Cavitation-deterring energy-efficient fluid pump system and method of operation

Abstract

A variable nozzle area jet pump is provided having a nozzle-sealing member resiliently urged to form a sealing closure. The sealing member is part of a normally non-passing pressure control valve that recirculates excess fluid back to the inlet of a positive displacement fluid pump. The fluid is recirculated with elevated pressure after a threshold fluid pressure is exceeded. The disclosed system provides for energy conservation and pump cavitation speed increase. The system may be integrated with an engine balance shaft module so as to provide low cost robustness to low speed gear noise emissions by application of the oil pump's drive torque to at lease one gearset.

1 . A pump system comprising:
 a first positive displacement pump having an inlet passage and a discharge passage; and   an adjustable nozzle jet pump valve having:   a supply chamber fluidly coupled to said discharge passage, said supply chamber further having a port with a seat surface;   a movable valve member having a sealing surface in sealing contact with said seat surface when in a first position, and a body portion, said body portion further having a first face sealingly positioned within said supply chamber, and an opposing second face, said first face having a first surface area;   an urging member coupled to said second face;   a suction chamber fluidly coupled to said port;   a throat passage fluidly coupled to said suction chamber and said inlet passage   wherein said port, said suction chamber and said throat passage are arranged in a continuous serial fluid connection to said inlet passage.   
     
     
         2 . The pump system of  claim 1  wherein said adjustable nozzle jet pump valve includes an orifice fluidly coupled to said second face. 
     
     
         3 . The pump system of  claim 2  wherein said orifice is vented to atmospheric pressure. 
     
     
         4 . The pump system of  claim 2  wherein said venting to atmospheric pressure is by means of fluid coupling with an oil reservoir exposed to atmospheric pressure. 
     
     
         5 . The pump system of  claim 1  wherein said urging member is a spring arranged to bias said movable valve member sealing surface against said seat. 
     
     
         6 . The pump system of  claim 1  wherein said urging member is an electromechanical actuator. 
     
     
         7 . The pump system of  claim 1  further comprising:
 an uptake passage fluidly coupled to said suction chamber and to a fluid reservoir; and,   a one-way check valve fluidly coupled between a fluid reservoir and said inlet passage.   
     
     
         8 . The pump system of  claim 1  wherein said throat passage comprises an entry bell for smoothing the acceleration of flows entering said throat passage, said entry bell having outside diameter larger than an outside diameter circumscribing said throat passage. 
     
     
         9 . The pump system of  claim 1  wherein said adjustable nozzle jet pump valve includes a diaphragm member coupled to said body portion. 
     
     
         10 . The pump system of  claim 1  wherein said adjustable nozzle jet pump valve includes a bellows member coupled to said body portion. 
     
     
         11 . The pump system of  claim 1  further comprising:
 a fluid reservoir fluidly coupled to said suction chamber; and,   a second positive displacement pump fluidly coupled between said fluid reservoir and said discharge passage.   
     
     
         12 . The pump system of  claim 1  wherein said adjustable nozzle jet pump valve further comprises a pilot chamber positioned between said body member and said supply chamber. 
     
     
         13 . A pump system for a variable consumptive load, said system comprising:
 a first positive displacement pump, said pump having an inlet passage and a discharge passage, wherein said discharge passage is arranged to couple with said variable consumptive load;   a jet pump valve having a variable nozzle opening area fluidly coupled between said discharge passage and said inlet passage, said jet pump valve including means for changing the area of said variable nozzle opening in direct response to changes in fluid pressure in said discharge passage, said jet pump valve further including an urging member arranged to bias a member to close said variable nozzle opening;   said jet pump valve further having a suction chamber adjacent said variable nozzle opening and arranged to receive fluid from said variable nozzle opening and from a fluid reservoir;   said jet pump valve further having a throat passage coupled to said suction chamber, said throat passage being fluidly coupled to receive fluid from said reservoir and from said variable valve opening, and to transfer said received fluid to said inlet passage.   
     
     
         14 . The pump system of  claim 13  wherein:
 said means for changing the size of said variable nozzle opening comprises:   a supply chamber in direct fluid connection to said discharge line; and,   a valve body movable between a first position and a second position, said valve body having a sealing member with a first cross sectional area and a first face with a second surface, where in said second surface's area is greater than said first cross sectional area, and wherein said sealing member is in contact with and closes said variable nozzle opening when said valve body is in said first position.   
     
     
         15 . The pump system of  claim 14  further comprising a damping chamber, wherein a portion of said valve body forms a portion of one side of said damping chamber. 
     
     
         16 . The pump system of  claim 15  further comprising a damping orifice fluidly coupled to said damping chamber. 
     
     
         17 . The pump system of  claim 16  wherein said damping orifice is vented to atmospheric pressure by means of fluid coupling with an oil reservoir exposed to atmospheric pressure. 
     
     
         18 . The pump system of  claim 13  further comprising:
 a fluid reservoir fluidly coupled to said first positive displacement pump; and,   a second positive displacement pump fluidly coupled between to said fluid reservoir and said discharge passage.   
     
     
         19 . The pump system of  claim 18  further comprising a bypass passage fluidly coupled to said supply chamber when said valve body is in said second position. 
     
     
         20 . The pump system of  claim 13  further comprising a one way check valve fluidly coupled between said reservoir and said inlet passage adjacent one end of said throat passage opposite said inlet transition region. 
     
     
         21 . The pump system of  claim 20  wherein said valve is a ball and seat type valve or a reed type valve. 
     
     
         22 . The pump system of  claim 20  wherein said valve includes a member having a substantially cup-shaped cross-section, and a seat, said cup shape having sides which slidingly engage a pilot member for locating of a face area of said cup-shaped member in sealable proximity to said seat. 
     
     
         23 . The pump system of  claim 13  wherein said urging member is a compression spring. 
     
     
         24 . The pump system of  claim 13  wherein said urging member is an electromechanical actuator. 
     
     
         25 . The pump system of  claim 14  further comprising a pilot pressure chamber adjacent said first face, wherein said pilot pressure chamber having a partition wall that inhibits flow from said supply chamber to said pilot pressure chamber. 
     
     
         26 . The pump system of  claim 25  further comprising a seal arranged between said supply chamber and said pilot pressure chamber. 
     
     
         27 . The pump system of  claim 13  wherein said throat passage further includes an inlet transition region coupled to said suction chamber. 
     
     
         28 . The pump system of  claim 13  wherein said means for changing the area of said variable nozzle opening is in direct response to changes in fluid pressure in said consumptive load. 
     
     
         29 . The pump system of  claim 13  further comprising an actuator movable between a first position and a second position, said actuator being coupled to said urging member, wherein said urging member provides a first force when said actuator is in said first position and a second force when said actuator is in said second position. 
     
     
         30 . A method of operating a pump system comprising:
 pressurizing a fluid with a positive displacement pump;   discharging said fluid into a discharge passage;   flowing a portion of said fluid from said discharge passage directly into a valve supply chamber;   applying pressure to a valve body face;   moving said valve body;   opening a port in said valve supply chamber;   ejecting said fluid into a suction chamber; and,   increasing the fluid pressure at an inlet to said displacement pump by injecting said fluid across a suction chamber into a throat passage which also receives fluid from a reservoir by means of said suction chamber.   
     
     
         31 . The method of  claim 30  further comprising the step of varying the opening area of said port in direct response to changes in pressure of said fluid in said outlet passage. 
     
     
         32 . The method of  claim 31  further comprising the steps of:
 adducting fluid in said suction chamber towards said injected fluid;   flowing said adducted fluid and said injected fluid into a throat passage;   flowing said adducted and injected fluids to said displacement pump inlet.   
     
     
         33 . The method of  claim 30  further comprising the step of biasing said valve body towards said port. 
     
     
         34 . The method of  claim 33  wherein said step of moving said valve body occurs if the pressure in said discharge passage increases beyond a first threshold. 
     
     
         35 . The method of  claim 34  further comprising the step of opening a one-way valve fluidly coupled to said inlet if pressure at said inlet is less than a second threshold. 
     
     
         36 . The method of  claim 30  further comprising the step of powering said positive displacement pump by driving connectivity with a balance shaft for an internal combustion engine having at least one piston and connecting rod assembly. 
     
     
         37 . The method of  claim 36  further comprising the step of transferring said fluid to said internal combustion engine. 
     
     
         38 . The method of  claim 29  further comprising the steps of:
 applying a force with an urging member to said valve body; and,   changing the magnitude of said force in response to a switching event.   
     
     
         39 . An internal combustion engine comprising:
 a balance shaft assembly;   a first positive displacement pump, said pump having an inlet passage and a discharge passage, wherein said discharge passage is arranged to fluidly couple with said balance shaft assembly;   a jet pump valve having a variable nozzle opening area fluidly coupled between said discharge passage and said inlet passage, said jet pump valve including means for changing the area of said variable nozzle opening in direct response to changes in fluid pressure in said discharge passage, said jet pump valve further including an urging member arranged to bias a member to close said variable nozzle opening;   said jet pump valve further having a suction chamber adjacent said variable nozzle opening and arranged to receive fluid from said variable nozzle opening and a fluid reservoir; and,   said jet pump valve further having a throat passage coupled to said suction chamber, said throat passage being fluidly coupled to receive fluid from said reservoir and said variable valve opening and transfer said received fluid to said inlet passage.   
     
     
         40 . The internal combustion engine of  claim 39  wherein said means for changing the area of said variable nozzle opening is in direct response to changes in fluid pressure in said internal combustion engine. 
     
     
         41 . The internal combustion engine of  claim 39  further comprising an actuator movable between a first position and a second position, said actuator being operably coupled to said urging member wherein said urging member provides a first force when said actuator is in said first position and a second force when said actuator is in said second position.