Control system and method for a valve actuator

• US 20050011479A1
• Filed: 07/15/2003
• Published: 01/20/2005
• Est. Priority Date: 07/15/2003
• Status: Active Grant

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Bloms, Jason K., Funke, Steven J., Kagy, Robert A.
• Granted Patent: US 6,976,459 B2
• Time in Patent Office: Days
• US Class Current: 123/90.160
• CPC Class Codes: F01L 1/267 with means for varying the timing or the lift of the valves
• CPC Class Codes: F01L 13/0015 for optimising engine performances by modifying valve lift according to various working parameters, e.g. rotational speed, load, torque
• CPC Class Codes: F01L 2013/0089 with means for delaying valve closing
• CPC Class Codes: F01L 2800/00 Methods of operation using a variable valve timing mechanism
• CPC Class Codes: F01L 9/10 by fluid means, e.g. hydraulic
• CPC Class Codes: F02D 13/0203 Variable control of intake and exhaust valves
• CPC Class Codes: F02D 13/0223 Variable control of the intake valves only
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

A method of controlling an engine having a valve actuation system is provided. The engine is started. A first parameter indicative of a first temperature of the engine is sensed. A second parameter indicative of a second temperature of the engine is sensed. The valve actuation system is disabled to prevent the implementation of a variation on conventional engine valve actuation timing in response to each of the first and second temperatures being below a predetermined value.

Claims

1. A method of controlling an engine having a valve actuator, comprising:

sensing a first parameter indicative of a first temperature of the engine;

sensing a second parameter indicative of a second temperature of the engine;

enabling the valve actuator to implement a variation on conventional engine valve actuation timing in response to one of the first and second temperatures being above a predetermined value; and

limiting an amount of fuel injected into a cylinder of the engine when the other of the first and second temperatures is below a predetermined value.

2. The method of claim 1, further including ceasing to limit the amount of fuel injected into the cylinder of the engine in response to each of the first and second temperatures being above a predetermined value.

3. The method of claim 1, wherein the first temperature is an engine coolant temperature and the second temperature is an intake manifold temperature.

4. The method of claim 3, further including enabling the valve actuator when the engine coolant temperature is above the predetermined value and the intake manifold temperature is below the predetermined value.

5. The method of claim 3, further including disabling the valve actuator when the engine coolant temperature is below the predetermined value.

6. The method of claim 1, wherein the predetermined value is 20°

C.

7. The method of claim 1, further including closing a control valve to enable the valve actuator.

8. The method of claim 3, further including enabling the valve actuator to implement a variation on a conventional engine valve actuation timing and enabling a valve operation detection system to monitor the operation of the valve actuator to determine proper operation of the valve actuator when at least the coolant temperature is above a predetermined value.

9. The method of claim 8, further including limiting an amount of fuel injected into a cylinder of the engine and an amount of torque generated by the engine when the valve actuator is not operating properly.

11. The method of claim 1, further including limiting an amount of torque generated by the engine when one of the first and second temperatures are below the predetermined value.

31. The method of claim 1, further including:

enabling a valve operation detection system to monitor the operation of the valve actuator to determine proper operation of the valve actuator; and

generating a fault condition when both the first and second temperatures are above the predetermined value and the valve operation detection system detects improper operation after having determined proper operation of the valve actuator.

32. The method of claim 1, further including:

enabling a valve operation detection system to monitor the operation of the valve actuator to determine proper operation of the valve actuator; and

ceasing to limit the amount of fuel injected into the cylinder when both the first and second temperatures are above the predetermined value and the valve operation detection system determines proper operation of the valve actuator.

10. (Cancelled).

12. A valve actuation system for an engine having an intake valve moveable between a first position where the intake valve prevents a flow of fluid and a second position where the intake valve allows a flow of fluid, comprising:

a valve actuator adapted to selectively engage the intake valve to prevent the intake valve from returning to the first position;

a first sensor adapted to sense a first parameter indicative of a first temperature of the engine;

a second sensor adapted to sense a second parameter indicative of a second temperature of the engine; and

a controller adapted to engage the valve actuator with the intake valve when one of the first and second temperatures is above a predetermined value and to limit an amount of fuel injected into a cylinder of the engine when the other of the first and second temperatures is below a predetermined value.

13. The system of claim 12, wherein the controller is adapted to cease limiting the amount of fuel injected into the cylinder of the engine when each of the first and second temperatures are above a predetermined value.

14. The system of claim 12, wherein the first sensor is adapted to sense a temperature indicative of the temperature of an engine coolant and the second sensor is adapted to sense a temperature indicative of the temperature of an intake manifold.

15. The system of claim 14, wherein the controller is adapted to enable the valve actuator when the engine coolant temperature is above the predetermined value and the intake manifold temperature is below the predetermined value, and adapted to disable the valve actuator when the engine coolant temperature is below the predetermined value.

16. The system of claim 12, further including a control valve moveable between a first position where the valve actuator is enabled and a second position where the valve actuator is disabled.

17. The system of claim 14, further including a detection system adapted to determine whether the valve actuator is operating properly, wherein the controller is configured to enable the valve actuator to implement a variation on a conventional engine valve actuation timing and to enable the detection system when at least the coolant temperature is above the predetermined value.

33. The valve actuation system of claim 12, wherein the controller is further configured to enable a valve operation detection system to monitor the operation of the valve actuator to determine proper operation of the valve actuator, and to generate a fault condition when both the first and second temperatures are above the predetermined value and the valve operation detection system detects improper operation after having determined proper operation of the valve actuator.

34. The valve actuation system of claim 12, wherein the controller is further configured to enable a valve operation detection system to monitor the operation of the valve actuator to determine proper operation of the valve actuator, and

to cease limiting the amount of fuel injected into the cylinder when both the first and second temperatures are above the predetermined value and the valve operation detection system determines proper operation of the valve actuator.

18. An engine system, comprising,

an engine block defining a cylinder;

a piston slidably disposed within the cylinder, the piston moveable between a top dead center position and a bottom dead center position;

a fuel injection system adapted to inject a quantity of fuel into the cylinder;

an intake valve operatively associated with the cylinder and moveable between a first position where the intake valve prevents fluid from flowing relative to the cylinder and a second position where the fluid is allowed to flow relative to the cylinder;

a valve actuator adapted to selectively engage the intake valve to prevent the intake valve from returning to the first position;

a first sensor adapted to sense a first parameter indicative of a first temperature of the engine;

a second sensor adapted to sense a second parameter indicative of a second temperature of the engine; and

a controller adapted to engage the valve actuator with the intake valve when one of the first and second temperatures is above a predetermined value, to limit an amount of fuel injected into the cylinder of the engine when the other of the first and second temperatures is below a predetermined value, and to cease limiting the amount of fuel injected into the cylinder of the engine when each of the first and second temperatures are above a predetermined value.

19. The engine system of claim 18, wherein the first sensor is adapted to sense a temperature indicative of the temperature of an engine coolant and the second sensor is adapted to sense a temperature indicative of the temperature of an intake manifold.

20. The engine system of claim 19, wherein the controller is adapted to enable the valve actuator when the engine coolant temperature is above the predetermined value and the intake manifold temperature is below the predetermined value, and adapted to disable the valve actuator when the engine coolant temperature is below the predetermined value.

21. The engine system of claim 18, further including a control valve moveable between a first position where the valve actuator is enabled and a second position where the valve actuator is disabled.

22. The engine system of claim 19, further including a detection system adapted to determine whether the valve actuator is operating properly, wherein the controller is configured to enable the valve actuator to implement a variation on a conventional engine valve actuation timing and to enable the detection system when at least the coolant temperature is above the predetermined value.

23. The engine system of claim 18, further including a cam assembly connected to the intake valve and adapted to move the intake valve between the first and second positions.

24. The engine system of claim 18, wherein the controller is adapted to limit the quantity of fuel injected into the cylinder when each of the first and second temperatures are below the predetermined value.

35. The engine system of claim 18, wherein the controller is further configured to enable a valve operation detection system to monitor the operation of the valve actuator to determine proper operation of the valve actuator, and to generate a fault condition when both the first and second temperatures are above the predetermined value and the valve operation detection system detects improper operation after having determined proper operation of the valve actuator.

36. The engine system of claim 18, wherein the controller is further configured to enable a valve operation detection system to monitor the operation of the valve actuator to determine proper operation of the valve actuator, and

to cease limiting the amount of fuel injected into the cylinder when both the first and second temperatures are above the predetermined value and the valve operation detection system determines proper operation of the valve actuator.

25. A valve actuation system for an engine having an intake valve moveable between a first position where the intake valve prevents a flow of fluid and a second position where the intake valve allows a flow of fluid, comprising:

a valve actuator adapted to selectively engage the intake valve to prevent the intake valve from returning to the first position;

a first sensor adapted to sense a first parameter indicative of a first temperature of the engine and to deliver a first signal including a representation of the first temperature;

a second sensor adapted to sense a second parameter indicative of a second temperature of the engine and to deliver a second signal including a representation of the second temperature; and

a controller adapted to receive the first and second signals and to engage the valve actuator with the intake valve when one of the first and second temperatures is above predetermined value and to limit an amount of fuel injected into a cylinder of the engine when the other of the first and second temperatures is below a predetermined value.

26. The system of claim 25, wherein the controller is adapted to cease limiting the amount of fuel injected into the cylinder of the engine when each of the first and second temperatures are above a predetermined value.

27. The system of claim 25, wherein the first sensor is adapted to sense a temperature indicative of the temperature of an engine coolant and the second sensor is adapted to sense a temperature indicative of the temperature of an intake manifold.

28. The system of claim 27, wherein the controller is adapted to enable the valve actuator when the engine coolant temperature is above the predetermined value and the intake manifold temperature is below the predetermined value, and adapted to disable the valve actuator when the engine coolant temperature is below the predetermined value.

29. The system of claim 25, further including a control valve moveable between a first position where the valve actuator is enabled and a second position where the valve actuator is disabled.

30. The system of claim 27, further including a detection system adapted to determine whether the valve actuator is operating properly, wherein the controller is configured to enable the valve actuator to implement a variation on a conventional engine valve actuation timing and to enable the detection system when at least the coolant temperature is above the predetermined value.

37. The valve actuation system of claim 25, wherein the controller is further configured to enable a valve operation detection system to monitor the operation of the valve actuator to determine proper operation of the valve actuator, and to generate a fault condition when both the first and second temperatures are above the predetermined value and the valve operation detection system detects improper operation after having determined proper operation of the valve actuator.

38. The valve actuation system of claim 25, wherein the controller is further configured to enable a valve operation detection system to monitor the operation of the valve actuator to determine proper operation of the valve actuator, and to cease limiting the amount of fuel injected into the cylinder when both the first and second temperatures are above the predetermined value and the valve operation detection system determines proper operation of the valve actuator.