Maintaining oil pressure during cylinder deactivation operation

Patent metadata

Field	Value
Publication number	US-12264604-B2
Application number	US-202217884546-A
Country	US
Kind code	B2
Filing date	Aug 9, 2022
Priority date	Feb 21, 2020
Publication date	Apr 1, 2025
Grant date	Apr 1, 2025

Abstract

Systems, devices, and methods are disclosed that during cylinder deactivation, including skipfire, at low engines speeds and low engine loads maintain adequate oil pressure of valvetrain components or hardware required for CDA and/or skipfire operation.

First claim

What is claimed i:

1. An oil lube system for an internal combustion engine, comprising:
an oil pump fluidly connected to an oil source, wherein the oil pump is operable to output a flow of oil under pressure;
a cylinder block fluidly connected to the oil pump to receive a first part of the flow of oil;
a cylinder head fluidly connected to the oil pump to receive a second part of the flow of oil, wherein the second part of the flow of oil bypasses the cylinder block to flow directly to the cylinder head; and
a valvetrain fluidly connected to receive a portion of the second part of the flow of oil from the cylinder head, wherein the valvetrain is configured to deactivate or skipfire one or more cylinders of the cylinder block.

2. The system of claim 1 , further comprising:
an oil cooler and an oil filter in a flow path between the oil pump and the cylinder block, and wherein the second part of the flow of oil bypasses at least one of the oil cooler and the oil filter.

3. The system of claim 1 , wherein the cylinder head is fluidly isolated from the cylinder block.

4. An oil lube system for an internal combustion engine, comprising:
an oil pump fluidly connected to an oil source, wherein the oil pump is operable to output a flow of oil under pressure;
a cylinder block fluidly connected to the oil pump to receive the flow of oil;
a cylinder head fluidly connected to receive a first part of the flow of oil from the cylinder block; and
a valvetrain fluidly connected to receive a second part of the flow of oil from the cylinder head, wherein the second part of the flow of oil bypasses the cylinder block to flow directly to the cylinder head, wherein the valvetrain is configured to deactivate or skipfire one or more cylinders of the cylinder block, and wherein at least one of the valvetrain and the cylinder block includes one or more components that are replaced with bearings having reduced lubrication requirements.

5. The system of claim 4 , wherein the one or more replaced components include camshaft bearings of the valvetrain.

6. An oil lube system for an internal combustion engine, comprising:
an electric oil pump fluidly connected to an oil source, wherein the electric oil pump is operable to output a flow of oil under pressure independently of a speed of the internal combustion engine;
a cylinder block fluidly connected to the oil pump to receive the flow of oil;
a cylinder head fluidly connected to receive a first part of the flow of oil from the cylinder block; and
a valvetrain fluidly connected to receive a second part of the flow of oil from the cylinder head, wherein the second part of the flow of oil bypasses the cylinder block to flow directly to the cylinder head, wherein the valvetrain is configured to deactivate or skipfire one or more cylinders of the cylinder block.

7. An oil lube system for an internal combustion engine, comprising:
a variable flow oil pump fluidly connected to an oil source, wherein the variable flow oil pump is operable to output a flow of oil under pressure, wherein a displacement of the variable flow oil pump is increased at engine speeds lower than a first speed threshold and the displacement is decreased at engine speeds above a second speed threshold;
a cylinder block fluidly connected to the oil pump to receive the flow of oil;
a cylinder head fluidly connected to receive a first part of the flow of oil from the cylinder block; and
a valvetrain fluidly connected to receive a second part of the flow of oil from the cylinder head, wherein the second part of the flow of oil bypasses the cylinder block to flow directly to the cylinder head, wherein the valvetrain is configured to deactivate or skipfire one or more cylinders of the cylinder block.

8. The system of claim 7 , wherein the displacement of the variable flow oil pump is controlled in response to a number of cylinders that are firing.

9. The system of claim 7 , wherein the displacement of the variable flow oil pump is controlled in response to a target output oil pressure.

10. The system of claim 9 , wherein the target output oil pressure is based on a number of cylinders that are firing.

11. An oil lube system for an internal combustion engine, comprising:
an oil pump fluidly connected to an oil source, wherein the oil pump is operable to output a flow of oil under pressure;
a cylinder block fluidly connected to the oil pump to receive the flow of oil;
a cylinder head fluidly connected to receive a first part of the flow of oil from the cylinder block, wherein the cylinder block includes a number of piston cooling nozzles, and at least one of the number of piston cooling nozzles includes a flow control valve to reduce an oil flow through the piston cooling nozzle in response to an oil pressure that is below a threshold; and
a valvetrain fluidly connected to receive a second part of the flow of oil from the cylinder head, wherein the second part of the flow of oil bypasses the cylinder block to flow directly to the cylinder head, wherein the valvetrain is configured to deactivate or skipfire one or more cylinders of the cylinder block.

12. The system of claim 11 , wherein the oil pressure varies directly with a speed of the internal combustion engine.

13. An oil lube system for an internal combustion engine, comprising:
an oil pump fluidly connected to an oil source, wherein the oil pump is operable to output a flow of oil under pressure;
a cylinder block fluidly connected to the oil pump to receive the flow of oil;
a cylinder head fluidly connected to receive a first part of the flow of oil from the cylinder block, wherein the cylinder block includes a number of piston cooling nozzles, and at least one of the number of piston cooling nozzles includes a flow control valve operable to reduce an oil flow through the piston cooling nozzle in response to an oil pressure that is below a threshold; and
a valvetrain fluidly connected to receive a second part of the flow of oil from the cylinder head, wherein the second part of the flow of oil bypasses the cylinder block to flow directly to the cylinder head, wherein the valvetrain is configured to deactivate or skipfire one or more cylinders of the cylinder block.

14. The system of claim 13 , wherein the flow control valve is operable to shut off oil flow through the piston cooling nozzle.

15. The system of claim 13 , wherein each of the piston cooling nozzles includes a flow control valve, and the oil flow from each piston cooling nozzle is shut off in response to cylinder deactivation or skipfire during a low engine speed/load condition.

16. The system of claim 13 , wherein each of the piston cooling nozzles includes a flow control valve, and an average oil flow from each piston cooling nozzle is reduced by the respective flow control valve in response to cylinder deactivation or skipfire during a low engine speed/load condition.

17. The system of claim 13 , wherein the flow control valve is operable to divert oil flow from the piston cooling nozzle to the valvetrain in response to cylinder deactivation or skipfire during a low engine speed/load condition.

18. An oil lube system for an internal combustion engine, comprising:
an oil pump fluidly connected to an oil source, wherein the oil pump is operable to output a flow of oil under pressure independently of a speed of the internal combustion engine;
a cylinder block fluidly connected to the oil pump to receive the flow of oil;
a cylinder head fluidly connected to receive a first part of the flow of oil from the cylinder block;
a valvetrain

Assignees

• Cummins Inc

Inventors

• Kothandaraman Govindarajan
• Kocher Lyle E
• Barnes David M
• Bardakjy Scott Robert
• Kolhouse J Steven

Classifications

• F01P2003/006

  the liquid being oil · CPC title

• F01P3/06

  Arrangements for cooling pistons · CPC title

• F01M2001/0261

  driven by the camshaft · CPC title

• F01M2001/0215

  Electrical pumps · CPC title

• F01M5/002

  Cooling · CPC title