Fluid pressure control valve

Abstract

A valve assembly configured to provide feed-back control of pressurized fluid in a gallery includes a housing and a pressure chamber. The valve assembly also includes a first passage for providing continuous flow of fluid through the gallery and a second passage for supplying the pressurized fluid to the gallery. The valve assembly additionally includes a piston moveable within the pressure chamber between a first position that opens the second passage and a second position that closes the second passage. The piston includes a third passage that provides fluid communication between the first passage and the pressure chamber. Furthermore, the valve assembly includes a spring configured to move the piston to the first position when gallery fluid pressure is less than a threshold pressure value and permit the piston to shift to the second position when gallery fluid pressure is equal to or greater than the threshold pressure value.

1 . A valve assembly configured to provide feed-back control of pressurized fluid in a gallery, the valve assembly comprising:
 a housing;   a pressure chamber;   a first passage configured to provide continuous flow of fluid through the gallery;   a second passage configured to supply the pressurized fluid from an external source to the gallery;   a piston configured to move within the pressure chamber between a first position and a second position and having a third passage configured to establish fluid communication between the first passage and the pressure chamber, wherein the first position of the piston opens the second passage and the second position of the piston closes the second passage; and   a spring disposed between the piston and the housing, the spring being configured to move the piston to the first position when pressure of the fluid in the gallery is less than a threshold fluid pressure value and permit the piston to move to the second position when pressure of the fluid in the gallery is equal to or greater than the threshold fluid pressure value.   
     
     
         2 . The valve assembly of  claim 1 , wherein the pressure chamber includes a reaction surface configured to generate a hydraulic force sufficient to overcome the spring and move the piston to the second position when the fluid pressure is at or above the threshold fluid pressure value. 
     
     
         3 . The valve assembly of  claim 2 , further comprising a cap assembled onto the housing, wherein the reaction surface is arranged on the cap. 
     
     
         4 . The valve assembly of  claim 1 , wherein the third passage is arranged substantially perpendicular to the first passage. 
     
     
         5 . The valve assembly of  claim 1 , further comprising a fourth passage configured to purge fluid that escapes from the pressure chamber past the piston. 
     
     
         6 . The valve assembly of  claim 1 , wherein the third passage includes an orifice configured to establish a rate of movement of the piston within the pressure chamber in response to fluid pressure changes in the gallery. 
     
     
         7 . The valve assembly of  claim 1 , wherein the external source supplying pressurized fluid to the gallery is a fluid pump. 
     
     
         8 . The valve assembly of  claim 1 , wherein the gallery is arranged in an internal combustion engine, the fluid is engine oil, and the gallery is configured to supply the oil to a hydraulic lash adjuster in a valve train system of the engine. 
     
     
         9 . An internal combustion engine comprising:
 a cylinder;   a valve train system configured to open and close an entryway into the cylinder and having a hydraulic lash adjuster configured to control a clearance in the valve train;   a pump configured to pressurize an oil;   a gallery configured to supply the pressurized oil to the lash adjuster; and   a valve assembly configured to provide feed-back control of the pressurized oil in a gallery, the valve assembly comprising:
 a housing; 
 a pressure chamber; 
 a first passage configured to provide continuous flow of oil through the gallery; 
 a second passage configured to supply the pressurized oil from the pump to the gallery; 
 a piston configured to move within the pressure chamber between a first position and a second position and having a third passage configured to establish fluid communication between the first passage and the pressure chamber, wherein the first position of the piston opens the second passage and the second position of the piston closes the second passage; and 
 a spring disposed between the piston and the housing, the spring being configured to move the piston to the first position when pressure of the oil in the gallery is less than a threshold oil pressure value and permit the piston to move to the second position when pressure of the oil in the gallery is equal to or greater than the threshold oil pressure value. 
   
     
     
         10 . The engine of  claim 9 , wherein the pressure chamber includes a reaction surface configured to generate a hydraulic force sufficient to overcome the spring and move the piston to the second position when the oil pressure is at or above the threshold oil pressure value. 
     
     
         11 . The engine of  claim 10 , wherein the valve assembly additionally includes a cap assembled onto the housing, and wherein the reaction surface is arranged on the cap. 
     
     
         12 . The engine of  claim 9 , wherein the third passage is arranged substantially perpendicular to the first passage. 
     
     
         13 . The engine of  claim 9 , wherein the valve assembly additionally includes a fourth passage configured to purge oil that escapes from the pressure chamber past the piston. 
     
     
         14 . The engine of  claim 9 , wherein the third passage includes an orifice configured to establish a rate of movement of the piston within the pressure chamber in response to oil pressure changes in the gallery. 
     
     
         15 . A vehicle comprising:
 a drive element; and   an internal combustion engine configured to generate torque for rotating the drive element, the engine having:
 a cylinder; 
 a valve train system configured to open and close an entryway into the cylinder and having a hydraulic lash adjuster configured to control a clearance in the valve train; 
 a pump configured to pressurize an oil; 
 a gallery configured to supply the pressurized oil to the lash adjuster; and 
 a valve assembly configured to provide feed-back control of the pressurized oil in a gallery, the valve assembly comprising:
 a housing; 
 a pressure chamber; 
 a first passage configured to provide continuous flow of oil through the gallery; 
 a second passage configured to supply the pressurized oil from the pump to the gallery; 
 a piston configured to move within the pressure chamber between a first position and a second position and having a third passage configured to establish fluid communication between the first passage and the pressure chamber, wherein the first position of the piston opens the second passage and the second position of the piston closes the second passage; and 
 a spring disposed between the piston and the housing, the spring being configured to move the piston to the first position when pressure of the oil in the gallery is less than a threshold oil pressure value and permit the piston to move to the second position when pressure of the oil in the gallery is equal to or greater than the threshold oil pressure value. 
 
   
     
     
         16 . The vehicle of  claim 15 , wherein the pressure chamber includes a reaction surface configured to generate a hydraulic force sufficient to overcome the spring and move the piston to the second position when the oil pressure is at or above the threshold oil pressure value. 
     
     
         17 . The vehicle of  claim 16 , wherein the valve assembly additionally includes a cap assembled onto the housing, and wherein the reaction surface is arranged on the cap. 
     
     
         18 . The vehicle of  claim 15 , wherein the third passage is arranged substantially perpendicular to the first passage. 
     
     
         19 . The vehicle of  claim 15 , wherein the valve assembly additionally includes a fourth passage configured to purge oil that escapes from the pressure chamber past the piston. 
     
     
         20 . The vehicle of  claim 15 , wherein the third passage includes an orifice configured to establish a rate of movement of the piston within the pressure chamber in response to oil pressure changes in the gallery.