Fluid flow pressure regulator

Abstract

A fuel vapor pressure regulator by which the input pressure of an input fluid is regulated by the opening and closing of a valve unit controlled by a piston pressure sensor, the operation of which is, in turn, controlled by a movement of a preset bias, the output pressure of the fluid delivered by the regulator, and a biasing pressure that reflects the operating demands of the utilization unit to which the fluid is delivered.

What is claimed:  
     
         1 . A fuel vapor pressure regulator comprising: 
 a housing having: 
 (a) an inlet port through which a fuel is introduced at an input pressure,  
 (b) an outlet port through which the fuel is discharged at an output pressure,  
 (c) a bias port through which a biasing pressure is introduced;  
   a valve unit in said housing between said inlet port and said outlet port for regulating the pressure of fuel flow from said inlet port to said outlet port;    a piston in said housing coupled to said valve unit and responsive to: 
 (a) the output pressure at the outlet port for urging said valve unit toward closing, and  
 (b) the biasing pressure introduced through said bias port for one of: 
 (1) urging said valve toward closing, and  
 (2) urging said valve to open; and  
 
   a spring acting on said piston against the outlet pressure to urge said valve unit to close.    
     
     
         2 . A fuel vapor pressure regulator according to  claim 1  wherein: 
 (a) the biasing pressure introduced at said bias port is a partial vacuum, and  
 (b) said piston has: 
 (1) a first face that receives the output pressure at said outlet port for urging said valve unit toward closing, and  
 (2) a second face that receives the partial vacuum for urging said valve unit toward closing.  
 
 
     
     
         3 . A fluid flow pressure regulator according to  claim 2  wherein the area of said first face of said piston and the area of said second face of said piston are the same.  
     
     
         4 . A fluid flow pressure regulator according to  claim 2  wherein the area of said first face of said piston is greater than the area of said second face of said piston.  
     
     
         5 . A fluid flow pressure regulator according to  claim 2  wherein the area of said first face of said piston is less than the area of said second face of said piston.  
     
     
         6 . A fuel vapor pressure regulator according to  claim 1  wherein: 
 (a) the biasing pressure introduced at said bias port is greater than atmospheric pressure, and  
 (b) said piston has: 
 (1) a first face that receives the output pressure at said outlet port for urging said valve unit toward closing, and  
 (2) a second face that receives the biasing pressure introduced at said bias port for urging said valve to open.  
 
 
     
     
         7 . A fluid flow pressure regulator according to  claim 6  wherein the area of said first face of said piston and the area of said second face of said piston are the same.  
     
     
         8 . A fluid flow pressure regulator according to  claim 6  wherein the area of said first face of said piston is greater than the area of said second face of said piston.  
     
     
         9 . A fluid flow pressure regulator according to  claim 6  wherein the area of said first face of said piston is greater than the area of said second face of said piston.  
     
     
         10 . A fluid flow pressure regulator comprising: 
 a housing having: 
 (a) an inlet port through which a fluid is introduced at a supply pressure,  
 (b) an outlet port through which the fluid is discharged at an output pressure,  
 (c) a bias port through which a biasing pressure is introduced,  
 (d) a cavity in fluid communication with said bias port, and  
 (e) an aspirator passage extending between said outlet port and said cavity through which the output pressure is conducted from said outlet port to said cavity; and  
   a valve assembly within said housing for regulating the pressure of fluid flow from said inlet port to said outlet port and having: 
 (a) a nozzle between said inlet port and said outlet port through which fluid flows from said inlet port to said outlet port,  
 (b) a valve movable toward said nozzle and away from said nozzle,  
 (c) means for urging said valve toward said nozzle,  
 (d) a pressure set point assembly in said cavity and having: 
 (1) a piston pressure sensor, and  
 (2) means acting on said piston pressure sensor for urging said valve away from said nozzle, and  
 
 (e) a coupling extending between said piston pressure sensor and said valve, and  
   responsive to: 
 (a) the output pressure conducted from said outlet port through said aspirator passage to said piston pressure sensor for urging said valve toward said nozzle, and  
 (b) the biasing pressure introduced through said bias port to said piston pressure sensor for one of: 
 (1) urging said valve toward said nozzle, and  
 (2) urging said valve away from said nozzle.  
 
   
     
     
         11 . A fluid flow pressure regulator according to  claim 10  wherein: 
 (a) said means for urging said valve toward said nozzle include a first spring having an end bearing against said valve,  
 (b) said means for urging said valve away from said nozzle include a second spring, and  
 (c) said piston pressure sensor has: 
 (1) a first face: 
 (i) against which an end of said second spring bears urging said valve away from said nozzle, and  
 (ii) that receives biasing pressure from said bias port for one of: 
 urging said valve toward said nozzle, and  
 urging said valve away from said nozzle, and  
 
 
 (2) a second face that receives output fluid pressure conducted from said outlet port through said aspirator passage for urging said valve toward said nozzle.  
 
 
     
     
         12 . A fluid flow pressure regulator according to  claim 11  wherein said piston pressure sensor divides said cavity into a first part that receives output fluid pressure conducted from said outlet port through said aspirator passage and a second part that receives biasing pressure from said bias port.  
     
     
         13 . A fluid flow pressure regulator according to  claim 12  wherein said valve assembly further includes a balanced valve having: 
 (a) a piston cylinder,  
 (b) a balance piston movable within said piston cylinder and coupled to said piston of said pressure set point assembly through said valve,  
 (c) a seal between said balance piston and said piston cylinder, and  
 (d) a pressure equalization passage extending through said valve and said balance piston from said first part of said cavity.  
 
     
     
         14 . A fluid flow pressure regulator according to  claim 10  wherein the biasing pressure is a partial vacuum.  
     
     
         15 . A fluid flow pressure regulator according to  claim 10  wherein the biasing pressure is greater than atmospheric pressure.  
     
     
         16 . A fluid flow pressure regulator according to  claim 11  wherein the area of said first face of said piston pressure sensor and the area of said second face of said piston pressure sensor are the same.  
     
     
         17 . A fluid flow pressure regulator according to  claim 11  wherein the area of said first face of said piston pressure sensor is greater than the area of said second face of said piston pressure sensor.  
     
     
         18 . A fluid flow pressure regulator according to  claim 11  wherein the area of said first face of said piston pressure sensor is less than the area of said second face of said piston pressure sensor.  
     
     
         19 . A fluid delivery system comprising: 
 supply means for supplying a fluid at a supply pressure;    utilization means for utilizing the fluid delivered at an output pressure; and    a fluid flow pressure regulator disposed between said supply means and said utilization means and including: 
 (a) a housing having: 
 (1) an inlet port through which a fluid is introduced at a supply pressure,  
 (2) an outlet port through which the fluid is discharged at an output pressure,  
 (3) a bias port through which a biasing pressure is introduced,  
 (4) a cavity in fluid communication with said bias port, and  
 (5) an aspirator passage extending between said outlet port and said cavity through which the output pressure is conducted from said outlet port to said cavity; and  
 
 (b) a valve assembly within said housing for regulating the pressure of fluid flow from said inlet port to said outlet port and having: 
 (1) a nozzle between said inlet port and said outlet port through which fluid flows from said inlet port to said outlet port,  
 (2) a valve movable toward said nozzle and away from said nozzle,  
 (3) means for urging said valve toward said nozzle,  
 (4) a pressure set point assembly in said cavity and having: 
 (i) a piston pressure sensor, and  
 (ii) means acting on said piston pressure sensor for urging said valve away from said nozzle, and  
 
 (5) a coupling extending between said piston pressure sensor and said valve, and responsive to:  
 (1) the output pressure conducted from said outlet port through said aspirator passage to said piston pressure sensor for urging said valve toward said nozzle, and  
 (2) the biasing pressure introduced through said bias port to said piston pressure sensor for one of: 
 (i) urging said valve toward said nozzle, and  
 (ii) urging said valve away from said nozzle.  
 
 
   
     
     
         20 . A fluid delivery system according to  claim 19  further including one of a vacuum source and a pressure source for providing the biasing pressure.