Rotary actuator based on shape memory alloys

Abstract

This invention provides an actuator assembly that is particularly thin and compact, suitable for use in cameras. The actuator assembly includes a support structure, a drive shaft, and a sheet-formed shape memory alloy (SMA) element. The SMA element includes an actuation portion, at least three power supply portions, and at least three arms. The power supply portions are arranged around the actuation portion and held in place by the support structure. Each arm connects one of the power supply portions to the actuation portion. The drive shaft is coupled to the actuation portion of the SMA element. The SMA element is configured such that a clockwise or counterclockwise sequence of potentials supplied to the power supply portions causes a circumferential movement of the actuation portion, which is converted into axial rotation of the drive shaft.

Description

Technical Field

[0001] This invention generally relates to actuators for mobile phone cameras, and more particularly to actuators for generating rotational movement. Specifically, rotational movement can be used to move one or more optical elements of a mobile phone camera lens. To this end, this invention provides an actuator assembly based on a shape memory alloy (SMA) element. Background Technology

[0002] Cameras are increasingly integrated into electronic devices, especially handheld devices such as mobile terminals and action cameras. Cameras can incorporate telephoto lenses and / or multiple lens groups within a single device. Therefore, advanced optomechanical structures are employed, including long-distance telecentric lenses and optical zoom structures. Integrating these advanced optomechanical structures within electronic devices requires optical element operation within a very small area (e.g., a few millimeters).

[0003] Furthermore, due to the limited internal space of these electronic devices, camera size is an important factor. In this regard, zoom lenses (e.g., lenses called gel lenses or liquid lenses) can be used. These zoom lenses have the advantage of being thin and compact. Summary of the Invention

[0004] In a conventional approach, a stepper motor is used to operate optical components such as lenses. The stepper motor can generate high-speed, low-torque rotary motion, which is then converted into translational movement using various transmission elements (e.g., lead screws, racks and pinions, and planetary gearboxes).

[0005] In another traditional approach, a voice coil motor (VCM) is used to move optical elements within the camera module. The VCM combines a magnet and a yoke with a coil that surrounds the lens and generates a VCM force proportional to the input current. The position of the optical elements can be adjusted using this generated VCM force.

[0006] In another conventional approach, a piezoelectric ultrasonic actuator (also known as a piezoelectric actuator) is used. This piezoelectric actuator can generate ultrasonic vibrations with micrometer-level amplitudes in a controlled manner to move a lens within a camera module. Specifically, a piezoelectric actuator based on a Smooth Impact Drive Mechanism (SIDM) uses a rapidly expanding / contracting piezoelectric element attached to a shaft fitted with a compression gripper. The rapid expansion and slow contraction (or vice versa) of the piezoelectric element causes the gripper to move using a slip-viscous principle. Optical elements can be attached to the gripper.

[0007] However, these traditional methods cannot meet the demand for thin and compact integration into small electronic devices. Specifically, these traditional methods require a considerable amount of space. For example, stepper motors and VMCs have specific cylindrical shapes, lengths, and diameters, which cannot be further reduced to accommodate more compact electronic devices. Furthermore, piezoelectric actuators can cause severe resonant noise defects within their mechanical camera packages, which are typically hollow plastic housing structures. Additionally, operating zoom lenses in an electronic device may require multiple independent actuators, which necessitates even more space and leads to more severe noise defects. Moreover, the piezoelectric actuators are unsuitable for operating zoom lenses because such operations typically require significant forces, such as 200 mN to 300 mN or greater.

[0008] In view of the aforementioned problems and disadvantages of the conventional methods, embodiments of the present invention aim to provide an improved actuator assembly for one or more camera lenses, with the goal of making the actuator assembly thin and compact for easy integration into smaller electronic devices. Specifically, the actuator assembly should have a wireless, flat actuation structure. The actuator assembly should be suitable for operating optical elements in miniature (narrow and thin form factor) imaging systems. Another objective is to reduce the noise and cost of the actuator assembly. Yet another objective is to reduce the assembly difficulty during the manufacture of the actuator assembly.

[0009] These and other objectives are achieved through the various embodiments of the invention described in the appended independent claims. Further implementations of the embodiments of the invention are further defined in the dependent claims.

[0010] The basic concept of the various embodiments of the present invention is to implement the core actuator as a sequentially driven sheet metal forming SMA element, which can generate reasonable torque on the connected drive shaft without the need for an additional mechanical torque converter or audible noise.

[0011] A first aspect of the invention provides an actuator assembly comprising: a support structure, a drive shaft, and a sheet metal shape memory alloy (SMA) element. The SMA element includes: an actuating portion; at least three energy supply portions, each energy supply portion for providing a potential, arranged around the actuating portion and held in place by the support structure; and at least three arms, each arm connecting one of the energy supply portions to the actuating portion. The SMA element is configured such that a clockwise or counterclockwise sequence of potentials provided to the energy supply portions arranged around the actuating portion causes a circumferential movement of the actuating portion. The drive shaft is coupled to the actuating portion such that the circumferential movement of the actuating portion is converted into axial rotation of the drive shaft.

[0012] Specifically, the sheet-formed SMA element can be a single sheet of SMA (i.e., a sheet-like SMA element). Therefore, the sheet-formed SMA element can be molded or cut from the SMA sheet to form its shape, specifically, to form the actuating portion, the power supply portion, and the arm. Furthermore, the actuating portion can be located in the central region of the SMA element. The arm and the power supply portion can be arranged regularly (i.e., uniformly or consistently) around the actuating portion. The actuating portion and the arm can move relative to the support structure.

[0013] It is worth noting that the surfaces of the actuator, the energy supply, and the arm can be arranged in the common plane of the sheet metal SMA element. For example, depending on the voltage, the potential supplied to the energy supply can cause the actuator to perform the annular movement within the common plane of the sheet metal SMA element.

[0014] In this way, the actuator assembly can be constructed to be particularly thin and compact. Furthermore, the actuator assembly is well-suited for use in miniature cameras. Additionally, the axial rotation of the drive shaft can be converted from the toroidal movement in a specific silent manner, thereby reducing noise generated by the actuator assembly.

[0015] Furthermore, compared to the conventional method, the components of the actuator assembly can be relatively simple. Therefore, the cost of manufacturing the actuator assembly can be reduced.

[0016] Optionally, the support structure may be used to provide one or more mechanical coupling interfaces. Specifically, the power supply component can be securely fixed to the support structure via a portion of the mechanical coupling interfaces. Furthermore, the actuator assembly can interact with one or more transmission elements and / or optical elements via a portion of the mechanical coupling interfaces.

[0017] Furthermore, the support structure can be used to provide one or more electrical interfaces, such that the actuator assembly can be controlled by the potential and / or external signals provided through the electrical interfaces.

[0018] Furthermore, the support structure can provide mechanical and / or electrical protection for the sheet metal SMA element and the drive shaft. In other words, the support structure can be liquid-resistant and waterproof, and / or antistatic. Specifically, the support structure can include a monolithic structure. This protects the sheet metal SMA element and the drive shaft from damage caused by one or more of the following: impact, liquid, dust, electrostatic discharge, etc.

[0019] In one implementation of the first aspect, the potential sequence provided to the energy supply section causes the arms corresponding to the energy supply section to contract one by one, thereby causing the annular movement of the execution section.

[0020] It is worth noting that the SMA material used to manufacture the SMA element can have bidirectional shape memory. In other words, the sheet metal SMA element can be a bidirectional shape memory sheet metal SMA element.

[0021] In another implementation of the first aspect, the resistance of each arm may be greater than the resistance of the corresponding energy supply section and the execution section.

[0022] Specifically, the arm may have a higher aspect ratio (i.e., the ratio of the longer / longest side to the shorter / shortest side) than the actuating portion and / or each of the power supply portions. Alternatively, the average length of the arm may be longer than the average length of the actuating portion and / or each of the power supply portions, and / or the average width of the arm may be shorter than the average width of the actuating portion and / or each of the power supply portions.

[0023] It is worth noting that the execution part can be grounded.

[0024] When the potential is applied to each of the energy supply sections, a current can be generated to flow from each of the energy supply sections through each corresponding arm to the (e.g., grounded) execution section. Therefore, due to the greater resistance, each corresponding arm can generate heat, specifically more heat than each of the energy supply sections and the execution section.

[0025] Specifically, the provided potential can be controlled such that only each corresponding arm can be heated to a temperature exceeding the phase transition temperature of the SMA material. In this way, only each corresponding arm can retract. By retracting the arms sequentially, the annular movement of the actuating section can be achieved.

[0026] In another implementation of the first aspect, the execution portion is coupled to the end of the drive shaft at a position eccentric to the rotation axis of the drive shaft.

[0027] In this way, the annular movement of the actuator can be converted into the axial rotation of the drive shaft.

[0028] In another implementation of the first aspect, the actuating portion is coupled to the drive shaft via a cam knob located at an end of the drive shaft that is eccentric to the axis of rotation of the drive shaft.

[0029] In another implementation of the first aspect, each arm may have a curved structure.

[0030] Specifically, the curved structure can be a tortuous shape, a meandering shape, a coiled shape, or a serpentine shape, etc.

[0031] This increases the resistance of each arm. Furthermore, the bending structure facilitates the contraction of each arm, thereby producing the annular movement of the actuating portion.

[0032] In another implementation of the first aspect, the SMA element may include four power supply sections arranged regularly around the execution section.

[0033] Accordingly, the SMA element may also include four arms. The four arms can connect the four power supply sections to the execution section in a one-to-one correspondence.

[0034] Optionally, the four energy supply sections may be located at the four corners of the support structure.

[0035] In another implementation of the first aspect, the support structure may include a housing that accommodates the SMA element. The sidewalls of the housing may include a circuit board comprising a set of contact pads for providing the potential to the energy supply section.

[0036] Optionally, the circuit board may include another contact pad that can be used to provide an electrical ground connection with the execution portion.

[0037] Specifically, the circuit board may be a printed circuit board.

[0038] This eliminates the need for an external circuit board to control the actuator assembly and reduces the space required.

[0039] In another implementation of the first aspect, the sidewall of the housing may include an opening and a flexible printed circuit (FPC) disposed in the opening. The FPC may be connected to the SMA element, providing the SMA element with the electrical ground connection. The FPC may be movable within the opening, allowing the actuating portion to perform the circumferential movement.

[0040] Specifically, the FPC can be connected to the execution section, such that the execution section is grounded.

[0041] In another implementation of the first aspect, the support structure may include: a plurality of first rivets for securing the energy supply portion to the housing and connecting the energy supply portion to the contact pads of the circuit board; and / or second rivets for connecting the FPC to the execution portion.

[0042] Specifically, the first rivet can be used to electrically connect the circuit board to the power supply section. Furthermore, the first rivet can be electrically connected to the set of contact pads on the circuit board. The second rivet can be used to electrically connect the circuit board to the execution section. Furthermore, the second rivet can be connected to the FPC and can be further connected to the other contact pad providing the electrical ground connection.

[0043] In this way, no wiring connection is required to provide electrical connection between the circuit board and the SMA element, thus further reducing the space occupied by the actuator assembly.

[0044] In another implementation of the first aspect, the drive shaft may penetrate at least one sidewall of the housing.

[0045] In this way, the through end of the drive shaft can be used to provide a connection with one or more transmission elements and / or optical elements. Therefore, the actuator assembly can be flexibly used in a variety of applications.

[0046] In another implementation of the first aspect, the circular movement is an elliptical movement, especially a circular movement.

[0047] It is worth noting that the annular movement of the execution part can be a substantially elliptical movement, especially a substantially circular movement.

[0048] In another implementation of the first aspect, the actuator assembly may include a first gear element and a first rack element. The first gear element may be mounted on the drive shaft and may be coupled to the first rack element. The first gear element may be used to convert the axial rotation of the drive shaft into linear movement of the first rack element.

[0049] Specifically, the first gear element can be firmly mounted on the drive shaft, so that there is no relative movement between the drive shaft and the first gear element.

[0050] In another implementation of the first aspect, the first gear element may include at least two parts, wherein the at least two parts have different tooth pitches.

[0051] In this way, axial rotation with a fixed speed can be converted into linear movement with a variable speed. Therefore, the performance of a camera integrating the actuator assembly can be enhanced. Specifically, the camera's focusing speed can be improved. Furthermore, the speed of adjusting the focal length can also be increased.

[0052] In another implementation of the first aspect, the actuator assembly may include one or more second gear elements and one or more second rack elements. The one or more second gear elements may be mounted on the drive shaft. Each of the second gear elements may be coupled to one of the second rack elements, and each second gear element may have one or more gear properties different from the first gear element.

[0053] In this way, the actuator assembly can support the movement of multiple lenses or multiple lens groups using a single actuator structure.

[0054] In another implementation of the first aspect, the actuator assembly may include a rotary screw and a nut. The rotary screw may be mounted on the drive shaft. The nut may be coupled to the rotary screw such that the nut and the rotary screw can rotate relative to each other. The rotary screw may be used to convert the axial rotation of the drive shaft into linear movement of the nut.

[0055] Specifically, the rotating screw can be securely mounted on the drive shaft. The support structure may include a stop structure to prevent the nut from rotating relative to the support structure. Therefore, as the rotating screw rotates with the axial rotation of the drive shaft, the coupled nut can move linearly along the axis of rotation of the drive shaft.

[0056] In this way, the linearly moving nut can be used to pump liquid into a container via a rubber diaphragm or to deform elastic optical elements. Therefore, the actuator assembly is well-suited for operating zoom lenses.

[0057] Furthermore, the particularly thin and compact shape of the actuator assembly facilitates lens integration and results in a flat and compact camera module.

[0058] In another implementation of the first aspect, the actuator assembly may include a bevel gear assembly and a bevel gear. The bevel gear assembly may be mounted on the drive shaft. The bevel gear assembly and the bevel gear may be coupled to each other, and the bevel gear assembly may be used to convert the axial rotation of the drive shaft into rotation of the bevel gear.

[0059] In this way, the actuator assembly can support the retractable protruding camera optics.

[0060] A second aspect of the invention provides a camera module comprising: a movable lens; and an actuator assembly according to the first aspect or any implementation thereof, wherein the movable lens can be moved by axial rotation of the drive shaft of the actuator assembly.

[0061] A third aspect of the invention provides a method for operating an actuator assembly, wherein the actuator assembly includes: a support structure, a drive shaft, and a sheet metal composite (SMA) element. The SMA element includes: an actuating portion; at least three energy supply portions, each of the energy supply portions being disposed around the actuating portion and held in place by the support structure; and at least three arms, each arm connecting one of the energy supply portions to the actuating portion. The method includes: providing a potential sequence, clockwise or counterclockwise, to the energy supply portions disposed around the actuating portion one by one to induce a circumferential movement of the actuating portion. The circumferential movement of the actuating portion is converted into axial rotation of the drive shaft.

[0062] A fourth aspect of the invention provides a method for executing a camera module, wherein the camera module includes a movable lens and an actuator assembly. The method includes moving the movable lens by performing the method according to the third aspect using the actuator assembly, causing axial rotation of the drive shaft. Attached Figure Description

[0063] The above aspects and their implementation will be explained in the following detailed description of specific embodiments, in conjunction with the accompanying drawings.

[0064] Figure 1 An exploded view of an actuator assembly provided in one embodiment of the present invention is shown;

[0065] Figure 2A A schematic diagram of an actuator assembly provided in one embodiment of the present invention is shown;

[0066] Figure 2B A schematic diagram of a drive shaft provided in one embodiment of the present invention is shown;

[0067] Figures 3A to 3D This illustrates a circular movement of the execution portion provided in one embodiment of the present invention;

[0068] Figure 4 A schematic diagram of an SMA element provided in one embodiment of the present invention is shown;

[0069] Figure 5 An exploded view of an actuator assembly provided in one embodiment of the present invention is shown;

[0070] Figures 6A to 6C A schematic diagram of an actuator assembly provided in one embodiment of the present invention is shown;

[0071] Figures 7A to 7C A schematic diagram of an actuator assembly provided in one embodiment of the present invention is shown;

[0072] Figure 8A and Figure 8B A schematic diagram of an actuator assembly provided in one embodiment of the present invention is shown;

[0073] Figure 9A and Figure 9B A schematic diagram of an actuator assembly applied to a lens assembly is shown according to an embodiment of the present invention;

[0074] Figure 10 A schematic diagram of a gear element and a rack element provided in one embodiment of the present invention is shown;

[0075] Figure 11 A schematic diagram of an actuator assembly applied to a lens assembly is shown according to an embodiment of the present invention;

[0076] Figure 12A A schematic diagram of an actuator assembly provided in one embodiment of the present invention is shown;

[0077] Figure 12B A cross-sectional view of an actuator assembly provided in one embodiment of the present invention is shown;

[0078] Figure 13 A schematic diagram of an actuator assembly applied to a zoom lens according to an embodiment of the present invention is shown;

[0079] Figure 14A schematic diagram of an actuator assembly provided in one embodiment of the present invention is shown;

[0080] Figure 15 An embodiment of the present invention is shown. Detailed Implementation

[0081] Various embodiments of the present invention provide solutions for supporting camera modules with narrow and thin profiles. To this end, the present invention proposes a wireless, flat execution structure for operating optical elements on a miniature imaging system. The proposed execution structure can also support the movement of two or more lenses or lens groups via a single drive shaft.

[0082] to this end, Figure 1 An exploded view of an actuator assembly 1000 provided in one embodiment of the present invention is shown schematically. The actuator assembly 1000 is schematically shown in a (Cartesian) coordinate system composed of vertical x-axis, y-axis, and z-axis, as... Figure 1 As shown.

[0083] It should be noted that the attached diagram ( Figures 1 to 14 The units, components, parts, modules and / or devices of the present invention depicted in the figures are schematically shown in each (Cartesian) coordinate system as applicable, each (Cartesian) coordinate system consisting of a vertical x-axis and / or y-axis and / or z-axis.

[0084] Actuator assembly 1000 includes a support structure ( Figure 1 (Not shown in the image), drive shaft 1200, and sheet metal forming SMA element 1100. SMA element 1100 includes: an actuation section 1103, at least three energy supply sections 1101 (as an example, ...), drive shaft 1200, and sheet metal forming SMA element 1100. Figure 1 The diagram shows four energy supply sections 1001a to 1001d, and at least three arms 1102 (as an example). Figure 1 Four arms 1102a to 1102d are shown. Each energy supply section 1101 is used to provide an electric potential. The energy supply sections 1101 are arranged around the execution section 1103 and held in place by a support structure. Each arm 1102 is used to connect one of the energy supply sections 1101 to the execution section 1103 (i.e., each energy supply section 1101 corresponds to one arm 1102). The SMA element 1100 is configured such that a clockwise or counterclockwise sequence of potentials provided to the energy supply sections 1101 arranged around the execution section 1103 causes a circular movement of the execution section 1103.

[0085] Optionally, the sheet-formed SMA element 1100 can be a single (e.g., cut) sheet-like SMA element. Specifically, the sheet-formed SMA element 1100 can have a thin profile. Furthermore, the actuation portion 1103, the power supply portion 1101, and the arm 1102 of the SMA element 1100 can be formed by molding, grinding, cutting, 3D printing, or any other suitable method in the art to produce an SMA with a specific shape.

[0086] Optionally, the actuator 1103 may be located in the central region of the SMA element 1100. The power supply portion 1101 and the arm 1102 may be arranged regularly (i.e., uniformly or consistently) around the actuator 1103. The actuator 1103 and the arm 1102 may be movable relative to the support structure. Specifically, the surfaces of the actuator 1103, the power supply portion 1101, and the arm 1102 may form a common surface of the sheet metal SMA element 1100. Figure 1 As shown, the common surface can be a surface formed by the vertical x-axis and y-axis. The potential (i.e., voltage) supplied to the energy supply section 1101 can cause the execution section 1103 to move in a ring within the common surface of the sheet metal SMA element.

[0087] Optionally, the execution section 1103 may be grounded. Alternatively, the execution section 1103 may include a grounding connector 1104. In this way, when a potential is provided to the energy supply section 1101, a current is generated flowing along the path from the energy supply section 1101 through the arm 1102 to the execution section 1103.

[0088] In one embodiment of the present invention, the resistance of each arm 1102 may be greater than the resistance of the corresponding energy supply section 1101 and execution section 1103.

[0089] Optionally, within the common plane of the sheet metal SMA element, each arm 1102 may have a higher aspect ratio (i.e., the ratio of the longer / longest side to the shorter / shortest side) than the corresponding power supply portion 1101 and actuation portion 1103.

[0090] Optionally or alternatively, each arm 1102 may have a smaller thickness than the corresponding power supply section 1101 and execution section 1103.

[0091] Alternatively or alternatively, arm 1102 can be manufactured using a second SMA material, different from the first SMA material used to manufacture the energy supply section 1101 and the actuation section 1103. The second SMA material may have a lower phase transition temperature than the first SMA material. In this case, the energy supply section 1101, arm 1102, and actuation section 1103 can be welded together accordingly to form a sheet-formed SMA element 1100.

[0092] It should be noted that the holes shown in the power supply section 1101 of the SMA element 1100 can be used for fixing to a support structure. Furthermore, these holes can be used to connect to electronic components, providing potential from the electronic components.

[0093] It should also be noted that, although in Figure 1 The figure exemplarily illustrates four power supply sections 1101a to 1101d and four arms 1102a to 1102d, but this is not intended to limit the invention to four power supply sections and arms. Those skilled in the art will understand that at least three power supply sections 1101 and three arms 1102 may be sufficient to cause annular movement of the execution section 1103. The same applies to all other figures exemplarily illustrating four power supply sections 1101a to 1101d and four arms 1102a to 1102d.

[0094] Figure 2A An actuator assembly according to an embodiment of the present invention is illustrated. The actuator assembly 1000 is built upon... Figure 1 Based on the actuator component 1000 shown. Similarly, Figure 1 The same elements as those in Figure 2 have the same reference numerals and functions. The drive shaft 1200 is coupled to the actuation portion 1103 of the SMA element 1100, such that the annular movement of the actuation portion 1103 is converted into the axial rotation of the drive shaft 1200.

[0095] This allows the actuator assembly 1000 to have a thinner profile, which is beneficial for compact camera modules, especially small cameras.

[0096] Optionally, the length of the drive shaft 1200 can be configurable. The length of the drive shaft 1200 can be adjusted according to the transmission element attached to the drive shaft 1200, as detailed in Figures 7 to 7 below. Figure 14 .

[0097] In one embodiment of the invention, preferably, the execution part 1103 may be coupled to the end of the drive shaft 1200 at a position eccentric to the rotation axis of the drive shaft 1200.

[0098] Figure 2B It shows from another perspective Figure 1 The drive shaft 1200 is shown. The drive shaft 1200 may include a cam knob 1201 disposed at one end of the drive shaft 1200. The cam knob 1201 may be eccentric relative to the axis of rotation of the drive shaft 1200.

[0099] Specifically, the actuator 1103 can be clamped onto the drive shaft 1200 via the cam knob 1201, such as... Figure 2A As shown.

[0100] Figures 3A to 3D An SMA element 1100 of an actuator assembly 1000 according to an embodiment of the present invention is shown. Specifically, Figures 3A to 3B to Figures 3C to 3D The sequence illustrates the generation of the circular movement of the execution section 1103. Similarly, Figure 3 and Figure 1 The same elements in Figure 2 have the same reference numerals and functions. Figures 3A to 3D In this process, the potential sequence provided to the energy supply section 1101 can cause the arms 1102 corresponding to the energy supply section 1101 to contract one by one, thereby causing the execution section 1103 to move in a ring.

[0101] It should be noted that, for the sake of simplicity and clarity, Figures 3A to 3D Only the SMA element 1100 of the actuator assembly 1000 is shown. Furthermore, due to... Figures 3A to 3D From the perspective marked with the x and y axes, drive shaft 1200 may not be visible.

[0102] use Figure 3A As an example: In the first time slot, an electric potential can be supplied to the first energy supply section 1101a. Current can be generated along a path from the first energy supply section 1101a through the first arm 1102a to the execution section 1103. The first arm 1102a can generate heat due to the current, and it has a large (or maximum) resistance in the current path. The heat can activate the SMA material of the first arm 1102a, and the SMA material can transform from an austenitic state to a martensitic state through contraction. In other words, the first arm 1102a can be heated and thus contracted. It is worth noting that although current and heat can also be generated in the first energy supply section 1101a and the execution section 1103, the first energy supply section 1101a and the execution section 1103 may not reach the phase transition temperature due to the lower resistance. Thus, since the first energy supply section 1101a is held fixed by the support structure, the heated and contracted first arm 1102a can drag or pull the execution section 1103 towards the first energy supply section 1101a.

[0103] Similarly, in Figure 3BAt the second time slot shown, a potential can be supplied only to the second energy supply section 1101b, allowing the first arm 1102a to cool and return to its original austenitic state. Simultaneously, the second arm 1102b can retract and can be dragged or pulled towards the second energy supply section 1101b to actuate the execution section 1103. Similarly, in Figure 3C At the third time slot shown, the third arm 1102c can drag or pull the actuator 1103 toward the third energy supply section 1101c. Figure 3D At the fourth time slot shown, the fourth arm 1102d can drag or pull the execution part 1103 toward the fourth energy supply part 1101d.

[0104] It is worth noting that the potential can be provided repeatedly and continuously according to the above sequence. In other words, it can be done as follows: Figures 3A to 3D The diagram illustrates the ability to provide potential in an infinite loop.

[0105] In this way, the clockwise sequence of potentials supplied to the energy supply section 1101 can cause the drive shaft 1200 to rotate clockwise axially. Similarly, the counterclockwise sequence of potentials supplied to the energy supply section 1101 can cause the drive shaft 1200 to rotate counterclockwise axially. For example, Figures 3D to 3C to Figures 3B to 3A The sequence forms a counterclockwise sequence.

[0106] In one embodiment of the invention, the circular movement can be an elliptical movement, especially a circular movement.

[0107] In this way, the actuator assembly 1000 can be used to silently convert the retraction of the SMA element 1100 (specifically, arm 1102) into the axial rotation of the drive shaft 1200. Therefore, the noise generated by the actuator assembly can be reduced.

[0108] Figure 4 An SMA element of an actuator assembly provided according to an embodiment of the present invention is shown. Similarly, Figure 4 and Figure 1 The same elements in Figure 3 have the same reference numerals and functions.

[0109] Each arm 1102 may have, for example Figure 4 The diagram shows a curved structure. In other words, each arm may not be straight. Specifically, the curved structure can be one with more abrupt changes or one with smoother changes.

[0110] Specifically, the curved structure can be as follows: Figure 1 The zigzag shape, or meandering shape, or coiled shape shown, or Figure 4 The snake-like shape shown is an example.

[0111] Figure 5An exploded view of an actuator assembly provided according to an embodiment of the present invention is shown. Similarly, Figure 5 and Figures 1 to 4 The same elements in the figure have the same reference numerals and functions.

[0112] In this embodiment of the invention, the support structure may include a housing 1300 that accommodates the SMA element 1100. The sidewalls of the housing 1300 may include a circuit board 1301, which includes a set of contact pads 1304 for providing a potential to the power supply section. Furthermore, the circuit board may include another contact pad for providing an electrical ground connection. This other contact pad may be arranged together with the set of contact pads on the circuit board 1301.

[0113] Furthermore, the sidewall of the housing 1300 may include an opening 1302 and a flexible printed circuit (FPC) 1303 disposed in the opening 1302. The FPC 1303 may be connected to the SMA element 1100, specifically to the actuation section 1103, to provide an electrical ground connection. The FPC 1303 may be movable within the opening, allowing the actuation section to move in a ring.

[0114] Optionally, FPC 1303 can be connected to grounding connector 1104 of execution section 1103.

[0115] Optionally, the actuator assembly may include a plurality of first rivets 1305. The first rivets 1305 may be used to secure the energy supply section 1101 to the housing 1300. Furthermore, the first rivets 1305 may be connected to a corresponding number of contact pads 1304 to provide a potential to the energy supply section 1101. Specifically, the first rivets 1305 may be connected to a circuit board 1301, and the circuit board 1301 may be used to provide electrical connections from the first rivets 1305 to the contact pads 1304. The corresponding number of contact pads may be the same as the number of energy supply sections 1101.

[0116] Optionally, the actuator assembly 1000 may include a second rivet 1306. The second rivet 1306 may be used to connect the FPC 1303 to the actuation portion 1103. Additionally, the second rivet 1306 may be connected to one of the contact pads 1304 to provide a grounding connection.

[0117] Alternatively, FPC 1301 can be connected to grounding connector 1104 of execution part 1103 by using second rivet 1306.

[0118] In another implementation, the drive shaft 1200 may penetrate at least one sidewall of the housing 1300 to provide connection to the various drive moving elements.

[0119] Figures 6A to 6C A schematic diagram of an actuator assembly provided in one embodiment of the present invention is shown from different perspectives. Similarly, Figures 6A to 6C and Figures 1 to 5 The same elements in the figure have the same reference numerals and functions.

[0120] It should be noted that the dimensions of actuator assembly 1000 are configurable. The dimensions of actuator assembly 1000 can be determined based on the dimensions of the camera module on which the actuator assembly is mounted. Alternatively, the dimensions of the actuator assembly can be determined based on the required torque generated by actuator assembly 1000.

[0121] Figures 7A to 7C A schematic diagram of an actuator assembly provided according to an embodiment of the present invention is shown. Similarly, Figures 7A to 7C and Figure 1 The same elements in Figure 6 have the same reference numerals and functions.

[0122] In this embodiment of the invention, the actuator assembly 1000 may include a first gear element 1400 and a first rack element 1500 (only when...). Figure 7C (As shown in the figure). The first gear element 1400 and the first rack element 1500 can be coupled to each other. The first gear element 1400 can be firmly mounted on the drive shaft 1200 and can be used to convert the axial rotation of the drive shaft 1200 into the linear movement of the first rack element 1500.

[0123] Specifically, the first gear element can be a pinion.

[0124] It should be noted that, in order to clearly show the first rack element 1500, Figure 7C The SMA element is not shown.

[0125] Figure 8A and Figure 8B A schematic diagram of an actuator assembly provided in one embodiment of the present invention is shown from different perspectives. Similarly, Figure 8A and Figure 8B and Figure 1 The same elements in Figure 7 have the same reference numerals and functions.

[0126] In this embodiment of the invention, the SMA element 1100 can be housed within the housing 1300. The drive shaft 1200 can penetrate the side wall of the housing 1300 and can be connected to a first gear element 1400 outside the housing 1300. The first gear element 1400 can also be coupled to a first rack element 1500. Figure 8A and Figure 8B (Not shown in the image).

[0127] Figure 9A and Figure 9B A schematic diagram of an actuator assembly applied to a camera module according to an embodiment of the present invention is shown. Similarly, Figure 9A and Figure 9B and Figure 1 The same elements in Figure 8 have the same reference numerals and functions.

[0128] In this exemplary embodiment of the invention, the camera module 2000 includes a first lens group 2001a and a second lens group 2001b. An optical path can be formed from the first lens group 2001a, through the second lens group 2001b, to the image sensor 2002. Each of the first lens group 2001a and the second lens group 2001b can be moved by each actuator component 1000.

[0129] It can be seen that, specifically from Figure 9B As can be seen, the actuator assembly 1000 is particularly thin and compact, which allows the camera module 2000 to achieve a smaller size.

[0130] Figure 10 A schematic diagram of a gear element and a rack element provided in one embodiment of the present invention is shown.

[0131] In this embodiment of the invention, the gear element 1600 can be attached to the actuator assembly 1000 in the same manner as the first gear element 1400. The gear element may include at least two parts. Each part has a different tooth pitch. Figure 10 As exemplarily shown, the transmission gear element 1600 includes three portions 1601, 1602, and 1603. The first portion 1601 may include a fine pitch, that is, having the smallest pitch length and / or tooth coarseness among all the pitches of the three portions. The second portion 1602 may include a medium-fine pitch. The third portion 1603 may include a coarse pitch, that is, having the largest pitch length and / or tooth coarseness.

[0132] Furthermore, the gear rack element 1700 can be coupled to the gear rack element 1600 and can be applied to the actuator assembly 1000 in the same way as the first gear rack element 1500.

[0133] In this way, the rotation of the drive shaft 1200 with a fixed rotational speed can be converted into the linear movement of the variable speed rack element 1700.

[0134] Figure 11 A schematic diagram of an actuator assembly applied to a camera module according to an embodiment of the present invention is shown. Similarly, Figure 11 and Figures 1 to 10 The same elements in the figure have the same reference numerals and functions.

[0135] In this embodiment of the invention, one or more second gear elements may be attached to the drive shaft 1200. The one or more second gear elements may be coupled to one or more second rack elements in a one-to-one correspondence. The second gear elements may have gear properties different from and / or different from those of the first gear element 1400. Specifically, different gear properties may include different tip diameters, and / or different pitch diameters, and / or different tooth depths, and / or different numbers of teeth, and / or different center distances.

[0136] like Figure 11 As exemplarily shown, actuator assembly 1000 is attached to two gear elements on drive shaft 1200. The two gear elements and their corresponding rack elements can be used to move two lens assemblies 2001b and 2001c, respectively. Optionally, the two gear elements can have different gear properties so as to move the two lens assemblies 2001b and 2001c at different speeds.

[0137] Optionally, one or more second gear elements may include a speed-changing gear element 1600.

[0138] In this way, the actuator assembly can use a single drive shaft (i.e., drive shaft 1200) to drive multiple lens groups, as well as other additional optical elements (e.g., shutter and / or lens aperture). Therefore, the space occupied by the actuator assembly 1000 can be further reduced.

[0139] Figure 12A A schematic diagram of an actuator assembly provided in one embodiment of the present invention is shown. Figure 12B Correspondingly, a cross-sectional view of the actuator component is shown. Similarly, Figure 12A and Figure 12B and Figures 1 to 11 The same elements in the figure have the same reference numerals and functions.

[0140] In this embodiment of the invention, the actuator assembly 1000 may include a rotating screw 1701 and a nut 1702. The rotating screw 1701 may be mounted on the drive shaft 1200, such as... Figure 12B As shown. Nut 1702 can be coupled to rotating screw 1701, such that nut 1702 and rotating screw 1701 can rotate relative to each other. Rotating screw 1701 can be used to convert the axial rotation of the drive shaft into the linear movement 1702 of the nut.

[0141] Specifically, the rotating screw 1701 can be securely mounted on the drive shaft 1200, so that the rotating screw 1701 and the drive shaft 1200 do not rotate relative to each other. The support structure may include a stop structure 1307 for preventing the nut 1702 from rotating relative to the support structure. Therefore, when the rotating screw 1701 rotates together with the axial rotation of the drive shaft 1200 relative to the support structure, the coupled nut 1702 can heel forward or backward along the rotating screw 1701, thereby producing linear movement along the rotational axis of the drive shaft 1200, such as... Figure 12B As shown.

[0142] Figure 13 A schematic diagram of an actuator assembly applied to a zoom lens according to an embodiment of the present invention is shown. Similarly, Figure 13 and Figures 1 to 1 The same elements in 2 have the same reference numerals and functions.

[0143] In this embodiment of the invention, an actuator assembly 1000 having a rotating screw 1701 and a nut 1702 can be used to drive a zoom lens 3000. The zoom lens 3000 (e.g., a gel lens or a liquid lens) can have holes drilled on its top and bottom sides (i.e., a top hole and a bottom hole). Each hole can be sealed with an elastic diaphragm 3001. Liquid can be injected into the inner cavity 3001 of the zoom lens 3000. When no pressure is applied to the elastic diaphragm 3001 on the top hole, incident light can pass through the zoom lens 3000a in an unfocused state from the bottom hole. When the actuator assembly 1000 linearly moves the nut 1702, the nut 1702 can apply external pressure to the elastic diaphragm 3001 on the top hole, and can cause liquid to gush out from the bottom hole. Therefore, the elastic diaphragm sealed on the bottom side can deform and cause the incident light to be focused from the bottom hole.

[0144] Specifically, the variable rotation speed of the drive shaft 1200 can generate different degrees of pressure on the zoom lens 3000, thereby achieving a variable focusing result for the zoom lens 3000.

[0145] Figure 14 A schematic diagram of an actuator assembly provided in one embodiment of the present invention is shown.

[0146] In this embodiment of the invention, the actuator assembly 1000 may include a bevel gear assembly 1800 and a bevel gear 1900. The bevel gear assembly 1800 and the bevel gear 1900 may be coupled to each other. The bevel gear assembly 1800 may be mounted on the drive shaft 1200 and may be used to convert axial rotation of the drive shaft 1200 into rotation of the bevel gear 1800.

[0147] In this way, the actuator assembly 1000 can be used to operate a telephoto lens, such as the optics of a retractable camera.

[0148] Figure 15 A method 100 according to an embodiment of the present invention is shown. Method 100 is used to operate an actuator assembly 1000. Method 100 includes: step 101, in which a potential sequence is provided clockwise or counterclockwise to an energy supply portion arranged around the actuator portion to cause a circular movement of the actuator portion; step 102, in which the circular movement of the actuator portion is converted into an axial rotation of a drive shaft.

[0149] It should be noted that, from the perspective of the aforementioned executor component 1000, the steps of method 100 can have the same functionality and detailed information. Therefore, the corresponding method implementation 100 will not be described in detail here.

[0150] This application has been described in conjunction with various embodiments and implementations as examples. However, based on a study of the drawings, the invention, and the appended claims, those skilled in the art will understand and implement other variations in practicing the claimed invention. In the claims and the description, the word "comprising" does not exclude other elements or steps, and "a" does not exclude a plurality. A single element or other unit may fulfill the function of several entities or items described in the claims. The mere fact that certain measures are described in mutually different dependent claims does not mean that a combination of these measures cannot be used effectively.

Claims

1. An actuator assembly (1000), characterized in that, The actuator assembly (1000) includes: a support structure, a drive shaft (1200), and a sheet metal forming shape memory alloy (SMA) element (1100), wherein, The SMA element (1100) includes: an actuating portion (1103); at least three energy supply portions (1101), each of which is used to provide an electric potential, arranged around the actuating portion (1103) and held in place by the support structure; and at least three arms (1102), each of which connects one of the energy supply portions (1101) to the actuating portion (1103). The SMA element (1100) is configured such that a sequence of potentials supplied clockwise or counterclockwise to the energy supply section (1101) arranged around the execution section (1103) causes a circular movement of the execution section (1103); The drive shaft (1200) is coupled to the actuation part (1103) such that the annular movement of the actuation part (1103) is converted into the axial rotation of the drive shaft (1200).

2. The actuator assembly (1000) according to claim 1, characterized in that, The potential sequence provided to the energy supply section (1101) causes the arm (1102) corresponding to the energy supply section (1101) to contract one by one, thereby causing the annular movement of the execution section (1103).

3. The actuator assembly (1000) according to claim 1 or 2, characterized in that, The resistance of each arm (1102) is greater than the resistance of the corresponding energy supply section (1101) and the execution section (1103).

4. The actuator assembly (1000) according to claim 1 or 2, characterized in that, The actuator (1103) is coupled to the end of the drive shaft (1200) at a position eccentric to the rotation axis of the drive shaft (1200).

5. The actuator assembly (1000) according to claim 1 or 2, characterized in that, The actuator (1103) is coupled to the drive shaft (1200) via a cam knob (1201) located at the end of the drive shaft (1200) that is eccentric to the axis of rotation of the drive shaft (1200).

6. The actuator assembly (1000) according to claim 1 or 2, characterized in that, Each arm (1102) has a curved structure.

7. The actuator assembly (1000) according to claim 1 or 2, characterized in that, The SMA element (1100) includes four power supply sections (1101) arranged regularly around the execution section (1103).

8. The actuator assembly (1000) according to claim 1 or 2, characterized in that, The support structure includes a housing (1300) for accommodating the SMA element (1100), wherein the sidewall of the housing (1300) includes a circuit board (1301) and the circuit board (1301) includes a set of contact pads (1304) for providing the potential to the energy supply section (1101).

9. The actuator assembly (1000) according to claim 8, characterized in that, The sidewall of the housing (1300) includes an opening and a flexible printed circuit FPC (1303) disposed in the opening (1302). The FPC (1303) is connected to the SMA element (1100) to provide an electrical ground connection for the SMA element (1100); The FPC (1303) can move within the opening (1302) so that the execution part (1103) can make the annular movement.

10. The actuator assembly (1000) according to claim 9, characterized in that, The actuator assembly (1000) further includes: A plurality of first rivets (1305) are used to secure the energy supply portion (1101) to the housing (1300) and to connect the energy supply portion (1101) to the contact pads (1304) of the circuit board (1301); and / or The second rivet (1306) is used to connect the FPC (1303) to the execution part (1103).

11. The actuator assembly (1000) according to claim 8, characterized in that, The drive shaft (1200) penetrates at least one side wall of the housing (1300).

12. The actuator assembly (1000) according to claim 1 or 2, characterized in that, The circular movement is an elliptical movement.

13. The actuator assembly (1000) according to claim 1 or 2, characterized in that, The circular movement is a circular movement.

14. The actuator assembly (1000) according to claim 1 or 2, characterized in that, The actuator assembly (1000) further includes: A first gear element (1400) and a first rack element (1500), wherein the first gear element (1400) is mounted on the drive shaft (1200), the first gear element (1400) and the first rack element (1500) are coupled to each other, and the first gear element (1400) is used to convert the axial rotation of the drive shaft (1200) into linear movement of the first rack element (1500).

15. The actuator assembly (1000) according to claim 14, characterized in that, The first gear element (1400) comprises at least two parts, wherein the at least two parts have different tooth pitches.

16. The actuator assembly (1000) according to claim 14, characterized in that, The actuator assembly (1000) further includes: One or more second gear elements and one or more second rack elements, wherein the one or more second gear elements are mounted on the drive shaft (1200), each of the second gear elements is coupled to one of the second rack elements, and each of the second gear elements has one or more gear properties different from the first gear element (1400).

17. The actuator assembly (1000) according to claim 1 or 2, characterized in that, The actuator assembly (1000) further includes: A rotating screw (1701) and a nut (1702) are provided, wherein the rotating screw (1701) is mounted on the drive shaft (1200), and the nut (1702) is coupled to the rotating screw (1701) such that the nut (1702) and the rotating screw (1701) are rotatable relative to each other, and the rotating screw (1701) is used to convert the axial rotation of the drive shaft (1200) into linear movement of the nut (1702).

18. The actuator assembly (1000) according to claim 1 or 2, characterized in that, The actuator assembly (1000) further includes: A bevel gear assembly (1800) and a bevel gear (1900), wherein the bevel gear assembly (1800) is mounted on the drive shaft (1200), the bevel gear assembly (1800) and the bevel gear (1900) are coupled to each other, and the bevel gear assembly (1800) is used to convert the axial rotation of the drive shaft (1200) into the rotation of the bevel gear (1900).

19. A camera module, characterized in that, The camera module includes: a movable lens; and an actuator assembly (1000) according to any one of claims 1 to 18, wherein the movable lens can be moved by axial rotation of the drive shaft (1200) of the actuator assembly (1000).

20. A method (100) for operating an actuator component, characterized in that, The actuator assembly includes: a support structure, a drive shaft, and a sheet metal shape memory alloy (SMA) element, wherein the SMA element includes: an actuating portion; at least three power supply portions arranged around the actuating portion and held in place by the support structure; and at least three arms, each arm connecting one of the power supply portions to the actuating portion; the method includes: A (101) potential sequence is provided to the energy supply section arranged around the execution section in a clockwise or counterclockwise manner to cause the execution section to move in a ring. The annular movement of the execution part is converted into the axial rotation of the drive shaft by the conversion (102).

21. A method for executing a camera module, characterized in that, The camera module includes a movable lens and an actuator assembly, and the method includes: The movable lens is moved by causing axial rotation of the drive shaft by using the actuator assembly to perform the method according to claim 20.

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