Engine shut-down for engine having adjustable valve timing

• US 7,549,406 B2
• Filed: 01/02/2008
• Issued: 06/23/2009
• Est. Priority Date: 03/19/2004
• Status: Expired due to Fees

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Lewis, Donald J.
• Primary Examiner(s): Huynh; Hai H
• Application Number:
  US11/968,313
• Publication Number:
  US 20080098980A1
• Time in Patent Office: 538 Days
• Field of Search: 123/322, 123/347, 123/90.11, 123/198.D, 123/198.F, 701/112
• US Class Current: 123/198.00F
• CPC Class Codes: F01L 1/14 Tappets hydraulic tappets for automatically adjusting or compensating clearance F01L1/24; Push rods
• CPC Class Codes: F01L 1/146 Push-rods
• CPC Class Codes: F01L 13/0005 Deactivating valves
• CPC Class Codes: F01L 2009/2136 Two opposed springs for intermediate resting position of the armature
• CPC Class Codes: F01L 2800/03 Stopping; Stalling
• CPC Class Codes: F02D 13/0215 changing the valve timing only
• CPC Class Codes: F02D 13/0234 changing the valve timing only
• CPC Class Codes: F02D 13/0253 Fully variable control of valve lift and timing using camless actuation systems such as hydraulic, pneumatic or electromagnetic actuators, e.g. solenoid valves
• CPC Class Codes: F02D 13/0257 Independent control of two or more intake or exhaust valves respectively, i.e. one of two intake valves remains closed or is opened partially while the other is fully opened
• CPC Class Codes: F02D 13/06 Cutting-out cylinders
• CPC Class Codes: F02D 17/02 Cutting-out cutting-out engines in multiple engine arrangements F02D25/04
• CPC Class Codes: F02D 2041/001 for engines with variable valve actuation
• CPC Class Codes: F02D 2041/0095 Synchronisation of the cylinders during engine shutdown
• CPC Class Codes: F02D 35/0023 Controlling air supply
• CPC Class Codes: F02D 37/02 one of the functions being ignition
• CPC Class Codes: F02D 41/0002 Controlling intake air
• CPC Class Codes: F02D 41/042 for stopping the engine
• CPC Class Codes: F02D 41/047 Taking into account fuel evaporation or wall wetting; special correction after fuel cut-off F02D41/126
• CPC Class Codes: F02D 41/1484 Output circuit
• CPC Class Codes: F02N 99/004 Generation of the ignition spark
• CPC Class Codes: F02N 99/006 : Providing a combustible mixture inside the cylinder
• CPC Class Codes: Y02T 10/40 : Engine management systems

Abstract

A method for discontinuing combustion in a cylinder of an internal combustion engine having an intake manifold and an emission control device coupled downstream of thereof, where the cylinder has at least one valve, the method comprising during a shut-down and after a final combustion event in the cylinder, adjusting valve timing of the valve to reduce a flow of gasses from the engine to the emission control device.

Claims

1. A method for discontinuing combustion in a cylinder of an internal combustion engine having an intake manifold and an emission control device coupled downstream of thereof, where the cylinder has at least one valve, the method comprising:

during a shut-down and after a final combustion event in the cylinder, adjusting valve timing of the valve to reduce a flow of gasses from the engine to the emission control device.

2. The method of claim 1 further comprising maintaining another valve in a closed position during said shut-down and after the final combustion event.

3. The method of claim 2 further comprising during conditions where the another valve is in said closed position, operating with the valve open, then closing the valve, and then opening the valve to generate braking torque to slow the engine.

4. The method of claim 1 where said valve is an intake valve.

5. The method of claim 1 where said valve is an exhaust valve.

6. The method of claim 5 further comprising opening the exhaust valve to expel combustion gasses of the final combustion event, and then holding the exhaust valve closed until engine speed is at least less than 100 rpm, and then releasing the exhaust valve to a neutral position.

7. The method of claim 6 where an intake valve is held closed after the final combustion event.

8. The method of claim 5 where the intake valve timing is adjusted to extend an intake valve opening duration.

9. The method of claim 5 where the intake valve timing is adjusted to retard an intake valve closing timing.

10. The method of claim 5 where the intake valve timing is adjusted, where the intake valve opens after an exhaust valve of the cylinder closes.

11. The method of claim 5 where the intake valve timing is adjusted so the intake valve opens between −

30 to +30 degrees after TDC exhaust stroke and closes between −

30 to +30 degrees after TDC compression stroke.

12. The method of claim 1 further comprising, after the final combustion event, holding one of an intake and exhaust valve open while holding the other of the intake and exhaust valve closed during a plurality of piston cycles of the cylinder, until the engine speed falls below a threshold and both the intake and exhaust valve are released to a neutral position.

13. A method for discontinuing combustion in a cylinder of an internal combustion engine having an intake manifold and an emission control device coupled downstream of thereof, where the cylinder has at least one electrically actuated intake valve, the method comprising:

during a shut-down and after a final combustion event in the cylinder, adjusting valve timing of the intake valve to reduce a flow of gasses from the engine to the emission control device, where the intake valve opening duration is increased.

14. The method of claim 13 further comprising releasing the intake valve to a neutral position at least after engine speed falls below 100 RPM.

15. The method of claim 13 where the intake valve timing is adjusted so that intake valve opens after an exhaust valve of the cylinder closes from exhausting gasses from the final combustion event.

16. The method of claim 13 where the intake valve timing is adjusted so the intake valve opens between −

30 to +30 degrees after TDC exhaust stroke and closes between −

30 to +30 degrees after TDC compression stroke.