CN216959998U - SMA actuating mechanism and camera module - Google Patents

Abstract

The application discloses SMA actuating mechanism and camera module belongs to electron technical field. The SMA actuation mechanism of the present application comprises: a support structure having a height direction that is a first direction; a moving element having a gap with the support structure, the moving element being movable relative to the support structure; the SMA structure comprises a first SMA wire group and a second SMA wire group which are arranged in a first direction; each SMA wire group comprises at least one pair of SMA wires arranged at an included angle; in the SMA structure, each SMA wire is fixedly connected with one side of the moving element and the supporting structure; the SMA structure is adapted to drive the moving element relative to the support structure in at least a first direction and an opposite direction. The SMA actuating mechanism has the advantages that the occupied space is small, the driving force is large, the moving element can move along at least two opposite directions relative to the supporting structure, and meanwhile, the length of the SMA wire is convenient to adjust, so that the maximum driving stroke can be conveniently obtained, and the SMA actuating mechanism is easy to process and assemble.

Description

SMA actuating mechanism and camera module

Technical Field

The application relates to the technical field of electronics, in particular to an SMA actuating mechanism and a camera module.

Background

SMA is a shape memory alloy (shape memory alloy) which is a material composed of two or more metal elements having a shape memory effect by thermo-elastic and martensitic transformation and inversion thereof. The SMA wire is kept in a relaxed state at a lower temperature, and after the SMA wire is heated by supplying current, the SMA wire is deformed and contracted, so that the SMA wire has different contraction quantities at different temperatures, and therefore, the SMA wire can generate certain tension when being contracted; however, when the current of the SMA wire is interrupted, the SMA wire is naturally cooled and gradually relaxes, and in the process, the tensile force of the SMA wire gradually disappears. Therefore, the SMA wire is connected with the movable piece and the static piece, and the current flowing on the SMA wire is controlled, so that the moving distance of the movable piece relative to the static piece in one direction can be controlled, and the electrically controlled contraction is realized.

In the field of electronic related to camera shooting, particularly focusing or anti-shaking, a lens is arranged on a moving part, a photosensitive element is arranged on a static part, and an SMA wire actuating structure is connected with the static part and the moving part.

Based on the above characteristics of the SMA wire, in order to reset the lens after focusing or anti-shake operation, a plurality of SMA wire actuation structures are often provided, and are respectively connected to different sides of the moving member and the stationary member, two SMA actuation structures located on opposite sides of the moving member are responsible for movement of the moving member in one direction, and two SMA actuation structures located on adjacent sides of the moving member are responsible for movement of the moving member in two opposite directions.

For example, as in the technical solution shown in chinese patent No. CN102770804B, although the SMA actuation structure has a large driving force and can realize movement of the lens in multiple directions, the SMA actuation structure has a complex structure, which results in a large assembly difficulty, an assembly error being difficult to control, and difficulty in mass production. Or, there is also a SMA actuating structure only disposed on one side of the moving part, for example, chinese patent No. CN214540194U, in this type of technical solution, the SMA actuating structure includes two SMA wires bent in a V shape and having opposite bending directions and a driven part disposed on the moving part, and a vertex of the V-bend of the two SMA wires is hooked on the driven part, so as to implement the lens moving in two opposite directions, this solution can reduce the number of SMA actuating structures and reduce the height of the SMA actuating structure, but because the SMA wires are hooked on the driven part, during the lens moving process, the vertex of the V-bend on the SMA wires changes, and the position of the driven part relative to the SMA wires changes, so that when large shake occurs, the driven part is easily disconnected from the SMA wires, so that the lens cannot be focused or anti-shake; and, limited by the assembly structure, the length of the SMA wire is difficult to adjust, resulting in a smaller adjustment range of the driving stroke; in addition, because the driven part is not fixedly connected with the SMA wire, the SMA wire is easy to separate from the driven part in the assembling process, and the assembling difficulty is high.

SUMMERY OF THE UTILITY MODEL

The present application is directed to solving one of the technical problems in the prior art. Therefore, the SMA actuating mechanism occupies a small space and has a large driving force, the moving element can move along at least two opposite directions relative to the supporting structure, and meanwhile, the length of the SMA wire is convenient to adjust, so that the maximum driving stroke is convenient to obtain, and the SMA actuating mechanism is easy to machine and assemble. The application also provides a camera module.

An SMA actuation mechanism according to a first aspect of the application comprises:

a support structure having a height direction that is a first direction;

a moving element formed with a gap from the support structure, the moving element being movable relative to the support structure;

the SMA structure comprises a first SMA wire group and a second SMA wire group which are arranged in a first direction; each SMA wire group comprises at least one pair of SMA wires arranged at an included angle with each other; each SMA wire in the SMA structure is fixedly connected with one side of the moving element and the support structure; the SMA structure is used for driving the moving element to move relative to the supporting structure at least along a first direction and a reverse direction.

The SMA actuating mechanism according to the embodiment of the application has at least the following beneficial effects:

each SMA wire group is provided with at least one pair of SMA wires which form an included angle with each other, the arrangement is such that when one group of SMA wire groups is electrified, two SMA wires in the same pair of SMA wires on the group of SMA wire groups shrink, the included angle between the two SMA wires becomes smaller, and the driving force generated by the two SMA wires for the moving element is similar to the arrangement mode that the SMA wires are arranged in a V shape in related design, so that the moving element is pulled to move relative to the supporting structure; and the stroke amount of the moving element moving relative to the support structure is far larger than the contraction amount of the SMA wire, so that the stroke amplification effect is realized.

Meanwhile, two groups of SMA wire groups are arranged in the same SMA structure in the first direction and are respectively used for driving the moving element to move in the first direction and the opposite direction of the moving element relative to the supporting structure, so that the moving element can move stably and without friction relative to the supporting structure only by arranging one SMA structure, the number of the SMA structures is reduced, the assembly difficulty can be greatly reduced, and the mass production difficulty can be reduced.

Moreover, each SMA wire group is at least provided with two SMA wires, and the SMA actuating mechanism can have a larger driving stroke in a limited assembly space by adjusting the length of each SMA wire in the same SMA wire group, so that the driving stroke requirement is met.

According to some embodiments of the present application, in each SMA wire group, two SMA wires arranged at an included angle to each other are symmetrically arranged.

According to some embodiments of the present application, the first set of SMA wires and the second set of SMA wires are arranged asymmetrically.

According to some embodiments of the present application, the two sets of SMA wire sets are symmetrically arranged in the first direction.

According to some embodiments of the present application, in each SMA wire group, two SMA wires arranged at an angle to each other in the same pair have different lengths.

According to some embodiments of the present application, in each SMA wire group, two SMA wires arranged at an included angle to each other are arranged in a crossing manner.

According to some embodiments of the present application, at least two pairs of the SMA wires are provided in the same SMA wire group.

According to some embodiments of the application, a plurality of connecting pieces for electrically connecting with a controller are arranged on the supporting structure and the moving element, and two ends of each SMA wire are connected to the connecting pieces.

According to some embodiments of the application, each connecting piece is correspondingly connected with one end of each SMA wire.

According to some embodiments of the application, the SMA wires of a pair are connected to the same connecting piece on the support structure or on the moving element.

According to some embodiments of the present application, one end of one of the SMA wires on the first SMA wire group is connected to the same connecting piece as one end of one of the SMA wires on the second SMA wire group.

According to some embodiments of the application, a spring is arranged between the moving element and the support structure, the spring being configured to support the moving element.

According to some embodiments of the application, the spring connects the support structure top surface and the moving element top surface, and/or the spring connects the support structure bottom surface and the moving element bottom surface.

The camera module according to the second aspect of the present application includes a lens, a photosensitive element and the SMA actuation mechanism.

According to some embodiments of the present application, the lens is disposed on the moving element, the photosensitive element is disposed on the supporting structure, and the SMA actuating mechanism is configured to drive the moving element to drive the lens to move relative to the photosensitive element, so as to implement focusing or anti-shake operations.

According to some embodiments of the present application, the lens is disposed on the supporting structure, the photosensitive element is disposed on the moving element, and the SMA actuating mechanism is configured to drive the moving element to drive the photosensitive element to move relative to the lens, so as to implement focusing or anti-shake operations.

Additional aspects and advantages of the present application will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the present application.

Drawings

The above and/or additional aspects and advantages of the present application will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a schematic diagram of an SMA structure in a first embodiment of the present application.

Fig. 2 is a schematic view of an SMA structure according to a second embodiment of the present application.

Fig. 3 is a schematic diagram of an SMA structure in a third embodiment of the application.

Fig. 4 is a schematic representation of an SMA structure according to a fourth embodiment of the present application.

Fig. 5 is a schematic view of an SMA structure in a fifth embodiment of the present application.

Fig. 6 is a schematic view of an SMA structure according to a sixth embodiment of the present application.

Fig. 7 is a schematic view of an SMA structure according to a seventh embodiment of the present application.

Fig. 8 is a schematic view of an SMA structure in an eighth embodiment of the application.

Fig. 9 is a schematic view of an SMA structure in a ninth embodiment of the application.

Fig. 10 is a schematic view of an SMA structure in a tenth embodiment of the application.

Fig. 11 is a schematic representation of an SMA structure according to an eleventh embodiment of the application.

Fig. 12 is a schematic representation of an SMA structure according to a twelfth embodiment of the application.

Fig. 13 is a schematic representation of an SMA structure according to a thirteenth embodiment of the application.

Fig. 14 is a schematic view of an SMA structure in a fourteenth embodiment of the application.

Fig. 15 is a schematic view of an SMA structure in a fifteenth embodiment of the present application.

Fig. 16 is a schematic view of an SMA structure in a sixteenth embodiment of the application.

Fig. 17 is a schematic diagram showing an SMA wire according to the present application.

FIG. 18 is a schematic view of an SMA actuation mechanism in one implementation of the present application.

Fig. 19 is a schematic diagram of an SMA actuation mechanism in another implementation of the present application.

Fig. 20 is a schematic view of a camera module according to the second aspect of the present application.

Detailed Description

Reference will now be made in detail to the embodiments of the present application, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary only for the purpose of explaining the present application and are not to be construed as limiting the present application.

In the description of the present application, it is to be understood that the positional descriptions, such as the directions of up, down, left, right, front, rear, and the like, referred to as positional or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present application.

In the description of the present application, unless otherwise expressly limited, terms such as set, mounted, connected and the like should be construed broadly, and those skilled in the art can reasonably determine the specific meaning of the terms in the present application by combining the detailed contents of the technical solutions.

An SMA actuation mechanism according to the first aspect of the present application is described below with reference to fig. 1 to 19.

Referring to fig. 1-18, the SMA actuation mechanism of the present application comprises:

a support structure 100 having a height direction as a first direction;

a mobile element 200, able to move with respect to the support structure 100;

an SMA structure 300 comprising a first SMA wire set 310 and a second SMA wire set 320 arranged in a first direction; each SMA wire group comprises at least one pair of SMA wires arranged at an included angle with each other, and each SMA wire in the SMA structure 300 is fixedly connected to one side of the moving element 200 and the support structure 100; the two sets of SMA wire sets are used to drive the moving element 200 to move relative to the support structure 100 in at least a first direction and an opposite direction.

It is to be understood that, in some embodiments below, a pair of SMA wires is disposed in the first SMA wire group 310 as an example. Specifically, a first SMA wire 311 and a second SMA wire 312 which form an included angle with each other are provided; and, taking a pair of SMA wires disposed in the second SMA wire group 320 as an example, a third SMA wire 321 and a fourth SMA wire 322 are disposed at an included angle.

It will be appreciated that in the series of illustrations that follow, the first direction is parallel to the height direction of the support structure 100; the second direction is perpendicular to the first direction, i.e., parallel to the width direction of the support structure 100; the third direction is perpendicular to both the first direction and the second direction. Further, in the SMA actuation mechanism, a virtual main axis a is provided, which is understood to be parallel to the first direction.

When the SMA actuation mechanism is used in different fields, the moving element 200 may be of any shape. Taking the related field of image pickup as an example: the main shaft a is an optical axis; the moving element 200 may be cylindrical or rectangular; meanwhile, the support structure 100 may be provided to be located at the side of the moving element 200 for enabling the SMA structure 300 to connect the side of the moving element 200 and the support structure 100; the support structure 100 may also be provided as a structure with a receiving cavity in which the moving element 200 is movable, in which case only one SMA structure 300 may be provided for connecting one side of the moving element 200 to the support structure 100, or a plurality of SMA structures 300 may be provided, each SMA structure 300 being provided for connecting a different side of the moving element 200 to a different side of the support structure 100.

It is understood that in the same SMA structure 300, two sets of SMA wire sets, namely the first SMA wire set 310 and the second SMA wire set 320, are provided, and the two sets of SMA wire sets are oppositely arranged in the first direction. Furthermore, each set of SMA wires comprises at least one pair of SMA wires, each pair of SMA wires comprising two SMA wires arranged at an angle to each other, wherein both ends of each SMA wire are connected to the moving element 200 and the support structure 100. In general, in the same pair of SMA wires, the ends of the two SMA wires close to each other are connected to the moving element 200, the ends of the two SMA wires far from each other are connected to the support structure 100, or vice versa.

Each SMA wire group is provided with at least one pair of SMA wires which form an included angle with each other, so that when one group of SMA wire groups is electrified, two SMA wires in the same pair of SMA wires on the group of SMA wire groups shrink, the included angle between the two SMA wires becomes smaller, the driving force generated by the two SMA wires for the moving element 200 is similar to the arrangement mode that the SMA wires are arranged in a V shape in related design, so that the moving element 200 is pulled to move relative to the support structure 100, and the stroke amount of the moving element 200 relative to the support structure 100 is far greater than the shrinkage amount of the SMA wires, so that the stroke amplification effect is achieved.

Meanwhile, in the same SMA structure 300, two sets of SMA wire groups are oppositely arranged in the first direction, and the two sets of SMA wire groups are respectively used for driving the moving element 200 to move in two opposite directions relative to the supporting structure 100, so that the moving element can be stably supported and move without friction only by arranging one SMA structure 300, the number of the SMA structures 300 is saved, the assembly difficulty can be greatly reduced, and the mass production difficulty is reduced.

Referring to fig. 17, the end of the SMA wire to which the support structure 100 is attached is referred to as a head end 300a, while the end to which the moving element 200 is attached is referred to as an end 300 b.

The SMA actuating mechanism is arranged in such a way that each SMA wire can be adjusted according to the actual assembly space so as to enable the SMA actuating mechanism to have the maximum driving stroke. Specifically, in the first broad case of fig. 1-7, the distance between the ends 300b of the two SMA wires in the same pair is small, and in the second broad case of fig. 8-11, the distance between the ends 300b of the two SMA wires in the same pair is large, and the drive stroke of the SMA actuation mechanism in the second broad case is much greater than that in the first broad case. Therefore, the lengths of the SMA wires are changed according to actual conditions, so that the driving stroke of the SMA actuating structure can be improved as much as possible in a limited assembly space.

Referring to fig. 1 to 12, in the first embodiment, in each SMA wire group, two SMA wires arranged at an angle to each other are symmetrically arranged.

That is, the first SMA wire 311 and the second SMA wire 312 are equal in length, and the first SMA wire 311 and the second SMA wire 312 are symmetrically disposed about the principal axis a in a front view. In this case, the first SMA wire 311 and the second SMA wire 312 are applied with equal currents, so that the first SMA wire 311 and the second SMA wire 312 contract by the same amount. Specifically, the component force of the pulling force on the moving element 200 generated by the contraction of the first SMA wire 311 is a first vertical component force parallel to the main axis a and a first transverse component force and a resultant force perpendicular to the main axis a, and the resultant force is along the length direction of the first SMA wire 311; similarly, the second SMA wire 312 has a component force of a pulling force on the moving element 200 that is a second vertical component force parallel to the main axis a, a second lateral component force perpendicular to the main axis a, and a resultant force along the length direction of the second SMA wire 312, wherein the first vertical component force and the second vertical component force have the same magnitude and direction, and the first lateral component force and the second lateral component force have the same magnitude and opposite directions, so that the moving element 200 can move stably along the main axis a.

In this arrangement, the SMA wires in the second SMA wire group 320 are arranged in the same manner as the first SMA wire group 310. After the first SMA wire group 310 drives the moving element 200 to a certain position and when the moving element 200 needs to be pulled back to reset, the current flowing through each SMA wire in the first SMA wire group 310 is reduced, and the current flowing through each SMA wire in the second SMA wire group 320 is increased at the same time, so that each SMA wire in the first SMA wire group 310 can still keep the pulling force on the moving element 200 in the process of pulling the moving element 200 to reset by the second SMA wire group 320; it should be noted that the pulling force of the second SMA wire set 320 on the moving element 200 is greater than that of the first SMA wire set 310, so that the moving element 200 does not deflect during the resetting process.

Referring to fig. 12, in a second embodiment, the first SMA wire set 310 and the second SMA wire set 320 are arranged asymmetrically. For example, the SMA wires in the first SMA wire group 310 are symmetrically arranged, and the SMA wires in the second SMA wire group 320 are also symmetrically arranged, but it should be noted that the lengths of the SMA wires in the first SMA wire group 310 are not the same as the lengths of the SMA wires in the second SMA wire group 320. That is, the first SMA wire 311 and the third SMA wire 321 are not of the same length, and the second SMA wire 312 and the fourth SMA wire 322 are not of the same length. So configured, when the SMA wires in the first SMA wire set 310 and the second SMA wire set 320 are applied with the same magnitude of current, the total contraction amount of the SMA wires in the first SMA wire set 310 is smaller than that of the SMA wires in the second SMA wire set 320, and therefore, the driving strokes of the moving element 200 in the first SMA wire set 310 and the second SMA wire set 320 in the unit time are not the same, and it can also be understood that the moving speeds of the moving element 200 in the opposite two directions are not the same. Therefore, the design can be used in some occasions, such as the situation that when focusing is carried out on a lens in an image pickup system, quick and accurate focusing is needed, and when resetting is needed, slow resetting is needed.

Referring to fig. 1-11, in a third embodiment, the first SMA wire set 310 and the second SMA wire set 320 are symmetrically arranged. It is to be understood that the angle between the first and second SMA wires 311, 312 is equal to the angle between the third and fourth SMA wires 321, 322, and that the first, second, third and fourth SMA wires 311, 312, 321, 322 are equal in length. So configured, the driving strokes of the first SMA wire set 310 and the second SMA wire set 320 to the moving element 200 in the unit time are the same, that is, the moving speeds of the moving element 200 in the opposite two directions are the same.

Referring to fig. 13 and 14, in a fourth embodiment, the first and second SMA wires 311, 312 are not equal in length. Take the example that the length of the first SMA wire 311 is greater than the length of the second SMA wire 312. The first SMA wire 311 and the second SMA wire 312 are not symmetrically disposed about the principal axis a in a front view. In this case, when the first SMA wire 311 and the second SMA wire 312 are applied with the same magnitude of current, the amounts of contraction of the first SMA wire 311 and the second SMA wire 312 are different, and the respective pulling forces on the moving element 200 are also different. Specifically, the first SMA wire 311 has the same direction and different magnitude of the first vertical component and the second vertical component of the force applied to the moving element 200 by the first SMA wire 311, and has the opposite direction and different magnitude of the first lateral component and the second lateral component of the force, and therefore, the moving element 200 is deflected along the principal axis a with respect to the support structure 100 in a front view, and the deflection direction is directed toward the first SMA wire 311 side.

Similarly, for the second SMA wire group 320, the arrangement manner may be the same as that of the first SMA wire group 310, that is, as shown in fig. 13, the first SMA wire group 310 and the second SMA wire group 320 are symmetrically arranged in the first direction; alternatively, as shown in fig. 14, the first SMA wire set 310 and the second SMA wire set 320 are arranged centrosymmetrically from the front view, and are arranged such that the moving element 200 can move reversely along the moving track thereof and reset under the same current intensity.

Referring to fig. 2 to 12 and fig. 16, in a fifth embodiment, in each SMA wire group, two SMA wires arranged at an angle to each other in the same pair are arranged crosswise. The cross arrangement can increase the length of the SMA wires on the premise of not increasing the occupied volume of the SMA actuating mechanism, and the contraction amount of a single SMA wire is longer under the same current intensity, so that the driving stroke of the moving element 200 is longer in a pair of SMA wires.

Referring to fig. 15 to 16, in a sixth embodiment, at least two pairs of SMA wires are provided in the same SMA wire group. So configured, the driving force of a single set of SMA wire sets on the moving element 200 can be increased. Specifically, the arrangement manner of the first SMA wire group 310 is also taken as an example. The first SMA wire group 310 is provided with two pairs of SMA wires, that is, the first SMA wire 311 and the second SMA wire 312 are both provided with two SMA wires, and more specifically, the two pairs of SMA wires are provided side by side in the first direction, or alternatively, the two pairs of SMA wires may be provided side by side in the third direction. The same applies to the second SMA wire set 320, which is not described herein. It should be understood that, in the same SMA wire group, three or more pairs of SMA wires may be provided, and the SMA wires are not limited to this.

Referring to fig. 1 to 16, in order to facilitate the electrical connection arrangement of the SMA wires, connection pads 400 are provided on the moving element 200 and the support base, the connection pads 400 are electrically connected to the controller, and both ends of each SMA wire are connected to the connection pads 400. It should be understood that the connecting plate 400 is made of a conductive material, such as a metal material, and the SMA wire and the connecting plate 400 may be welded or bonded by a conductive adhesive. When assembling the SMA wire, firstly, the two ends of the SMA wire are fixedly connected with the connecting sheet 400, and then the connecting sheet 400 is connected with the moving element 200 and/or the supporting structure 100, because the contact area of the connecting sheet 400 and the moving element 200 and/or the supporting structure 100 is far larger than that of the SMA wire and the moving element 200 and/or the supporting structure 100, so the arrangement is realized, the assembly of the SMA wire is simpler and faster, the assembly precision is easier to control, in addition, the connection of the SMA wire is more stable, the SMA wire is not easy to fall off, and the assembly yield is favorably improved.

Further, referring to fig. 4, in the seventh embodiment, it is to be understood that each connecting piece 400 is connected to one end of each SMA wire. So set up for every SMA line can all independently control.

Generally, as the connecting pieces 400 are electrically connected with the controller, the connecting pieces 400 at two ends of the same SMA wire are at different potential positions, so that a potential difference is formed between the two connecting pieces 400, and a current is generated on the SMA wire, and when the potential difference between the two connecting pieces 400 is changed, the current on the SMA wire is changed along with the change, and the electric control on the SMA wire is further realized.

With this arrangement of the connecting tab 400, each SMA wire can be independently controlled. Whether two SMA wires of the same pair of SMA wires are symmetrically arranged or have the same length, or whether two sets of SMA wires are symmetrically arranged in the first direction, the moving element 200 may be deflected or moved in a certain direction along the main axis a with respect to the support structure 100 by independently controlling the magnitude of the current on each SMA wire.

For example, there may be the following various control modes. By controlling the controller, the potential difference across the connecting pads 400 of the first SMA wire 311 is greater than the potential difference across the connecting pads 400 of the second SMA wire 312, and at the same time, the potential difference across the connecting pads 400 of the fourth SMA wire 322 is greater than the potential difference across the connecting pads 400 of the third SMA wire 321, so that the contraction of the first SMA wire 311 is greater than the contraction of the second SMA wire 312, and the contraction of the fourth SMA wire 322 is greater than the contraction of the third SMA wire 321, and therefore, the moving element 200 deflects toward the side of the principal axis a relative to the support structure 100. Or, the potential difference between the connection pads 400 at the two ends of the first SMA wire 311 is greater than the potential difference between the connection pads 400 at the two ends of the second SMA wire 312, meanwhile, the potential difference between the connection pads 400 at the two ends of the third SMA wire 321 is greater than the potential difference between the connection pads 400 at the two ends of the fourth SMA wire 322, and the potential difference between the connection pads 400 at the two ends of the first SMA wire 311 is equal to the potential difference between the connection pads 400 at the two ends of the third SMA wire 321, so that the mobile element 200 can translate in the second direction relative to the support structure 100.

Referring to fig. 1-3, 5-6, 8-14, in an eighth embodiment, in the same pair of SMA wires, both SMA wires may be provided as a single conductive loop. For example, in the same pair of two SMA wires angled with respect to each other, the two SMA wires are connected to the same connecting pad on the support structure 100 or the moving element 200.

Take the first SMA wire set 310 as an example. The head end 300a of the first SMA wire 311 is separately connected with the connecting piece 400, the head end 300a of the second SMA wire 312 is also separately connected with the connecting piece 400, and the tail end 300b of the first SMA wire 311 and the tail end 300b of the second SMA wire 312 are jointly connected with one connecting piece 400, so that the head end 300a of the SMA wire is connected with the support structure 100, and the tail end 300b of the SMA wire is connected with the moving element 200, when the control circuit of the SMA wire is arranged, the connecting piece 400 arranged on the moving element 200 does not need to be electrically connected with a controller, and the connecting pieces 400 arranged at the head end 300a of the first SMA wire 311 and the head end 300a of the second SMA wire 312 are respectively electrically connected with the controller, thereby realizing the electric control of the SMA wire and simplifying the control circuit arrangement of the connecting pieces 400. It is to be understood that the same is true for the arrangement of the second set of SMA wires 320. In this arrangement, each SMA wire set can only be used to drive the moving element 200 to move in one direction, i.e. the first direction or the opposite direction to the first direction.

Further, it is to be understood that if two or more pairs of SMA wires are provided in the same SMA wire group, the ends 300b of the SMA wires in each pair of SMA wires are connected to the same connecting pad 400, and thus the control circuit configuration of the connecting pad 400 can be simplified in the case of increasing the driving force of the SMA wire structure.

Referring to fig. 6 and 7, in a ninth embodiment, one end of one of the SMA wires in the first SMA wire group 310 is connected to the same connecting pad 400 as one end of one of the SMA wires in the second SMA wire group 310. So configured, the circuit setup between the connection pad 400 and the controller can be simplified.

For example, on the basis of the above-described eighth embodiment, with reference to fig. 6 and 17, it may be configured that: the head end 300a of the first SMA wire 311 and the head end 300a of the third SMA wire 321 are connected to the same connecting piece 400, which connecting piece 400 is referred to as a common connecting piece 410 for the moment. The head ends 300a of the second SMA wire 312 and the fourth SMA wire 322 are individually connected to a connecting piece 400. As can be seen from the foregoing, the circuit configuration between the connection pad 400 and the controller can be simplified by forming a potential difference between the connection pads 400 at both ends of the SMA wire, that is, by generating a current in the SMA wire, and arranging the head end 300a of the first SMA wire 311 and the head end 300a of the third SMA wire 321 in parallel. When the first SMA wire group 310 is required to drive the moving element 200 to move, the controller is controlled to make the connection piece 400 connected with the head end 300a of the second SMA wire 312 at another potential, so that a potential difference is formed between the connection piece 400 connected with the head end 300a of the second SMA wire 312 and the common connection piece 410, and finally the first SMA wire 311 and the second SMA wire 312 are conducted and contracted, so as to drive the moving element 200 to move in the first direction relative to the support structure 100. The same is true for the control of the second SMA wire set 320, which is not described in detail here.

Of course, on the basis of the seventh embodiment, referring to fig. 7 and 17, the head end 300a of the first SMA wire 311 and the head end 300a of the third SMA wire 321 may be connected to the same connecting piece 400, which is referred to as the first common connecting piece 411; the head end 300a of the first SMA wire 311 and the head end 300a of the third SMA wire 321 are connected to the same connecting piece 400, which is referred to as a second common connecting piece 412; also, the end 300b of each SMA wire is individually connected to a connecting piece 400. In use, the controller is controlled to keep the first common connection pad 411 and the second common connection pad 412 at the same potential, and when it is desired to cause different amounts of contraction of the different SMA wires, it is only necessary to cause a different potential difference between connection pad 400 at each end 300b of the SMA wire and the first common connection pad 411 or the second common connection pad 412 to cause the mobile element 200 to move in a first direction or a second direction, or to deflect along the major axis a, relative to the support structure 100.

Referring to fig. 19, it will be appreciated that the SMA actuation mechanism may also be arranged to: an elastic member 500 is disposed between the moving element 200 and the support structure 100, and the elastic member 500 is used for supporting the moving element 200, thereby suspending the moving element 200 relative to the support structure 100. The elastic member 500 connects the moving element 200 and the support structure 100, so that the shaking of the moving element 200 relative to the support structure 100 can be reduced, the moving smoothness of the moving element 200 can be improved, and the moving element 200 can be prevented from colliding with the support structure 100 during moving, especially in the case that only one SMA structure 300 is provided. As for the arrangement form of the elastic member 500, the following embodiments are specifically referred to.

In the tenth embodiment, the elastic member 500 includes four elastic arms, each of which connects the moving element 200 and the support structure 100; further, each elastic arm may be disposed in a curved shape to improve flexibility of each elastic arm in the first direction, so that the movement of the moving element 200 is smoother; furthermore, the elastic member 500 is further provided with a connection ring 540, the connection ring 540 is used for connecting the moving element 200, and one end of each elastic arm is connected to the connection ring 540, so that the elastic member 500 has better integrity and is more convenient to assemble.

In the eleventh embodiment, the elastic member 500 includes three elastic arms, i.e., a first elastic arm 510, a second elastic arm 520 and a third elastic arm 530, which are connected to the moving element 200 and the supporting structure 100. In particular, only one SMA structure 300 is provided as an example. In this embodiment, the connecting line between the moving element 200 and the connecting point of each spring arm is a triangle, and further, the top corner of the triangle is close to the side where the moving element 200 is connected to the SMA wire, and the two bottom corners of the triangle are close to the two opposite sides of the moving element 200. Furthermore, the triangle is an isosceles triangle or an equilateral triangle. Specifically, the first elastic arm 510 is connected to the moving member 200 at the middle portion thereof and to the support structure 100 at both ends thereof, and the second elastic arm 520 and the third elastic arm 530 are connected to the moving member 200 and the support structure 100 at both ends thereof. The elastic member 500 is disposed such that the moving element 200 is driven by only one side, and the acting force of the elastic member 500 on the moving element 200 is more uniform and the moving is more stable. When the SMA structure 300 drives the moving element 200 to move relative to the support structure 100, the deformation of the first elastic arm 510 is greater than the deformation of the second elastic arm 520 and the third elastic arm 530, so as to pull the moving element 200 to move.

Referring to fig. 19, in the twelfth embodiment, the elastic member 500 connects the top surface of the support structure 100 and the top surface of the moving member 200, and/or the bottom surface of the support structure 100 and the bottom surface of the moving member 200. It is understood that only one, preferably, two elastic members 500 may be provided, thereby making the movement of the moving member 200 more smooth.

Referring to fig. 20, a camera module according to an embodiment of the second aspect of the present application includes a lens 600, a photosensitive element, and the SMA actuation mechanism described above. The lens 600 is disposed on the moving element 200, the photosensitive element is disposed on the supporting structure 100, and the SMA actuating mechanism is configured to drive the moving element 200 to drive the lens 600 to move relative to the photosensitive element, so as to implement focusing or anti-shake operation; or, the lens 600 is disposed on the supporting structure 100, the photosensitive element is disposed on the moving element 200, and the SMA actuating mechanism is used to drive the moving element to drive the photosensitive element to move relative to the lens 600, so as to implement focusing or anti-shake operation.

In this embodiment, the moving element 200 is annular, so a circular hole penetrating up and down is formed on the moving element 200, a receiving cavity capable of receiving the moving element 200 is formed in the supporting structure 100, wherein the photosensitive element is disposed at the bottom of the supporting structure 100, the lens 600 is disposed in the circular hole of the moving element 200, and light can pass through the lens 600 and irradiate on the photosensitive element at the bottom of the supporting structure 100. It will be appreciated that the major axis a is the axis parallel to the circular aperture.

When the SMA actuation mechanism adopts the solution of any of the above embodiments, that is, the moving element 200 can be translated in the first direction or the second direction or deflected to the side of the main axis a relative to the support structure 100 under the drive of the SMA structure 300. When the moving element 200 moves in a first direction relative to the supporting structure 100, the lens 600 moves closer to or away from the photosensitive element in the first direction, and at this time, the camera module performs a focusing operation; when the moving element 200 translates along the second direction relative to the supporting structure 100, the lens 600 translates along the second direction relative to the photosensitive element, and at this time, the camera module performs an anti-shake operation along a single direction; when the moving element 200 is deflected toward the main axis a relative to the supporting structure 100, the camera module performs an anti-shake operation.

The embodiments of the present application have been described in detail with reference to the drawings, but the present application is not limited to the embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the gist of the present application.

Claims (16)

1. An SMA actuation mechanism, comprising:

a support structure having a height direction that is a first direction;

a moving element formed with a gap from the support structure, the moving element being movable relative to the support structure;

the SMA structure comprises a first SMA wire group and a second SMA wire group which are arranged in a first direction; each SMA wire group comprises at least one pair of SMA wires arranged at an included angle; each SMA wire in the SMA structure is fixedly connected with one side of the moving element and the supporting structure; the SMA structure is used for driving the moving element to move relative to the supporting structure at least along a first direction and a reverse direction.

2. The SMA actuation mechanism of claim 1, wherein: in each SMA wire group, two SMA wires which are arranged in the same pair and form an included angle with each other are symmetrically arranged.

3. The SMA actuation mechanism of claim 2, wherein: the first SMA wire group and the second SMA wire group are arranged asymmetrically.

4. The SMA actuation mechanism of claim 1, wherein: and the two groups of SMA wire groups are symmetrically arranged.

5. The SMA actuation mechanism of claim 1, wherein: in each SMA wire group, two SMA wires which are arranged in the same pair at an included angle have different lengths.

6. An SMA actuation mechanism according to any one of claims 1 to 5, wherein: in each SMA wire group, two SMA wires which are arranged in the same pair and form an included angle with each other are arranged in a crossed manner.

7. The SMA actuation mechanism of claim 1, wherein: and at least two pairs of the SMA wires are arranged in the same SMA wire group.

8. The SMA actuation mechanism of claim 1, wherein: and a plurality of connecting sheets used for being electrically connected with a controller are arranged on the supporting structure and the moving element, and two ends of each SMA wire are connected with the connecting sheets.

9. The SMA actuation mechanism of claim 8, wherein: each connecting piece is correspondingly connected with one end of each SMA wire.

10. The SMA actuation mechanism of claim 8, wherein: the same pair of two SMA wires forming an included angle with each other is connected to the same connecting piece on the supporting structure or the moving element.

11. The SMA actuation mechanism of claim 8, wherein: one end of one of the SMA wires on the first SMA wire group and one end of one of the SMA wires on the second SMA wire group are connected to the same connecting piece.

12. The SMA actuation mechanism of claim 1, wherein: an elastic piece is arranged between the moving element and the supporting structure and used for supporting the moving element.

13. The SMA actuation mechanism of claim 12, wherein: the elastic member connects the support structure top surface and the moving element top surface, and/or the elastic member connects the support structure bottom surface and the moving element bottom surface.

14. The utility model provides a camera module which characterized in that: comprising a lens, a light sensitive element and an SMA actuation mechanism as claimed in any one of claims 1 to 13.

15. The camera module of claim 14, wherein: the lens is arranged on the moving element, the photosensitive element is arranged on the supporting structure, and the SMA actuating mechanism is used for driving the moving element to drive the lens to move relative to the photosensitive element, so that focusing or anti-shaking operation is realized.

16. The camera module of claim 14, wherein: the lens is arranged on the supporting structure, the photosensitive element is arranged on the moving element, and the SMA actuating mechanism is used for driving the moving element to drive the photosensitive element to move relative to the lens, so that focusing or anti-shaking operation is realized.

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