow rate through the valve assembly independent of the pressure differentials.   
     
     
         2 . The assembly of clam  1  wherein the restrictor has an outer surface, the fluid pathway includes the entry portion defined by at least one a blind notch in the outer surface and in fluid communication with a through hole, the restrictor being movable to allow the inlet portion to interfere with at least a portion of the entry portion to adjustably restrict the fluid flow into through the restrictor and to control the fluid flow rate through the adjustable restrictor assembly. 
     
     
         3 . The assembly of clam  1  wherein the restrictor has an outer surface, the fluid pathway includes the entry portion defined by a plurality of blind notches interconnected by at least one blind channel and in fluid communication with a through hole, the restrictor being movable to allow the inlet portion to interfere with at least a portion of the entry portion to adjustably restrict the fluid flow into the blind notches, blind channel, or through hole and to control the fluid flow rate through the adjustable restrictor assembly. 
     
     
         4 . The assembly of  claim 1  wherein the restrictor comprises a sleeve with an interior area and a central member disposed in the interior area, the fluid pathway extends through the sleeve and around the central member. 
     
     
         5 . The assembly of  claim 1 , further comprising an external adjustment device coupled to the restrictor assembly, the adjustment device being manipulatable to move the restrictor assembly to change the position of the restrictor relative to the inlet portion. 
     
     
         6 . A constant-flow valve assembly, comprising:
 a body with a fluid inlet, a fluid outlet, a fluid passageway therebetween, the fluid passageway having a first portion containing fluid at a first fluid pressure, a second portion containing fluid at a second fluid pressure less than the first fluid pressure, and a third portion containing fluid at a third fluid pressure less than the second fluid pressure;   an adjustable flow restriction between the second and third fluid passageways and configured to provide a substantially constant fluid flow to the third passageway substantially independent of the pressure differentials between the second and third fluid pressures, the adjustable flow restriction comprising a biased valve member having a piston moveable relative to the body, a piston biasing member engaging the piston and having a piston biasing tension, and a biased valve coupled to the fluid passageway; and   an adjustable restrictor assembly between the first and second fluid passageways, the restrictor assembly having an inlet portion, an outlet portion, and a restrictor with a fluid pathway extending therebetween, the inlet portion being positioned to receive fluid at the first fluid pressure from the first fluid passageway and to direct the fluid to the restrictor, and the outlet portion being positioned to receive fluid from the restrictor and direct fluid to the second fluid passageway at the second fluid pressure, the restrictor having an entry portion and an exit portion of the fluid pathway, the restrictor being movable to simultaneously adjust the piston biasing tension of the piston biasing member and adjust the position of the entry and exit portions relative to the inlet and outlet portions to adjust a fluid flow rate of fluid through fluid pathway to the second fluid passageway and to automatically adjust the biased valve member for a constant flow rate through the valve assembly.   
     
     
         7 . The assembly of clam  6  wherein the restrictor has an outer surface, the fluid pathway includes the entry portion defined by a plurality of blind notches interconnected by at least one blind channel and in fluid communication with a through hole, the restrictor being movable to allow the inlet portion to interfere with at least a portion of the entry portion to adjustably restrict the fluid flow into the blind notches, blind channel, or through hole and to control the fluid flow rate through the adjustable restrictor assembly. 
     
     
         8 . The assembly of  claim 6 , further comprising an external adjustment device coupled to the restrictor assembly, the adjustment device being manipulatable to move the restrictor assembly to change the position of the restrictor relative to the inlet portion. 
     
     
         9 . The assembly of clam  6  wherein the restrictor has an outer surface, the fluid pathway includes the exit portion defined by at least one a blind notch in the outer surface and in fluid communication with a through hole, the restrictor being movable to allow the outlet portion to interfere with at least a portion of the exit portion to adjustably restrict the fluid flow into through the restrictor and to control the fluid flow rate through the adjustable restrictor assembly. 
     
     
         10 . A constant-flow valve assembly, comprising:
 a first fluid passageway configured to carry fluid at a first fluid pressure;   a chamber having at least a portion configured to receive fluid at a second fluid pressure less than the first fluid pressure;   a second fluid passageway connected to the portion of the piston chamber and configured to carry fluid at the second fluid pressure;   a third fluid passageway configured to carry fluid at a third fluid pressure less than the first and second fluid pressures;   a piston slideably disposed in the chamber;   a biased valve member having a valve seat adjacent to the third passageway, a valve body, a first biasing member coupled-connected to the piston and having a piston biasing tension, and a second biasing member engaging the valve body, the first biasing member urging the piston away from the valve seat, and the valve body being urged by the second biasing member toward the valve seat and configured to provide a substantially constant fluid flow to the third passageway past the valve seat substantially independent of the pressure differentials between the second and third fluid pressures; and   an adjustable restrictor assembly between the first and second fluid passageways, the restrictor assembly having an inlet portion, an outlet portion, and a restrictor with a fluid pathway extending therebetween, the inlet portion being positioned to receive fluid at the first fluid pressure from the first fluid passageway and to direct the fluid to the restrictor, and the outlet portion being positioned to receive fluid from the restrictor and direct fluid to the second fluid passageway at the second fluid pressure, the restrictor having an entry portion and an exit portion of the fluid pathway, the restrictor being movable to simultaneously adjust the piston biasing tension of the first biasing member and adjust the position of the entry and exit portions relative to the inlet and outlet portions to adjust a fluid flow rate of fluid through fluid pathway to the second fluid passageway and to automatically adjust the piston and the biased valve member for a constant flow rate of fluid through the valve assembly.   
     
     
         11 . The assembly of clam  10  wherein the restrictor has an outer surface, the fluid pathway includes the entry portion defined by at least one a blind notch in the outer surface and in fluid communication with a through hole, the restrictor being movable to allow the inlet portion to interfere with at least a portion of the entry portion to adjustably restrict the fluid flow into through the restrictor and to control the fluid flow rate through the adjustable restrictor assembly. 
     
     
         12 . The assembly of clam  10  wherein the restrictor has an outer surface, the fluid pathway includes the entry portion defined by a plurality of blind notches interconnected by at least one blind channel and in fluid communication with a through hole, the restrictor being movable to allow the inlet portion to interfere with at least a portion of the entry portion to adjustably restrict the fluid flow into the blind notches, blind channel, or through hole and to control the fluid flow rate through the adjustable restrictor assembly. 
     
     
         13 . The assembly of  claim 12  wherein the restrictor body is movable so at least a portion of the through hole remains uncovered and at least one blind notch adjacent to the through hole is fully covered, whereby the through hold receives a fluid simultaneously in parallel from the covered blind notch and directly from the inlet portion. 
     
     
         14 . The assembly of  claim 10  wherein the restrictor includes an exterior surface with the entry portion thereon, and the inlet portion includes a body segment with an aperture in fluid communication with the first fluid passageway and with the entry portion, the body segment engaging the exterior surface of the restrictor body so at least a portion of the aperture is in direct fluid communication with the entry portion. 
     
     
         15 . The assembly of  claim 10 , further comprising an external adjustment device coupled to the restrictor assembly, the adjustment device being manipulatable to move the restrictor assembly to change the position of the restrictor relative to the inlet portion. 
     
     
         16 . The assembly of clam  10  wherein the restrictor has an outer surface, the fluid pathway includes the exit portion defined by at least one a blind notch in the outer surface and in fluid communication with a through hole, the restrictor being movable to allow the outlet portion to interfere with at least a portion of the exit portion to adjustably restrict the fluid flow into through the restrictor and to control the fluid flow rate through the adjustable restrictor assembly. 
     
     
         17 . A constant-flow valve assembly, comprising:
 a body with a fluid inlet, a fluid outlet, a fluid passageway therebetween, the fluid passageway having a first portion containing fluid at a first fluid pressure, a second portion containing fluid at a second fluid pressure less than the first fluid pressure, and a third portion containing fluid at a third fluid pressure less than the second fluid pressure;   an adjustable valve member in the fluid passageway and configured to provide a constant fluid flow rate from the fluid outlet independent of pressure differentials between the first, second and third fluid pressures, the adjustable valve member having a piston slidably disposed in the body, a first biasing member engaging the piston and having a piston biasing tension, a valve seat adjacent to the fluid passageway, a valve body coupled to the piston, and a second biasing member urging the valve body toward the valve seat; and   an adjustable restrictor assembly between the first and second fluid passageways, the restrictor assembly having an inlet portion, an outlet portion, and a restrictor with a fluid pathway extending therebetween, the inlet portion being positioned to receive fluid at the first fluid pressure from the first fluid passageway and to direct the fluid to the restrictor, and the outlet portion being positioned to receive fluid from the restrictor and direct fluid to the second fluid passageway at the second fluid pressure, the restrictor having an entry portion and an exit portion of the fluid pathway, the restrictor being movable to adjust the position of the entry and exit portions relative to the inlet and outlet portions to simultaneously adjust a fluid flow rate of fluid through fluid pathway to the second fluid passageway and adjust the piston biasing tension of the first biasing member to automatically adjust the adjustable valve member for a constant flow rate of fluid exiting the fluid outlet.   
     
     
         18 . The assembly of clam  17  wherein the restrictor has an outer surface, the fluid pathway includes the entry portion defined by at least one a blind notch in the outer surface and in fluid communication with a through hole, the restrictor being movable to allow the inlet portion to interfere with at least a portion of the entry portion to adjustably restrict the fluid flow into through the restrictor and to control the fluid flow rate through the adjustable restrictor assembly. 
     
     
         19 . The assembly of clam  17  wherein the restrictor has an outer surface, the fluid pathway includes the entry portion defined by a plurality of blind notches interconnected by at least one blind channel and in fluid communication with a through hole, the restrictor being movable to allow the inlet portion to interfere with at least a portion of the entry portion to adjustably restrict the fluid flow into the blind notches, blind channel, or through hole and to control the fluid flow rate through the adjustable restrictor assembly. 
     
     
         20 . A constant-flow valve assembly, comprising:
 a first fluid passageway with fluid at a first fluid pressure;   a chamber containing fluid at a second fluid pressure less than the first fluid pressure;   a second fluid passageway connected to the portion of the chamber and containing fluid at the second fluid pressure;   a third fluid passageway with fluid at a third fluid pressure less than the first and second fluid pressures;   a piston slideably disposed in the chamber;   a biased valve member having a valve seat adjacent to the third passageway, a valve body, a first biasing member coupled to the piston and having a piston biasing tension, and a second biasing member engaging the valve body, the first biasing member urging the piston away from the valve seat, the valve body being urged by the second biasing member toward the valve seat and configured to provide a substantially constant fluid flow to the third passageway past the valve seat substantially independent of the pressure differentials between the second and third fluid pressures; and   a restrictor assembly between the first and second fluid passageways, the restrictor assembly having a first sealing pad, a second sealing pad, and a restrictor with a fluid pathway extending therebetween, the first sealing pad engaging the restrictor and being positioned to receive fluid at the first fluid pressure from the first fluid passageway and to direct the fluid to the restrictor, and the second sealing pad engaging the restrictor and being positioned to receive fluid from the restrictor and direct fluid to the second fluid passageway at the second fluid pressure, the restrictor being movable to adjust the position of the fluid pathway relative to the inlet and outlet portions to simultaneously adjust the piston biasing tension of the first biasing member and adjust a fluid flow rate of fluid through fluid pathway to the second fluid passageway, thereby automatically adjusting the piston and the biased valve member to provide a substantially continuous flow rate through the valve assembly independent of the pressure differentials.   
     
     
         21 . The assembly of clam  20  wherein the restrictor has an outer surface, the fluid pathway includes the entry portion defined by at least one a blind notch in the outer surface and in fluid communication with a through hole, the restrictor being movable to allow the first sealing pad to cover at least a portion of the entry portion to adjustably restrict the fluid flow into through the restrictor and to control the fluid flow rate through the adjustable restrictor assembly. 
     
     
         22 . The assembly of clam  20  wherein the restrictor has an outer surface, the fluid pathway includes the entry portion defined by a plurality of blind notches interconnected by at least one blind channel and in fluid communication with a through hole, the restrictor being movable to allow the first sealing pad to interfere with at least a portion of the entry portion to adjustably restrict the fluid flow into the blind notches, blind channel, or through hole and to control the fluid flow rate through the adjustable restrictor assembly. 
     
     
         23 . The assembly of  claim 20  wherein the restrictor comprises a sleeve with an interior area and a central member disposed in the interior area, the fluid pathway extends through the sleeve and around the central member. 
     
     
         24 . The assembly of  claim 20 , further comprising an external adjustment device coupled to the restrictor assembly, the adjustment device being manipulatable to move the restrictor assembly to change the position of the restrictor relative to at least one of the first and second sealing pads. 
     
     
         25 . A constant-flow valve assembly, comprising:
 a body portion having a first fluid inlet, a piston chamber, and a first fluid outlet, the first fluid inlet configured to receive fluid at a first fluid pressure, the piston chamber having a first portion exposed to the fluid at the first fluid pressure and having a second portion exposed to fluid having a second fluid pressure less than the first fluid pressure, and the first fluid outlet configured to carry fluid at a third fluid pressure less than the first and second fluid pressures;   a piston slideably disposed in the piston chamber;   a first biasing member in the chamber and urging the piston away from the fluid passageway, the first biasing member having a piston biasing tension;   a seal in the piston chamber between the piston and the body and separating one portion of the fluid at the first fluid pressure and another portion of the fluid at the second fluid pressure;   a valve member coupled to the piston in the second portion of the piston chamber and having a valve body and a second biasing member urging the valve body toward the fluid passageway, and configured to provide a substantially constant fluid flow from the second portion of the piston chamber toward the outlet substantially independent of the pressure differentials between the first, second, and third fluid pressures;   a first fluid passageway connected to the first portion of the piston chamber and configured to contain fluid at the first fluid pressure;   a second fluid passageway connected to the second portion of the piston chamber and configured to contain fluid at the second fluid pressure; and   an adjustable restrictor assembly coupled to the body between the first and second fluid passageways, the restrictor assembly having a second inlet, a second outlet, and restrictor body with a fluid pathway extending therebetween, the second inlet positioned to receive fluid from the first fluid passageway, and the second outlet positioned to direct fluid to the second fluid passageway, the restrictor body having an entry portion and an exit portion of the fluid pathway, the restrictor body having an outer surface with at least one a blind channel in fluid communication with an aperture to define the entry portion, the restrictor body being movable relative to the second inlet to cover at least a portion of the aperture and the blind channel on the outer surface to adjust the fluid flow rate through the flow pathway to the exit portion, thereby simultaneously adjusting the piston biasing tension and adjusting the flow rate through the valve assembly independent of the differences in the first, second, and third fluid pressures.   
     
     
         26 . (canceled) 
     
     
         27 . (canceled) 
     
     
         28 . (canceled) 
     
     
         29 . The assembly of  claim 25  wherein the restrictor body comprises a sleeve with an interior area and a central member disposed in the interior area, the fluid pathway extends through the sleeve and around the central member. 
     
     
         30 . The assembly of  claim 25  wherein the restrictor body is a shaft with an aperture therethrough, the fluid pathway extending through the aperture in the shaft. 
     
     
         31 . The assembly of  claim 25  wherein the restrictor body includes an exterior surface with the entry portion thereon, and the second inlet includes a body segment with an aperture in fluid communication with the first fluid passageway and with the entry portion, the body segment engaging the exterior surface of the restrictor body so at least a portion of the aperture is in direct fluid communication with the entry portion. 
     
     
         32 . The assembly of  claim 25 , further comprising an external adjustment device coupled to the restrictor assembly, the adjustment device being manipulatable to move the restrictor assembly to change the position of the restrictor body relative to the second inlet. 
     
     
         33 . (canceled) 
     
     
         34 . (canceled) 
     
     
         35 . The assembly of  claim 27  wherein the restrictor body is movable so at least a portion of the aperture remains uncovered and at least one blind receptacle adjacent to the aperture is fully covered. 
     
     
         36 . The assembly of  claim 25  wherein the restrictor body includes an exterior surface with the exit portion thereon, and the second outlet includes a body segment with an aperture therethrough in fluid communication with the first fluid passageway and with the entry portion, the body segment sealably engaging the exterior surface of the restrictor body so at least a portion of the aperture is in direct fluid communication with the exit portion. 
     
     
         37 . The control valve assembly of  claim 25  wherein the restrictor body of the adjustable restrictor assembly is a portion of a central shaft, the central shaft having an end portion having a passageway therein adjacent to the valve member and configured to direct fluid from the valve member to the outlet.