Shape memory alloy (SMA) bimorph actuator and method for manufacturing the same

Abstract

This embodiment relates to a shape memory alloy (SMA) actuator with a reduced number of materials required to manufacture the actuator. In some cases, the elements of the SMA actuator include a dielectric material that is placed on the actuator through an injection molding process. In other cases, the SMA actuator may have SMA wires placed above the base of the SMA actuator without using any dielectric material. In the first example, the SMA actuator may include a carriage and a base. The base may include a fixed end fixed to the carriage, a free end, a beam connecting the fixed and free ends, and at least one SMA wire. The SMA actuator may also include an insulator containing a dielectric material that electrically insulates a first set of electrical contacts at the fixed end.

Description

Technical Field

[0001] Embodiments of the present invention relate to the field of shape memory alloy systems. More particularly, embodiments of the present invention relate to the field of shape memory alloy actuators and related methods.

Background Art

[0002] A shape memory alloy (SMA) system can include an actuator or structure that can be used with various components such as a camera lens element as an autofocus drive or an optical image stabilization (OIS) drive. The SMA actuator can be configured to drive in response to the supply of current to the SMA wire. For example, the first end of the SMA wire can be engaged with a fixed end fixed to the base. Further, the second end of the SMA wire can be engaged with a free end configured to move in response to the drive of the SMA wire. For example, the free end can move in the z direction in response to the drive of the SMA wire.

Summary of the Invention

[0003] This embodiment relates to a shape memory alloy (SMA) actuator comprising a limited number of materials used in the manufacture of the SMA actuator. In a first exemplary embodiment, a shape memory alloy (SMA) actuator is provided. The SMA actuator may include a carriage and a base. The base may include a fixed end fixed to the carriage, a free end, a beam connecting the fixed end and the free end, and at least one SMA wire. Each of the at least one SMA wire may be electrically connected to the fixed end at a first set of electrical contacts and to the free end at a second set of electrical contacts. At least one SMA wire may be configured to drive the free end of the base in response to receiving an electric current. The SMA actuator may further include an insulator containing a dielectric material disposed at the fixed end of the base through an injection molding process. The insulator can electrically isolate the first set of electrical contacts at the fixed end of the base.

[0004] In some cases, the carriage engages with the base either through a heat scribing process or by adding adhesive between the carriage and the base. The heat scribing process may involve applying heat to a projection extending from the carriage through a recess formed at the fixed end of the base.

[0005] In some cases, the support portion at the fixed end is removed by a removal process in order to disconnect the first set of electrical contacts at the fixed end. In some cases, the SMA actuator may include a load point containing a carriage and dielectric material. The load point may be injection molded at the free end.

[0006] In some cases, the SMA actuator may include a pair of reinforcing ribs positioned adjacent to a second set of electrical contacts at the free end. The pair of reinforcing ribs may include a dielectric material. The pair of reinforcing ribs may be injection molded at the free end.

[0007] In some cases, the carriage and insulator comprise a single piece made of dielectric material. In some cases, an SMA actuator may include a first joint element injection-molded at the fixed end and a second joint element injection-molded at the free end. The first and second joint elements may include a dielectric material that electrically insulates at least one SMA wire from the base. The beam may be connected at the fixed end via the first joint element and at the free end via the second joint element.

[0008] In some cases, the beam and insulator comprise a single piece made of dielectric material. In some cases, the SMA actuator may be part of a lens assembly as an autofocus actuator or part of an optical image stabilization system.

[0009] In another exemplary embodiment, a method for manufacturing a shape memory alloy (SMA) actuator is provided. The method may include engaging a carriage with a base. The base may include a fixed end fixed to the carriage, a free end, a beam connecting the fixed and free ends, and at least one SMA wire. Each of the at least one SMA wire may be electrically connected to the fixed end at a first set of electrical contacts and to the free end at a second set of electrical contacts. At least two one SMA wires may be configured to drive the free end of the base in response to receiving an electric current. The method may also include placing an insulator at the fixed end of the base via an injection molding process. The insulator comprises a dielectric material and electrically insulates the first set of electrical contacts at the fixed end of the base.

[0010] In some cases, engaging the carriage to the base involves either a heat scribing process that includes applying heat to a projection extending from the carriage through a recess formed in the fixed end of the base, or adding adhesive between the carriage and the base.

[0011] In some cases, the method involves removing the support portion of the fixed end by a removal process in order to disconnect the first set of electrical contacts of the fixed end. In some cases, the method involves positioning a load point containing dielectric material on the free end during the injection molding process.

[0012] In some cases, the carriage is made of a dielectric material and engages with the base during the injection molding process. In some cases, the method includes positioning a first bonding element made of a dielectric material at a fixed end via an injection molding process and positioning a second bonding element at a free end via an injection molding process. The first and second bonding elements can electrically insulate at least one SMA wire from the base. The beam may be connected at the fixed end via the first bonding element and at the free end via the second bonding element.

[0013] In some cases, the beams include dielectric material. The method may also include positioning the beams at fixed and free ends of the base via an injection molding process. In another exemplary embodiment, an SMA actuator is provided. The SMA actuator may include a carriage and a base. The base may include a fixed end fixed to the carriage, a free end, a beam connecting the fixed end and the free end, and at least one SMA wire. Each of the at least one SMA wire is electrically connected to the fixed end at a first set of electrical contacts and to the free end at a second set of electrical contacts. At least one SMA wire may be positioned above the base, except for the first set of electrical contacts and the second set of electrical contacts, to electrically isolate the at least one SMA wire from the base.

[0014] In some cases, at least one SMA wire is coated. In some cases, the SMA actuator may include a first bumper positioned at the fixed end between at least one SMA wire and the fixed end of the base, and a second bumper positioned at the free end between at least one SMA wire and the free end of the base.

[0015] In some cases, the first set of electrical contacts is cast to offset at least one SMA wire from the base. Other features and advantages of embodiments of the present invention will become apparent from the accompanying drawings and the following detailed description.

[0016] Embodiments of the present invention are illustrated in the drawings of the accompanying drawings, not by way of limitation, but by way of example, and in the drawings, like reference numerals indicate like elements.

Brief Description of the Drawings

[0017] [Figure 1] A diagram showing an exemplary conventional SMA bimorph actuator. [Figure 2A] A diagram showing an SMA actuator manufactured according to a first exemplary embodiment. [Figure 2B] A diagram showing an SMA actuator manufactured according to a first exemplary embodiment. [Figure 2C] A diagram showing an SMA actuator manufactured according to a first exemplary embodiment. [Figure 2D] A diagram showing an SMA actuator manufactured according to a first exemplary embodiment. [Figure 2E] A diagram showing an SMA actuator manufactured according to a first exemplary embodiment. [Figure 2F] A diagram showing an SMA actuator manufactured according to a first exemplary embodiment. [Figure 3] A diagram showing an actuator according to a second exemplary embodiment. [Figure 4A] A diagram showing an actuator according to a third exemplary embodiment. [Figure 4B] A diagram showing an actuator according to a third exemplary embodiment. [Figure 4C] A diagram showing an actuator according to a third exemplary embodiment. [Figure 4D] A diagram showing an actuator according to a third exemplary embodiment. [Figure 4E]Figure showing an actuator according to a third exemplary embodiment. [Figure 4F] Figure showing an actuator according to a third exemplary embodiment. [Figure 5A] Figure showing an actuator according to a fourth exemplary embodiment. [Figure 5B] Figure showing an actuator according to a fourth exemplary embodiment. [Figure 5C] Figure showing an actuator according to a fourth exemplary embodiment. [Figure 5D] Figure showing an actuator according to a fourth exemplary embodiment. [Figure 6A] Figure showing an actuator according to a fifth exemplary embodiment. [Figure 6B] Figure showing an actuator according to a fifth exemplary embodiment.

Best Mode for Carrying Out the Invention

[0018] This embodiment relates to a shape memory alloy (SMA) actuator. The SMA actuators described herein may have a compact footprint and produce a high drive height, e.g., movement, in the positive z-axis direction (z-direction), which is referred to herein as z-stroke motion. The SMA actuators described herein may include SMA bimorph actuators. SMA actuators can be used in many applications, such as, but are not limited to, lens assemblies as autofocus actuators, micro-fluidic pumps, sensor shifts, optical image stabilization, and optical zoom assemblies, to mechanically strike two surfaces to produce a vibration sensation, as is commonly found in tactile feedback sensors and devices, and in other systems in which actuators are used. For example, embodiments of the actuators described herein may be used as tactile feedback actuators for use in cellular mobile phones and wearable devices, configured to provide the user with an alarm, notification, warning, or response to a touched area or pressed button. Furthermore, two or more SMA actuators may be used in a system to achieve a larger stroke.

[0019] In some embodiments, the SMA actuator may include a z-stroke greater than 0.4 millimeters (e.g., 0.7 to 1 millimeter). Furthermore, for various embodiments, the SMA actuator may have a height of about 0.4 millimeters or less in the z-direction when the SMA actuator is in its initial drive-stop position. Various embodiments of the SMA actuator, which can be configured as an autofocus actuator in a lens assembly, may have a small footprint that is about 3 millimeters larger than the inner diameter of the lens. According to various embodiments, the SMA actuator may have a footprint that is wide enough to accommodate components including, but not limited to, sensors, wires, traces, and connectors in one direction. According to some embodiments, the footprint of the SMA actuator is 0.5 millimeters larger in one direction, for example, the length of the SMA actuator is 0.5 millimeters longer than its width.

[0020] Figure 1 shows an exemplary prior art SMA bimorph actuator 100. As shown in Figure 1, the actuator 100 may include a base 102 and a carriage 104. Often, the base 102 may be fixed to the carriage 104 as described herein. The carriage 104 can increase the resilience of the actuator 100 by providing support for the base 102.

[0021] The base 102 may include a fixed end 106 and a free end 108. The fixed end 106 can be fixed to the carriage 104, and the free end 108 can be detached from the carriage 104. As will be described in more detail below, the free end 108 can move in the z-stroke direction (e.g., direction D1) in response to supplying current to the SMA wires 110a, 110b.

[0022] The fixed end 106 can be attached to the carriage 104. Furthermore, the beam 112 does not have to be attached to the carriage 104, and, like the free end 108, it is possible for the beam to be lifted away from the carriage.

[0023] As shown in Figure 1, the SMA wires 110a and 110b can extend from the fixed end 106 to the free end 108 of the base 102. Furthermore, the beam 112 can be positioned below the SMA wires 110a and 110b and can connect the fixed end 106 to the free end 108. The SMA wires 110a and 110b can be connected to the base 102 at each end via electrical contacts. For example, at the first end of each SMA wire 110a and 110b, the SMA wires 110a and 110b can be connected to the fixed end 106 at electrical contacts 114a and 114b. Furthermore, at the second end (for example, at the free end 108), the SMA wires 110a and 110b can be connected to the free end 108 at electrical contacts 118a and 118b (for example, through a welding or soldering process).

[0024] The base 102 can be made of a material such as steel or stainless steel. Furthermore, the electrical contacts 114a-b, 118a-b may be made of a material that allows for welding or soldering, such as gold-plated stainless steel. Furthermore, at the free end 106, the dielectric 116 can insulate the electrical contacts 114a-b to prevent current from flowing between the contacts. The dielectric 116 may be made of an insulating material such as polyimide. In some embodiments, a dielectric may be placed between the SMA wires 110a-110b and the beam 112 at the free end 108 to electrically insulate the SMA wires 110a-b from the beam 112.

[0025] In some cases, the actuator may include a three-layer design, where the first layer is made of stainless steel (e.g., forming the base 102), the second layer is made of polyimide (e.g., insulating the electrical contacts), and the third layer is made of gold-plated stainless steel.

[0026] In some embodiments, the actuator may include an alternative design with a reduced number of layers. Actuators including these alternative designs require fewer resources, thus reducing the processing steps for manufacturing actuators such as those described herein.

[0027] In a first exemplary embodiment, an injection molding process can be provided. The injection molding process may include adding dielectric material to the actuator, such as dielectric 116 that insulates circuits 114a-114b in Figure 1, which can insulate the electrical circuit. In some cases, the load point can be injection molded. Furthermore, reinforcing ribs containing injection molded material may be placed at the free end adjacent to the end of the electrical contact.

[0028] In a second exemplary embodiment, the carriage and dielectric can be manufactured through an injection molding process. The base may include a metallic material, and the carriage and dielectric may include a single piece made of injection-molded material.

[0029] In a third exemplary embodiment, the base may be secured to the carriage by a heat scribing or bonding process. In particular, in the third exemplary embodiment, it may not be necessary to add injection-molded material or any dielectric material to insulate the electrical circuit.

[0030] In a fourth exemplary embodiment, a molded bimorph beam offset may be added. In particular, the beam can be attached to the injection-molded part at both the free and fixed ends. The beam may include parts separate from the free and fixed ends of the base.

[0031] In a fifth exemplary embodiment, the beam may include an injection-molded material. In particular, the injection-molded material may include a single part comprising a dielectric at a fixed end, the beam, and a portion arranged around the free end. The carriage may include either a metallic material or an injection-molded material.

[0032] Figures 2A to 2F show SMA actuators 200a to F manufactured according to a first exemplary embodiment. As shown in Figure 2A, actuator 200a may include an injection-molded material as a dielectric 216 at the fixed end and between the SMA wire and the free end. The injection-molded (or dielectric) material may include any of a variety of plastics, thermoplastics, or polycarbonate materials. Exemplary materials for the injection-molded materials described herein may include acrylic (PMMA), liquid crystal polymer (LCP), acrylonitrile butadiene styrene (ABS), nylon polyamide (PA), polycarbonate (PC), polyethylene (PE), polyoxymethylene (POM), polypropylene (PP), polystyrene (PS), thermoplastic elastomer (TPE), thermoplastic polyurethane (TPU), and the like. An injection molding injector may be added to the injection-molded materials described herein.

[0033] In Figure 2B, the actuator 200b may include a carriage provided to connect to a base. The base can be attached to the carriage via a heat scribing or bonding process. A projection 222 extending from the carriage may extend into a recess 220 of the base, allowing the base to be aligned and attached to the carriage. For example, a heat scribing process may heat the projection 222 to distribute projection material around the recess 220 in order to secure the base to the carriage.

[0034] In Figure 2C, the actuator 200c may include a base fixed to the carriage. Furthermore, the support portion of the base (e.g., 218) may be removed through a removal process. By removing the support portion (e.g., along removal line 224) and including injection-molded material in the dielectric, insulation of the electrical contacts is possible to prevent grounding or short circuits of the electrical contacts. Figure 2D shows the actuator 200d with the support portion removed.

[0035] In some embodiments, the load point can include an injection-molded material. Instead of having a formed load point (e.g., 220 as shown at the free end in Figure 1), the load point can consist of a flat metallic material, and the formed load point 228 can be positioned above the flat load point. The formed load point 228 can include a dielectric material via the injection molding process.

[0036] Furthermore, in some embodiments, reinforcing ribs may be placed at the free end. For example, ribs 226a-c may be placed between electrical contacts 214a-b that connect the SMA wire to the free end. The reinforcing ribs can increase the structural support of the connection between the electrical contact and the SMA wire (e.g., welded connection, soldered connection).

[0037] Figure 3 shows an actuator 300 according to a second exemplary embodiment. In the actuator 300 shown in Figure 3, the carriage 304 and dielectric 316 may include injection-molded material. In some cases, the injection-molded material may include a single piece. For example, the injection-molded material may be inserted around the base in such a way that the injection-molded material forms an insulated electrical circuit for the carriage and dielectric. Furthermore, after insertion of the injection-molded material, the support portion of the base may be removed through a removal process.

[0038] Figures 4A to 4F show actuators 400a to 400f according to a third exemplary embodiment. As shown in Figures 4A to 4F, the base can be attached to the carriage without any injection-molded material. For example, in Figure 4A, the SMA wire may include an uncoated wire or a coated wire. If the wire is coated, the coating can insulate the SMA wire from the base. Furthermore, in some cases, there may be no wire bumper separating the SMA wire from the base. The SMA wire can be raised above the base, except for the electrical connections, to insulate the SMA wire from the base.

[0039] In Figure 4B, the base can be attached to the carriage while leaving the base frame 402 intact. The base 402 can be attached to the carriage 404 via a heat scribing or bonding process. In Figure 4C, the support portion of the base 418 can be removed via a removal process. For example, the removal process may include laser removal of the support portion.

[0040] In some cases, the space between the SMA wire and the base may be isolated using one or more bumpers 428a-b. In Figure 4D, a pair of bumpers 428a-b may be added below the SMA wire to electrically insulate the SMA wire from the bumper. The wire bumper (or pick-and-place bumper) may include a thin insulating material that can be bonded to the base.

[0041] In some cases, the carriage may include a metal material that allows for welding attachment of the base. For example, in Figure 4E, the fixed end of the base may be welded to the carriage. In some cases, the SMA wire may be offset by wire mounting pads. For example, in Figure 4F, pads 430a-b may be cast or insert molded to lift (or offset) the SMA wire to insulate it from the base.

[0042] Figures 5A to 5D show an actuator according to a fourth exemplary embodiment. For example, the base may include an insert-molded bimorph beam offset 512. For example, in Figure 5A, the beam 512 may be connected to a plurality of molded joints 534a to b that form the beam relative to the base. In some cases, the base may include an outer frame 532. The outer frame 532 may include additional material used to fabricate and support the beam 512. In some cases, three bimorph parts, such as the base, beam, and tip, may be tabbed to the outer frame during fabrication.

[0043] In some cases, the outer frame 532 can be removed. For example, in Figure 5B, the outer frame can be removed while leaving the beams engaged with the molded joints 534a and 534b. In some cases, the actuator may include a molded load point 528 comprising dielectric material from the injection molding process.

[0044] In some cases, the outer frame 512 may be located below the base. For example, Figure 5C shows a beam 512 below the base of the actuator 500c. Furthermore, the beam 512 may be connected to molded joints 534a-b.

[0045] In some cases, the beam 512 may include a single piece of metal (e.g., stainless steel). For example, as shown in Figure 5D, the beam 512 may include a portion (e.g., 536) that penetrates the welded joints 534a and 534b.

[0046] Figures 6A and 6B show actuators 600a and 600b according to a fifth exemplary embodiment. For example, as shown in Figure 6A, actuator 600a may include a beam 612 containing injection-molded material. The dielectric 616 and beam 612 can form a single piece of injection-molded material. The injection-molded material may also be placed at the free end. The fixed and free end portions may be exposed from the injection-molded material to allow electricity to flow between the electrical contacts and the SMA wire, as described herein.

[0047] In some cases, multiple tabs 636a-c containing metal may be removed. Tabs 636a-c may be used for the manufacture of fixed-end and free-end portions of actuators as described herein.

[0048] As shown in Figure 6B, tabs 636a-c may be removed. Furthermore, actuator 600b may be fixed to the carriage as described herein. In a first exemplary embodiment, a shape memory alloy (SMA) actuator is provided. The SMA actuator may include a carriage (e.g., 104) and a base (e.g., 102). The base may include a fixed end (e.g., 106) fixed to the carriage, a free end (e.g., 108), a beam (e.g., 112) connecting the fixed and free ends, and at least two SMA wires (e.g., 110a-b). Each of the at least two SMA wires may be electrically connected to the fixed end at a first set of electrical contacts (e.g., 114a-b) and electrically connected to the free end at a second set of electrical contacts (e.g., 118a-b). The at least two SMA wires may be configured to drive the free end (e.g., 108) of the base in response to receiving an electric current. The SMA actuator may further include an insulator (e.g., 116, 216) containing a dielectric material disposed at the fixed end of the base through an injection molding process. The insulator can electrically isolate the first set of electrical contacts at the fixed end of the base.

[0049] In some cases, the carriage engages with the base either through a heat scribing process or by adding adhesive between the carriage and the base. The heat scribing process may include applying heat to a projection (e.g., 222) extending from the carriage through a recess (e.g., 220) formed at the fixed end of the base.

[0050] In some cases, the support portion of the fixed end (e.g., 218) is removed by a removal process in order to disconnect the first set of electrical contacts at the fixed end. In some cases, the SMA actuator may include a carriage and a load point (e.g., 228 in Figure 2F) containing dielectric material. The load point may be injection molded to the free end.

[0051] In some cases, the SMA actuator may include a pair of reinforcing ribs (e.g., 226a-c in Figure 2E) positioned adjacent to a second set of electrical contacts at the free end. The pair of reinforcing ribs may be made of dielectric material. The pair of reinforcing ribs may be injection molded at the free end.

[0052] In some cases, the carriage and insulator comprise a single piece made of a dielectric material. For example, the carriage 304 and the insulator 316 may include a single piece made of a dielectric material.

[0053] In some cases, the SMA actuator may include a first joint element (e.g., 534a) injection-molded at the fixed end and a second joint element (e.g., 534b) injection-molded at the free end. The first and second joint elements may include a dielectric material that electrically insulates at least two SMA wires from the base. A beam (e.g., 512) may be connected to the fixed end via the first joint element and to the free end via the second joint element.

[0054] In some cases, the beam (e.g., 612) and insulator (e.g., 616) comprise a single piece made of dielectric material. In some cases, the SMA actuator may be part of a lens assembly as an autofocus actuator or part of an optical image stabilization system.

[0055] In another exemplary embodiment, a method for manufacturing a shape memory alloy (SMA) actuator is provided. The method may include engaging a carriage with a base. The base may include a fixed end fixed to the carriage, a free end, a beam connecting the fixed and free ends, and at least two SMA wires. Each of the at least two SMA wires may be electrically connected to the fixed end at a first set of electrical contacts and to the free end at a second set of electrical contacts. The at least two SMA wires may be configured to drive the free end of the base in response to receiving an electric current. The method may also include placing an insulator at the fixed end of the base via an injection molding process. The insulator comprises a dielectric material and electrically insulates the first set of electrical contacts at the fixed end of the base.

[0056] In some cases, engaging the carriage to the base involves either a heat scribing process that includes applying heat to a projection extending from the carriage through a recess formed in the fixed end of the base, or adding adhesive between the carriage and the base.

[0057] In some cases, the method involves removing the support portion of the fixed end by a removal process in order to disconnect the first set of electrical contacts of the fixed end. In some cases, the method involves positioning a load point containing dielectric material on the free end during the injection molding process.

[0058] In some cases, the carriage is made of a dielectric material and engages with the base during the injection molding process. In some cases, the method includes positioning a first bonding element made of a dielectric material at a fixed end via an injection molding process and positioning a second bonding element at a free end via an injection molding process. The first and second bonding elements can electrically insulate at least two SMA wires from the base. The beam may be connected at the fixed end via the first bonding element and at the free end via the second bonding element.

[0059] In some cases, the beams include dielectric material. The method may also include positioning the beams at fixed and free ends of the base via an injection molding process. In another exemplary embodiment, an SMA actuator is provided. The SMA actuator may include a carriage and a base. The base may include a fixed end fixed to the carriage, a free end, a beam connecting the fixed end and the free end, and at least two SMA wires. Each of the at least two SMA wires is electrically connected to the fixed end at a first set of electrical contacts and to the free end at a second set of electrical contacts. The at least two SMA wires may be positioned above the base, except for the first set of electrical contacts and the second set of electrical contacts, to electrically insulate the at least two SMA wires from the base.

[0060] In some cases, at least two SMA wires are coated. In some cases, the SMA actuator may include a first bumper positioned at the fixed end between at least two SMA wires and the fixed end of the base, and a second bumper positioned at the free end between at least two SMA wires and the free end of the base.

[0061] In some cases, the first set of electrical contacts is cast so that at least two SMA wires are offset from the base. It should be understood that terms such as “top,” “bottom,” “upward,” “downward,” and the x, y, and z directions, as used herein for convenience, refer to the spatial relationships of multiple parts relative to each other, and not to any particular spatial or gravitational orientation. Therefore, the terms shall include the assembly of parts of the components, regardless of whether the assembly is oriented in a particular orientation shown in the drawings and described herein, inverted from that orientation, or any other rotational variation.

[0062] It will be recognized that the term “invention” as used herein should not be construed to mean that only a single invention having a single essential element or group of elements is presented. Similarly, it will be recognized that the term “invention” may include several separate inventions, each of which may be considered a separate invention. Although the invention has been described in detail with respect to preferred embodiments and their drawings, it will be apparent to those skilled in the art that various adaptations and modifications of embodiments of the invention can be achieved without departing from the spirit and scope of the invention. Accordingly, it will be understood that the detailed description and accompanying drawings described above are not intended to limit the scope of the invention, and this should be inferred solely from the following claims and their appropriately interpreted legal equivalents.

Claims

1. Shape memory alloy (SMA) actuator, The carriage and, It's the base, A fixed end fixed to the carriage, The free end and A beam connecting the fixed end and the free end, At least one SMA wire electrically connected to the fixed end at a first set of electrical contacts and electrically connected to the free end at a second set of electrical contacts, wherein the at least one SMA wire is configured to drive the free end of the base in response to receiving an electric current, and A base that includes, An insulator comprising a dielectric material disposed at the fixed end of the base through an injection molding process, wherein the insulator electrically insulates the first set of electrical contacts at the fixed end of the base. An SMA actuator equipped with this feature.

2. The SMA actuator according to claim 1, wherein the carriage is engaged with the base by either a heat scrimping process or by adding an adhesive between the carriage and the base, the heat scrimping process comprising applying heat to a projection extending from the carriage through a recess formed in the fixed end of the base.

3. The SMA actuator according to claim 1, wherein the support portion of the fixed end is removed by a removal process in order to disconnect the first set of electrical contacts at the fixed end.

4. The SMA actuator described in claim 1 further, An SMA actuator comprising a load point containing the dielectric material, wherein the load point is injection-molded on the free end.

5. The SMA actuator described in claim 1 further, An SMA actuator comprising a pair of reinforcing ribs positioned adjacent to the second pair of electrical contacts at the free end, wherein the pair of reinforcing ribs comprises the dielectric material, and the pair of reinforcing ribs are injection molded onto the free end.

6. The SMA actuator according to claim 1, wherein the carriage and the insulator comprise a single piece made of a dielectric material.

7. The SMA actuator described in claim 1 further, A first joint element injection-molded at a fixed end, The second joining element, which is injection molded at the free end, An SMA actuator comprising, wherein the first and second bonding elements include a dielectric material that electrically insulates the at least one SMA wire from the base, and the beam is connected to the fixed end via the first bonding element and to the free end via the second bonding element.

8. The SMA actuator according to claim 1, wherein the beam and the insulator comprise a single piece made of the dielectric material.

9. The SMA actuator according to claim 1, wherein the SMA actuator is part of a lens assembly as an autofocus actuator or part of an optical image stabilization system.

10. A method for manufacturing a shape memory alloy (SMA) actuator, The carriage is engaged with the base, and the base is A fixed end fixed to the carriage, The free end and A beam connecting the fixed end and the free end, At least one SMA wire electrically connected to the fixed end at a first set of electrical contacts and electrically connected to the free end at a second set of electrical contacts, wherein the at least one SMA wire is configured to drive the free end of the base in response to receiving an electric current, and Including, The insulator is positioned at the fixed end of the base via an injection molding process. A method comprising, wherein the insulator comprises a dielectric material, and the insulator electrically insulates the first set of electrical contacts at the fixed end of the base.

11. A method according to claim 10, wherein the carriage is engaged with the base, A heat scribing process including applying heat to a projection extending from the carriage through a recess formed in the fixed end of the base, A method comprising either adding an adhesive between the carriage and the base.

12. The method according to claim 10 is, A method comprising removing the support portion of the fixed end through a removal process in order to disconnect the first set of electrical contacts at the fixed end.

13. The method according to claim 10 is, A method comprising positioning a load point containing the dielectric material on a free end during the injection molding process.

14. The method according to claim 10, wherein the carriage comprises the dielectric material, and the carriage engages with the base during the injection molding process.

15. The method according to claim 10 is, The injection molding process involves arranging a first bonding element made of the dielectric material at the fixed end, The second joining element is positioned at the free end through the injection molding process. A method comprising the first and second joining elements electrically insulating the at least one SMA wire from the base, wherein the beam is connected to the fixed end via the first joining element and to the free end via the second joining element.

16. A method according to claim 10, wherein the beam includes the dielectric material, and the method A method comprising positioning the beam at the fixed end and the free end of the base through the injection molding process.

17. Shape memory alloy (SMA) actuator, The carriage and, It's the base, A fixed end fixed to the carriage, The free end and A beam connecting the fixed end and the free end, At least one SMA wire electrically connected to the fixed end in a first set of electrical contacts and electrically connected to the free end in a second set of electrical contacts, wherein the at least one SMA wire is electrically insulated from the base by at least one SMA wire positioned above the base, except for the first set of electrical contacts and the second set of electrical contacts. Includes a base and An SMA actuator equipped with this feature.

18. The SMA actuator according to claim 17, wherein the at least one SMA wire is covered with a coating.

19. The SMA actuator described in claim 17 is further: A first bumper positioned at the fixed end between the at least one SMA wire and the fixed end of the base, A second bumper positioned at the free end between the at least one SMA wire and the free end of the base SMA actuators including

20. The SMA actuator according to claim 17, wherein the first set of electrical contacts is cast so as to offset the at least one SMA wire from the base.

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