Continuous wiring of shape memory alloy actuators

Abstract

Embodiments of the present technology provide methods for manufacturing a large number of shape memory alloy (SMA) actuator assemblies, which may also advantageously simplify and / or speed up the process of manufacturing the SMA actuator assemblies.

Description

[0001] The present application relates generally to techniques for manufacturing shape memory alloy (SMA) actuators, and more particularly to techniques for manufacturing large quantities of SMA actuators.

[0002] In a first method of the present technology, a method for manufacturing a shape memory alloy (SMA) subassembly is provided, comprising: providing a sheet of material, the sheet of material comprising a plurality of stationary wire attachment structures and a plurality of movable wire attachment structures; laying at least one SMA actuator wire on the stationary wire attachment structures and the movable wire attachment structures using a continuous wiring mechanism; attaching at least one SMA actuator wire to the stationary wire attachment structures and the movable wire attachment structures; and separating a plurality of SMA subassemblies from the sheet of material, each SMA subassembly comprising a sacrificial body portion integrally formed with at least one stationary wire attachment structure and at least one movable wire attachment structure.

[0003] In a second method of the present technology, a method for manufacturing a shape memory alloy (SMA) actuator is provided, comprising: providing a support structure; providing a movable component, wherein the movable component is supported on the support structure in a manner that allows the movable component to move relative to the support structure; providing an SMA subassembly manufactured using any of the (continuous wiring) methods described herein on the support structure and the movable component; attaching a stationary wire attachment structure and a movable wire attachment structure of the SMA subassembly to the support structure and the movable component, respectively; and separating the stationary wire attachment structure and the movable wire attachment structure from a sacrificial body portion of the SMA subassembly.

[0004] In a third method of the present technology, an array of shape memory alloy (SMA) sub-components is provided, comprising: a plurality of sacrificial body portions connected in a one-dimensional or two-dimensional array, each sacrificial body portion being integrally formed with at least one stationary wire attachment structure and at least one movable wire attachment structure; and at least one SMA actuator wire attached to the stationary wire attachment structure and the movable wire attachment structure, wherein the at least one SMA actuator wire is disposed on the stationary wire attachment structure and the movable wire attachment structure using a continuous wiring process.

[0005] In a fourth method of the present technology, a method for manufacturing a shape memory alloy (SMA) actuator is provided, comprising: providing a plurality of support structures; providing a movable component on each of the plurality of support structures, each movable component being supported on the support structure in a manner allowing the movable component to move relative to the support structure; providing an array of SMA subassemblies as described herein on the plurality of support structures and the movable components; attaching a stationary wire attachment structure and a movable wire attachment structure of each SMA subassembly to the support structure and the movable component, respectively; cutting at least one SMA actuator wire between adjacent SMA subassemblies; and separating the stationary wire attachment structure and the movable wire attachment structure from a sacrificial body portion of each SMA subassembly.

[0006] In a fifth method of the present technology, a shape memory alloy (SMA) actuation device manufactured using any of the continuous wiring and assembly methods described herein is provided.

[0007] In a sixth method of the present technology, a shape memory alloy (SMA) actuator device is provided, comprising: a stationary component, which includes four stationary wire attachment structures; a movable component, which is movable relative to the stationary component and includes two movable wire attachment structures; and at least two shape memory alloy (SMA) actuator wires, which are connected between the movable component and the stationary component and are arranged to move the movable component when contracted.

[0008] In a seventh method of the present technology, a device is provided that includes an SMA actuation device of the type described herein.

[0009] The device may be any of the following: a smartphone, a camera, a foldable smartphone, a foldable image capture device, a foldable smartphone camera, a foldable consumer electronic device, an image capture device, a 3D sensing device or system, a consumer electronic device, a mobile computing device, a mobile electronic device, a laptop computer, a tablet computing device, an e-reader (also known as an e-book reader or e-book device), a computing accessory or computing peripheral device (e.g., a mouse, a keyboard, a headset, earphones, earbuds, etc.), a security system, a medical device (e.g., an endoscope), a gaming system, a gaming accessory (e.g., a controller, a headset, a wearable controller, etc.), an augmented reality system, an augmented reality device, a virtual reality system, a virtual reality device, a haptic device, a medical device, a wearable device, a drone (aerial, aquatic, underwater, etc.), an autonomous vehicle, and a vehicle (e.g., an airplane, a spacecraft, a submersible, a car, etc.). It should be understood that this is a non-exhaustive list of example devices.

[0010] The SMA actuated devices described herein may be used in devices / systems suitable for, for example, image capture, 3D sensing, depth mapping, aerial surveying, terrestrial surveying, surveying in or from space, hydrographic surveying, underwater surveying, scene detection, collision warning, security, medical imaging, facial recognition, augmented and / or virtual reality, advanced driver assistance systems in vehicles, haptics, medical and surgical procedures, autonomous vehicles, gaming, gesture control / recognition, and robotic devices.

[0011] Preferred features are set out in the attached dependent claims.

[0012] Embodiments of the present technology will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0013] Figure 1 A shows a schematic cross-sectional view of a camera arrangement;

[0014] Figure 1 B shows the Figure 1 A top view of the arrangement of the SMA actuator wires along the optical axis of the camera device;

[0015] Figure 1 C shows Figure 1 A is a perspective view of the arrangement of SMA actuator wires in a camera device;

[0016] Figure 2 A shows a schematic diagram of a sequential wiring process for manufacturing an SMA subassembly of an SMA actuator;

[0017] Figure 2 B shows the Figure 2 A top view of an SMA subassembly produced by the continuous wiring process of A;

[0018] Figure 3 A shows a close-up of the removable wire attachment structure of the SMA subassembly;

[0019] Figure 3 B shows the Figure 2 A close-up of the tabs that guide the SMA actuator wires during the continuous wiring process;

[0020] Figure 4 Shown in Figure 2 A schematic diagram of a wire distribution header used in the continuous wiring process of A; and

[0021] Figure 5 A flow chart showing example steps performed in a continuous routing process.

[0022] In summary, embodiments of the present technology provide methods for manufacturing a large number of shape memory alloy (SMA) actuator assemblies, which may also advantageously simplify and / or speed up the process of manufacturing the SMA actuator assemblies.

[0023] In international patent publications WO2013 / 175197 and WO2014 / 083318 a shape memory alloy (SMA) actuator assembly is described for actuating movement of a movable element in two dimensions perpendicular to a main axis. Such actuators can be used for optical image stabilization (OIS) in miniature cameras. These actuators comprise four SMA wires connected between a movable element and a fixed support. Each wire is connected to the movable element at one of its ends (the moving crimp) with a crimp and to a support structure at its other end (the stationary crimp). Reference is now made to Figure 1 A to Figure 1 C describes the actuator in WO2013 / 175197 in more detail.

[0024] Figure 1 A shows a schematic cross-sectional view of a camera device 1, which is an example of an SMA actuation device and is cut along an optical axis O (which is an imaginary main axis). In order to clearly describe the main parts of the camera device 1, Figure 1 The SMA actuator wires are not shown in A, but are referred to later. Figure 1 B and Figure 1 C describes an SMA actuator line. The camera device 1 can be incorporated into a variety of devices, such as smartphones, foldable smartphones, foldable image capture devices, foldable smartphone cameras, foldable consumer electronic devices, image capture devices, 3D sensing devices or systems, consumer electronic devices, mobile computing devices, mobile electronic devices, laptop computers, tablet computing devices, e-readers (also known as e-book readers or e-book devices), computing accessories or computing peripherals, security systems, medical devices (such as endoscopes), gaming systems, gaming accessories, augmented reality systems, augmented reality devices, virtual reality systems, virtual reality devices, wearable devices, drones (air, water, underwater, etc.), autonomous vehicles, and vehicles (such as airplanes, spacecraft, submersibles, cars, etc.). It should be understood that this is a non-exhaustive list of example devices. In some cases, miniaturization is an important design criterion for the camera device 1.

[0025] The camera device 1 comprises a lens element 2 supported on a support structure 4 by a suspension system 7 in a manner allowing movement of the lens element 2 relative to the support structure 4 in two orthogonal directions, each being perpendicular to the optical axis O. The lens element 2 is therefore a movable element / component.

[0026] The support structure 4 is a camera support supporting an image sensor 6 on the front side of its base 5. On the rear side of the base 5 an IC (Integrated Circuit) chip 30 in which a control circuit 40 is implemented and also a gyro sensor 47 is mounted.

[0027] The lens element 2 comprises a lens holder 21 in the form of a cylindrical body which supports a lens 22 arranged along the optical axis O, but in general any number of lenses 22 may be provided. The camera device 1 is a miniature camera, wherein the diameter of the lens 22 (or each lens 22 if a plurality of lenses are provided) is less than or equal to 10 mm, or more preferably less than or equal to 20 mm.

[0028] The lens element 2 is arranged to focus the image onto an image sensor 6. The image sensor 6 captures the image and may be of any suitable type, for example a CCD (charge coupled device) or CMOS (complementary metal oxide semiconductor) device.

[0029] The lens 22 may be fixed relative to the lens holder 21, or alternatively may be supported on the lens holder in such a way that the lens 22 (or at least one lens 22 if multiple lenses are provided) can be moved along the optical axis O, for example in order to provide focusing. In the case where the lens 22 is movable along the optical axis O, a suitable actuation system (not shown) may be provided, for example using a voice coil motor or SMA actuator wire, such as described in International Patent Publication No. WO2007 / 113478.

[0030] In operation, the lens element 2 moves relative to the image sensor 6 in two orthogonal directions (shown as X and Y) orthogonal to the optical axis O, with the result that the image on the image sensor 6 is shifted. This serves to provide optical image stabilization (OIS), thereby compensating for image movement of the camera device 1 caused by, for example, hand shake.

[0031] In many known devices that use SMA actuator wires to provide OIS functionality, such as disclosed in International Patent Publications WO2010 / 029316 and WO2010 / 089529, OIS is provided by tilting the entire camera unit (essentially as a rigid body) including the lens element and image sensor. This method of compensating for user hand shake does in principle give the best OIS performance, because aligning the lens element with the image sensor in a miniature camera is difficult and the manufacturing tolerances are very tight. Furthermore, the user hand shake that is compensated is essentially a tilt of the camera, and it is therefore intuitive that the compensation should also tilt the camera. However, in this example, in order to alleviate several other problems, OIS is implemented in a different way.

[0032] The first problem is that with the "camera tilt" approach, the image sensor is moving relative to the fixed camera structure. This creates great difficulties in routing electrical connections from the image sensor to the fixed camera structure and to the mobile phone motherboard. Solutions for this mainly revolve around flexible printed circuits (FPCs) to route the connections, but FPC design remains challenging due to the large number of connections and high data rates. Therefore, it is highly desirable for the image sensor to remain stationary and fixed.

[0033] The second problem is that the camera tilting approach means that there is a camera structure including at least the lens and the image sensor, whose support structure must be tilted within the surrounding support structure. Because the camera has a limited footprint, the tilting of the camera means that the camera thickness (height) of the OIS camera must be greater than the equivalent camera without OIS. In mobile phones, minimizing the camera height is a pressing need.

[0034] A third problem is that, since the entire camera is tilted, it is difficult to package the tilt actuator without increasing the packaging space of the camera compared to a camera without OIS.

[0035] Therefore, in Figure 1 In A, the lens element 2 is linearly moved in two orthogonal directions, both perpendicular to the optical axis O, which may be referred to as "shift" or "OIS-shift". The resulting image compensation does not completely reverse the effects of user hand shake, but the performance is considered to be sufficiently good considering the above-mentioned limitations and allows the size of the camera device 1 to be reduced, in particular compared to devices using tilt.

[0036] Figure 1 B shows the Figure 1A top view of an arrangement of SMA actuator wires along the optical axis of the camera arrangement in FIG. Each of the SMA actuator wires 11 to 14 is arranged along one side of the lens element 2. Thus, the SMA actuator wires 11 to 14 are arranged in a loop at different angular positions around the optical axis O. Thus, the four SMA actuator wires 11 to 14 consist of a first pair of SMA actuator wires 11 and 13 arranged on opposite sides of the optical axis O and a second pair of SMA actuator wires 12 and 14 arranged on opposite sides of the optical axis O. The first pair of SMA actuator wires 11 and 13 are capable of moving the lens element 2 relative to the support structure 4 in a first direction within the plane upon selective actuation, while the second pair of SMA actuator wires 12 and 14 are capable of moving the lens element 2 relative to the support structure 4 in a second direction transverse to the first direction within the plane upon selective actuation. Movement in directions other than parallel to the SMA actuator wires 11 to 14 can be driven by a combination of actuations of pairs of these SMA actuator wires 11 to 14 to provide a linear combination of movement in the lateral direction. Another way to view this movement is that simultaneous contraction of any pair of SMA actuator wires 11 to 14 that are adjacent to each other in the loop will drive the lens element 2 to move in a direction that bisects the two SMA actuator wires 11 to 14 (in a direction that is parallel to the SMA actuator wires 11 to 14). Figure 1 B, as indicated by arrows X and Y).

[0037] Thus, the SMA actuator wires 11 to 14 can be selectively driven to move the lens element 2 relative to the support structure 4 to any position within a range of movement in two orthogonal directions perpendicular to the optical axis O. The size of the range of movement depends on the geometry and the range of contraction of the SMA actuator wires 11 to 14 within their normal operating parameters.

[0038] Figure 1 C shows Figure 1 A perspective view of an arrangement of SMA actuator wires in a camera arrangement of FIG. Actuator arrangement 10 comprises a total of four SMA actuator wires 11 to 14 connected between a support block 16 forming part of a support structure 4 and mounted to a base 5 and a movable platform 15 forming part of a lens element 2 and mounted to a base 5. Figure 1 A shows the rear part of the lens plate 73.

[0039] Each of the SMA actuator wires 11 to 14 is held in tension, thereby exerting a force between the movable platform 15 and the support block 16 in a direction perpendicular to the optical axis O. In operation, the SMA actuator wires 11 to 14 move the lens element 2 relative to the support block 16 in two orthogonal directions perpendicular to the optical axis O.

[0040] The SMA actuator wires 11 to 14 are connected to the movable platform 15 at one end by respective crimping members 17 and to the support block 16 at the other end by crimping members 18. The crimping members 17 and 18 crimp the wires to mechanically hold the wires, optionally reinforced by the use of an adhesive. The crimping members 17 and 18 also provide electrical connections to the SMA actuator wires 11 to 14. However, any other suitable means for connecting the SMA actuator wires 11 to 14 may alternatively be used.

[0041] This technology is Figure 1 A to Figure 1 C provides improvements in the manufacture / assembly of actuators and camera modules of the type shown in FIG. The technology described herein can be used to manufacture any type of SMA actuator, including the four-wire actuator described above and the eight-wire actuator of the type described in International Patent Publication No. WO2011 / 104518. It should be understood that the technology described herein can be used to manufacture SMA actuators or actuating devices for any device / system, which is suitable for, for example, image capture, 3D sensing, depth mapping, aerial surveying, land surveying, measurement in space or from space, hydrographic surveying, underwater surveying, scene detection, collision warning, security, medical imaging, medical / surgical procedures, facial recognition, augmented and / or virtual reality, advanced driver assistance systems in vehicles, autonomous vehicles, gaming, gesture control / recognition, tactile and robotic devices. Therefore, the technology is not limited to manufacturing SMA actuators for cameras, but can be more widely used to manufacture SMA actuators for any technology.

[0042] Figure 2 A shows a schematic diagram of a continuous wiring process 100 for manufacturing an SMA subassembly 102 for an SMA actuator. Figure 2 A shows one particular type of SMA subassembly 102, and it will be appreciated that the design of the subassembly may vary depending on the SMA actuator being manufactured. For example, an SMA actuator for delivering tactile feedback may include an SMA actuator wire held between / by two crimps (a moving crimp and a stationary crimp). In this case, the individual SMA subassemblies may be very simple. Thus, Figure 2 A to Figure 4 The SMA subassembly shown is merely one illustrative and non-limiting version of a subassembly, and those skilled in the art will appreciate that the specific features and layout of the subassembly may vary for a variety of reasons, including different technologies and different actuator designs.

[0043] The SMA actuator includes a stationary component and a movable component, the stationary component includes four stationary wire attachment structures (e.g., crimping parts), and the movable component is movable relative to the stationary component. The movable component also includes two movable wire attachment structures (e.g., crimping parts). The SMA actuator may include at least two shape memory alloy (SMA) actuator wires connected between the movable component and the stationary component. The SMA actuator wire is arranged to move the movable component when it is contracted. The precise movement and control of the movable component may depend on the accuracy of the SMA actuator wires relative to each other, and therefore on the precise position of the wire attachment structure on the stationary component and the movable component. Typically, the stationary component and the movable component of the SMA actuator and the wire attachment structure are assembled before the SMA actuator wire is attached to the SMA actuator. However, this is a difficult process because SMA actuators are typically very small, such as 6.5 mm×6.5 mm up to 12 mm×12 mm. In addition, the length of the SMA actuator wire attached to the wire attachment structure (e.g., held by the crimping part) may need to be precisely controlled. If one SMA actuator wire is taut and the other SMA actuator wire is slack, it may be difficult to control the movement of the movable component.

[0044] Therefore, a problem that arises when manufacturing SMA actuator assemblies is how to increase the throughput of the wiring process. One solution may include utilizing a continuous wiring process, which may require having some of the following: a single common crimp at each corner, formed tabs for wire routing and length control, SMA wire, and a wire distribution header.

[0045] These problems can be solved by "off board" crimping, i.e., by attaching the SMA actuator wires to the wire attachment structures outside the SMA actuator and then assembling the SMA actuator. This simplifies the SMA actuator wiring process. In addition, if the wire attachment structures are provided on a sheet or strip of material, long lengths of SMA actuator wires can be attached to a large number of wire attachment structures. This can advantageously increase manufacturing speed and productivity. The SMA subassemblies can be cut from the sheet / strip of material as needed and used to assemble the SMA actuator.

[0046] Figure 2A shows a portion of a sheet / strip of material 108 for performing "off-site" wiring and crimping. The sheet / strip of material 108 may include a plurality of movable wire attachment structures 104a and a plurality of stationary wire attachment structures 104b. The movable wire attachment structures 104a and the stationary wire attachment structures 104b may be crimping portions. The movable wire attachment structures 104a and the stationary wire attachment structures 104b may be formed in the sheet of material 108 by forming the material 108 into a desired shape. The sheet of material 108 may be formed of any material that enables the wire attachment structures 104a, 104b to form a good electrical and mechanical connection with the SMA actuator wires. For example, the sheet of material 108 may be formed of phosphor bronze or stainless steel.

[0047] The wire attachment structures (or crimps) 104a, 104b may be arranged on the material sheet 108 so that after the wiring process has been completed, the SMA subassemblies 102 may be easily cut or separated from the material sheet 108. Each SMA subassembly 102 may include four stationary wire attachment structures 104b and two movable wire attachment structures 104a. Figure 2 A shows one complete SMA subassembly 102 and a portion of another subassembly. Two movable wire attachment structures 104a may be held in a fixed position relative to each other by being part of a divider 107. Four stationary wire attachment structures 104b may be formed in a sheet of material 108 in fixed positions relative to each other and relative to the movable wire attachment structures 104a.

[0048] The material sheet 108 may also include one or more lugs or path control elements 106. The lugs / path control elements 106 may be used to control the position and length of the SMA actuator wires set between the line attachment structures 104a, 104b. A wire dispensing head 112 or similar device / tool ​​may be used to dispense the SMA actuator wires from a spool or reel (not shown). In an embodiment, the wire dispensing head 112 may be maintained in a fixed position, while the material sheet 108 may be moved relative to the wire dispensing head 112. Thus, when the material sheet 108 moves past the wire dispensing head 112, the wire dispensing head 112 may dispense / lay the SMA actuator wires 110 on the line attachment structures 104a, 104b. Alternatively, the material sheet 108 may be maintained in a fixed position, while the wire dispensing head 112 may be moved on the material sheet 108. Optionally, both the wire dispensing head 112 and the sheet of material 108 may be movable to enable the SMA actuator wires 110 to be laid onto the wire attachment structures 104a, 104b.

[0049] In an embodiment, the wire dispensing head 112 may be used to lay one SMA actuator wire 110 on half of the wire attachment structures 104a, 104b, such as Figure 2A. Another wire dispensing head 112 or the same wire dispensing head 112 can be used to lay another SMA actuator wire 110 on the other half of the wire attachment structures 104a, 104b. Thus, two SMA actuator wires 110 can be laid on the wire attachment structures 104a, 104b in a cross or staggered manner. Alternatively, the wire dispensing head 112 can be used to lay one SMA actuator wire 110 on all of the wire attachment structures 104a, 104b of one SMA subassembly 102 before moving to the next subassembly. However, this may not be as efficient as following a cross pattern.

[0050] like Figure 2 As shown in FIG. 1A , when the wire dispensing head 112 lays the SMA actuator wire 110, it can be arranged around the tab / path control element 106. The tab 106 can be arranged in the material sheet 108 by shaping the material sheet. The guide tab 106 protrudes from the material sheet 108 and is arranged between adjacent wire attachment structures 104a, 104b, and the wire direction guide tab 114 is arranged between the wire attachment structures of adjacent sub-assemblies. Figure 2 In FIG. 1A , three guide tabs 106 are disposed between adjacent wire attachment structures, while four wire direction guide tabs 114 are disposed between adjacent subassemblies 102 . However, it should be understood that any number of guide tabs 106 may be disposed to control the position and length of the SMA actuator wire 110 between the wire attachment structures 104 a, 104 b. The wire direction guide tabs 114 disposed between adjacent subassemblies 102 may be used to control the angle of the SMA actuator wire 110 as it leaves one subassembly and approaches another subassembly so that the SMA actuator wire 110 is not excessively twisted or bent. Figure 2 As shown in FIG. 1A , the SMA actuator wires 110 may be interwoven between the guide tabs 106. A greater number of tabs 106 may increase the amount of SMA actuator wires 110 between the various wire attachment structures 104a, 104b. This may be useful if the SMA actuator wires 110 are required to be slack (i.e., have zero tension) when the wires are not energized.

[0051] Figure 2 B shows the Figure 21. A top view of an SMA subassembly 102 produced by a continuous wiring process of FIG. 1. After the wiring process is completed, the subassembly 102 has been cut / separated from the sheet of material 108. When it is necessary to assemble the SMA actuator, the subassembly 102 can be separated from the sheet of material 108. The wire attachment structures 104a, 104b can be attached to the movable and stationary components of the SMA actuator by any suitable process, such as welding or laser welding. The movable wire attachment structure 104a can be separated from the separator 107 after the welding process to the movable component, so that the movable wire attachment structures 104a remain separated from each other by a desired distance during the welding process.

[0052] Therefore, an embodiment of the present technology can provide a shape memory alloy (SMA) actuation device, comprising: a stationary component, which includes four stationary wire attachment structures 104b; a movable component, which is movable relative to the stationary component and includes two movable wire attachment structures 104a; and at least two shape memory alloy (SMA) actuator wires 110, which are connected between the movable component and the stationary component and are arranged to move the movable component when contracted.

[0053] The SMA actuation device may include a total of two SMA actuator wires connected between a movable component and a stationary component and arranged to move the movable component when contracted, wherein each SMA actuator wire: is coupled to one of four stationary wire attachment structures at a first end, is coupled to another of the four stationary wire attachment structures at a second end; and is coupled to one of the movable wire attachment structures part-way along its length.

[0054] The SMA actuation device may include a total of four SMA actuator wires connected between a movable component and a stationary component and arranged to move the movable component when contracted, wherein each SMA actuator wire: is coupled to one of the four stationary wire attachment structures at a first end, and is coupled to one of the movable wire attachment structures at a second end, such that each movable wire attachment structure is coupled to two SMA actuator wires.

[0055] The movable component may be movable relative to the stationary component in two orthogonal directions perpendicular to an imaginary principal axis extending through the movable component.Thus, in embodiments where the movable component is an optical component, the SMA actuation arrangement may be able to provide optical image stabilization (OIS).

[0056] In an embodiment, the SMA actuator wire of the SMA actuation device may be slack.

[0057] The SMA actuation device may be formed using a continuous wiring process.

[0058] One problem that may arise when performing a continuous wiring process is how to hold the SMA actuator wire in the movable crimp 104a so that a good electrical and mechanical connection is made when the crimp is closed. Therefore, it is necessary to hold the wire in the movable crimp 104a in preparation for crimping. One solution may be to use a single crimp (i.e., the movable crimp 104a) for the OIS common corner connection. The wire is fed onto two formed up guides on either side of the single crimp to hold it in place. Figure 3 A shows a close-up of the movable wire attachment structure 104a of the SMA subassembly 102. Two crimp guide tabs 116 are provided on both sides of the movable wire attachment structure 104a, and the SMA actuator wire 110 is threaded around the crimp guide tabs 116 before and during the crimping process to maintain the wire in a desired position in the crimping portion 104a. A first crimp guide tab 116 may be provided on a first side of each wire attachment structure, and a second crimp guide tab 116 may be provided on a second side of each wire attachment structure.

[0059] Another problem that may arise when utilizing a continuous wiring process is that the length of the SMA actuator wire between the various wire attachment structures 104a, 104b may be difficult to control. As described above, it is desirable to ensure that the length of the SMA actuator wire in each subassembly 102 is precisely controlled. In an embodiment, the length of the SMA actuator wire between adjacent crimps 104a, 104b may need to be exactly the same or within a certain tolerance allowed. However, if a wire dispensing head 112 is used to lay the SMA actuator wire 110 on the sheet of material 108, the length may not be well controlled. Therefore, problems may arise in controlling the length and position of the wire during the continuous wiring process. One solution may be to use a formed guide lug 106 for wire path and length control. Figure 3 B shows the Figure 2 1. A close-up of the guide tabs 106 that guide the SMA actuator wires during the continuous routing process of FIG. A. The SMA actuator wires 110 are threaded or interwoven between the tabs 106, and the technique is able to control both the position of the SMA actuator wires 110 relative to the crimps 104a, 104b and the amount of wire 110 between adjacent crimps. The tabs 106 ensure that a fixed amount of SMA actuator wires 110 are placed along each length / side of the subassembly 102.

[0060] One problem that may arise is that of a suitable dispensing head capable of feeding wire around small features during continuous routing. One solution may be to use a wire dispensing head 110 in the form of a capillary or small roller. Figure 4 Shown in Figure 2A schematic diagram of the wire dispensing head 110 used in the continuous routing process of FIG. 1 and how the wire dispensing head 110 needs to be moved around small features.

[0061] Figure 5 A flow chart showing example steps performed in a continuous wiring process is shown. The process begins by providing a sheet of material including a plurality of stationary wire attachment structures and a plurality of movable wire attachment structures (step S200). The process next uses a continuous wiring mechanism to lay at least one SMA actuator wire on the stationary wire attachment structures and the movable wire attachment structures (step S202). Then, at least one SMA actuator wire is attached to the stationary wire attachment structures and the movable wire attachment structures (step S204). After the wire laying and attachment (crimping) steps are completed, when it is necessary to assemble the SMA actuator, one or more SMA subassemblies can be separated from the sheet of material (step S206). Each SMA subassembly includes a sacrificial body portion integrally formed with at least one stationary wire attachment structure and at least one movable wire attachment structure.

[0062] The step of laying at least one SMA actuator wire may include laying an SMA actuator wire on the stationary wire attachment structure and the movable wire attachment structure such that each SMA subassembly includes an SMA actuator wire that is coupled to the stationary wire attachment structure at a first end and to the movable wire attachment structure at a second end.

[0063] The step of laying at least one SMA actuator wire may include laying an SMA actuator wire on the stationary wire attachment structure and the movable wire attachment structure such that each SMA subassembly includes an SMA actuator wire that is connected to the first stationary wire attachment structure at a first end, connected to the second stationary wire attachment structure at a second end, and connected to the movable wire attachment structure midway along its length.

[0064] The step of laying at least one SMA actuator wire may include laying two SMA actuator wires on a stationary wire attachment structure and a movable wire attachment structure such that each SMA subassembly includes two SMA actuator wires, each SMA actuator wire being connected to the stationary wire attachment structure at a first end and to the movable wire attachment structure at a second end.

[0065] The step of laying at least one SMA actuator wire may include: laying a total of two SMA actuator wires on the stationary wire attachment structure and the movable wire attachment structure, so that each SMA subassembly includes two SMA actuator wires, each SMA actuator wire: connected to a first stationary wire attachment structure at a first end, connected to a second stationary wire attachment structure at a second end; and connected to the movable wire attachment structure midway along its length.

[0066] The step of laying at least one SMA actuator wire may include laying a total of four SMA actuator wires on the stationary wire attachment structure and the movable wire attachment structure, so that each SMA subassembly includes four SMA actuator wires, each SMA actuator wire: connected to one of the four stationary wire attachment structures at a first end, and connected to one of the two movable wire attachment structures at a second end, so that each movable wire attachment structure is connected to two SMA actuator wires.

[0067] The step of laying at least one SMA actuator wire may include laying a total of four SMA actuator wires on the stationary wire attachment structure and the movable wire attachment structure, so that each SMA subassembly includes four SMA actuator wires, each SMA actuator wire: connected to one of the four stationary wire attachment structures at a first end and connected to one of the four movable wire attachment structures at a second end.

[0068] The step of providing a sheet of material may include providing a sheet of phosphor bronze, steel or stainless steel material.

[0069] The step of providing a sheet of material may comprise providing a sheet of etched material which has been shaped to provide a plurality of stationary wire attachment structures and a plurality of movable wire attachment structures.

[0070] In an embodiment, the plurality of stationary attachment structures and the plurality of movable wire attachment structures may be open crimps, and the step of laying at least two SMA actuator wires on the stationary wire attachment structures and the movable wire attachment structures may include: laying at least one SMA actuator wire on the stationary open crimp and the movable open crimp. In this case, the step of attaching at least one SMA actuator wire to the stationary wire attachment structures and the movable wire attachment structures may include: closing the stationary open crimp and the movable open crimp around the at least one SMA actuator wire; and applying a punch tool to each of the closed stationary crimp and the closed movable crimp.

[0071] The step of separating the plurality of SMA subassemblies may include applying a punching tool to separate the body portion from the sheet of material. Alternatively, the step of separating the plurality of SMA subassemblies may include etching the sheet of material to separate the body portion from the sheet of material. Alternatively, the step of separating the plurality of SMA subassemblies may include cutting the sheet of material to separate the body portion from the sheet of material.

[0072] The step of separating the plurality of SMA subassemblies may include cutting at least one SMA actuator wire at a location on the sheet of material between adjacent SMA subassemblies. The cutting may be performed using a laser or a mechanical cutting process.

[0073] The step of laying the at least one SMA actuator wire may include weaving the at least one SMA actuator wire around one or more guide tabs in the sheet of material.

[0074] The step of laying at least one SMA actuator wire may include: laying at least one SMA actuator wire on a first wire attachment structure; weaving at least one SMA actuator wire between one or more guide ears on a sheet of material to control the position and length of the SMA actuator wire between adjacent wire attachment structures; and laying at least one SMA actuator wire on a second wire attachment structure.

[0075] The step of laying at least one SMA actuator wire may include laying the at least one SMA actuator wire on the wire attachment structure around one or more crimp guide tabs on the sheet of material near each wire attachment structure to hold the SMA actuator wire on the wire attachment structure. A first crimp guide tab may be disposed on a first side of the wire attachment structure, and a second crimp guide tab may be disposed on a second side of the wire attachment structure.

[0076] The step of laying out the at least one SMA actuator wire may include weaving the at least one SMA actuator wire around one or more wire direction guide tabs on the sheet of material to control the angle of the SMA actuator wire between adjacent SMA subassemblies.

[0077] The present technology can provide a method for manufacturing a shape memory alloy (SMA) actuator, comprising: providing a support structure; providing a movable component, which is supported on the support structure in a manner that allows the movable component to move relative to the support structure; providing an SMA subassembly manufactured using the above method on the support structure and the movable component; attaching a stationary wire attachment structure and a movable wire attachment structure of the SMA subassembly to the support structure and the movable component, respectively; and separating the stationary wire attachment structure and the movable wire attachment structure from a sacrificial body portion of the SMA subassembly.

[0078] The present technology may provide an array of shape memory alloy (SMA) subassemblies, comprising: a plurality of sacrificial body portions connected in a one-dimensional or two-dimensional array, each sacrificial body portion being integrally formed with at least one stationary wire attachment structure and at least one movable wire attachment structure; and at least one SMA actuator wire attached to the stationary wire attachment structure and the movable wire attachment structure, wherein the at least one SMA actuator wire is disposed on the stationary wire attachment structure and the movable wire attachment structure using a continuous wiring process.

[0079] The array of SMA subassemblies may also include a plurality of guide tabs for controlling the position and length of the SMA actuator wires between the wire attachment structures.

[0080] The array of SMA subassemblies may also include at least one crimp guide tab adjacent each wire attachment structure to hold the SMA actuator wire on the wire attachment structure during assembly. A first crimp guide tab may be disposed on a first side of each wire attachment structure, and a second crimp guide tab may be disposed on a second side of each wire attachment structure.

[0081] The array of SMA subassemblies may also include a plurality of wire direction guide tabs to control the angle of the SMA actuator wires between adjacent sacrificial body portions.

[0082] Other embodiments of the present technology are listed in the following numbered clauses:

[0083] 1. An SMA four-wire actuator, comprising four stationary crimping parts and two moving crimping parts.

[0084] 2. The SMA four-wire actuator of clause 1, wherein each moving crimp is connected to two SMA wires.

[0085] 3. An SMA actuator comprising two SMA wires, each wire being connected to a stationary crimp at its two ends and to a moving crimp at its center.

[0086] 4. An SMA actuator comprising two SMA wires, four stationary crimping parts and two moving crimping parts.

[0087] 5. An SMA actuator according to clause 3 or 4 driven to provide two-dimensional movement.

[0088] 6. An SMA actuator assembly process including continuous wiring.

[0089] 7. The SMA actuator assembly process of clause 6, wherein the SMA actuator includes shaped tabs to control the path and length of the wire.

[0090] 8. An SMA actuator assembly process according to clause 6, wherein a wire dispensing header is used.

[0091] 9. An SMA actuator assembly process according to clause 8, wherein the dispensing head is capable of feeding the line around small features.

[0092] 10. The SMA actuator assembly process of clause 8, wherein the dispensing head comprises a capillary tube or a roller.

[0093] 11. An SMA actuator assembly process according to clauses 6-10 for producing a 4-wire actuator.

[0094] 12. An SMA actuator assembly process according to clause 10, for producing an actuator according to clause 1 or 2.

[0095] 13. An SMA actuator assembly process according to clauses 7-9, for producing an actuator according to clauses 3-5.

[0096] Those skilled in the art will appreciate that, although the foregoing contents that are considered to be the best mode and other modes of carrying out the present technology where appropriate have been described, the present technology should not be limited to the specific constructions and methods of the preferred embodiments disclosed in this specification. Those skilled in the art will appreciate that the present technology has a wide range of applications and that the embodiments may be modified in a wide range without departing from any inventive concept defined by the appended claims.

Claims

1. A method for manufacturing a shape memory alloy (SMA) subassembly, comprising: providing a sheet of material including a plurality of stationary wire attachment structures and a plurality of movable wire attachment structures; Laying at least one SMA actuator wire on the stationary wire attachment structure and the movable wire attachment structure using a continuous routing mechanism, wherein the step of laying the at least one SMA actuator wire comprises: laying one SMA actuator wire on the plurality of stationary wire attachment structures and the plurality of movable wire attachment structures using a continuous routing mechanism; attaching the at least one SMA actuator wire to the stationary wire attachment structure and the movable wire attachment structure; and A plurality of SMA subassemblies are separated from the sheet of material, each SMA subassembly including a sacrificial body portion integrally formed with at least one stationary wire attachment structure and at least one movable wire attachment structure.

2. The method according to claim 1, wherein: The step of laying the at least one SMA actuator wire comprises: Laying an SMA actuator wire on the stationary wire attachment structure and the movable wire attachment structure such that each SMA subassembly includes an SMA actuator wire that: is coupled at a first end to a stationary line attachment structure, and Coupled to the movable wire attachment structure at the second end.

3. The method according to claim 1, wherein: The step of laying the at least one SMA actuator wire comprises: Laying an SMA actuator wire on the stationary wire attachment structure and the movable wire attachment structure such that each SMA subassembly includes an SMA actuator wire that: coupled at a first end to a first stationary line attachment structure, is coupled at a second end to a second stationary line attachment structure, and Connected to a removable wire attachment structure midway along its length.

4. The method according to claim 1, wherein: The step of laying the at least one SMA actuator wire comprises: Two SMA actuator wires are laid on the stationary wire attachment structure and the movable wire attachment structure such that each SMA subassembly includes two SMA actuator wires, wherein each SMA actuator wire: is coupled at a first end to a stationary line attachment structure, and Coupled to the movable wire attachment structure at the second end.

5. The method according to claim 1, wherein: The step of laying the at least one SMA actuator wire comprises: A total of two SMA actuator wires are laid on the stationary wire attachment structure and the movable wire attachment structure such that each SMA subassembly includes two SMA actuator wires, wherein each SMA actuator wire: coupled at a first end to a first stationary line attachment structure, coupled at a second end to a second stationary line attachment structure; and Connected to a removable wire attachment structure midway along its length.

6. The method according to claim 1, wherein: The steps of laying at least one SMA actuator wire include: A total of four SMA actuator wires are laid on the stationary wire attachment structure and the movable wire attachment structure such that each SMA subassembly includes four SMA actuator wires, wherein each SMA actuator wire: is coupled at a first end to one of the four stationary line attachment structures, and Coupled at the second end to one of the two movable wire attachment structures such that each movable wire attachment structure is coupled to two SMA actuator wires.

7. The method according to claim 1, wherein: The steps of laying at least one SMA actuator wire include: A total of four SMA actuator wires are laid on the stationary wire attachment structure and the movable wire attachment structure such that each SMA subassembly includes four SMA actuator wires, wherein each SMA actuator wire: is coupled at a first end to one of the four stationary line attachment structures, and Coupled at the second end to one of the four movable wire attachment structures.

8. A method according to any one of the preceding claims, wherein: The step of providing a sheet of material includes providing a sheet of phosphor bronze, steel or stainless steel material.

9. The method according to any one of claims 1 to 7, wherein: The step of providing a sheet of material comprises providing a sheet of etched material which has been shaped to provide the plurality of stationary wire attachment structures and the plurality of movable wire attachment structures.

10. The method according to any one of claims 1 to 7, wherein: The plurality of stationary wire attachment structures and the plurality of movable wire attachment structures are stationary open crimps and movable open crimps, respectively, and the step of laying the at least one SMA actuator wire on the stationary wire attachment structures and the movable wire attachment structures comprises: The at least one SMA actuator wire is laid over the stationary opening crimp and the movable opening crimp.

11. The method according to claim 10, wherein: The step of attaching the at least one SMA actuator wire to the stationary wire attachment structure and the movable wire attachment structure comprises: closing the stationary opening crimp and the movable opening crimp around the at least one SMA actuator wire; and A punching tool is applied to each of the closed stationary crimping part and the closed movable crimping part.

12. The method according to any one of claims 1 to 7, wherein: The step of separating the plurality of SMA subassemblies includes applying a punch tool to separate the sacrificial body portion from the sheet of material.

13. The method according to any one of claims 1 to 7, wherein: The step of separating the plurality of SMA subassemblies comprises: The sheet of material is etched to separate the sacrificial body portion from the sheet of material.

14. The method according to any one of claims 1 to 7, wherein: The step of separating the plurality of SMA subassemblies comprises: The sheet of material is cut to separate the sacrificial body portion from the sheet of material.

15. The method according to any one of claims 1 to 7, wherein: The step of separating the plurality of SMA subassemblies comprises: The at least one SMA actuator wire is cut on the sheet of material at a location between adjacent SMA subassemblies.

16. The method according to any one of claims 1 to 7, wherein: The step of laying out the at least one SMA actuator wire includes weaving the at least one SMA actuator wire around one or more guide tabs in the sheet.

17. The method according to any one of claims 1 to 7, wherein: The step of laying the at least one SMA actuator wire comprises: laying the at least one SMA actuator wire on a first wire attachment structure of the plurality of stationary wire attachment structures and the plurality of movable wire attachment structures; weaving the at least one SMA actuator wire between one or more guide tabs on the sheet of material to control the position and length of the SMA actuator wire between adjacent wire attachment structures; and The at least one SMA actuator wire is routed on a second wire attachment structure of the plurality of stationary wire attachment structures and the plurality of movable wire attachment structures.

18. The method according to any one of claims 1 to 7, wherein: The step of laying the at least one SMA actuator wire comprises: The at least one SMA actuator wire is laid on the wire attachment structure around one or more crimp guide tabs on the sheet of material in the vicinity of each wire attachment structure to retain the SMA actuator wire on the wire attachment structure.

19. The method according to claim 18, wherein: A first crimp guide tab is disposed on a first side of the wire attachment structure, and a second crimp guide tab is disposed on a second side of the wire attachment structure.

20. The method according to any one of claims 1 to 7, wherein: The step of laying the at least one SMA actuator wire comprises: The at least one SMA actuator wire is interwoven around one or more wire direction guide tabs on the sheet of material to control the angle of the SMA actuator wire between adjacent SMA subassemblies.

21. A method for manufacturing a shape memory alloy (SMA) actuator, comprising: Provide support structures; providing a movable member supported on the support structure in a manner allowing the movable member to move relative to the support structure; providing an SMA subassembly manufactured by the method of any one of claims 1 to 20 on the support structure and the movable component; attaching the stationary wire attachment structure and the movable wire attachment structure of the SMA subassembly to the support structure and the movable member, respectively; as well as The stationary wire attachment structure and the movable wire attachment structure are separated from the sacrificial body portion of the SMA subassembly.

Images