Actuator assembly

Abstract

An actuator assembly (1) comprising: a support structure (100) having a first main axis (Z1) defined with respect to the support structure; an intermediate part (200) movable relative to the support structure, having a second main axis (Z2) defined with reference to the intermediate part; and a movable member (300) movable relative to the intermediate member and the support structure. One or more tilt actuation units, each tilt actuation unit configured to apply an actuation force capable of tilting the movable member relative to the support structure about a first tilt axis perpendicular to the first main axis and / or a second tilt axis perpendicular to the second main axis, wherein the first tilt axis and the second tilt axis are non-parallel axes. The assembly also has one or more stops (260, 310) configured to limit axial translation of the movable component relative to the support structure along the first main axis when engaged, and wherein the intermediate component is configured to elastically deform to allow engagement of the one or more stops.

Description

field

[0001] This application relates to an actuator assembly including a support structure, a movable part tiltable relative to the support structure, and an intermediate part (e.g., a leveling frame part) configured to allow the movable part to tilt. Overview

[0002] According to a first aspect of this disclosure, an actuator assembly is provided, comprising: a support structure having a first main axis defined with reference to the support structure; an intermediate member movable relative to the support structure having a second main axis defined with reference to the intermediate member; a movable member movable relative to the intermediate member and the support structure; one or more tilting actuation units, each tilting actuation unit configured to apply an actuating force capable of tilting the movable member relative to the support structure about a first tilting axis perpendicular to the first main axis and / or a second tilting axis perpendicular to the second main axis, wherein the first tilting axis and the second tilting axis are non-parallel axes; and one or more endstops configured to restrict axial translation of the movable member relative to the support structure along the first main axis upon engagement; and wherein the intermediate member is configured to elastically deform to allow engagement of the one or more endstops.

[0003] One or more stops can be configured to prevent intermediate parts from undergoing plastic deformation.

[0004] The actuation unit can be configured to prevent one or more stops from engaging when the movable part is subjected only to the force applied by the actuation unit and the equivalent of 1g of gravity (i.e., "g force" or the force on an object when it is at rest on the Earth's surface).

[0005] When the movable part is subjected only to the force applied by the actuating unit and the g force of 1g, the intermediate part can be configured to elastically deform along the first main axis by no more than 5%, 10%, 20%, 30%, 40%, or 50% of the amount of elastic deformation that the intermediate part must undergo along the first main axis in order to allow one or more stops to engage.

[0006] For example, if the intermediate component is configured to undergo an elastic deformation of 5 mm along the first main axis to reach the stop, then when the movable component is only subjected to the force applied by the actuation unit and the g force of 1 g, the maximum amount of elastic deformation that the intermediate component can undergo along the first main axis toward the stop can be 0.25 mm (5% of 5 mm), 0.5 mm (10% of 5 mm), 1 mm (20% of 5 mm), 1.5 mm (30% of 5 mm), 2 mm (40% of 5 mm), or 2.5 mm (50% of 5 mm).

[0007] Each stop may include a stop surface of a movable component and a stop surface of a support structure, wherein the stop surface of the movable component and the stop surface of the support structure are configured to engage with each other when one or more stops are engaged.

[0008] The intermediate component can be mounted on the supporting structure, and the movable component can be mounted on the intermediate component.

[0009] The actuator assembly may include one or more tethering features configured to hold the intermediate component and the support structure together.

[0010] The actuator assembly may include one or more tethering features configured to hold the intermediate part and the movable part together.

[0011] At least one of the tilting actuation units can be configured to apply an actuating force that enables the movable component to rotate relative to the support structure about a first main axis and / or a second main axis.

[0012] The actuator assembly may include one or more rotary actuation units configured to apply an actuating force that enables the movable component to rotate relative to the support structure about a first main axis and / or a second main axis.

[0013] The one or more rotary actuation units may not be subsets of the one or more tilt actuation units.

[0014] At least one of the actuation units (i.e., at least one of the tilt actuation unit and / or the rotation actuation unit) may include an SMA (shape memory alloy) element configured to generate an actuating force upon actuation (i.e., the at least one of the actuation units is configured to apply an actuating force).

[0015] At least one of the actuation units (i.e., at least one of the tilt actuation unit and / or the rotation actuation unit) may include: a main body portion; a shape memory alloy (SMA) element connected between the main body portion and one of the support structure, intermediate component, and movable component, and configured to apply an input force to the main body portion upon actuation; and a force adjustment element connected between the main body portion and the one of the support structure, intermediate component, and movable component, and configured to adjust the input force to generate an actuating force (i.e., the actuating force applied by the at least one of the actuation units).

[0016] The actuator assembly may include a first support arrangement configured to allow an intermediate component (and a movable component) to tilt relative to the support structure about a first tilting axis, and to constrain the intermediate component to tilt relative to the support structure about a second tilting axis or an axis parallel to the second tilting axis.

[0017] The first support arrangement can be configured to allow intermediate components (and movable components) to rotate about a first main axis relative to the support structure.

[0018] The actuator assembly may include a second support arrangement configured to allow the movable member to tilt relative to the intermediate member about a second tilt axis, and to constrain the movable member to tilt relative to the intermediate member about a first tilt axis or an axis parallel to the first tilt axis.

[0019] The second support arrangement can be configured to allow the movable component to rotate about the second main axis relative to the intermediate component.

[0020] Each of the one or more tilting actuation units can be configured to apply a force to the movable part and / or intermediate part, the force having a component in a first direction along the first main axis.

[0021] The one or more tilting actuation units may include: a first actuation unit and a second actuation unit configured to tilt the movable member and the intermediate member relative to the support structure about a first tilting axis; and a third actuation unit and a fourth actuation unit configured to tilt the movable member relative to the intermediate member and the support structure about a second tilting axis.

[0022] The first and second actuation units may each be configured to apply a force to the movable part and / or the intermediate part, the force having a component in a first direction along the first main axis, and the third and fourth actuation units are each configured to apply a force to the movable part, the force having a component in a second opposite direction along the first main axis. In other words, all tilting actuation units are configured to apply a force to the movable part and / or the intermediate part in substantially the same direction along the first main axis.

[0023] Each tilting actuation unit can be configured to apply the actuating force / its actuating force to the movable part.

[0024] The movable part may include electronic components. The electronic component may be an image sensor. It may also be a transmitter, a display, or a part thereof.

[0025] The movable component may include one or more lenses and / or image sensors.

[0026] The movable component may include an image sensor and a lens assembly configured to focus an image onto the image sensor. Brief description of the attached diagram

[0027] Some embodiments of the invention will now be described by way of example only with reference to the accompanying drawings, in which: Figure 1 It is a schematic perspective view of an actuator assembly including movable parts; Figure 2 yes Figure 1 Schematic perspective exploded view of the actuator assembly; Figure 3 It is along Figure 1 Line III-III crosses Figure 1 A schematic cross-section of the actuator assembly, wherein the movable part is in a first position; Figure 4 It is along Figure 1 Line III-III crosses Figure 1 A schematic cross-section of the actuator assembly, wherein the movable part is in a second position; Figure 5 It is along Figure 1 Line III-III crosses Figure 1 A schematic cross-section of the actuator assembly, in which the movable part is in a third position; Figure 6 It is along Figure 1 Line III-III crosses Figure 1 A schematic cross-section of the actuator assembly, in which the movable part is in the fourth position; Figure 7 This is another schematic diagram of actuator assembly 1 to help understand the operation of the actuator unit of the actuator assembly; Figure 8A and Figure 8B These are perspective views and plan views of the actuation unit, which forms part of the actuator assembly, and Figure 8C This is a plan view of another such actuation unit; Figure 9 It is a schematic plan view of the arrangement of the four actuation units; and Figure 10 It is a schematic perspective view of the arrangement of eight actuation units. Detailed description

[0028] like Figure 1 and Figure 2As shown, according to a first aspect of this disclosure, an actuator assembly 1 is provided, comprising: a support structure 100 having a first main axis Z1 defined with reference to the support structure 100; an intermediate member 200 (e.g., a universal joint member 200) movable relative to the support structure 100 having a second main axis Z2 defined with reference to the intermediate member 200; and a movable member 300 movable relative to the intermediate member 200 and the support structure 100.

[0029] One or more tilting actuation units ( Figure 1 and Figure 2 (Not shown) may be provided and configured to apply an actuating force capable of tilting the movable member 300 relative to the support structure 100 about a first inclined axis X perpendicular to the first main axis Z1 and / or a second inclined axis Y perpendicular to the second main axis Z2. The first inclined axis X and the second inclined axis Y are non-parallel axes.

[0030] The actuator assembly 1 also includes one or more stops 260, 310, each stop including a corresponding stop surface 122, 250, 320, which is configured to restrict axial translation of the movable member 300 relative to the support structure 100 along the first main axis Z1 during engagement.

[0031] The intermediate component 200 is configured to elastically deform to allow one or more stops 260, 310 to engage (with each other).

[0032] This will be discussed in more detail below.

[0033] Movable parts In the embodiments described herein, the movable component 300 has a rectangular structure with stop elements 330 extending laterally from each side 340 of the rectangular structure. Each stop element 330 defines a lower stop surface 320 and an upper stop surface 370.

[0034] The movable part 300 may be made of plastic material, but other materials may be used depending on the application of the actuator assembly 1.

[0035] Support structure The support structure 100 has a rectangular structure arranged to receive and hold the intermediate component 200 and the support structure 100 therein. The support structure 100 includes recessed portions 110 in each side 130, and the recessed portions 110 define corresponding recessed surfaces 120 on two opposite sides, such as... Figure 2As can be seen, the recessed surface 120 is configured to engage with the lower side of the protrusion 270 of the intermediate member 200 opposite to the stop surface 250. Two other opposing recessed portions 110 define a recessed surface including the lower stop surface 122. The side portion 130 has an inner surface 160 that defines an internal cavity 140 in which the movable member 300 and the intermediate member 200 are located.

[0036] Like the movable part 300, the support structure 100 can also be made of plastic material, but other materials can be used depending on the application of the actuator assembly 1.

[0037] intermediate components The intermediate component 200 has a frame structure arranged within the internal cavity 140 of the support structure 100.

[0038] The intermediate component 200 includes four clips 230: one clip is centrally positioned on each side 240 of the intermediate component 200. The clips 230 engage with corresponding notches 150, 350 on the support structure 100 and the movable component 300 to form fasteners 210, 220 connecting the intermediate component 200 to both the support structure 100 and the movable component 300.

[0039] like Figure 1 and Figure 2 As shown, the first pair of fasteners 210 connects the intermediate component 200 to the support structure 100, and the second pair of fasteners 220 connects the intermediate component 200 to the movable component 300. Figure 1 and Figure 2 In the example shown, the first pair of tethers 210 are located at opposite points along the X-axis, while the second pair of tethers 220 are located at opposite points along the Y-axis.

[0040] This tethering ensures that the intermediate components do not leave their original position under impact conditions, such as when actuator assembly 1 falls.

[0041] The intermediate member 200 includes a protrusion 270, which includes a lip portion extending laterally on the intermediate member and configured to engage and mate with a recessed surface 120 of the support structure 100. The protrusion 270 defines a stop surface 250. The stop surface 250 is configured to engage with a corresponding lower stop surface 320 of the movable member 300 to define a stop 260, as will be described in further detail below.

[0042] The intermediate component 200 may be made of a flexible spring metal such as high-strength stainless steel and copper alloys (e.g., beryllium copper or titanium copper). Using such a material ensures that the intermediate component 200 is rigid enough to support the movable component 300 during normal operation, but flexible enough to elastically deform to a certain extent under impact inertial loads, such that the movable component 300 engages with the stop surface 120 of the support structure 100 before the deflected portion of the intermediate component 200 engages with the support structure 100.

[0043] To prevent the intermediate component 200 from exceeding its yield stress, the intermediate component 200 may be formed of a high-strength metal, and the shape of the component may be configured to appropriately minimize stress concentration while maintaining the stiffness level required for proper operation of the actuator assembly 1. This may include keeping the resonant frequency mode above a critical level, or ensuring that the actuator unit is configured not to produce problematic deformation when energized.

[0044] Support arrangement Actuator assembly 1 includes one or more support arrangements 600. These are in Figure 7 It is shown schematically in the middle.

[0045] The first support arrangement can be configured to allow the intermediate component 200 (and the movable component 300) to tilt relative to the support structure 100 about a first tilting axis X, and to constrain the intermediate component 200 to tilt relative to the support structure 100 about a second tilting axis Y or an axis parallel to the second tilting axis Y.

[0046] The first support arrangement can be configured to allow the intermediate component 200 (and the movable component 300) to rotate about the first main axis Z1 relative to the support structure 100.

[0047] The actuator assembly 1 may include a second support arrangement configured to allow the movable member 300 to tilt relative to the intermediate member 200 about a second tilt axis Y, and to constrain the movable member 300 to tilt relative to the intermediate member 200 about a first tilt axis X or an axis parallel to the first tilt axis X.

[0048] The second support arrangement can be configured to allow the movable part 300 to rotate relative to the intermediate part 200 about the second main axis Z2.

[0049] The support arrangement may include, for example, one or more of the following support elements: rolling support elements (such as ball support elements), flexural support elements (i.e., an arrangement of flexural elements or other elastic elements that guide movement), or sliding (i.e., sliding contact) support elements.

[0050] The load borne by the support arrangement 600 is limited to the force required to deform the flexible intermediate component, which is several orders of magnitude smaller than the force required for the support to directly resist the inertial load of the moving component in a typical drop test.

[0051] Actuation unit The actuator assembly 1 includes one or more tilting actuation units 400, which are provided and configured to apply an actuating force capable of tilting the movable member 300 relative to the support structure 100 about a first tilting axis X perpendicular to the first main axis Z1 and / or a second tilting axis Y perpendicular to the second main axis Z2. The first tilting axis X and the second tilting axis Y are non-parallel axes.

[0052] At least one of the tilting actuation units 400 can be configured to apply an actuating force that enables the movable part 300 to rotate relative to the support structure 100 about a first main axis Z1 and / or a second main axis Z2.

[0053] Alternatively, actuator assembly 1 may include one or more rotary actuation units 500 configured to apply an actuating force capable of rotating the movable member 300 relative to the support structure 100 about a first main axis Z1 and / or a second main axis Z2. The one or more rotary actuation units 500 may not be a subset of the one or more tilting actuation units.

[0054] At least one of the actuation units (i.e., at least one of the tilt actuation unit 400 and / or the rotation actuation unit 500) includes a shape memory alloy (SMA) element configured to generate an actuating force upon actuation (i.e., an actuating force applied by at least one of the actuation units).

[0055] It should be understood that at least one of the actuation units 400 and 500 can be, for example, a VCM (voice coil motor) actuation unit or a piezoelectric actuation unit.

[0056] Operation of actuator assembly Figure 3 The intermediate component 200 is shown in its undeformed state. In this state, the movable component 300 is in a first (non-tilted) position relative to the support structure 100. In this first position, the distance D3 between the movable component 300 and the upper stop surface (not shown) of the support structure 100 along the first main axis Z1 is maximized. In this first position, the distance D1 between the movable component 300 and the lower stop surface 122 of the support structure 100 along the first main axis D1 is maximized. In this first position, the distance D2 between the intermediate component 200 and the support structure 100 along the first main axis Z1 is maximized.

[0057] During operation, intermediate component 200 is supported against support structure 100, and movable component 300 is supported on intermediate component 200. This support is provided by support arrangement 600, which may include contact features integrated into any of the contacting components, or may be made via the aforementioned third component.

[0058] The actuation units 400 / 500 and / or the support arrangement 600 can constrain (i.e. reduce or prevent) other degrees of freedom of movement of the movable component 300 relative to the support structure 100. The load borne by the support 600 is limited to the force required to deform the flexible intermediate component 200, which is several orders of magnitude smaller than the force required when the support directly resists the inertial load of the movable component in a typical drop test.

[0059] When using free-rolling ball bearings or rollers, tethers 210 and 220 ensure that they do not become free under impact.

[0060] The actuation unit 400 / 500 and the support arrangement 600 can together support the movable part 300 on the support structure 10.

[0061] like Figure 4 As shown, during a drop event (e.g., when a smartphone including actuator assembly 1 is dropped), the intermediate component 200 can elastically deform such that the movable component 300 engages the lower stop surface 122 of the support structure 100 (making the distance D1 = 0). The stop surfaces 250, 320, and 122 are configured such that when this occurs, the intermediate component 200 does not engage with the support structure 100 (i.e., the distance D2 does not reach 0).

[0062] like Figure 5 and Figure 6 As shown, when the external force applied to the movable part 300 is not significantly large (for example, when the smartphone is only subjected to normal hand shaking from the smartphone user), the intermediate part 200 is configured to elastically deform, but the deformation is not large enough to engage the stop surfaces 122, 320 with each other, that is, the deformation is not large enough to engage the movable part 300 with the lower stop surface and the upper stop surface of the support structure 100 (i.e., the distances D1 and D3 do not reach 0).

[0063] Actuation units 400 and 500 can be configured to prevent one or more stops 260 and 310 from engaging when the movable part 300 is subjected only to the force applied by the actuation units 400 / 500 and a g force of 1g (i.e., the force when the object is at rest on the surface of the earth).

[0064] Optionally, when the movable part 300 is subjected only to the force applied by the actuating units 400, 500 and the g force of 1g, the intermediate part 200 is configured such that the elastic deformation along the first main axis Z1 does not exceed 5%, 10%, 20%, 30%, 40% or 50% of the amount of elastic deformation that the intermediate part 200 must undergo along the first main axis Z1 to allow one or more stops 122, 350, 320 to engage (with each other).

[0065] For example, if the intermediate component 200 is configured to undergo an elastic deformation of 5 mm along the first main axis Z1 to engage one or more stops, then when the movable component 300 is subjected only to the force applied by the actuation unit and the force of 1G, the maximum amount of elastic deformation that the intermediate component 200 can undergo along the first main axis Z1 can be 0.25 mm (5% of 5 mm), 0.5 mm (10% of 5 mm), 1 mm (20% of 5 mm), 1.5 mm (30% of 5 mm), 2 mm (40% of 5 mm), or 2.5 mm (50% of 5 mm).

[0066] Figure 7 This is another schematic diagram of actuator assembly 1 to help understand the operation of actuator units 400 and 500.

[0067] Typically, in an actuator assembly, the movable part 300 can be movable relative to the support structure 100 with up to six degrees of freedom (DOF). In describing the degrees of freedom, the principal axes Z1 and Z2 can also be referred to as the z-axis, and two other axes perpendicular to the principal axes Z1 and Z2 and perpendicular to each other can be referred to as the x-axis and y-axis. The movable part 300 can be movable relative to the support structure in all or any subset of the following degrees of freedom (including only one degree of freedom): -Tx and Ty: Translational movement in the xy-plane. In other words, the movable part 300 can move independently along the x-axis and y-axis. The movable part 300 can move to any position within the xy-plane within its range of motion. Instead of this planar movement, the movable part 300 can be linearly movable, for example, along the x-axis or y-axis.

[0068] -Rx and Ry: Rotational movement (or simply rotation or tilt) about the x-axis and y-axis. In other words, the movable part 300 can rotate about any line perpendicular to the principal axis P. The movable part 300 can rotate to any rotational position (i.e., to any orientation) within its range of motion. Instead of this dual-axis rotation, the movable part 300 can rotate about a single axis (e.g., about the x-axis or y-axis).

[0069] -Tz: Translation along the z-axis. The movable part 300 can move along the z-axis to any translational position within its movement range.

[0070] -Rz: Rotational movement (or simply rotation) about the z-axis. The movable part 300 can rotate to any rotational position (i.e., rotate to any orientation) within its range of motion.

[0071] In some examples, the movable component 300 may be supported, for example, by a support arrangement 600 to allow translational movement (Tx, Ty) in the xy plane and / or rotational movement (Rz) about the z-axis. Translational movement (Tz) along the z-axis and rotational movement (Rx, Ry) about the x and y axes may be constrained. For example, such support may be provided by a support arrangement 600 having a suitable arrangement of ball bearings or sliding bearings that generate supporting forces in the +z direction and an offset arrangement that generates offset forces in the -z direction. Examples of actuator assemblies having such support arrangements are disclosed in WO2013 / 175197A1 and WO2017 / 072525A1, each of which is incorporated herein by reference.

[0072] In some examples, the movable component 300 can be supported to allow tilting (Rx, Ry) about the x and y axes and optionally rotation about the z axis (Rz). Other degrees of freedom of movement (i.e., Tx, Ty, Tz, Rz; or Tx, Ty, Tz) can be constrained. This support can be provided by a support arrangement 600 (e.g., in the form of a constant-level frame). An example of such a support arrangement 40 is disclosed in WO2021 / 209770A1, which is incorporated herein by reference. Alternatively, this support can be provided solely by actuation units 400 / 500, similar to WO2011 / 104518A1, which discloses an actuator assembly having eight SMA lines connecting the support structure 10 and the movable component 300. WO2011 / 104518A1 is incorporated herein by reference.

[0073] Figure 8A A perspective view of examples of actuation units 400 and 500 is shown. Figure 8B A portion of the actuation units 400 and 500 is shown in a plan view.

[0074] exist Figure 8A and Figure 8B A single actuation unit 400 is shown, but it should be understood that the actuator assembly 1 typically has multiple actuation units 400, 500, each of which may include a reference. Figure 8A and Figure 8B The same component described.

[0075] The actuation unit 400 includes a main body portion 401 to which several other components of the actuation unit 400 are connected, as described below. Typically, the main body portion 401 is relatively rigid compared to the other components of the actuation unit and does not deform significantly when the actuation unit 400 is actuated. In some examples, the main body portion 401 is not a separate part of the actuation unit 400. For example, the main body portion 401 may be defined as part of one of the other components of the actuation unit 400, or simply as a connection point between the other components of the actuation unit 400.

[0076] The actuation unit 400 also includes a force-adjusting flexure 402. The force-adjusting flexure 402 is connected between the main body portion 401 and the support structure 100. One end of the force-adjusting flexure 402 is connected to the main body portion 401. The other end of the force-adjusting flexure 402 is connected to the support structure 100, for example, via a foot portion 406. The foot portion 406 is fixed relative to the support structure 100. In the depicted design, the force-adjusting flexure 402 is integrally formed with the foot portion 406 and the main body portion 41, for example, formed from a single sheet of material (such as metal). The force-adjusting flexure 402 allows the main body portion 401 to pivot relative to the support structure 100 about an effective pivot point P. Although the effective pivot point P is at... Figure 8B The pivot point P is shown as being positioned at the center of the force-adjusting flexure 402, but the effective pivot point P can have a different location and does not necessarily have to be located on the force-adjusting flexure 402. This pivoting movement of the main body 401 relative to the support structure 10 initially occurs in a direction substantially perpendicular to the force-adjusting flexure 402.

[0077] The actuation unit 400 also includes an SMA element 404. In this example, the SMA element 404 is an SMA line 404. The SMA line 404 connects between the main body portion 401 and the support structure 100. One end of the SMA line 404 is connected to the support structure 100, for example, via a crimp 415. The other end of the SMA line 404 is connected to the main body portion 401, for example, via a crimp 405.

[0078] The actuation unit 400 also includes a connecting link 403. In this example, the connecting link 403 is a connecting flexure 403. The connecting flexure 403 connects between the main body portion 401 and the movable member 300. One end of the connecting flexure 403 is connected to the main body portion 401. The other end of the connecting flexure 403 is connected to the movable member 300. The connecting link 403 transmits or transfers the actuating force F from the main body portion 401 to the movable member 300. The connecting link 403 is flexible (i.e., deformable) in a direction perpendicular to the actuating force F (or multiple directions). This allows the movable member 300 to move in directions other than those of the connecting flexure 403 and the actuating force F. This may be necessary, for example, in situations where different actuation units 30 cause the movable member 300 to move in different directions.

[0079] In this example, the main body 401, the force-adjusting flexure 402, the connecting flexure 403, and the leg portion 406 are integrally formed, for example, from a single sheet of material (such as metal). In other examples, one or more of these features, if present, may be formed from different parts or materials.

[0080] SMA line 404 is arranged to apply an input force Fi to the body portion 401 during contraction. The input force Fi acts parallel to the length of SMA line 404. Force-adjusting flexure 402 and body portion 401 are arranged to adjust the input force Fi to generate an actuating force F, which is transmitted from body portion 401 to movable member 300 via connecting flexure 403. Specifically, the input force Fi deforms force-adjusting flexure 402, thereby causing body portion 401 to pivot about effective pivot point P. Simply put, force-adjusting flexure 402 and body portion 401 act like levers. Force-adjusting flexure 402 and body portion 401 can adjust the direction and / or magnitude of the input force Fi to generate the actuating force F.

[0081] exist Figure 8A and Figure 8B In the example shown, the connecting flexure 403 is at a 90° angle relative to the SMA line 404. Furthermore, in this example, the force-adjusting flexure 402 is arranged at an angle α of 30° relative to the SMA line 404, and is in a stretched state when the SMA line 404 contracts. Therefore, when the SMA line 404 contracts and the resulting force-adjusting flexure 402 deforms, the main body portion 401 initially moves at an angle of 60° (90°-α) relative to the length of the SMA line 404. Thus, it should be understood that in this example, the force is reduced and the stroke is amplified, while the direction of force / movement is changed by 90°.

[0082] More generally, the change in the direction of the force depends on the angle between the SMA line 404 and the connecting flexure 403. Also more generally, the change in the magnitude of the force depends on the ratio of i) the distance Ds from the effective pivot point P to the line containing the SMA line 404 and ii) the distance Dc from the effective pivot point P to the line containing the connecting flexure 403. Specifically, F / Fi is proportional to Ds / Dc. If the line containing the SMA line 404 is closer to the effective pivot point P than the line containing the connecting flexure 403, the input force Fi is reduced. Simultaneously, the movement of the movable member 300 is amplified, i.e., increased relative to the change in the length of the SMA line 404. Alternatively, if the line containing the SMA line 404 is farther from the effective pivot point P than the line containing the connecting flexure 403, the input force Fi is amplified. Simultaneously, the movement of the movable member 300 is reduced, i.e., decreased relative to the change in the length of the SMA line 404. Therefore, the actuation unit 400 can be configured to amplify the movement caused by the contraction of the SMA line 404 or to amplify the force caused by the contraction of the SMA line 404. The actuation unit 400 can also be configured to change the direction of the input force Fi. In some examples, the actuation unit 400 is configured to change the direction of the input force Fi without changing the magnitude of the force or movement.

[0083] The ratio Ds / Dc depends on the position of the SMA line 404 at the end connected to the main body 401 and the position of the connecting flexure 403 at the end connected to the main body 401. As an example, the connecting flexure 403 can be further connected to... Figure 3 The distance Dc is increased by moving the left side of the main body 401 shown in B, thereby decreasing Ds / Dc and thus increasing the stroke amplification. The ratio Ds / Dc also depends on the orientation of the SMA line 404 and the orientation of the connecting flexure 403. Such orientation can be defined with reference to the force-adjusting flexure 32 (as above) or any suitable reference line. As an example, this can be achieved by making... Figure 8B The SMA line 404 shown is angled so that it extends closer to the effective pivot point P to reduce the distance Ds, thereby reducing Ds / Dc and thus increasing the stroke amplification. In summary, the amount by which the force-adjusting flexure 32 amplifies or reduces the force / stroke of the SMA line 404 can be customized in the following ways: - Adjust the orientation of SMA line 404 (and thus adjust the orientation of input force Fi). - Adjust the position of the connection point between the SMA line 404 and the main body 401 (and thus adjust the position of the input force Fi acting on the main body 401). - Adjust the orientation of the connecting flexure 403 (and thus the orientation of the actuating force F); and / or - Adjust the position of the connection point between the connecting flexure 403 and the main body 401 (and thus adjust the position where the actuating force F is applied to the main body 401).

[0084] In some examples, at least one actuation unit 400 (preferably each actuation unit 400) is configured such that the force-adjusting flexure 32 and the main body portion 401 amplify the contraction of the SMA line 404. For example, such amplification factor can be greater than 1.5, preferably greater than 2, and more preferably greater than 3. Therefore, in Figure 3 A and Figure 3 In the example shown in B, the angle α between the SMA line 404 and the force-adjusting flexure 32 can be in the range of 0 to 45 degrees, preferably in the range of 13 to 40 degrees. However, typically, the angle α can have other values, and the connection point between the SMA line 404 and / or the connecting flexure 403 and the body portion 401 can be adjusted to achieve the desired amplification.

[0085] As mentioned above, in Figure 3 A and Figure 3 In the example shown in B, the connecting flexure 403 forms an angle of approximately 90 degrees relative to the SMA line 404. This allows the actuating unit 400 to fold compactly around the corner of the movable part 300. The angle between the connecting flexure 403 and the SMA line 404 can be in the range of 70 to 110 degrees, preferably in the range of 80 to 100 degrees. However, typically, the angle between the connecting flexure 403 and the SMA line 404 can be outside these ranges.

[0086] For example, in Figure 3 In the actuation unit 400 shown in C, the force-adjusting flexure 402, the connecting flexure 403, and the SMA line 404 are substantially parallel to each other.

[0087] In the example above, the actuation unit 400 is arranged in a plane. Specifically, at least when the actuator assembly 2 is in its initial configuration, the SMA line 404, the connecting flexure 403, and the force-adjusting flexure 402 are arranged to extend substantially in a common plane. This allows for a compact configuration of the actuation unit 400. When implemented as a plate, the main body portion 401 can also be arranged to extend in this plane. However, typically, the components of the actuation unit 400 are not necessarily arranged in a common plane. For example, the SMA line 404 and / or the connecting flexure 403 may be angled relative to this plane.

[0088] In the example above, the force-adjusting deflector 402 is in a stretched state when the SMA line 404 contracts. This reduces the risk of buckling of the force-adjusting deflector 402, thereby reducing the risk of damage to actuator assembly 1 and making actuator assembly 1 more reliable. However, the force-adjusting deflector 32 can alternatively be arranged in a compressed state when the SMA line 404 contracts. (See reference...) Figure 8B For example, the force-adjusting flexure 402 can extend downward and to the right from the connection point between the main body 401 and the force-adjusting flexure 402, and is therefore in a compressed state when the SMA line 404 contracts. An arrangement in which the force-adjusting flexure 402 is in a compressed state is disclosed in WO2022 / 084699A1, which is incorporated herein by reference.

[0089] In the example above, the force-adjusting flexure 42 and the SMA line 404 are connected to the support structure 100 at one end, and the connecting flexure 403 is connected to the movable member 300 at one end. Typically, this arrangement can also be reversed, where the force-adjusting flexure 42 and the SMA line 404 are connected to the movable member 300 at one end, and the connecting flexure 403 is connected to the support structure 100 at one end.

[0090] In the above example, the actuation unit 400 includes a connecting link 403 in the form of a connecting flexure 403. The purpose of the connecting link 403 is to allow the movable member 20 to move in a direction perpendicular to the actuating force F. However, typically, the actuation unit 400 does not need to include a connecting link 403 (e.g., in examples where the movable member 300 does not move in a direction perpendicular to the actuating force F). Furthermore, the connecting link 403 can be implemented as a component different from the connecting flexure 403, for example, as a ball bearing or sliding support configured to transmit the actuating force F to the movable member 300 while allowing the movable member 20 to move in a direction perpendicular to the actuating force F. Such an alternative example of the connecting link 403 is disclosed in WO2022 / 084699A1. The connecting link 403 may (or may not) be formed of an SMA line, which may (or may not) be integral with the SMA line 404 and may (or may not) be driven together with the SMA line 404.

[0091] In addition, instead of the force-adjusting flexure 402, the actuator assembly 1 may include different types of force-adjusting elements configured to allow the main body portion 401 to move relative to the support structure 100 as described above. Such force-adjusting elements may include, for example, a rigid member, one end of which is connected to the support structure 100 via a suitable pivoting connection (e.g., a pin joint), and the other end of which is connected to the main body portion 401.

[0092] Figure 8 and Figure 9 A schematic plan view of an example actuator assembly 1 is shown, illustrating the arrangement of four actuation units 400. The four actuation units 400 can apply an actuating force F between the movable member 300 and the support structure 100. The actuating force F is applied to the movable member 300 relative to the support structure 100.

[0093] Figure 9 The four actuation units 400 are arranged in such an arrangement that an actuating force F can be applied to move the movable part 300 relative to the support structure 100 to any position within its range of motion.

[0094] Specifically, the two actuation units 400 (e.g., Figure 9 The top and bottom actuation units are arranged to apply an actuating force F in two opposite directions parallel to the first axis (e.g., the x-axis). The other two actuation units (e.g., Figure 9 The left and right actuating units 400 are arranged to apply an actuating force F in opposite directions to a second axis (e.g., the y-axis) that is parallel to and perpendicular to the first axis. By appropriately changing the difference in actuation amount between the opposing actuating units 400, the movable part 300 can thus move independently along the first and second axes. The opposing actuating forces F are not collinear, but offset from each other in a direction perpendicular to the actuating forces F. Setting the opposing actuating units 400 allows control of the tension in the SMA lines 400 of the respective actuating units 400, thereby allowing for more accurate and reliable positioning of the movable part 20 compared to the case where the actuating units 400 are not opposite each other.

[0095] In some examples, the actuating forces F are not collinear. This allows the arrangement of the actuating units 400 to translate the movable component 300 without applying any net torque to it. Therefore, the movable component 300 can translate within the plane of motion without rotating the movable component 20 within that plane. Typically, the arrangement of the actuating units 400 allows for precise control of the torque or moment of the movable component 20 about the main axes Z1, Z2. Therefore, the actuating units 400 can cause the movable component 20 to rotate (or not rotate) relative to the supporting structure about the main axes Z1, Z2.

[0096] Specifically, the two actuation units 400 (e.g., Figure 4 The top and bottom actuation units are arranged to apply an actuating force F to generate a torque or moment in a first direction (e.g., clockwise) about the main axes Z1, Z2 between the movable part 300 and the support structure 100. Two other actuation units 400 (e.g., Figure 4The left and right actuating units 400 are arranged to apply an actuating force F to generate a torque or moment in a second opposite direction (e.g., counterclockwise) about the main axes Z1, Z2 between the movable part 20 and the support structure 100. This allows the movable part 300 to be rotated by simultaneously increasing or decreasing the tension of the SMA line in either of the two actuating units 400.

[0097] As shown in the figure, two actuation units 400 can be arranged to apply an actuating force F at a corner of the actuator assembly 1. Two other actuation units 400 can be arranged to apply an actuating force F at another opposite corner of the actuator assembly 1. The actuator assembly 1, particularly the movable member 20 and / or the support structure 100, can have a square or rectangular occupying area. Each actuation unit 400 can be disposed on one of the four sides of the actuator assembly 2. In particular, each actuation unit 400 can be bent around a corner of the movable member 300 such that the SMA line 404 and the connecting flexure 403 of each actuation unit 400 extend along adjacent edges of the movable member 300. Therefore, the actuation unit 400 can, for example, be as shown in... Figure 3 A and Figure 3 As configured in B, the four SMA lines 404 of the four actuation units 400 can extend along the four different edges of the movable part 300.

[0098] The arrangement of the actuating force F applied between the movable part 300 and the support structure 100 corresponds to the arrangement of the SMA line 400 described in WO2013 / 175197A1, which is incorporated herein by reference.

[0099] In this example, the actuating force F is perpendicular to the principal axes Z1, Z2 and may be parallel to the plane of movement. However, typically, the actuating force F may be angular relative to the plane of movement. Therefore, the actuating force F may have a component along the principal axes Z1, Z2. This component along the principal axes Z1, Z2 can be resisted by, for example, the support arrangement 600 to provide the movable member 20 with movement in the degrees of freedom allowed by the support arrangement 40. In some examples, it may even be desirable for the actuating force F to have a component parallel to the principal axes Z1, Z2, for example, to apply a load to a sliding or rolling support arranged between the movable member 300 and the support structure 100.

[0100] Although, for illustrative purposes, the arrangement of the actuating unit 400 is described as causing the movable member 300 to move in a plane of movement (e.g., translating along the x and y axes, or rotating about the principal axes Z1, Z2), in other examples, the movable member 20 may move in different ways. For example, the same arrangement of the actuating force F can be used to tilt the movable member 300 relative to the support structure 100 about an axis perpendicular to the principal axes due to appropriate movement constraints provided by the support arrangement 600. For example, the support arrangement 600 may include a plurality of flexures for guiding the movable member 300 to tilt about an axis perpendicular to the principal axes Z1, Z2. An example of such a support arrangement 600 is described in WO2022 / 029441A1, which is incorporated herein by reference.

[0101] Although the actuator assembly 1 is described herein in the context of four actuation units 400, the actuator assembly 1 may typically include fewer actuation units 400. For example, the actuator assembly 1 may include two actuation units 400, such as the two actuation units 400 depicted in the upper left corner of Figure 8. The force applied to the movable part 300 by the two actuation units 400 may be countered by the biasing force of one or more elastic elements, such as springs. Referring to Figure 8, the two actuation units 400 in the lower right corner may be replaced by springs, for example, that apply biasing forces along the corresponding depicted arrows.

[0102] Optionally, the movable part 300 includes electronic components. These electronic components may be an image sensor. They may also be a transmitter, a display, or a portion thereof.

[0103] Optionally, the movable part 300 includes one or more lenses and / or image sensors.

[0104] Optionally, the movable part 300 includes an image sensor and a lens assembly configured to focus an image onto the image sensor.

[0105] Other variations It will be understood that many other variations of the above example may exist.

[0106] SMA The term "shape memory alloy (SMA) element" can refer to any element that includes an SMA. An SMA element can be described as an SMA line. An SMA element can have any shape suitable for the purposes described herein. An SMA element can be elongated and can have a circular cross-section or any other cross-section shape. The cross-section can vary along the length of the SMA element. An SMA element can have relatively complex shapes, such as a helical spring. It is also possible that the length of the SMA element (however defined) can be similar to one or more of the other dimensions of the SMA element. An SMA element can be sheet-like, and such a sheet can be planar or non-planar. An SMA element can be compliant, or in other words, flexible. In some examples, when connected in a straight line between two parts, an SMA element can only apply tension that forces the two parts together. In other examples, an SMA element can bend around a part, and when the SMA element tends to straighten under tension, it can apply a force to the part. An SMA element can be beam-like or rigid, and may be able to apply different forces (e.g., non-tension) to the element. SMA elements may or may not include non-SMA materials and / or components. For example, an SMA element may include an SMA core and a coating of non-SMA materials. Unless the context requires otherwise, the term "SMA element" may refer to any configuration of SMA material that acts as a single actuating element, such that the single actuating element can be individually controlled to generate a force acting on the element. For example, an SMA element may include two or more portions of SMA material arranged mechanically in parallel and / or in series. In some arrangements, an SMA element may be part of a larger SMA element. Such a larger SMA element may include two or more components that can be individually controlled, thereby forming two or more SMA elements. SMA elements may include SMA wires, SMA foils, SMA films, or any other configuration of SMA material. SMA elements may be manufactured using any suitable method, such as by methods involving drawing, rolling, deposition, sintering, or powder melting. SMA elements may exhibit any shape memory effect, such as thermal shape memory or magnetic shape memory, and can be controlled in any suitable manner, such as by Joule heating, another heating technique, or by applying a magnetic field.

Claims

1. An actuator assembly, comprising: A support structure having a first principal axis defined with reference to the support structure; An intermediate component, the intermediate component being movable relative to the support structure, the intermediate component having a second main axis defined with reference to the intermediate component; A movable component, which is movable relative to the intermediate component and the support structure; One or more tilt actuation units, each tilt actuation unit being configured to apply an actuating force capable of tilting the movable component relative to the support structure about a first tilt axis perpendicular to the first main axis and / or a second tilt axis perpendicular to the second main axis, wherein the first tilt axis and the second tilt axis are non-parallel axes; and One or more stops are configured to restrict axial translation of the movable member relative to the support structure along the first main axis during engagement; and The intermediate component is configured to elastically deform to allow the one or more stops to engage.

2. The actuator assembly of claim 1, wherein, The one or more stops are configured to prevent the intermediate component from undergoing plastic deformation.

3. The actuator assembly of claim 1 or 2, wherein, The actuation unit is configured to prevent the one or more stops from engaging when the movable part is subjected only to the force applied by the actuation unit and a gravity equivalent to 1g.

4. An actuator assembly according to any preceding claim, wherein, When the movable component is subjected only to the force applied by the actuating unit and a force of 1g, the intermediate component is configured to elastically deform along the first main axis by no more than 5%, 10%, 20%, 30%, 40%, or 50% of the amount of elastic deformation that the intermediate component must undergo along the first main axis to allow the engagement of the one or more stops.

5. An actuator assembly according to any preceding claim, wherein, Each stop includes a stop surface of the movable component and a stop surface of the support structure, wherein the stop surfaces are configured to engage with each other when one or more stops are engaged.

6. The actuator assembly according to any of the preceding claims, wherein, The intermediate component is mounted on the support structure, and the movable component is mounted on the intermediate component.

7. The actuator assembly according to any of the preceding claims, comprising one or more tethering features configured to hold the intermediate component and the support structure together.

8. The actuator assembly according to any of the preceding claims, comprising one or more tethering features configured to hold the intermediate component and the movable component together.

9. The actuator assembly according to any of the preceding claims, wherein, At least one of the tilting actuation units is configured to apply an actuating force that enables the movable component to rotate relative to the support structure about the first main axis and / or the second main axis.

10. The actuator assembly according to any of the preceding claims, comprising one or more rotary actuation units configured to apply an actuating force capable of rotating the movable member relative to the support structure about the first main axis and / or the second main axis.

11. The actuator assembly according to any of the preceding claims, wherein, At least one of the actuation units includes an SMA (shape memory alloy) element configured to generate the actuating force upon actuation.

12. The actuator assembly according to any of the preceding claims, wherein, At least one of the actuation units includes: Main body; A shape memory alloy (SMA) element, the SMA element being connected between one of the support structure, the intermediate component, and the movable component and the main body portion, and configured to apply an input force to the main body portion upon actuation; and A force adjustment element is connected between one of the support structure, the intermediate component, and the movable component and the main body portion, and is configured to adjust the input force to generate the actuating force.

13. The actuator assembly according to any of the preceding claims, comprising a first support arrangement configured to allow the intermediate component to tilt relative to the support structure about a first tilting axis, and constrain the intermediate component to tilt relative to the support structure about a second tilting axis or an axis parallel to the second tilting axis.

14. The actuator assembly of claim 13, wherein, The first support arrangement is configured to allow the intermediate component to rotate about the first main axis relative to the support structure.

15. The actuator assembly according to any preceding claim, comprising a second support arrangement configured to allow the movable member to tilt relative to the intermediate member about a second tilting axis, and constrain the movable member to tilt relative to the intermediate member about a first tilting axis or an axis parallel to the first tilting axis.

16. The actuator assembly of claim 15, wherein, The second support arrangement is configured to allow the movable component to rotate about the second main axis relative to the intermediate component.

17. The actuator assembly according to any of the preceding claims, wherein each of the one or more tilting actuation units is configured to apply a force having a component in a first direction along the first main axis on the movable member and / or the intermediate member.

18. The actuator assembly according to any preceding claim, wherein the one or more tilting actuation units comprise: A first actuation unit and a second actuation unit are configured to tilt the movable component and the intermediate component relative to the support structure about the first tilting axis. And a third actuation unit and a fourth actuation unit, the third actuation unit and the fourth actuation unit being configured to tilt the movable member relative to the intermediate member and the support structure about the second tilt axis.

19. The actuator assembly of claim 18, wherein, The first actuation unit and the second actuation unit are each configured to apply a force having a component in a first direction along the first main axis to the movable component and / or the intermediate component, and the third actuation unit and the fourth actuation unit are each configured to apply a force having a component in a second opposite direction along the first main axis to the movable component.

20. The actuator assembly according to any of the preceding claims, wherein each tilting actuation unit is configured to apply the actuating force to the movable member.

21. The actuator assembly according to any of the preceding claims, wherein, The movable component includes electronic components.

22. The actuator assembly according to any of the preceding claims, wherein, The movable component includes one or more lenses and / or image sensors.

23. The actuator assembly according to any of the preceding claims, wherein, The movable component includes an image sensor and a lens assembly configured to focus an image onto the image sensor.

Images