Dimming mirror assembly

• US 6,164,783 A
• Filed: 02/16/1999
• Issued: 12/26/2000
• Est. Priority Date: 02/17/1998
• Status: Expired due to Fees

• Current Assignee: Magna Mirror Systems Incorporated
• Original Assignee: Magna Mirror Systems Incorporated
• Inventors: Peterson, Kenneth C.
• Primary Examiner(s): Spyrou, Cassandra
• Assistant Examiner(s): Robinson, Mark A.
• Application Number:
  US09/250,175
• Time in Patent Office: 679 Days
• Field of Search: 359/601, 359/602, 359/603, 359/608, 359/614
• US Class Current: 359/603
• CPC Class Codes: B60R 1/089 using a liquid filtering layer of variable thickness

Abstract

A dimming mirror assembly has a housing, a reflective member, a transparent member, a light reducing medium, and an actuating mechanism for introducing and evacuating the light reducing medium disposed in a gap between the transparent member and the reflective medium. The reflective member and the transparent member are carried by the housing. At least one of the transparent member and the reflective member is moveable relative to the other. The amount of light transmitted to and reflected from the reflective member is a function of the volume of light reducing medium therebetween, the volume being variable by effecting relative movement between the reflective and transparent members. The controlling mechanism may include an actuating mechanism for effecting the relative movement between the reflective and transparent members.

Claims

1. A dimming mirror assembly for a vehicle comprising:

a housing constructed and arranged to be mounted on a vehicle,

a reflective member and a cooperating transparent member together defining a mirror within said housing;

said reflective and transparent members mounted in said housing in juxtaposition with respect to one another for relative movement towards and away from one another to define a gap of variable size between said reflective and transparent members;

a light reducing medium disposed within said gap;

an actuating mechanism including a deformable member formed from an electrically deformable material adapted to deform in response to an application of voltage thereto, said deformable member having a portion thereof engaging at least one of said transparent and reflective members and another portion thereof engaging a fixed surface within said housing such that upon application of voltage to said electrically deformable material thereof said deformable member deforms to effect relative motion between said reflective and transparent members to vary the size of the gap therebetween and responsively vary an amount of light reducing medium disposed within said gap, and

a voltage regulating mechanism communicated to said actuating mechanism, said voltage regulating mechanism being adapted to regulate the voltage applied to said electrically deformable material to thereby control the size of the gap between said reflective and transparent members and the amount of light reducing medium disposed within said gap.

2. The dimming mirror assembly of claim 1, wherein said transparent member is constructed and arranged to cooperate with said housing to define a sealed enclosure for containing a fluid which comprises said light reducing medium.

3. The dimming mirror assembly of claim 1, wherein said reflective member comprises mirror glass having a reflective coating.

4. The dimming mirror assembly of claim 1, wherein said light reducing medium comprises a fluid including at least one alcohol or polyol selected from the group consisting of polyethyleneglycol, polypropyleneglycol, and butanal.

5. The dimming mirror assembly of claim 4, wherein said fluid of said light reducing medium further includes indigo dye which acts as a filter that transmits only blue wavelength light therethrough.

6. The dimming mirror assembly of claim 1, further comprising biasing structure constructed and arranged such that the relative motion between said reflective and transparent members resulting from the application of voltage to said deformable member increasingly stresses said biasing structure so that upon a decrease or removal of the voltage applied to said deformable member said biasing structure applies a biasing force that effects an opposite relative motion between said transparent and reflective members.

7. The dimming mirror assembly of claim 6, wherein voltage regulating mechanism comprises a manually operable switch.

8. The dimming mirror assembly of claim 7, wherein said deformable member comprises a shape memory allow wire.

9. The dimming mirror assembly of claim 7, wherein said deformable member comprises a plurality of shape memory alloy wires.

10. The dimming mirror assembly of claim 7, wherein said deformable member comprises a piezoelectric actuator.

11. The dimming mirror assembly of claim 10, wherein:

said piezoelectric actuator includes a laminate disposed between a pair of piezoelectric elements;

one portion of said laminate is fixed with respect to said housing and another portion of said laminate is attached to one of said reflective and transparent member such that bending of said laminate affects said relative motion between said reflective and transparent members;

said voltage regulating mechanism applies respective opposite voltages to said piezoelectric elements to expand one of said elements and contract the other of said elements to thereby bend said laminate to affect said relative motion.

12. The dimming mirror assembly of claim 11, wherein said one portion of said laminate is one end portion of said laminate which is attached in cantilever fashion to said housing and said another portion of said laminate is an opposite end portion of said laminate which is attached to said reflective member.

13. The dimming mirror assembly of claim 11, wherein said one portion of said laminate is a middle portion of said laminate which is attached to said housing and said another portion of said laminate includes a pair of opposite end portions of said laminate each of which are attached to said reflective member.

14. The dimming mirror assembly of claim 7, wherein said mirror assembly constitutes an interior, center mounted rear-view mirror of a vehicle.

15. The dimming mirror assembly of claim 7, wherein said mirror assembly constitutes an exterior, side mounted rear-view mirror of a vehicle.

16. The dimming mirror assembly of claim 15, wherein said voltage regulator mechanism is coupled to a dimming switch of an interior mirror for responsively dimming said exterior side mounted rear-view mirror upon dimming said interior mirror.

17. The dimming mirror assembly of claim 6, wherein said deformable member and said biasing structure are positioned such that said relative motion effected by the application of voltage to said deformable member is said reflective and transparent members moving apart from one another towards a maximum gap position and said opposite relative motion effected by said biasing structure is said reflective and transparent member moving towards one another towards a minimum gap position.

18. The dimming mirror assembly of claim 6, wherein said biasing structure engages said reflective member and is constructed and arranged to apply said biasing force to said reflective member to move said reflective member relative to said transparent member to affect said opposite relative motion.

19. The dimming mirror assembly of claim 18, wherein said biasing structure engages said reflective member and is constructed and arranged to apply said biasing force to said reflective member to move said reflective member relative to said transparent member to affect said opposite relative motion.

20. The dimming mirror assembly of claim 6, wherein said biasing structure includes a leaf spring.

21. The dimming mirror assembly of claim 6, wherein said biasing structure includes an air-filled O-ring.

22. The dimming mirror assembly of claim 6, wherein said biasing structure includes an O-ring of resilient material.

23. The dimming mirror assembly of claim 22, wherein said resilient material is closed cell foam.

24. The dimming mirror assembly of claim 1, wherein said housing has a surface contoured for mounting said housing on a mirror glass.

25. The dimming mirror assembly of claim 1, wherein said transparent member is fixed with respect to said housing and said reflective member is permitted to be movable relative to said transparent member.

26. The dimming mirror assembly of claim 1, wherein said deformable member comprises one or more shape memory alloy wires.

27. The dimming mirror assembly of claim 26, wherein said shape memory alloy wire is a formed from a nickel/titanium alloy.

28. The dimming mirror assembly according to claim 26, wherein said housing includes a housing reinforcement member (43) and said one or more shape memory alloy wires are fixed to said reinforcement member.

29. The dimming mirror assembly of claim 1, wherein said another portion of said deformable member is fixedly attached to said surface within said housing.

30. The dimming mirror assembly of claim 1, wherein said one portion of said deformable member is fixedly attached to said reflective member.

31. A dimming mirror assembly according to claim 1, further comprising a backing attached to said mirror, wherein said portion of said deformable member engaging at least one of said transparent and reflective members engages said reflective member through said backing.

32. A dimming mirror assembly according to claim 1, wherein said another portion of said deformable member directly engages said fixed surface within said housing.

33. A dimming mirror assembly according to claim 1, further comprising a clip attached to said mirror, wherein said portion of said deformable member engaging at least one of said transparent and reflective members engages said reflective member through said clip.