Variable displacement engine control

Patent metadata

Field	Value
Publication number	US-9677479-B2
Application number	US-201414445919-A
Country	US
Kind code	B2
Filing date	Jul 29, 2014
Priority date	Jul 29, 2014
Publication date	Jun 13, 2017
Grant date	Jun 13, 2017

Abstract

Methods and systems are provided for controlling engine operation. One method comprises during a first condition, operating the engine with a single cylinder deactivated and remaining cylinders activated with a first intake duration, and during a second condition, operating the engine with the single cylinder deactivated and the remaining cylinders activated with a second intake duration. The method further comprises during a third condition, operating the engine with all cylinders activated.

First claim

The invention claimed is:

1. A method for an engine comprising:
during a first condition that includes a first engine load, via a controller operating the engine with a single cylinder deactivated by a deactivation mechanism and remaining cylinders activated with a first intake duration;
during a second condition that includes a second engine load lower than the first engine load, via the controller operating the engine with the single cylinder deactivated and the remaining cylinders activated with a second intake duration; and
during a third condition that includes a third engine load higher than the first engine load, via the controller operating the engine with all cylinders activated.

2. The method of claim 1 , further comprising during the first condition operating the remaining cylinders with a first intake valve lift, and during the second condition, operating the remaining cylinders with a second intake valve lift.

3. The method of claim 2 , wherein during the third condition, all cylinders are activated with the first intake duration and the first intake valve lift.

4. The method of claim 3 , wherein the first intake valve lift is higher than the second intake valve lift.

5. The method of claim 3 , wherein the first intake duration is longer than the second intake duration.

6. The method of claim 5 , wherein the first intake duration is approximately 240 crank angle degrees, and wherein the second intake duration is approximately 120 crank angle degrees.

7. The method of claim 1 , wherein an exhaust duration is identical during all three conditions.

8. The method of claim 7 , wherein the exhaust duration is approximately 260 crank angle degrees.

9. The method of claim 1 , wherein the second condition includes an idling engine condition.

10. The method of claim 1 , further comprising switching between the first condition and the second condition with a cam profile switching system between a first cam and a second cam, the first cam for opening a first intake valve of each of the remaining cylinders for the first intake duration, and the second cam for opening the first intake valve of each of the remaining cylinders for the second intake duration.

11. The method of claim 1 , wherein the engine comprises four cylinders arranged inline.

12. The method of claim 11 , wherein during the first and second conditions, firing events in the engine are separated by 240 crank angle degrees.

13. The method of claim 11 , wherein during the third condition, the single cylinder is fired approximately midway between a fourth cylinder and a third cylinder, and wherein the fourth cylinder and the third cylinder are fired 240 crank angle degrees apart.

14. The method of claim 13 , further comprising firing a second cylinder approximately 240 crank angle degrees after firing the third cylinder.

15. An engine with four cylinders, comprising:
a single cylinder of the four cylinders including a deactivation mechanism;
three cylinders other than the single cylinder, each with at least one intake valve actuatable between an open position and a closed position via a first intake cam having a first profile for opening the intake valve for a first intake duration and via a second intake cam having a second profile for opening the intake valve for a second intake duration; and
a controller with computer-readable instructions stored in non-transitory memory for:
during a low engine load,
deactivating the single cylinder; and
actuating the intake valve of each of the three cylinders with the second intake cam;

during a medium engine load,
deactivating the single cylinder; and
actuating the intake valve of each of the three cylinders with the first intake cam; and

during a high engine load,
activating the single cylinder; and
actuating the intake valve of each of the three cylinders with the first intake cam.

16. The engine of claim 15 , wherein the first intake duration is longer than the second intake duration.

17. The engine of claim 15 , wherein the first profile of the first intake cam has a first valve lift and the second profile of the second intake cam has a second valve lift.

18. The engine of claim 17 , wherein the first valve lift is higher than the second valve lift.

19. A system, comprising:
an engine including four cylinders arranged inline, each cylinder having at least one intake valve, the intake valve of a single cylinder being actuated by a first cam that has a non-zero lift profile and a second cam that has a zero lift profile, and each of the intake valves of remaining three cylinders being actuated by one of two cams, where both cams have non-zero lift profiles; and
a controller with computer-readable instructions stored in non-transitory memory for:
during a low engine load, deactivating the single cylinder through the second cam, and actuating the intake valve of each of the remaining three cylinders with a first duration lift cam of the two cams;
during a medium engine load, deactivating the single cylinder through the second cam, and actuating the intake valve of each of the remaining three cylinders with a second duration lift cam of the two cams, the second duration lift cam open for a longer duration than the first duration lift cam; and
during a high engine load, activating the single cylinder through the first cam, and actuating the intake valve of each of the remaining three cylinders with the second duration lift cam.

Assignees

• Ford Global Tech Llc

Inventors

• Boyer Brad Alan
• Mcconville Gregory Patrick
• Ervin James Douglas
• Ku Kim Hwe

Classifications

• F02D13/06

  Cutting-out cylinders · CPC title

• F02B2075/1816

  four · CPC title

• F02B75/20

  with cylinders all in one line · CPC title

• F02D13/0226

  changing valve lift or valve lift and timing · CPC title

• F02D17/02 Primary

  Cutting-out (cutting-out engines in multiple engine arrangements F02D25/04) · CPC title