Electronically actuated valve system

• US 20080251746A1
• Filed: 04/13/2007
• Published: 10/16/2008
• Est. Priority Date: 04/13/2007
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Riley, William, Schrader, Michael, Zagata, Mark, McConville, Gregory, Williams, Nicole, Hall, M. Matthews
• Granted Patent: US 8,434,436 B2
• Time in Patent Office: Days
• US Class Current: 251/129.04
• CPC Class Codes: F01L 1/185 Overhead end-pivot rocking arms
• CPC Class Codes: F01L 1/46 Component parts, details, or accessories, not provided for in preceding subgroups
• 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 2301/00 Using particular materials
• CPC Class Codes: F01L 2810/01 Cooling
• CPC Class Codes: F01L 9/20 by electric means

Abstract

An electronically actuated valve assembly for an internal combustion engine is disclosed, wherein the valve assembly comprises a valve stem, and a plurality of shape memory alloy segments in operative communication with the valve stem, wherein each shape memory alloy segment is individually actuatable, and wherein actuation of different shape memory alloy segments is configured to cause different valve lifts.

Claims

1. An electronically actuated valve assembly for an internal combustion engine, the valve assembly comprising:

a valve stem; and

a plurality of shape memory alloy segments in operative communication with the valve stem, wherein each shape memory alloy segment is individually actuatable, and wherein actuation of different shape memory alloy segments is configured to cause different valve lifts.

2. The valve assembly of claim 1, further comprising an individually controllable multi-level electrical connection to each shape memory alloy segment.

3. The valve assembly of claim 2, wherein the individually controllable multi-level electrical connection comprises a controller configured to selectively apply a voltage across each shape memory alloy segment.

4. The valve assembly of claim 1, wherein each shape memory alloy segment is a different shape memory alloy wire.

5. The valve assembly of claim 4, wherein each shape memory alloy wire has a different length.

6. The valve assembly of claim 4, wherein each shape memory alloy has a similar length, and further comprising a spring biasing the valve stem in a closed direction.

7. The valve assembly of claim 4, further comprising a rocker arm to which the valve stem is coupled, and wherein each shape memory alloy segment is coupled to a different location on the rocker arm to impart a different mechanical advantage for moving the rocker arm.

8. The valve assembly of claim 1, wherein two or more shape memory alloy segments are on a single shape memory alloy wire.

9. The valve assembly of claim 8, further comprising at least one intermediate electrical connection to the single shape memory alloy wire.

10. An electronically actuated valve assembly for an internal combustion engine, the valve assembly comprising:

a valve stem;

a plurality of shape memory alloy segments in operative communication with the valve stem; and

an individually controllable multi-level electrical connection to each shape memory alloy segment.

11. The valve assembly of claim 10, wherein each shape memory alloy segment is a different shape memory alloy wire.

12. The valve assembly of claim 11, wherein each shape memory alloy wire has a different length.

13. The valve assembly of claim 11, wherein each shape memory alloy has a similar length, and further comprising a spring biasing the valve stem in a closed direction.

14. The valve assembly of claim 10, wherein two or more shape memory alloy segments are on a single shape memory alloy wire.

15. The valve assembly of claim 14, further comprising at least one intermediate electrical connection to the single shape memory alloy wire.

16. The valve assembly of claim 10, further comprising a controller configured to selectively apply a voltage across each shape memory alloy segment.

17. An apparatus, comprising:

an internal combustion engine;

a controller; and

an electronic valve actuator in electrical communication with the controller, the electronic valve actuator comprising a plurality of individually actuatable shape memory alloy segments.

18. The apparatus of claim 17, wherein the controller is configured to selectively apply a voltage across each shape memory alloy segment.

19. The apparatus of claim 17, wherein each shape memory alloy segment is a different shape memory alloy wire.

20. The valve assembly of claim 19, wherein each shape memory alloy wire has a different length.

21. The valve assembly of claim 19, wherein each shape memory alloy has a similar length, and further comprising a spring biasing the valve stem in a closed direction.

22. The valve assembly of claim 17, wherein two or more shape memory alloy segments are on a single shape memory alloy wire.

23. The valve assembly of claim 22, further comprising at least one intermediate electrical connection to the single shape memory alloy wire.