阅读说明：本技术 相机模块自动聚焦致动器 (Camera module autofocus actuator ) 是由 马库斯·克普费尔 于 2018-04-20 设计创作，主要内容包括：相机模块自动聚焦致动器包括可移动的透镜承载件、一个或更多个形状记忆合金线、第一弹性回复元件、与第一弹性回复元件大致相同并且对称的第二弹性回复元件,其中,一个或更多个形状记忆合金线的一个端部安装至第一弹性回复元件,并且一个或更多个形状记忆合金线的另一个端部安装至另一个弹性回复元件。(The camera module autofocus actuator includes a movable lens carrier, one or more shape memory alloy wires, a first elastic restoring element, a second elastic restoring element substantially identical and symmetrical to the first elastic restoring element, wherein one end of the one or more shape memory alloy wires is mounted to the first elastic restoring element and another end of the one or more shape memory alloy wires is mounted to the other elastic restoring element.)

1. A camera module autofocus actuator, comprising:

-a fixed support member (1; 1'),

-a movable lens carrier (2; 2 '), the lens carrier (2; 2') being slidingly received on the fixed support member (1; 1 ') such that the lens carrier (2; 2') moves along an optical axis (A),

-one or more shape memory alloy wires (4; 7), the one or more shape memory alloy wires (4; 7) being arranged to be activated to cause the movable lens carrier (2; 2') to move in a first direction along the optical axis (A),

-a first elastic restoring element (3; 5; 6; 8), the first elastic restoring element (3; 5; 6; 8) being mounted between the support member (1; 1 ') and the lens carrier (2; 2') such that the first elastic restoring element (3; 5; 6; 8) generates only a restoring force parallel to the optical axis (A) in a second direction opposite to the first direction, wherein the first direction is determined by activation of the shape memory alloy wire (4; 7),

-at least a second elastic restoring element (3; 5; 6; 8), said at least second elastic restoring element (3; 5; 6; 8) being substantially identical to said first elastic restoring element (3; 5; 6; 8) and being mounted in the same way as said first elastic restoring element (3; 5; 6; 8), said elastic restoring elements (3; 5; 6; 8) being arranged at symmetrically opposite positions with respect to said optical axis (A),

the actuator is characterized in that it is provided with,

-each of said one or more shape memory alloy wires (4; 7) is mounted so that a first end is directly fixed to one of said elastic restoring elements (3; 5; 6; 8) and a second end is directly fixed to the same elastic restoring element (3; 5; 6; 8) as the one to which it is fixed, or to any of the other elastic restoring elements (3; 5; 6; 8) or to the support member (1; 1'),

such that the movement of the lens carrier (2; 2') is caused by the elastic restoring element (3; 5; 6; 8).

2. Camera module autofocus actuator according to claim 1, characterized in that the fixed support member (1; 1 ') and the movable lens carrier (2; 2') have a substantially square or rectangular shape in a plane orthogonal to the optical axis (A), and the fixed support member (1; 1 ') and the movable lens carrier (2; 2') are coupled in a sliding manner by at least four guide posts (1 a; 1a ') extending parallel to the optical axis (A), the at least four guide posts (1 a; 1 a') preferably being formed at corners on the support member (1; 1 ') in engagement with matching grooves (2 a; 2 a') preferably being formed on the lens carrier (2; 2 '), wherein dimensional tolerances ensure a maximum inclination of 0.08 degrees and at the support member (1; 1') with the lens carrier (2; 2) ') no rolling elements are arranged between them.

3. Camera module autofocus actuator according to claim 2, characterized in that the support member (1; 1 ') is made of polybutylene terephthalate and the lens carrier (2; 2 ') is made of copolymer polyoxymethylene, wherein the guide posts (1 a; 1a ') may be made of metal.

4. Camera module autofocus actuator according to any of the preceding claims, characterized in that it comprises four identical elastic return elements (3; 5) and two straight shape memory alloy wires (4), wherein the four identical elastic return elements (3; 5) are arranged in two pairs, the two elements (3; 5) of each pair comprising mounting arrangements in a common plane parallel to the optical axis (A) with symmetrically opposite symmetry with respect to the optical axis (A), each of the two straight shape memory alloy wires (4) being preferably mounted in a horizontal manner between two elements (3; 5) of the same pair.

5. Camera module autofocus actuator according to claim 4, characterized in that each elastic return element (3) comprises a flexible strip, preferably made of metal, mounted such that the first end (3a) is fixed to the support member (1; 1 ') at a lower outermost position and such that the second end (3b) is fixed to the lens carrier (2; 2') at an upper innermost position.

6. Camera module autofocus actuator according to claim 5, characterized in that each elastic return element (3) further comprises an upright (3c), said upright (3c) extending substantially vertically upwards from the mounting position of the first end (3a) of the strap to at least the following height: the height being the height at which the mounting position of the second end (3b) of the strap is located when the shape memory alloy wire (4) is not activated, wherein the shape memory alloy wire (4) is mounted between the uprights (3c) substantially at said height.

7. Camera module autofocus actuator according to claim 4, characterized in that each elastic restoring element comprises a horizontal V-shaped flexible connector (5), the horizontal V-shaped flexible connector (5) being mounted such that the vertex (5a) of the horizontal V-shaped flexible connector (5) is outermost with respect to the end (5b) of the horizontal V-shaped flexible connector (5).

8. Camera module autofocus actuator according to claim 7, characterized in that the ends (5b) of each horizontal V-shaped flexible connector (5) are connected to the support member (1; 1 ') and the lens carrier (2; 2'), respectively, at vertically aligned positions, and wherein each shape memory alloy wire (4) is mounted between the vertices (5a) of two horizontal V-shaped flexible connectors (5) of each pair of horizontal V-shaped flexible connectors (5).

9. The camera module autofocus actuator of any of claims 1 to 3, characterized in that the camera module autofocus actuator comprises two identical diamond-shaped elastic return elements (6) and two straight shape memory alloy wires (4), the diamond-shaped elastic return element (6) being mounted so that a bottom vertex (6a) is fixed to the support member (1; 1 ') and is vertically aligned with a top vertex (6b) fixed to the lens carrier (2; 2'), each of said two straight shape memory alloy wires (4) is mounted within one of said diamond-shaped elastic restoring elements (6), preferably between two horizontally aligned intermediate vertices (6c) of said diamond-shaped elastic restoring element (6).

10. The camera module autofocus actuator of any one of claims 1 to 3, characterized in that it comprises four identical elastic restoring elements comprising a horizontal V-shaped flexible connector (5) mounted such that the vertex (5a) of the horizontal V-shaped flexible connector (5) is at an outermost position with respect to the end (5b) of the horizontal V-shaped flexible connector (5), and a single shape memory alloy wire (7), the four identical elastic restoring elements being arranged in two pairs, wherein two elements of each pair of elastic restoring elements are comprised in a common plane containing the optical axis (A) with symmetrically opposite mounting arrangements with respect to the optical axis (A), the single shape memory alloy wire (7) is mounted in a horizontal manner to connect all four identical elastic return elements continuously along the outer circumference of the actuator.

11. Camera module autofocus actuator according to claim 10, characterized in that the end (5b) of each horizontal V-shaped flexible connector (5) is connected to the support member (1; 1 ') and the lens carrier (2; 2'), respectively, at a vertically aligned position, and wherein the shape memory alloy wire (7) is mounted between the vertices (5a) of the four horizontal V-shaped flexible connectors (5).

12. The camera module autofocus actuator according to any of claims 1 to 3, characterized in that it comprises two identical rod-and-link elastic restoring elements (8) and a shape memory alloy wire (4), each of the two identical rod-and-link elastic restoring elements (8) comprising a rod (8a), the rod (8a) pivoting (9a) above the support member (1; 1 ') and carrying a link (8b), the link (8b) pivoting (9b, 9c) between the rod (8a) and the lens carrier (2; 2') in a horizontal central position of the lens carrier (2; 2 '), the shape memory alloy wire (4) being fixed between the support member (1; 1') and the rod (8a), the pivot connections (9a, 9b, 9c) between the elements (1, 2, 8a, 8b) are realized by sheet-like hinges made of plastic, so that at least one of the pivot connections (9a, 9b, 9c) also acts as a torsion spring.

13. Camera module autofocus actuator according to claim 12, characterized in that the lever (8a) is pivoted in a substantially horizontal direction over the support member (1; 1 ') by a pivot (9a) when the actuator is in a rest position, the pivot (9a) being located at the top of an upright (1b), the upright (1b) extending from the base of the support member (1; 1') up to the top edge of the lens carrier (2; 2 ') on a first side relative to a central part of the actuator, while the link (8b) is pivoted almost vertically between a horizontal central part of the lens carrier (2; 2') and an end of the lever (8a) located on a second side opposite the first side relative to the pivot (9a), and the SMA wire (4) is fixed between a corner of the support member (1; 1') on the second side and an end of the lever (8a) on the first side with respect to the pivot (9a), the SMA wire (4) passing under the pivot (9 a).

14. Camera module autofocus actuator according to any of the preceding claims, characterized in that each shape memory alloy wire (4; 7) preferably comprises at one of its ends a spring with a stiffness which in normal actuator operation acts as a rigid connecting member, whereas the spring acts as a fail-safe member providing an elongation sufficient to absorb the contraction of the shape memory alloy wire (4; 7) in case the shape memory alloy wire (4; 7) is forced to operate on an immovable jammed lens carrier (2; 2').

15. Camera module autofocus actuator according to any of the preceding claims, characterized in that the elastic restoring element (3; 5; 6; 8) is made of glass fiber reinforced plastic, preferably with a Young's modulus comprised between 14 and 15 GPa.