WO2021134850A1

WO2021134850A1 - Actuation apparatus and method for controlling sma actuator wire

Info

Publication number: WO2021134850A1
Application number: PCT/CN2020/073109
Authority: WO
Inventors: 托米·林图洛蒂
Original assignee: 诚瑞光学(常州)股份有限公司
Priority date: 2019-12-30
Filing date: 2020-01-20
Publication date: 2021-07-08
Also published as: CN111158102A; CN111158102B

Abstract

Provided are an actuation apparatus and a method for controlling an SMA actuator wire, wherein same relate to the technical field of electronic devices. The actuation apparatus provided in the present application comprises: a first support structure and a second support structure arranged spaced apart from each other to form a motion space; a movable element accommodated in the motion space; an SMA actuator wire for driving the movable element to move in the motion space; and a detection element for detecting movement information and transmitting same to a control circuit to adjust an energized state of the SMA actuator wire, such that the SMA actuator wire is in a loose state after driving the movable element to be fixed to the second support structure. The technical problem in the prior art of an SMA actuator wire being prone to failure when colliding with a lens or when the lens falls is alleviated.

Description

Actuating device and method for controlling SMA actuator wire

Technical field

This application relates to the technical field of electronic equipment, in particular to an actuating device and a control SMA (Shape Memory Alloy, shape memory alloy) actuator wire method.

Background technique

Recently, in addition to portable cameras, portable terminals similar to smartphones and tablet computers are also equipped with high-performance lens driving devices.

In the prior art, various types of SMA actuation devices are used to provide position control of the movable element. In such devices, the SMA actuator wire is connected between the movable element and the supporting structure under tension. The SMA actuator wire is advantageous as an actuator in such a device, especially due to its high energy density, which means that the SMA actuator that needs to apply a given force has a relatively small size.

As the imaging sensor becomes larger and larger, the lens will become larger and heavier. Therefore, a stronger SMA actuator wire is required. However, the use of a thicker SMA actuator wire will make the brake slower and slower. The larger, thinner SMA actuator wire has good performance, but when the lens is impacted or the lens is dropped, the SMA actuator wire is easily disconnected or malfunctions.

technical problem

The present application provides an actuating device and a method for controlling the SMA actuator wire, so as to alleviate the technical problem that the SMA actuator wire is prone to malfunction when the lens is collided or the lens is dropped in the prior art.

Technical solutions

The first aspect of the present application provides an actuation device, including:

The first supporting structure and the second supporting structure are arranged at intervals to form a movement space;

The movable element is housed in the movement space;

The SMA actuator wire includes a first fixed end and a second fixed end that are fixed to the first support structure and spaced apart from each other, a third fixed end fixedly connected to the movable element, a third fixed end connected to the first fixed end, and The first connecting section of the third fixed end and the second connecting section connecting the second fixed end and the third fixed end are used to drive the movable element to move in the movement space;

Detection element, used to detect movement information;

The control element is used to receive the movement information and adjust the energized state of the SMA actuator wire, so that the SMA actuator wire drives the movable element to be slack after being fixed to the second support structure status.

In a possible design, the detection element is an accelerometer; the movement information includes acceleration information.

In a possible design, the detection element is a gyroscope; the movement information includes angular velocity information.

In a possible design, the detection element is a displacement sensor; the movement information includes displacement information.

In a possible design, the movable device includes:

The lens assembly includes one or more lenses.

In a possible design, the lens assembly includes a lens holder: one or more of the lenses are movably arranged on the lens holder.

The second aspect of the present application provides a method for controlling the SMA actuator wire,

The SMA actuator wire is respectively fixed with the first support mechanism and the movable element;

Provide detection elements for detecting movement information;

Providing a control element for adjusting the energized state of the SMA actuator wire;

When the detection element detects the movement information and transmits it to the control element, the control element adjusts the energization state of the SMA actuator wire so that the SMA actuator wire drives the movable element to be fixed to the The second support structure is in a relaxed state.

Further, the SMA actuator wire includes a first fixed end, a second fixed end, and a third fixed end;

The first fixed end and the second fixed end are arranged at intervals and are respectively fixed to the first supporting structure;

The third fixed end is fixed to the movable element;

The first fixed end and the third fixed end are connected by a first connecting section;

The second fixed end and the third fixed end are connected by a second connecting section.

Further, the detection element is used to obtain the motion state parameter of the actuating device, and determine whether the actuating device is in a falling state;

When the actuating device is in the falling state, the detection element transmits the falling state information to the control element to make the SMA actuator wire in a power-off state, and the SMA actuator wire drives the The movable element is in a relaxed state after being fixed to the second supporting structure.

Further, the motion state parameter includes displacement, velocity, angular velocity or acceleration.

Further, when the acceleration is equal to the acceleration of gravity, the actuating device is in a falling state.

Beneficial effect

The technical solution provided by this application can achieve the following beneficial effects:

The actuating device provided by the present application detects movement information through the detection element and adjusts the energized state of the SMA actuator wire, so that the SMA actuator wire drives the movable element to be fixed to the second supporting structure in a loose state. The position of the movable element can be changed by changing the energized state of the SMA actuator wire to make it slack or tensioned; when the actuating device is impacted or dropped, the detection element sends a message to make the SMA actuator wire finally Being in a slack state reduces the possibility of disconnection or failure of the SMA actuator wire.

What this application provides should be understood that the above general description and the following detailed description are only exemplary, and cannot limit the application.

Description of the drawings

In order to explain the technical solutions of the embodiments of the present application more clearly, the following will briefly introduce the drawings needed in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative work, other drawings can be obtained from these drawings.

Figure 1 is a schematic structural diagram of the SMA actuator wire in the actuating device in a relaxed state;

Figure 2 is a schematic structural view of the tensioned state of the SMA actuator wire in the actuation device;

Fig. 3 is a flowchart of a method for controlling an SMA actuator wire provided by an embodiment of the application.

Reference signs:

11- The first supporting structure;

12- The second supporting structure;

13- movable components;

21- The first fixed end;

22- The second fixed end;

23-The third fixed end;

31-The first connecting section;

32-Second connection section.

The drawings herein are incorporated into the specification and constitute a part of the specification, show embodiments that conform to the application, and are used together with the specification to explain the principle of the application.

Embodiments of the present invention

In order to better understand the technical solutions of the present application, the following describes the embodiments of the present application in detail with reference to the accompanying drawings.

It should be clear that the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of this application.

The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms of "a", "said" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

It should be understood that the term "and/or" used in this text is only an association relationship describing the associated objects, indicating that there can be three types of relationships, for example, A and/or B can mean that A alone exists, and both A and A exist at the same time. B, there are three cases of B alone. In addition, the character "/" in this text generally indicates that the associated objects before and after are in an "or" relationship.

It should be noted that the “upper”, “lower”, “left”, “right” and other directional words described in the embodiments of the present application are described from the angle shown in the drawings, and should not be construed as implementing the present application. Limitations of examples. In addition, in the context, it should also be understood that when it is mentioned that an element is connected "on" or "under" another element, it can not only be directly connected "on" or "under" the other element, but also It is indirectly connected "on" or "under" another element through an intermediate element.

The actuation device provided by the embodiment of the present application includes: a first support structure 11 and a second support structure 12 spaced apart from each other to form a movement space; the movable element 13 is housed in the movement space; the SMA actuator wire includes a first The first fixed end 21 and the second fixed end 22 of the supporting structure 11 spaced apart from each other, the third fixed end 23 fixedly connected to the movable element 13, and the first connecting section 31 connected to the first fixed end 21 and the third fixed end 23 And the second connecting section 32 connecting the second fixed end 22 and the third fixed end 23 is used to drive the movable element 13 to move in the motion space; the detection element is used to detect the movement information; the control element is used to receive the movement information and adjust The energized state of the SMA actuator wire makes the SMA actuator wire drive the movable element 13 to be fixed to the second supporting structure 12 and then be in a relaxed state.

The movement information is detected by the detection element, and the control element adjusts the energization state of the SMA actuator wire after receiving the movement information. The SMA actuator wire can control the position of the movable element 13 so that the SMA actuator wire drives the movable element 13 After being fixed to the second supporting structure 12, it is in a relaxed state. When the actuating device is impacted or dropped, the detection element sends motion information to the control element, so that the SMA actuator wire is in a power-off state and can be moved After the element 13 is driven and fixed to the second supporting structure 12, the SMA actuator wire is in a relaxed state, which reduces the possibility of disconnection or failure of the SMA actuator wire.

By changing the energized state of the SMA actuator wire so that it is in a relaxed or tensioned state, the position of the movable element 13 can be changed. There can be multiple SMA actuator wires, the ends of which connect the movable element 13 and the first support structure 11 with tension. The SMA actuator wires can be arranged parallel to the direction of movement, or arranged at an angle to the direction of movement.

The actuating device may be a mobile phone, a camera or an OIS module, the movable element 13 may be a lens element, and the actuating device may provide OIS by moving the lens element along the optical axis.

The first support structure 11 or the second support structure 12 includes a support block and a mechanical plug for supporting the movable element 13 and providing a moving space for the movable element 13. In addition, the first support structure 11 or the second support structure may be a base, a support plate, or the like.

The movable element 13 may be a lens element, a lens, or a lens assembly.

It should be noted that SMA is a shape memory alloy. The characteristic of the SMA material is that it undergoes a solid phase change when heated, which causes the SMA material to shrink. At low temperatures, the SMA material enters the martensite phase. At high temperatures, SMA enters the austenite phase, which causes deformation and causes the SMA material to shrink. The SMA actuator wire can be made of any suitable SMA material.

When heated, that is, at a high temperature, the SMA actuator wire shrinks and the movable element 13 moves in the first direction; when it is cooled, that is, at a low temperature, the SMA actuator wire will expand, and the movable element 13 will move along the first direction. Moving in two directions, the second direction is the opposite direction to the first direction.

The control of the SMA actuator wire can be realized by a control circuit, that is, the control element can be a control circuit.

Optionally, based on the information detected by the detection element, the control circuit can selectively drive current to flow through the SMA actuator wire to achieve slack or tension of the SMA actuator wire, thereby controlling the position of the movable element 13; for example, Control the SMA actuator wire to be in the power-off state, and at this time, the SMA actuator wire is driven to a relaxed state after being fixed to the second supporting structure, or the SMA actuator wire is controlled to be in the power-on state. The SMA actuator wire changes from a relaxed state to a tensioned state and is driven to leave the second supporting structure. Among them, the heating can be directly provided by the drive current. The cooling can be achieved by reducing or stopping the driving current, so that the movement of the movable element 13 can be controlled.

As shown in Figure 1, when the actuating device is in the power-off mode, that is, when the power is off, the SMA actuator wire drives the movable element 13 to be fixed to the second support structure 12 and then is in a relaxed state. The SMA actuator The wire is slack, and the movable element 13 is located on top of the second support structure 12.

As shown in FIG. 2, when the actuating device is in the power-on mode, the SMA actuator wire will tension and lift the movable element 13 to disengage the movable element 13 from the second support structure 12. At this stage, the weight of the movable element 13 will affect the SMA actuator line, especially when the camera is in the macro phase. The SMA actuator line is very short and cannot be stretched too much. At this time, if the actuator is impacted or When dropped, the SMA actuator wire is easily disconnected or malfunctions. Therefore, when the actuating device is hit or dropped, the detection element sends a message to the control element to make the SMA actuator wire in a slack state, reducing the possibility of disconnection or failure of the SMA actuator wire.

It should be noted that the control element may be a controller.

In a specific embodiment, the detection element is an accelerometer, which can output an acceleration signal representing the movable element 13 or the actuating device, and the control element adjusts the SMA actuator line after receiving the acceleration information detected by the detection element. The energized state of the SMA makes it in a de-energized state, so that the SMA actuator wire drives the movable element 13 to be fixed to the second supporting structure 12 in a relaxed state. If it is determined based on the acceleration signal that the movable element 13 or the actuating device is in a falling or collision state, the detection element will reduce or stop the drive current driving the SMA actuator wire, so that the SMA actuator wire will be gradually self-tensioned. Slack, reducing the possibility of SMA actuator wire disconnection or failure.

The accelerometer can actually detect the acceleration of the movable element 13 or the actuating device, compare the detected acceleration with the preset acceleration threshold, and if the detected acceleration is equal to or greater than the preset acceleration threshold, then determine the movable element 13 Or the actuating device may fall off.

In a specific implementation, the detection element is a gyroscope, which can output a signal representing the angular velocity of the movable element 13 or the actuating device, so as to be used as a signal whether the actuating device has fallen or received a collision. After the control element receives the angular velocity information detected by the detection element, it adjusts the energized state of the SMA actuator wire to make it in a power-off state, so that the SMA actuator wire drives the movable element 13 to be fixed to the second support structure 12 and then becomes slack status. If it is determined according to the signal output by the gyroscope that the movable element 13 or the actuating device is in a falling or collision state, the detection element will reduce or stop the driving current of the SMA actuator wire to make the SMA actuator wire self-tension The tight state gradually relaxes, reducing the possibility of disconnection or failure of the SMA actuator wire. Among them, the gyroscope can detect the angular velocity of the actuating device in real time, and determine whether the actuating device is in a falling state.

In a specific embodiment, the detection element is a displacement sensor, which can output a signal indicating the displacement of the movable element 13 or the actuating device, so as to be used as a signal whether the actuating device has fallen or received a collision. After the control element receives the displacement information detected by the detection element, it adjusts the energized state of the SMA actuator wire to make it in a power-off state, so that the SMA actuator wire drives the movable element 13 to be fixed to the second support structure 12 and then becomes slack status. If it is determined based on the signal output by the displacement sensor that the movable element 13 or the actuating device is in a falling or collision state, the detection element will reduce or stop the drive current driving the SMA actuator wire to make the SMA actuator wire self-tension The tight state gradually relaxes, reducing the possibility of disconnection or failure of the SMA actuator wire.

In a specific embodiment, the movable device includes a lens assembly, and the lens assembly includes one or more lenses, and the one or more lenses can move along a predetermined axis (such as an optical axis). The lens element may specifically include a lens carrier in the shape of a cylinder, and the lens carrier supports lenses arranged along the optical axis.

In a specific embodiment, the lens assembly includes a lens holder: one or more lenses are movably arranged on the lens holder along the optical axis. The lens can be moved along the optical axis to provide focus.

As shown in FIG. 3, an embodiment of the present application also provides a method for controlling an SMA actuator wire, which includes the following steps:

The first support structure 11 and the second support structure 12 are arranged at intervals to form a movement space;

The SMA actuator wire is fixed to the first supporting mechanism and the movable element 13 respectively;

Provide detection elements for detecting movement information;

When the detection element detects the movement information and transmits it to the control element, the control element adjusts the energization state of the SMA actuator wire, so that the SMA actuator wire drives the movable element 13 to be fixed to the second support structure 12 and then is in a relaxed state .

If the detection element determines that the movable element 13 or the actuating device is in a falling or collision state, the detection element will transmit the falling state information to the control element to adjust the energization state of the SMA actuator wire, so that the SMA actuator wire The self-tensioned state gradually relaxes, reducing the possibility of disconnection or failure of the SMA actuator wire.

In a specific embodiment, the SMA actuator wire includes a first fixed end 21, a second fixed end 22, and a third fixed end 23;

In the above steps, the first fixed end 21 and the second fixed end 22 are spaced apart and fixed to the first supporting structure 11 respectively, and the third fixed end 23 is fixed to the movable element 13;

The first fixed end 21 and the third fixed end 23 are connected by a first connecting section 31, and the second fixed end 22 and the third fixed end 23 are connected by a second connecting section 32.

In a specific embodiment, the detection element is used to obtain the motion state parameter of the actuating device and determine whether the actuating device is in a falling state;

When the actuating device is in the falling state, the detection element transmits the falling state information to the control element to make the SMA actuator wire in a power-off state, and the SMA actuator wire drives the movable element 13 to be fixed to the The second supporting structure 12 is in a relaxed state afterwards.

Relaxation In a specific embodiment, the motion state parameter includes displacement, velocity, angular velocity or acceleration.

In a specific embodiment, when the acceleration is equal to the gravitational acceleration, the actuating device is in a falling state.

Optionally, when the difference between the acceleration and the gravitational acceleration is within a predetermined range, it can be determined that the actuating device is in a falling state.

The above are only preferred embodiments of the application, and are not used to limit the application. For those skilled in the art, the application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this application shall be included in the protection scope of this application.

Claims

An actuating device, characterized in that it comprises:

The first supporting structure and the second supporting structure are arranged at intervals to form a movement space;

The movable element is housed in the movement space;

The SMA actuator wire includes a first fixed end and a second fixed end that are fixed to the first support structure and are spaced apart from each other, a third fixed end fixedly connected to the movable element, a third fixed end connected to the first fixed end, and The first connecting section of the third fixed end and the second connecting section connecting the second fixed end and the third fixed end are used to drive the movable element to move in the movement space;

Detection element, used to detect movement information;

The control element is used to receive the movement information and adjust the energization state of the SMA actuator wire, so that the SMA actuator wire drives the movable element to be slack after being fixed to the second support structure status.
The actuating device according to claim 1, wherein the detection element is an accelerometer;

The movement information includes acceleration information.
The actuating device according to claim 1, wherein the detection element is a gyroscope; and the movement information includes angular velocity information.
The actuating device according to claim 1, wherein the detection element is a displacement sensor; and the movement information includes displacement information.
The actuating device according to any one of claims 1 to 4, wherein the movable device comprises:

The lens assembly includes one or more lenses.
The actuating device according to claim 5, wherein the lens assembly comprises a lens holder: one or more of the lenses are movably arranged on the lens holder.
A method for controlling an SMA actuator wire, characterized in that it comprises the following steps: a first support structure and a second support structure are spaced apart to form a movement space;

The SMA actuator wire is respectively fixed with the first support mechanism and the movable element;

Provide detection elements for detecting movement information;

Providing a control element for adjusting the energized state of the SMA actuator wire;

When the detection element detects the movement information and transmits it to the control element, the control element adjusts the energization state of the SMA actuator wire so that the SMA actuator wire drives the movable element to be fixed to the The second support structure is in a relaxed state.
The method of controlling an SMA actuator wire according to claim 7, wherein the SMA actuator wire includes a first fixed end, a second fixed end, and a third fixed end;

The first fixed end and the second fixed end are arranged at intervals and are respectively fixed to the first supporting structure;

The third fixed end is fixed to the movable element;

The first fixed end and the third fixed end are connected by a first connecting section;

The second fixed end and the third fixed end are connected by a second connecting section.
The method for controlling an SMA actuator wire according to claim 7, wherein the detection element is used to obtain the motion state parameters of the actuating device and determine whether the actuating device is in a falling state;

When the actuating device is in the falling state, the detection element transmits the falling state information to the control element to make the SMA actuator wire in the power-off state, and the The SMA actuator wire drives the movable element to be in a relaxed state after being fixed to the second supporting structure.
The method for controlling an SMA actuator wire according to claim 9, wherein the motion state parameter includes displacement, velocity, angular velocity or acceleration.