Engine oil supply system and a method of controlling an engine oil supply system

Patent metadata

Field	Value
Publication number	US-9435235-B2
Application number	US-201414268692-A
Country	US
Kind code	B2
Filing date	May 2, 2014
Priority date	Jun 4, 2013
Publication date	Sep 6, 2016
Grant date	Sep 6, 2016

Abstract

An engine oil supply system for a motor vehicle and a method of controlling an engine oil supply system of a motor vehicle is disclosed in which, particularly during an engine overrun period or an engine shut-down, kinetic energy from the slowing engine is used to drive an oil pump so as to store oil in an oil accumulator for later use by one or more engine components without the engine using fuel. The stored oil allows a downsized oil pump to be used thereby saving fuel by providing a supply of oil in addition to or as an alternative to the oil supplied from the oil pump.

First claim

The invention claimed is:

1. An engine oil supply system having an engine driven oil pump to provide a supply of oil at pressure to an oil supply circuit and an oil accumulator connectable to the oil supply circuit by means of an electronically controlled valve, an electronic controller arranged to receive an input indicative of at least one engine operating condition and to control operation of the electronically controlled valve based at least partly upon the at least one engine operating condition, a first pressure sensor to sense a pressure of oil in the oil supply circuit and supply an output indicative of the sensed pressure to the electronic controller and a second oil pressure sensor to sense a pressure of the oil in the oil accumulator and supply an output indicative of the sensed pressure to the electronic controller, wherein the electronic controller is operable to compare the output from the first pressure sensor with the output from the second pressure sensor and, if the sensed pressure of the oil in the oil accumulator is lower than the sensed pressure of the oil in the oil supply circuit and a predefined engine operating condition indicating that charging of the oil accumulator with oil will incur substantially no fuel usage by the engine is present, operate the electronically controlled valve to connect the oil accumulator to the oil supply circuit so as to charge the oil accumulator with oil at pressure, where the electronically controlled valve is formed as an integral part of an outlet from the engine driven oil pump.

2. The system as claimed in claim 1 , wherein the predefined engine operating condition indicating that charging of the oil accumulator with oil will incur substantially no fuel usage by the engine is an engine shut-down condition.

3. The system as claimed in claim 1 , wherein the predefined engine operating condition indicating that charging of the oil accumulator with oil will incur substantially no fuel usage by the engine is an engine over-run condition.

4. The system as claimed in claim 1 , wherein the predefined engine operating condition indicating that charging of the oil accumulator with oil will incur substantially no fuel usage by the engine is an engine operating condition in which the engine is operating at a speed where excess oil would otherwise be vented to an oil reservoir.

5. The system as claimed in claim 1 , wherein the first pressure sensor is located in the oil supply circuit between the outlet from the engine driven pump and the electronically controlled valve.

6. The system as claimed in claim 1 , wherein the second pressure sensor is located so as to sense the pressure of the oil substantially at a take-off point where the oil is extracted from the oil supply circuit for charging the oil accumulator.

7. The system as claimed in claim 6 , wherein the second pressure sensor is located at one of a position in a supply line joining the electronically controlled valve to the accumulator, an outlet from the electronically controlled valve, an inlet to the oil accumulator and a position on the oil accumulator where the oil pressure within the oil accumulator can be directly sensed.

8. A method of controlling an engine oil supply system having an engine driven oil pump to provide a supply of oil at pressure to an oil supply circuit and an oil accumulator connectable to the oil supply circuit, wherein the method comprises measuring a pressure of the oil in the oil supply circuit, measuring a pressure of the oil in the oil accumulator, comparing the pressure of the oil in the oil supply circuit to the pressure of oil in the oil accumulator and, if the measured pressure of the oil in the oil accumulator is lower than the measured pressure of the oil in the oil supply circuit and a predefined operating condition is present indicating that charging of the oil accumulator with oil will incur substantially no fuel usage by the engine, connecting the oil accumulator to the oil supply circuit so as to charge the oil accumulator with oil at pressure, wherein the predefined operating condition indicating that charging of the oil accumulator with oil will incur substantially no fuel usage by the engine is one of an engine shut-down condition and an engine over-run condition.

9. The method as claimed in claim 8 , wherein the engine oil supply system includes a controllable valve to selectively connect the oil accumulator to the oil supply circuit and connecting the oil accumulator to the oil supply circuit so as to charge the oil accumulator with oil at pressure comprises opening the controllable valve to connect the oil accumulator to the oil supply circuit.

10. A method comprising:
adjusting an electronically controlled valve to a first position to connect an oil accumulator to an oil supply line in response to accumulator pressure being less than an oil supply circuit pressure; and
adjusting the valve to a second position to connect the oil accumulator and an oil supply circuit which supplies oil to a component making a demand for oil in response to the accumulator pressure being greater than a predefined pressure.

11. The method of claim 10 , further comprising:
adjusting the valve to a third position to connect the oil supply line and the oil supply circuit which supplies oil to the component making the demand for oil in response to the accumulator pressure being less than the oil supply circuit pressure or the predefined pressure.

12. The method of claim 10 , wherein adjusting to the first position includes a condition where no fuel usage occurs.

Assignees

• Ford Global Tech Llc

Inventors

• Pegg Ian Graham
• Bowman Timothy James

Classifications

• F01M2005/028

  with a reservoir under pressure · CPC title

• F01M1/16 Primary

  Controlling lubricant pressure or quantity (rendering machines or engines inoperative or idling on lubricant pressure failure F01M1/22) · CPC title

• F01M5/025 Primary

  by prelubricating, e.g. using an accumulator · CPC title

• F01M9/00

  Lubrication means having pertinent characteristics not provided for in, or of interest apart from, groups F01M1/00 - F01M7/00 · CPC title

• F01M2001/0253

  characterised by the pump driving means · CPC title