Fluid pump and method

Abstract

An internal combustion engine ( 200 ) includes a fluid pump ( 220 ) having an inlet ( 218 ), a low pressure outlet ( 223 ), and a high pressure outlet ( 222 ). A reservoir ( 226 ) is connected to the high pressure outlet ( 222 ) and an oil sump ( 204 ) is in fluid communication with the inlet ( 218 ). A pressure regulating valve ( 228 ) connects the high pressure outlet ( 222 ) and the low pressure outlet ( 223 ). A recirculation passage ( 227 ) fluidly connects the low pressure outlet ( 223 ) with the inlet ( 218 ). A flow of oil at a high pressure in the high pressure outlet ( 222 ) passes through the regulating valve ( 228 ) and enters the inlet ( 218 ) when the fluid pump ( 220 ) is in operation.

1 . An internal combustion engine, comprising: 
 a fluid pump having a pump inlet, a low pressure pump outlet, and a high pressure pump outlet;    a reservoir connected to the high pressure pump outlet;    an oil sump in fluid communication with the pump inlet;    a pressure regulating valve disposed between the high pressure pump outlet and the low pressure pump outlet;    a recirculation passage fluidly connecting the low pressure pump outlet and the pump inlet;    wherein a flow of high pressure oil in the high pressure outlet bypasses through the regulating valve and enters the pump inlet when the pump is in operation.    
     
     
         2 . The internal combustion engine of  claim 1  further comprising a first check valve disposed in the recirculation passage.  
     
     
         3 . The internal combustion engine of  claim 1 , further comprising a vent passage that includes a valve, wherein the vent passage fluidly connects the recirculation passage with the oil sump.  
     
     
         4 . The internal combustion engine of  claim 3 , further comprising an additional vent passage that includes a pressure relief valve, wherein the additional vent passage fluidly connects the recirculation passage with the oil sump.  
     
     
         5 . The internal combustion engine of  claim 1 , further comprising an oil cooler disposed in the recirculation passage.  
     
     
         6 . The internal combustion engine of  claim 1 , further comprising: 
 an oil temperature sensor disposed in the recirculation passage;    an electronic engine controller connected to the recirculation passage; and    an electronic valve connected to the electronic engine controller;    wherein the electronic valve fluidly connects the recirculation passage with the oil sump when a temperature of oil in the recirculation passage exceeds a predetermined value.    
     
     
         7 . The internal combustion engine of  claim 1 , further comprising a third check valve disposed in fluid communication with the pump inlet to prevent backflow from the pump inlet to an oil distribution circuit.  
     
     
         8 . The internal combustion engine of  claim 1 , further comprising a low pressure pump disposed in series between the fluid pump and the oil sump.  
     
     
         9 . The internal combustion engine of  claim 1 , further comprising a core engine structure, wherein the core engine structure is arranged and constructed to provide power that drives the fluid pump.  
     
     
         10 . A fluid pump, comprising: 
 a pump housing;    an injection pressure regulator (IPR) valve disposed on the housing;    a fluid inlet, a high pressure outlet, and a low pressure outlet, formed in the pump housing;    a first check valve integrated in the pump housing and in fluid communication with the low pressure outlet;    a second check valve integrated in the pump housing and in fluid communication with an outlet of the first check valve and the fluid inlet;    wherein when the first check valve is open, the fluid inlet receives an oil flow from the low pressure outlet of the pump.    
     
     
         11 . The fluid pump of  claim 10 , wherein the fluid pump is disposed in a high pressure oil system of an internal combustion engine.  
     
     
         12 . The fluid pump of  claim 10 , wherein at least one of the first check valve and the second check valve includes a bore formed in the housing of the pump.  
     
     
         13 . The fluid pump of  claim 12 , wherein the bore includes a spring and a valve element.  
     
     
         14 . The fluid pump of  claim 10 , further comprising a crankshaft, wherein the crankshaft rotates and is arranged to receive power from at least one of a mechanical geared connection to a core engine structure and an electric motor.  
     
     
         15 . The fluid pump of  claim 14 , wherein the low pressure output of the pump includes an annulus, and wherein the annulus is disposed adjacent to an interface between the crankshaft and the housing of the pump.  
     
     
         16 . A method for a pumping oil in an internal combustion engine comprising the steps of: 
 ingesting an oil flow at a low pressure into an inlet of a fluid pump;    compressing the oil flow to a high pressure;    sending a first portion of the oil flow to a high pressure reservoir;    venting a second portion of the oil flow to a low pressure outlet;    recirculating the from the low pressure outlet to the inlet of the fluid pump through a recirculation path;    mixing the second portion with the inlet oil flow.    
     
     
         17 . The method of  claim 16 , further comprising the step of selectively venting oil from the recirculation path into an oil sump.  
     
     
         18 . The method of  claim 16 , further comprising the step of cooling the oil quantity in the recirculation path.  
     
     
         19 . The method of  claim 16 , further comprising the steps of: 
 sensing a temperature of the oil quantity in the recirculation path; and    opening a vent valve to fluidly connect the recirculation path with an oil sump when the temperature of the oil quantity exceeds a predetermined value.    
     
     
         20 . The method of  claim 16 , wherein the step of compressing is accomplished by use of a power input to the fluid pump from the internal combustion engine.