阅读说明：本技术 形状记忆合金致动装置 (Shape memory alloy actuator ) 是由 斯蒂芬·马修·邦廷 安德鲁·本杰明·辛普森·布朗 马克-赛巴斯蒂安·肖尔茨 詹姆斯·豪沃思 于 2019-01-22 设计创作，主要内容包括：概括地说,本技术提供了SMA致动装置中的形状记忆合金(SMA)致动器丝的特定布置。在一种布置中,可以使用单个直的形状记忆合金致动器丝,该形状记忆合金致动器丝可以相对于正交于移动方向的平面以大于0度的锐角倾斜。在另一种布置中,可以使用两个直的长度段的形状记忆合金致动器丝,其中SMA丝可以相对于正交于移动方向的平面以大于0度的锐角倾斜。(In general, the present technology provides particular arrangements of Shape Memory Alloy (SMA) actuator wires in SMA actuation devices. In one arrangement, a single straight shape memory alloy actuator wire may be used that may be inclined at an acute angle greater than 0 degrees relative to a plane orthogonal to the direction of movement. In another arrangement, two straight lengths of shape memory alloy actuator wire may be used, wherein the SMA wire may be inclined at an acute angle greater than 0 degrees relative to a plane orthogonal to the direction of movement.)

1. A shape memory alloy actuation apparatus comprising:

a support structure;

a movable element supported on the support structure by a suspension system arranged to guide movement of the movable element relative to the support structure in a direction of movement;

two straight length segments of shape memory alloy actuator wire, each shape memory alloy actuator wire connected to the movable element by a crimp portion and to the support structure by a crimp portion for driving movement of the movable element relative to the support structure, the shape memory alloy actuator wires being inclined at an acute angle greater than 0 degrees relative to a plane orthogonal to the direction of movement.

2. A shape memory alloy actuation apparatus according to claim 1, wherein the two shape memory alloy actuator wires have an angle of less than 180 degrees between them when viewed along the direction of movement.

3. A shape memory alloy actuation apparatus according to claim 2, wherein the two shape memory alloy actuator wires have an angle between them in the range from 70 to 110 degrees when viewed along the direction of movement.

4. A shape memory alloy actuation apparatus according to claim 3, wherein the two shape memory alloy actuator wires have an angle of 90 degrees between them when viewed along the direction of movement.

5. A shape memory alloy actuation apparatus according to any preceding claim, wherein the shape memory alloy actuator wires are inclined at the same acute angle relative to a plane orthogonal to the direction of movement.

6. A shape memory alloy actuation apparatus according to any preceding claim, wherein the shape memory alloy actuator wires are inclined in the same direction relative to a plane orthogonal to the direction of movement.

7. A shape memory alloy actuation apparatus according to claim 1, wherein the two shape memory alloy actuator wires are inclined such that one of the two SMA actuator wires drives movement of the movable element relative to the support structure in a first direction and the other of the two SMA actuator wires drives movement of the movable element relative to the support structure in a second direction, wherein the second direction is opposite to the first direction.

8. A shape memory alloy actuation apparatus according to claim 7, wherein the two shape memory alloy actuator wires are located on opposite sides of the movable element.

9. A shape memory alloy actuation apparatus according to any preceding claim, further comprising an electrical connector provided on the movable element, the electrical connector providing an electrical connection between the two shape memory alloy actuator wires.

10. A shape memory alloy actuation apparatus according to claim 9, wherein the two straight lengths of shape memory alloy actuator wire and the electrical connector are part of a single piece of SMA actuator wire.

11. A shape memory alloy actuation apparatus according to claim 1, wherein the length of shape memory alloy actuator wire is each inclined at an angle in the range 5 to 15 degrees to a plane orthogonal to the direction of movement.

12. A shape memory alloy actuation apparatus according to claim 1, wherein the length of shape memory alloy actuator wire is each inclined at an angle in the range 8 to 12 degrees to a plane orthogonal to the direction of movement.

13. A shape memory alloy actuation apparatus comprising:

a support structure;

a movable element supported on the support structure by a suspension system arranged to guide movement of the movable element relative to the support structure in a direction of movement;

only a single straight shape memory alloy actuator wire, wherein the shape memory alloy actuator wire is connected between the movable element and the support structure for driving movement of the movable element relative to the support structure and is inclined at an acute angle of more than 0 degrees relative to a plane orthogonal to the direction of movement.

14. A shape memory alloy actuation apparatus according to claim 13, wherein the shape memory alloy actuator wire is inclined at an angle in the range 5 to 15 degrees to a plane orthogonal to the direction of movement.

15. A shape memory alloy actuation apparatus according to claim 13, wherein the shape memory alloy actuator wire is inclined at an angle in the range 8 to 12 degrees to a plane orthogonal to the direction of movement.

16. A shape memory alloy actuation apparatus according to any one of claims 1 to 15, wherein the suspension system comprises a bearing arrangement.

17. A shape memory alloy actuation apparatus according to claim 16, wherein the bearing arrangement comprises at least one bearing comprising bearing surfaces on the support structure and the movable element and at least one rolling bearing element disposed between the bearing surfaces.

18. A shape memory alloy actuation apparatus according to claim 17, wherein at least one of the bearing surfaces is made of metal.

19. A shape memory alloy actuation apparatus according to claim 18, wherein at least one of the support structure and the movable element is a moulded element and the bearing surface on the at least one of the support structure and the movable element is a surface of a metal insert provided in the moulded element.

20. A shape memory alloy actuation apparatus according to claim 16, wherein the bearing arrangement comprises at least one plain bearing.

21. A shape memory alloy actuation apparatus according to any preceding claim, wherein the movable element is a lens element comprising at least one lens.

22. A shape memory alloy actuation apparatus according to claim 21, wherein the at least one lens is made of glass.

23. A shape memory alloy actuation apparatus according to claim 21 or 22, wherein the direction of movement is along an optical axis of the lens element.

24. A shape memory alloy actuation apparatus according to any one of claims 21 to 23, wherein the support structure has an image sensor mounted thereon, the lens element being arranged to focus an image on the image sensor.

25. A shape memory alloy actuation apparatus according to any one of claims 21 to 24, wherein the at least one lens has a diameter of at most 20 mm.

26. A method of assembling a shape memory alloy actuation apparatus according to claim 13 or any claim dependent thereon, the method comprising:

providing a strut element shaped to include a sacrificial strut body and crimp tabs held apart by the sacrificial strut body;

laying a shape memory alloy actuator wire across the crimping tabs of the strut elements;

folding the crimp tabs and pressing the crimp tabs against the shape memory alloy actuator wire to form crimps that hold the shape memory alloy actuator wire therebetween;

attaching the crimps to the support structure and the movable element, respectively; and

removing the sacrificial post body leaving the crimps attached to the support structure and the movable element, respectively.

27. A method of assembling a shape memory alloy actuation apparatus according to claim 1 or any claim dependent thereon, the method comprising:

providing a strut element shaped to include a sacrificial strut body and crimp tabs held apart by the sacrificial strut body;

laying at least one length of shape memory alloy actuator wire across the crimping tabs of the strut elements;

folding the crimp tabs and crimping the crimp tabs over the length of shape memory alloy actuator wire to form a crimp holding the length of shape memory alloy actuator wire therebetween;

attaching the crimps to the support structure and the movable element, respectively; and

removing the sacrificial post body leaving the crimps attached to the support structure and the movable element, respectively.

28. The method of claim 27, wherein the at least one length of shape memory alloy actuator wire comprises two lengths of shape memory alloy actuator wire.