ENGINE WITH ELECTRONICALLY CONTROLLED PISTON COOLING JETS AND METHOD FOR CONTROLLING THE SAME

Abstract

An engine oil system for an internal combustion engine comprises an electronic control module, an engine oil sump, an engine oil pump, an engine oil gallery, an engine oil pressure sensor, a solenoid control valve, and at least one oil receiving component. The engine oil pump is in fluid communication with the engine oil sump. The engine oil gallery is in fluid communication with at least one engine bearing and a turbocharger. The engine oil pressure sensor and at least one oil receiving component are in fluid communication with the oil gallery. The oil pressure sensor generates an output signal that is transmitted to the electronic control module. The solenoid control valve is in fluid communication with the engine oil gallery and electronic communication with the electronic control module. The solenoid control valve is moveable between at least an open position and a closed position.

Description

TECHNICAL FIELD

The present disclosure relates to engine having electronically controlled piston cooling jets, and more particularly to electronically controlled piston cooling jets that may be selectively operated based on engine operating conditions and an electronic control module to control the piston cooling jets.

BACKGROUND

Many modern diesel engines contain piston cooling jets that spray engine oil on an underside of a piston to provide cooling to the piston. Engine oil, sometimes also referred to as engine lubrication oil or engine lube oil, is continuously fed from an oil rail, or oil gallery to engine parts needing lubrication. For example, it is typically necessary to lubricate parts such as crank shaft and connecting rod bearings, turbochargers, and, in some engines, piston cooling jets. An oil system as described above requires a large oil pump in order to provide the required oil flow rates. Additionally, minimum engine oil pressure recommended for turbochargers from various turbocharger manufacturers are often set at about twenty pounds per square inch (20 psi), a level that may not be met when engine oil is at operating temperature and the engine is operating at low engine speeds, or if the engine is operating at lower engine speeds and the engine components are worn.

SUMMARY

According to one embodiment, an engine oil system for an internal combustion engine comprises an electronic control module, an engine oil sump, an engine oil pump, an engine oil gallery, an engine oil pressure sensor, a solenoid control valve, and at least one oil receiving component. The engine oil pump is disposed in fluid communication with the engine oil sump. The engine oil gallery is disposed in fluid communication with at least one engine bearing and a turbocharger. The engine oil pressure sensor is disposed in fluid communication with the oil gallery. The oil pressure sensor generates an output signal that is transmitted to the electronic control module. The solenoid control valve is disposed in fluid communication with the engine oil gallery and electronic communication with the electronic control module. The solenoid control valve is moveable between at least an open position and a closed position in response to at least an output signal received from the electronic control module. The at least one oil receiving component is disposed in fluid communication with the engine oil gallery.

According to another embodiment, an electronically controllable piston cooling jet system for an internal combustion engine having an electronic control module and at least one piston is provided. The piston cooling jet system comprises at least one piston cooling jet, a pressure sensor, and a solenoid control valve. The piston cooling jet provides oil to the at least one piston. The pressure sensor is in fluid communication with an oil supply to the at least one piston cooling jet. The pressure sensor generates an output signal indicative of fluid pressure within the oil supply. The solenoid control valve has an open position and a closed position. The electronic control module operatively controls the solenoid control valve to the open position and the closed position based upon the output of the oil pressure sensor.

According to one process, a method of controlling an electronically controllable oil receiving subsystem of an engine is provided. The engine has an electronic control module, at least one piston, an oil pressure sensor, a solenoid control valve moveable between at least an open position and a closed position, and at least one oil receiving component. One aspect of the method generates an output signal of the oil pressure sensor indicative of engine oil pressure. The output of the oil pressure sensor is transmitted to the electronic control module. The oil pressure indicated by the output signal of the oil pressure sensor is compared to at least a first predetermined value stored in a memory of the electronic control module. An actuation signal transmits to the solenoid control valve contains at least an instruction to position the solenoid control valve in the open position when the output signal of the oil pressure sensor is indicative of an oil pressure greater than the at least a first predetermined value stored in the memory of the electronic control module. Oil flow is provided to the at least one oil receiving component when the solenoid control valve is in the open position.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram showing a portion of the engine oil system for an engine having electronically controlled oil receiving components.

DETAILED DESCRIPTION

FIG. 1 shows a portion of an engine oil system 10 for a diesel engine. The engine oil system comprises an engine oil sump 12 adapted to hold engine oil that is not presently circulating to other portions of the engine, and is also adapted to collect a majority of the engine oil when the engine is off. An oil pump 14 draws engine oil out of the engine oil sump 12 and provides a force on the engine oil to circulate the oil throughout the rest of the engine oil system 10. An engine oil cooler 16 may also be provided in the engine oil system. The engine oil cooler 16 reduces the temperature of the circulating engine oil.

The engine oil system 10 additionally has an oil filter 18 that removes certain contaminates within the engine oil to prevent damage to the engine. Filtered engine oil is provided to an oil gallery 20. The engine oil gallery 20 has a pressure regulating valve 22 adapted to prevent engine oil pressure from exceeding a predefined threshold. Excessively high engine oil pressure may cause damage to the engine, therefore, the pressure regulating valve allows some oil within the oil gallery 20 to be returned to the engine oil sump 12, thus, reducing the oil pressure within the engine oil gallery 20. The engine oil gallery 20 is adapted to deliver oil to engine bearings and other engine components 24 that require engine oil. The engine bearings and other engine components 24 that require engine oil are in fluid communication with the engine oil sump 12, such that engine oil drains from the engine bearings and other engine components 24 to the engine oil sump 12.

The engine oil gallery 20 additionally provides engine oil to the turbocharger 26. The turbocharger 26 typically receives engine oil from the oil gallery 20 via an oil supply line (not shown) and is not directly connected to the engine oil gallery 20. The engine oil provides lubrication to at least one bearing within the turbocharger 26. Oil that is provided to the turbocharger 26 also drains back to the engine oil sump 12, typically via an oil return line (not shown).

As shown in FIG. 1, the oil gallery 20 is in fluid communication with a solenoid control valve 28. The solenoid control valve 28 controls flow of engine oil to oil receiving components 30, shown in the form of piston cooling jets in FIG. 1 that provide engine oil to a non-combustion face side of engine pistons to reduce the temperature of the pistons. It is contemplated that each piston will have at least one piston cooling jet, and each piston may have a plurality of piston cooling jets. The solenoid control valve 28 is controlled by an engine electronic control module 32 (ECM). The ECM 32 receives information regarding the oil pressure from a pressure sensor 34. The pressure sensor 34 may be located in fluid communication with the oil gallery 20, or elsewhere along the engine oil system 10. The pressure sensor 34 generates an output signal indicative of the oil pressure within the engine oil system 10. The output signal of the pressure sensor 34 may be used to derive the oil pressure, or may be a representation of the oil pressure. Based upon the information provided by the pressure sensor 34, the ECM 32 operates the solenoid control valve 28.

For example, when the pressure sensor 34 and the ECM 32 detect oil pressure below a first oil pressure threshold stored in a memory of the ECM 32, the ECM 32 causes the solenoid control valve 28 to close, stopping the flow of oil to the oil receiving components 30, such as piston cooling jets.

Similarly, when the pressure sensor 34 and the ECM 32 detect oil pressure above a second oil pressure threshold stored in a memory of the ECM 32, the ECM 32 causes the solenoid control valve 28 to open, allowing oil to flow to the oil receiving components 30 such as piston cooling jets. The first threshold and the second threshold may be generally equal, or the first threshold may be a lower oil pressure than the second threshold oil pressure. Therefore, certain operating conditions may exist when the engine oil pressure is above the first threshold oil pressure while the solenoid control valve 28 remains closed, and no oil flows to the oil receiving components.

Therefore, the use of a solenoid control valve 28 to control oil flow to the oil receiving components 30, such as piston cooling jets or other non-lubricating oil receiving components, may be used to help ensure that minimum oil pressure required for the turbocharger 26 may be maintained even in operating conditions historically known to produce low oil pressure, such as low engine speeds while the engine oil is warm.

In addition to increasing the oil pressure, the use of a solenoid control valve 28 to control oil flow to the oil receiving components 30, such as piston cooling jets, may also allow a lower volume oil pump 14 to be used. A lower volume oil pump may be used as engine oil will not flow through the solenoid control valve 28 to the oil receiving components 30 if oil pressure falls below the first oil pressure threshold, therefore, a lower volume pump may be utilized to achieve minimum oil pressure required for normal engine operation. The use of a lower volume oil pump 14 may also reduce a parasitic load on the engine from the oil pump 14, thus, increasing the fuel economy of the engine.

The solenoid control valve 28 to control oil flow to oil receiving components 30 may additionally be utilized to enhance oil warm up from cold starts. For instance, the ECM 32 may cause the solenoid control valve 28 to open when the engine is first started such that the oil flowing through the oil receiving components 30, such as piston cooling jets, is heated by the pistons, reducing the time required for the engine oil to reach normal operating temperatures.

Additionally, the engine oil system 10 may increase the oil change interval for the engine oil by decreasing work to the oil by using the solenoid control valve 28 to control the flow of oil to oil receiving components 30. Increased oil change intervals allow a vehicle having an engine with the engine oil system 10 to be in use for longer periods of time between servicing, potentially increasing the productivity of the vehicle.

While specific embodiments have been illustrated and described, numerous modifications come to mind without significantly departing from the spirit of the invention, and the scope of protection is only limited by the scope of the accompanying Claims.

Claims

1. An engine oil system for an internal combustion engine comprising:

an electronic control module:

an engine oil sump;

an engine oil pump disposed in fluid communication with the engine oil sump;

an engine oil gallery disposed in fluid communication with at least one engine bearing and a turbocharger;

an engine oil pressure sensor disposed in fluid communication with the engine oil gallery, the oil pressure sensor provided for generating an output signal to be transmitted to the electronic control module;

a solenoid control valve disposed in fluid communication with the engine oil gallery and in electrical communication with the engine control module, the solenoid control valve being moveable between at least an open position and a closed position in response to at least an output signal received from the engine control module; and

at least one oil receiving component in fluid communication with the solenoid control valve.

2. The engine oil system of claim 1, wherein the solenoid control valve is moved to the closed position when the output signal of the oil pressure sensor indicates engine oil pressure is below a first threshold.

3. The engine oil system of claim 1 further comprising an oil cooler.

4. The engine oil system of claim 1 further comprising an oil filter.

5. The engine oil system of claim 1 further comprising an engine oil gallery pressure regulating valve disposed in fluid communication with the engine oil gallery and the engine oil sump, the oil gallery pressure regulating valve being moveable between at least an open position and a closed position.

6. The engine oil system of claim 5, wherein when oil pressure within the engine oil gallery is above a predetermined pressure threshold, the engine oil gallery pressure regulating valve moves to the open position and allows oil to flow from the engine oil gallery to the engine oil sump.

7. The engine oil system of claim 1, wherein the at least one oil receiving component comprises a piston cooling jet.

8. An electronically controllable piston cooling jet system for an internal combustion engine having an electronic control module and at least one piston, the piston cooling jet system comprising:

at least one piston cooling jet providing oil to the at least one piston;

a pressure sensor in fluid communication with an oil supply to the at least one piston cooling jet, the pressure sensor provided for generating an output signal indicative of fluid pressure within the oil supply; and

a solenoid control valve having an open position and a closed position,

wherein the electronic control module operatively controls the solenoid control valve to the open position and the closed position based upon the output of the oil pressure sensor.

9. The electronically controllable piston cooling jet system of claim 8, wherein the solenoid control valve is in the closed position when the output of the oil pressure sensor indicates engine oil pressure below a first threshold.

10. The electronically controllable piston cooling jet system of claim 9, wherein the solenoid control valve is in the closed position when the output of the oil pressure sensor indicates engine oil pressure above a second threshold.

11. The electronically controllable piston cooling jet system of claim 10, wherein the first threshold is lower than the second threshold.

12. The electronically controllable piston cooling jet system of claim 8, wherein the engine has a plurality of pistons and each piston has at least one piston cooling jet.

13. A method of controlling an electronically controllable oil receiving subsystem for an engine, the engine having an electronic control module, at least one piston, an oil pressure sensor, a solenoid control valve movable between at least an open position and a closed position, and at least one oil receiving component, the method comprising:

generating an output signal indicative of the oil pressure sensor indicative of engine oil pressure;

transmitting the output signal of the oil pressure sensor to the electronic control module;

comparing oil pressure indicated by the output signal of the oil pressure sensor to at least a first predetermined value stored in a memory of the electronic control module;

transmitting an activation signal to the solenoid control valve, the activation signal containing at least an instruction to position the solenoid control valve in the open position when the output of the oil pressure sensor is greater than the at least a first predetermined value stored in the memory of the electronic control module; and

providing oil flow to the at least one oil receiving component when the solenoid control valve is in the open position.

14. The method of claim 13 further comprising:

comparing the output of the oil pressure sensor to a second predetermined value stored in a memory of the electronic control module, the second predetermined value being less than the first predetermined value;

controlling the solenoid control valve to the closed position when the output of the oil pressure sensor is less than the second predetermined value stored in the memory of the electronic control module; and

preventing oil flow to the at least one oil receiving component when the solenoid control valve is in the closed position.

15. The method of claim 14, wherein the first predetermined value and the second predetermined value are equal.

16. The method of claim 14, wherein the first predetermined value is larger than the second predetermined value.

17. The method of claim 13 further comprising:

monitoring engine temperature information with the electronic control module;

controlling the solenoid control valve to the open position when the monitoring of the engine temperature indicates the engine temperature is lower than a first predetermined engine temperature stored in the memory of the electronic control module; and

providing oil flow to the at least one oil receiving component when the solenoid control valve is in the open position.

18. The method of claim 13, wherein the oil receiving component comprises a piston cooling jet.