Method for controlling variable oil pressure to a piston squirter based on piston temperature

Patent metadata

Field	Value
Publication number	US-9989007-B2
Application number	US-201615183117-A
Country	US
Kind code	B2
Filing date	Jun 15, 2016
Priority date	Jun 15, 2016
Publication date	Jun 5, 2018
Grant date	Jun 5, 2018

Abstract

A method for controlling variable oil pressure to a piston squirter based on piston temperature according to an exemplary embodiment includes a temperature estimation module and an oil pump pressure control module. The temperature estimation module estimates a piston temperature associated with a cylinder based on engine operating conditions. The oil pump pressure control module controls the oil pressure level delivered to at least one of piston squirter associated with the cylinder to selectively spray oil on the piston based on temperature estimations.

First claim

What is claimed is:

1. A method comprising:
estimating a piston temperature based on engine coolant temperature and a predetermined offset value when the cylinder is deactivated;
determining if the estimated piston temperature is greater than a predetermined hot temperature threshold; and
controlling an oil pump pressure to at least one piston squirter associated with the cylinder to cause the at least one piston squirter to activate if the estimated piston temperature is greater than the predetermined hot temperature threshold.

2. The method of claim 1 further comprising estimating the piston temperature based on a predetermined thermal inertia of the piston.

3. The method of claim 1 wherein controlling the oil pump pressure further comprises increasing the oil pump pressure to the at least one oil squirter if the estimated piston temperature is greater than the predetermined hot temperature threshold.

4. The method of claim 1 wherein controlling the oil pump pressure further comprises decreasing oil pump pressure to the at least one oil squirter if the estimated piston temperature is less than predetermined hot temperature threshold.

5. The method of claim 1 further comprising estimating a piston temperature based on engine operating conditions including engine speed, engine oil pressure, air per cylinder, and engine coolant temperature.

6. The method of claim 5 further comprising estimating the piston temperature based on high engine oil pressure.

7. The method of claim 5 further comprising estimating the piston temperature based on low engine oil pressure.

8. The method of claim 1 further comprising filtering the piston temperature using a lag filter.

9. The method of claim 8 wherein the lag filter is a first order lag filter.

10. The method of claim 8 further comprising adjusting the lag filter based on at least one of engine speed and an iteration loop rate.

11. The method of claim 10 wherein the piston temperature is adjusted at a first rate that is directly proportional to the at least one of the engine speed and the iteration loop rate.

12. A system comprising:
a temperature estimation module that estimates a piston temperature associated with a cylinder based on engine operating conditions wherein the temperature estimation module estimates the piston temperature of a deactivated cylinder based on engine coolant temperature and a predetermined offset value;
at one piston squirter associated with the cylinder; and
an oil pressure control module that controls pressure to the at least one piston squirter, the oil pressure control module being operable to activate the at least one piston squirter if the estimated piston temperature is greater than a predetermined hot temperature threshold.

13. The system of claim 12 wherein the oil pressure control module increases the oil pump pressure to the at least one oil squirter if the estimated piston temperature is greater than the predetermined hot temperature threshold.

14. The system of claim 12 wherein the oil pressure control module decreases the oil pump pressure to the at least one oil squirter if the estimated piston temperature is less than the predetermined hot temperature threshold.

15. The system of claim 12 wherein the temperature estimation module estimates the piston temperature based on engine operating conditions including engine speed, engine oil pressure, air per cylinder, and engine coolant temperature.

16. The system of claim 12 wherein the temperature estimation module estimates the piston temperature further based on a predetermined thermal inertia of the piston.

17. The system of claim 12 further comprising a temperature filter module that filters the piston temperature using a lag filter.

18. The system of claim 17 wherein the lag filter is a first order lag filter.

Assignees

• Gm Global Tech Operations Llc

Inventors

• Shibata Jonathan T

Classifications

• F02F3/22 Primary

  the fluid being liquid · 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

• F02D2200/02

  the parameters being related to the engine · CPC title

• F02D41/30 Primary

  Controlling fuel injection {(F02D41/182, F02D41/24 take precedence)} · CPC title

• F01M1/08

  Lubricating systems characterised by the provision therein of lubricant jetting means · CPC title