Pump assembly and method
OwnerRobert H. Breedeninventor
Life of this patent
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Abstract
A pump assembly and method for an internal combustion engine includes a high-pressure pump for pressurizing oil used to actuate fuel injectors or other devices, a hydraulic inlet throttle valve, a three-way valve for alternatively connecting the inlet throttle valve to output pressure or to the sump and a solenoid responsive to signals from an electronic control module for shifting the three-way valve.
Claims39
A pump assembly for an internal combustion engine of the type having one or more devices actuated by high-pressure liquid, an outlet passage connected to the one or more devices, a source of liquid, and an ECM;
- the pump assembly comprising a variable output high-pressure pump having a pump inlet port, and a pump outlet port connected to the outlet passage;
- a hydraulic inlet throttle valve having an inlet throttle valve inlet port connected to the source, an inlet throttle valve outlet port connected to the pump inlet port, a first spool moveable between an open position and a closed position, a spring biasing the first spool toward the open position, such spool including an inlet throttle valve piston forming one wall of a hydraulic chamber wherein the pressure of liquid in the chamber biases the first spool toward the closed position;
- a three-way valve having a three-way valve inlet port connected to the outlet passage, a three-way valve drain port connected to the source, a work port connected to the hydraulic chamber of the inlet throttle valve, and a second spool moveable between a first position in which the work port is connected to the drain port, a null position in which the work port is closed or substantially closed, and a second position in which the work port is connected to the three-way valve inlet port;
- and first means for shifting the second spool toward the first position when the pressure in the outlet passage is less than the desired pressure in the outlet passage, for maintaining the three-way valve spool in the null position when the pressure in the outlet passage is equal to the desired pressure in the outlet passage, and for shifting the three-way valve spool toward the second position when the pressure in the outlet passage is greater than the desired pressure in the outlet passage.
A pump assembly for an internal combustion engine of the type having one or more devices actuated by high-pressure liquid, an outlet passage connected to the one or more devices, a source of liquid, and an ECM;
- the pump assembly comprising a variable output high-pressure pump having a pump inlet port, and a pump outlet port connected to the outlet passage;
- a hydraulic inlet throttle valve having an inlet throttle valve inlet port connected to the source, an inlet throttle valve outlet port connected to the pump inlet port, an inlet throttle valve spool moveable between an open position and a closed position, a first spring biasing the inlet throttle valve spool toward one of said positions, such spool including an inlet throttle valve piston forming one wall of a hydraulic chamber wherein the pressure of liquid in the chamber biases the spool toward the other of said positions;
- a three-way valve having a three-way valve inlet port connected to the outlet passage, a three-way valve drain port connected to the source, a work port connected to the hydraulic chamber of the inlet throttle valve, and a three-way valve spool moveable between a first position in which the work port is connected to the drain port and a second position in which the work port is connected to the three-way valve inlet port;
- and means for shifting the three-way valve spool toward the first position when the pressure in the outlet passage is less than the desired pressure in the outlet passage and for shifting the three-way valve spool toward the second position when the pressure in the outlet passage is greater than the desired pressure in the outlet passage.
The method of controlling the pressure of an actuating liquid in an internal combustion engine having one or more hydraulically actuated devices, a high-pressure pump for supplying liquid at output pressure to the one or more hydraulically actuated devices, a source of low-pressure liquid, a hydraulic inlet throttle valve for supplying liquid from the source to the pump, the inlet throttle valve having an inlet throttle valve spool with a piston facing a hydraulic chamber so that the pressure of liquid in the chamber biases the spool toward a closed position, and a spring biasing the inlet throttle valve spool toward an open position, comprising the steps of:
- a) connecting the hydraulic chamber directly to the source when the actual outlet pressure of the pump is less than the desired outlet pressure so that the spring shifts the inlet throttle valve spool toward the open position and liquid in the hydraulic chamber drains directly to the source to increase inlet flow of liquid to the pump and increase outlet pressure;
- b) connecting the hydraulic chamber directly to the output of the pump when the actual outlet pressure is greater than the desired outlet pressure so that liquid in the hydraulic chamber at outlet pressure shifts the spool toward the closed position to decrease inlet flow of liquid to the pump and decrease outlet pressure;
- and
- c) preventing or substantially preventing flow of liquid to or from the hydraulic chamber when the actual outlet pressure is equal to the desired outlet pressure so that the position of the inlet throttle valve is maintained.
Dependencies are inferred from the claim text.