Memory alloy controller

Abstract

The invention belongs to the technical field of automobile valve control, and particularly relates to a memory alloy controller to relieve the problem of poor heat dissipation of a position where a shape memory alloy wire is connected with a valve rod in a hanging mode, the memory alloy controller comprises at least one control unit, and the control unit comprises a power supply module, the shape memory alloy wire and a conductive part. The shape memory alloy wire is electrically connected with the power supply module and connected with the valve, the shape memory alloy wire is divided into a first branch section and a second branch section at the position of the valve, and the conductive part is located between the first branch section and the second branch section; current flows through the whole first branch section and the whole second branch section in sequence from the power supply module and then flows back to the power supply module to form a first current loop; the current sequentially flows through part of the first branch section, the conductive part and part of the second branch section from the power supply module and then flows back to the power supply module to form a second current loop. The problems of local stress concentration and fatigue fracture caused by uneven heat dissipation of the alloy wire in a traditional structure are effectively solved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of automobile valve control, and particularly relates to a memory alloy controller. BACKGROUND

[0002] In the application of valves, micro actuators and the like, an SMA wire is usually connected with a load (such as a valve rod) through a mechanical hanging point (such as a hook or a clamping piece). When the SMA wire is heated and shrinks by being electrified, the Joule heat generated thereby is not only used for driving, but also conducted to a support structure through the hanging point. In the existing structure, the hanging point is usually made of plastic material, which leads to the accumulation of a large amount of heat. An excessively high temperature can affect the contraction accuracy and service life of the memory alloy wire, and easily causes the fracture of the memory alloy wire at the hanging point. The SMA segment near the hanging point is higher in temperature than the middle segment due to slow heat dissipation, which leads to the asynchronous contraction of the whole SMA wire and affects the movement accuracy and service life. The stress concentration caused by cold and heat alternation near the hanging point easily causes the fatigue fracture of the SMA wire at the hanging point. SUMMARY

[0003] In order to solve the heat dissipation problem in the prior art, the application provides a memory alloy controller.

[0004] In order to solve the above technical problem, the technical scheme provided by the application is as follows: A memory alloy controller comprises at least one control unit, and the control unit comprises: a power supply module; a shape memory alloy wire, which is electrically connected with the power supply module and connected with a valve, the shape memory alloy wire is divided into a first branch segment and a second branch segment at the valve, the valve has an open state and a closed state, and the length of the shape memory alloy wire changes after being electrified and heated to drive the valve to switch the open and closed states; a conductive part located between the first branch segment and the second branch segment; current flows from the power supply module to the whole first branch segment, the whole second branch segment and then back to the power supply module to form a first current loop; current flows from the power supply module to part of the first branch segment, the conductive part, part of the second branch segment and then back to the power supply module to form a second current loop.

[0005] Further, the conductive part comprises: an insulating fixed part arranged inside the conductive part; a conductive layer arranged outside the insulating fixed part, and current passes through the first branch segment, the conductive layer and then the second branch segment.

[0006] Further, the conductive part is made of metal, and is used to form a second current loop.

[0007] Further, the shape memory alloy wire is in contact with and electrically connected to the conductive part in the powered and unpowered states. Further, the shape memory alloy wire is not in contact with the conductive part in the unpowered state.

[0008] Further, an elastic insulating layer is arranged between the shape memory alloy wire and the conductive part. In the first stage, the elastic insulating layer isolates the contact between the shape memory alloy wire and the conductive part, and only the first current loop is conducted. In the second stage, after the elastic insulating layer is compressed by the shape memory alloy wire, the shape memory alloy wire and the conductive part are in contact, and the first current loop and the second current loop are simultaneously conducted.

[0009] Further, the shape memory alloy wire is hung on the valve, and the shape memory alloy wire has a first branch section on one side of the hanging point and a second branch section on the other side. The first branch section and the second branch section form a gap therebetween, and the conductive part is located between the first branch section and the second branch section.

[0010] Further, the first branch section includes a first main section and a first branch section. The second branch section includes a second main section and a second branch section. The current flows through the first main section, the first branch section, the second branch section, and the second main section in sequence to form a first current loop. The current flows through the first main section, the conductive part, and the second main section in sequence to form a second current loop. The first main section and the second main section form a first contraction unit, the first branch section and the second branch section form a second contraction unit, the current flowing through the first contraction unit is greater than the current flowing through the second contraction unit, so that the temperature of the first contraction unit is higher than the temperature of the second contraction unit, thereby making the contraction amount of the first contraction unit per unit length greater than the contraction amount of the second contraction unit per unit length.

[0011] Further, the resistance value of the conductive part is greater than the resistance value of the second contraction unit.

[0012] Further, the valve is provided with a valve stem and a valve body. The valve stem is at least partially arranged in the valve body, and the valve stem is connected to the shape memory alloy wire. The conductive part is located between the valve stem and the power supply module. The valve stem moves toward the conductive part under the pull of the shape memory alloy wire, and the valve passage opens.

[0013] Furthermore, the portion of the valve stem located inside the valve body is connected to a reset element, which is used to apply a force to the valve stem in the opposite direction to the pulling direction of the shape memory alloy wire.

[0014] In summary, the technical effects achieved by this invention are as follows: To address the problem that uneven heat dissipation can lead to localized stress concentration and fatigue fracture in traditional structures where the alloy wire is heated uniformly throughout, this invention actively adjusts the temperature distribution of the alloy wire by controlling the current density in different sections, reducing the impact of heat dissipation near the joint point, making the contraction more synchronized, and improving motion accuracy and service life. Attached Figure Description

[0015] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0016] Figure 1 A plan view of a shape memory alloy controller provided in an embodiment of the present invention; Figure 2 for Figure 1 A magnified view of a portion of part A (one type of conductive part); Figure 3 for Figure 1 Enlarged view of part A (another conductive part); Figure 4 This is a schematic diagram of the overall structure of the shape memory alloy controller provided in an embodiment of the present invention; Figure 5 A front view of a shape memory alloy controller provided in an embodiment of the present invention; Figure 6 for Figure 5 BB section view; Figure 7 for Figure 5 BB cross-sectional view (excluding cover film); Figure 8 A side view of a shape memory alloy controller provided in an embodiment of the present invention; Figure 9 A side view (excluding the cover film) of a shape memory alloy controller provided for an embodiment of the present invention. Figure 10Another front view of the shape memory alloy controller provided by the embodiment of the present application; Figure 11 A top view of the shape memory alloy controller provided by the embodiment of the present application; Figure 12 Another side view of the shape memory alloy controller provided by the embodiment of the present application; Figure 13 A circuit diagram of the shape memory alloy controller provided by the embodiment of the present application.

[0017] Icon: 100, shape memory alloy wire; 110, first branch; 111, first main section; 112, first sub-section; 120, second branch; 121, second main section; 122, second sub-section; 200, valve; 210, valve rod; 220, valve body; 230, reset member; 300, conductive part; 310, insulating fixed part; 320, conductive layer; 400, elastic insulating layer; 500, insulating plate; 600, cover film; 700, upper shell; 710, clamping protrusion; 800, lower shell; 810, fixed buckle; 820, clamping groove; 10, power supply module. DETAILED DESCRIPTION

[0018] The embodiment provides a shape memory alloy controller, please see Figures 1 to 13 together, the controller comprises at least one control unit, each control unit contains a power supply module, shape memory alloy wire 100, valve 200 and conductive part 300, as Figure 1 shown. Shape memory alloy wire 100 is mechanically connected with valve 200, and forms an electrical circuit with power supply module 10. The alloy wire is divided into first branch 110 and second branch 120 at the connection point of valve 200. Valve 200 has two working states of opening and closing, and the state switching is driven by the length change of shape memory alloy wire 100. Conductive part 300 is arranged in the gap region between first branch 110 and second branch 120, and is not directly connected with valve 200.

[0019] In the structure, the current flows out from power supply module 10 and can return along two paths: the first path passes through the whole first branch 110 and the whole second branch 120 in turn, forming a first current loop; the second path passes through part of first branch 110, conductive part 300 and part of second branch 120 in turn, forming a second current loop. The two loops are electrically connected in parallel, realizing differentiated power supply to different sections of the alloy wire.

[0020] The core of the scheme is to change the current distribution in the shape memory alloy wire 100 by adding the conductive part 300 to construct a parallel bypass. Since the contraction amount of the shape memory alloy is directly related to the current size and the current time, the difference in current distribution will cause the different sections of the alloy wire to produce non-uniform temperature field and strain field. The first current loop flows through the whole length of the alloy wire, ensuring overall basic heating; the second current loop short-circuits part of the alloy wire, so that the current concentrates through the remaining section, thereby accelerating the temperature rise and contraction of the section. This design makes the valve 200 no longer rely on the uniform contraction of the whole alloy wire, but can prioritize the contraction of a certain section by designing the resistance ratio of the two loops, realizing stage-by-stage or intensity-driven driving, which is beneficial to improve the response speed, reduce the overall energy consumption, and alleviate the internal stress problem caused by the uneven expansion of the whole alloy wire due to heating.

[0021] As a variation of the scheme, the conductive part 300 can be made of high-conductivity metal materials such as copper, silver or gold-plated copper alloy to minimize the bypass resistance and ensure effective shunt of the second loop. The shape of the conductive part 300 can be designed as a cylindrical, square or sheet structure according to the installation space, and the contact mode with the alloy wire can be point contact, line contact or surface contact, and the contact pressure can be maintained by mechanical clamping or elastic structure.

[0022] In view of the problem that the conductive part 300 is directly exposed to the installation environment and may cause accidental short circuit due to contact with surrounding metal parts, affecting the reliability of the system, the structure of the conductive part 300 is further limited in this embodiment: The conductive part 300 adopts a composite structure, including an internal insulating fixed part 310 and an external conductive layer 320, as shown in Figure 2 、 Figure 3 The insulating fixed part 310 serves as the core support body and is made of ceramic, engineering plastic or other high-insulation and high-temperature-resistant materials, and its shape matches the overall shape of the conductive part 300. The conductive layer 320 is completely wrapped on the outer surface of the insulating fixed part 310 to form a conductive path. The current flows from the first branch 110 to the surface of the conductive layer 320, and then is transmitted to the second branch 120 through the conductive layer 320 to realize the conduction of the second loop.

[0023] This structure not only ensures good conductivity, but also realizes the electrical isolation of the conductive layer 320 from the external environment through the insulating fixed part 310, effectively preventing the risk of short circuit caused by improper installation or vibration, and improving the working stability of the control unit in complex electromagnetic environment or compact installation space. In addition, the insulating fixed part 310 can also provide mechanical protection for the conductive layer 320, reducing the decline in conductivity caused by friction, oxidation or pollution.

[0024] Furthermore, the conductive layer 320 can be formed through processes such as electroplating, chemical deposition, physical vapor deposition, or bonding metal foil, and its thickness can be adjusted according to current capacity and mechanical strength requirements. The surface of the insulating fixing part 310 can be designed with microstructures such as grooves and protrusions to enhance the adhesion and uniformity of the conductive layer 320. In one variation, the conductive layer 320 can adopt a multi-layer composite structure, for example, the inner layer is a highly conductive copper layer, and the outer layer is an oxidation-resistant and arc-resistant silver alloy or gold-plated layer, to balance conductivity, durability, and contact reliability.

[0025] In some applications, it may be necessary to dynamically control the activation of the second circuit based on the operating stage of the valve 200. For example, in the initial stage of valve 200 startup, only the first circuit needs to operate to provide initial displacement, and the second circuit is only connected for fine-tuning or maintaining the position when approaching the target position. To achieve this staged control, this embodiment designs the contact state between the shape memory alloy wire 100 and the conductive part 300.

[0026] This embodiment provides two contact strategies: The first type is the constant contact type, meaning that regardless of whether the shape memory alloy wire 100 is energized or not, it always maintains physical contact and electrical connection with the conductive part 300, and the second circuit is always in a ready-to-conduct state, with its on / off state controlled by the power supply module 10. The first strategy is simple to control, has a fast response, and is suitable for applications where timing requirements are not stringent.

[0027] The second type is deformation-triggered, where initially, there is a tiny gap between the shape memory alloy wire 100 and the conductive part 300, and they are not in contact. When the alloy wire is energized, heated, and shrinks to a certain length, it contacts the conductive part 300 and connects the second circuit. This second strategy achieves automatic triggering based on the deformation of the alloy wire itself, without the need for external sensors or complex control circuits, thus improving the system's autonomy and reliability. The deformation-triggered contact can be set by adjusting the initial gap size, the alloy wire preload, or the position of the conductive part 300, thereby linking the valve 200 stroke with the timing of the second circuit's activation.

[0028] As an optional implementation, elastic conductive contacts, such as spring pins or conductive rubber, can be provided on the contact surface of the conductive part 300 or at corresponding positions on the alloy wire to compensate for manufacturing tolerances, ensure contact reliability, and reduce poor contact caused by vibration. Furthermore, a lubricating or anti-oxidation coating can be applied to the contact area to maintain a stable contact resistance over a long period.

[0029] While deformation-triggered contacts can achieve stage control, improper gap control may lead to contact instability or poor trigger point repeatability. To provide a more reliable and precise stage switching mechanism, this embodiment introduces an elastic insulating layer 400 between the shape memory alloy wire 100 and the conductive part 300, as described above. Figure 3As shown.

[0030] In its initial state, the elastic insulating layer 400 completely isolates the alloy wire from the conductive part 300, at which point only the first current loop is conductive. The elastic insulating layer 400 is made of materials such as silicone rubber, fluororubber, or high-temperature resistant polymer foam, possessing a certain degree of compressibility and elastic recovery. When the shape memory alloy wire 100 is energized and heated, and begins to shrink, it applies gradually increasing pressure to the elastic insulating layer 400. In the first stage, the pressure is insufficient to completely compress the insulating layer, and the two remain isolated. As the shrinkage increases, the second stage begins, where the insulating layer is compressed until its thickness is less than the initial distance between the alloy wire and the conductive part 300, allowing the alloy wire to directly contact the conductive part 300, thus opening the second current loop.

[0031] This design uses the compression stroke of the elastic insulating layer 400 as a mechanical switch. Its triggering pressure is closely related to the material hardness, thickness, and shape of the elastic insulating layer 400, and can be precisely set through design. Due to the good force-displacement repeatability of the elastic material, this triggering mechanism has high consistency and reliability. Furthermore, the elastic insulating layer 400 also acts as a buffer and vibration damper, absorbing some of the impact energy during the contraction of the alloy wire, which helps protect the conductive contact surfaces and extend the component's lifespan.

[0032] In further improvements, the elastic insulating layer 400 can be designed with nonlinear stiffness characteristics, such as by using a variable thickness structure or composite materials, resulting in lower stiffness in the initial stage of compression and increased stiffness in the later stage, thereby achieving two-stage force control that better matches the valve 200's action curve. Alternatively, micro-conductive particles or pressure-sensitive materials can be embedded in the elastic insulating layer 400. When compressed to a certain threshold, the conductivity changes abruptly, enabling electrical signal feedback to monitor the contraction state of the alloy wire.

[0033] In order to achieve high-efficiency transmission of shape memory alloy wire 100 to valve 200 and facilitate the integrated installation of conductive part 300, this embodiment optimizes the connection method and overall layout of alloy wire and valve 200.

[0034] In this embodiment, the shape memory alloy wire 100 is bent at the connection point of the valve 200 to form a U-shaped, V-shaped, or ring-shaped hook structure, which is directly hooked or sleeved onto the specially designed groove, protrusion, or pin of the valve 200. The alloy wire is naturally divided into a first segment 110 on one side of the valve 200 and a second segment 120 on the other side, with the hook point as the boundary. The first segment 110 and the second segment 120 extend on both sides of the hook point, that is, the first segment 110 and the second segment 120 are arranged parallel to each other and form a gap. The conductive part 300 is arranged within this gap, with its two ends facing the first segment 110 and the second segment 120 respectively, so as to form an electrical connection with them.

[0035] The U-shaped hook structure allows the contraction force of the alloy wire to act directly on the force-bearing point of the valve 200, resulting in a short force transmission path, high efficiency, and easy installation. The gap not only provides space for the conductive part 300 but also allows the first and second sections 110 to deform relatively independently during thermal contraction, reducing mutual interference and facilitating non-uniform contraction control. Furthermore, the gap facilitates heat dissipation and prevents the alloy wires from contacting each other due to expansion at high temperatures, thus avoiding short circuits.

[0036] In a preferred embodiment, a guide groove or limiting structure can be provided on the valve 200 to ensure that the U-shaped engagement point moves along a predetermined trajectory during operation, thereby improving the accuracy of the operation. The conductive part 300 can be fixed in the center of the gap by an insulating bracket, and its position can be finely adjusted to optimize the contact relationship with the alloy wire. In a variation, the width of the gap can be designed to be adjustable to accommodate alloy wires of different specifications or to adjust the triggering conditions.

[0037] While the aforementioned dual-segment structure achieves basic current shunting, a more precise control over the contraction behavior of different functional segments is required. For example, the segment far from valve 200 can contract rapidly to initiate the action, while the segment close to valve 200 can contract slowly to provide auxiliary displacement or positioning. In such cases, a more detailed division of the current path is necessary.

[0038] Therefore, in this embodiment, the first branch segment 110 is further divided into a first main road segment 111 and a first branch road segment 112 connected in series, and the second branch segment 120 is further divided into a second main road segment 121 and a second branch road segment 122 connected in series, as follows. Figure 13 As shown. The first main road section 111 and the second main road section 121 are spatially far from the valve 200 connection point and are considered the main drive sections; the first branch road section 112 and the second branch road section 122 are relatively close to the valve 200 and are considered auxiliary sections. The conductive part 300 is connected between the first main road section 111 and the second main road section 121, and is actually connected in parallel at both ends of the branch road formed by the first branch road section 112 and the second branch road section 122 connected in series.

[0039] In this circuit model, after the current flows out of the power supply module 10, it splits into two streams at the end of the first main section 111: one stream flows through the first main section 111 and continues through the conductive part 300 and the second main section 121 back to the power source (i.e., the second current loop); the other stream flows sequentially through the first main section 111, the first branch section 112, the second branch section 122, and the second main section 121 back to the power source (i.e., the first current loop). Clearly, the current A flowing through the first main section 111 and the second main section 121 is the sum of the current A1 flowing through the conductive part 300 and the current A2 flowing through the first branch section 112 and the second branch section 122. Therefore, the current density and heat generation power of the first main section 111 and the second main section 121 (collectively referred to as the first contraction unit, i.e., the main drive section) will be higher than those of the first branch section 112 and the second branch section 122 (collectively referred to as the second contraction unit, i.e., the auxiliary section).

[0040] Based on the characteristics of shape memory alloys, within the same time frame, the section with higher heating power experiences a faster temperature rise, more complete phase change, and greater shrinkage per unit length. Therefore, the first shrinkage unit will shrink significantly before the second shrinkage unit, thus allowing it to be designed to handle the primary action of opening or closing the valve 200; the second shrinkage unit then shrinks subsequently, and can be used for precise positioning at the end of the stroke, force maintenance, or compensation for temperature drift. This clear sequence of primary and secondary shrinkage helps improve the response speed and positioning accuracy of the valve 200, and the action curve can be optimized by adjusting the resistance ratio of each segment.

[0041] To further enhance this effect, the resistance of the conductive part 300 can be designed to be greater than the resistance of the second shrinking unit (i.e., the total resistance of the first branch 112 and the second branch 122 in series). According to the current division principle of parallel circuits, the branch with higher resistance has lower current. This ensures that most of the current still flows through the second shrinking unit, giving it the necessary shrinking capacity, while keeping the current flowing through the branch of the conductive part 300 smaller, avoiding excessive current division that could lead to insufficient current in the main drive section, i.e., A1 less than A2. More importantly, this design allows the total current A of the first shrinking unit (equal to the current A2 flowing through the second shrinking unit plus the current A1 flowing through the conductive part 300) to be precisely controlled at a high level, thereby stably achieving its design goal of priority and rapid shrinkage. Through careful matching of resistance values, the shrinkage amount and timing of the two shrinking units can be coordinated, avoiding excessive stress inside the alloy wire or jamming of the valve 200 due to asynchronous shrinkage.

[0042] In order to efficiently convert the linear contraction of the shape memory alloy wire 100 into the opening and closing action of the valve 200, this embodiment provides a specific implementation of the direct-acting valve 200 structure.

[0043] The valve 200 includes a valve body 220 and a valve stem 210 that is axially movable within the valve body 220, such as...Figure 6 , Figure 7 As shown. One end of the valve stem 210 extends into the valve body 220, and its end or side is provided with a sealing surface, which cooperates with the valve seat on the valve body 220 to cut off or connect the fluid passage; the other end or the external protruding part of the valve stem 210 is connected to the shape memory alloy wire 100. The conductive part 300 is usually fixed on the valve body 220 or an adjacent bracket, and its position corresponds to a point on the movement path of the valve stem 210, or is located in the plane where the alloy wire is arranged. When the alloy wire is energized and contracts, it directly pulls the valve stem 210 in the direction that moves it away from the valve seat, thereby opening the valve 200 passage.

[0044] This direct-acting structure has a short transmission chain, low frictional loss, rapid response, and facilitates calculation of the relationship between stroke and alloy wire shrinkage. To achieve automatic reset of valve 200 to its initial state (e.g., normally closed or normally open) after power failure, this embodiment includes a reset element 230 on the valve stem 210. Figure 6 , Figure 7 As shown. A common reset element 230 is a spring: a compression spring, tension spring, or torsion spring is installed on the portion of the valve stem 210 located within the valve body 220. The preload of the spring is in the opposite direction to the tension of the alloy wire. When the alloy wire is energized, its contraction force overcomes the spring force, driving the valve stem 210 to move; when the power is off and the wire cools, it extends, and the spring force pushes the valve stem 210 back to its original position. The spring reset method is simple in structure, reliable, and the reset force is adjustable.

[0045] In applications where multiple valves 200 need to be controlled simultaneously or sequentially, such as vehicle seat massage pneumatic systems and vehicle seat pneumatic support systems, integrating multiple control units as described in the foregoing embodiments into a single controller can significantly improve system compactness and reliability.

[0046] To accommodate all control units and internal structures, the controller has an upper housing 700 and a lower housing 800, such as Figure 4 As shown. The upper and lower housings are typically made of metal (such as aluminum alloy with surface insulation) or high-strength engineering plastics, connected by snaps, screws, or welding to form a single integrated chamber. The housings provide mechanical strength support, electromagnetic shielding, environmental protection, and interfaces for easy overall installation. This modular integrated design facilitates mass production, testing, and maintenance. Users can configure the number of control units according to their needs, improving the product's flexibility and adaptability.

[0047] Specifically, multiple control units are located within the cavity formed by the upper housing 700 and the lower housing 800. This cavity creates a sealed space, effectively isolating external dust, moisture, and other impurities, protecting internal components from corrosion, and reducing the impact of external vibrations on the control units. The upper housing 700 and the lower housing 800 are connected using a snap-fit ​​design. The upper housing 700 has snap-fit ​​protrusions 710, and the lower housing 800 has snap-fit ​​grooves 820. Figure 9 , Figure 12 As shown, the snap-fit ​​protrusion 710 is adapted to the shape of the snap-fit ​​groove 820. By embedding the snap-fit ​​protrusion 710 into the snap-fit ​​groove 820, a quick snap-fit ​​connection between the upper housing 700 and the lower housing 800 is achieved. This connection method requires no additional fasteners, is convenient for installation and disassembly, and ensures the stability of the housing connection. Obviously, a structure can also be adopted in which the upper housing 700 has a snap-fit ​​groove 820 and the lower housing 800 has a snap-fit ​​protrusion 710.

[0048] To facilitate quick installation and fixation of the shape memory alloy controller and adapt to different installation scenarios, the lower housing 800 is also equipped with fixing clips 810, such as... Figure 12 As shown, the fixing clip 810 is equipped with a U-shaped opening. The size of the U-shaped opening is adapted to the fixing component at the installation position. Through the U-shaped opening, the shape memory alloy controller can be quickly installed in the corresponding position by snapping it on, eliminating the need for complex operations such as drilling and bolt fixing, thus improving installation efficiency. The fixing clip 810 has a certain degree of elasticity, which can be achieved through material and structural design. The elastic design allows the fixing clip 810 to deform slightly during installation, fitting snugly against the fixing component at the installation position. After installation, it relies on elastic reset to firmly lock onto the fixing component, ensuring installation stability and preventing the controller from loosening or falling off. Furthermore, the inner wall of the U-shaped opening is provided with a groove, which can cooperate with the protrusion on the fixing component at the installation position to form a secondary positioning, further improving installation reliability and preventing the shape memory alloy controller from slipping off due to vibration, collision, or other factors during operation.

[0049] For scenarios requiring simultaneous control of multiple valves or multiple stations of the same valve, multiple control units can be set up. Each control unit is isolated from the others by an insulating board 500. The insulating board 500 can be made of epoxy resin board, which has good insulation performance and structural strength, effectively preventing electrical interference between multiple control units and ensuring that each control unit can operate independently and stably. Simultaneously, each control unit's shape memory alloy wire is covered with a cover film 600. The cover film 600 can be made of high-temperature resistant, waterproof, and dustproof polyimide film, effectively protecting the shape memory alloy wire from dust, moisture, oil, and other impurities, preventing corrosion, and reducing friction and wear between the alloy wire and other components, thus extending the service life of the alloy wire. Figure 4 , Figure 6 As shown.

[0050] The pneumatic assembly employing a shape memory alloy controller with dual-loop, segmented contraction control capabilities offers superior control performance. For example, in constant-voltage power supply mode, the current shunted in the conductive section 300 increases the current in the main drive section, resulting in faster heating and a shorter opening / closing response time for valve 200. Simultaneously, the shunting of some current reduces the current flowing through the second contraction unit, shortening the heating time and helping to lower the steady-state temperature of these sections, potentially improving the overall fatigue life of the alloy wire. In constant-current power supply mode, the current shunted in the conductive section 300 reduces the current flowing through non-critical sections, directly lowering their heat output and contributing to energy saving and temperature rise reduction. The control system can also utilize these multi-stage contraction characteristics to achieve advanced motion control functions such as fast-forward-slow-forward and high-speed-precision positioning of the actuator.

[0051] This pneumatic assembly can be widely used in automotive active suspension, transmission control, brake assist systems, precision assembly in industrial automation, fixture control, and fluid management of medical devices, providing a pneumatic solution that is fast-responding, compact, precise in control, and highly reliable.

[0052] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A shape memory alloy controller, characterized in that: Includes at least one control unit, said control unit comprising: Power supply module (10); A shape memory alloy wire (100) is electrically connected to the power supply module (10) and connected to the valve (200). The shape memory alloy wire (100) is divided into a first segment (110) and a second segment (120) at the valve (200). The valve (200) has an open state and a closed state. The shape memory alloy wire (100) changes length after being energized and heated to drive the valve (200) to switch on / off states. A conductive part (300) is located between the first branch (110) and the second branch (120); The current flows from the power supply module (10) through the entire first branch (110) and the entire second branch (120) in sequence, and then flows back to the power supply module (10) to form a first current loop; The current flows from the power supply module (10) through part of the first branch (110), the conductive part (300), and part of the second branch (120) in sequence, and then flows back to the power supply module (10) to form a second current loop.

2. The shape memory alloy controller according to claim 1, characterized in that, The conductive part (300) includes: An insulating fixing part (310) is provided inside the conductive part (300); A conductive layer (320) is disposed outside the insulating fixing part (310). Current passes through the first branch (110), through the conductive layer (320), and then to the second branch (120).

3. The shape memory alloy controller according to claim 1, characterized in that: The conductive part (300) is made of metal and is used to form a second current loop.

4. The shape memory alloy controller according to claim 1, characterized in that: The shape memory alloy wire (100) is in contact with and electrically connected to the conductive part (300) in both the energized and de-energized states; or, The shape memory alloy wire (100) does not contact the conductive part (300) when it is not energized.

5. The shape memory alloy controller according to claim 1, characterized in that: An elastic insulating layer (400) is provided between the shape memory alloy wire (100) and the conductive part (300). In the first stage, the elastic insulating layer (400) isolates the contact between the shape memory alloy wire (100) and the conductive part (300), and only the first current loop is open; In the second stage, after the elastic insulating layer (400) is compressed by the shape memory alloy wire (100), the shape memory alloy wire (100) and the conductive part (300) come into contact, and the first current circuit and the second current circuit are simultaneously turned on.

6. The shape memory alloy controller according to claim 1, characterized in that: The shape memory alloy wire (100) is attached to the valve (200), with one side of the attachment point being the first branch (110) and the other side being the second branch (120). A gap is formed between the first branch (110) and the second branch (120), and the conductive part (300) is located between the first branch (110) and the second branch (120).

7. The shape memory alloy controller according to claim 6, characterized in that: The first branch section (110) includes the first main road section (111) and the first branch road section (112). The second branch (120) includes the second main road section (121) and the second sub-road section (122); The current flows sequentially through the first main section (111), the first branch section (112), the second branch section (122), and the second main section (121) to form a first current loop; The current flows sequentially through the first main circuit section (111), the conductive part (300), and the second main circuit section (121) to form a second current loop; The first main road segment (111) and the second main road segment (121) form a first contraction unit, and the first branch road segment (112) and the second branch road segment (122) form a second contraction unit. The current flowing through the first contraction unit is greater than the current flowing through the second contraction unit so that the temperature of the first contraction unit is higher than the temperature of the second contraction unit, thereby making the contraction amount of the first contraction unit per unit length greater than the contraction amount of the second contraction unit per unit length.

8. The shape memory alloy controller according to claim 7, characterized in that: The resistance value of the conductive part (300) is greater than the resistance value of the second shrinking unit.

9. The shape memory alloy controller according to claim 1, characterized in that: The valve (200) is provided with a valve stem (210) and a valve body (220). The valve stem (210) is at least partially disposed within the valve body (220), and the valve stem (210) is connected to the shape memory alloy wire (100); The conductive part (300) is located between the valve stem (210) and the power supply module. The valve stem (210) moves toward the conductive part (300) under the pull of the shape memory alloy wire (100), and the passage of the valve (200) is opened.

10. The shape memory alloy controller according to claim 9, characterized in that: The portion of the valve stem (210) located inside the valve body (220) is connected to a reset member (230), which is used to apply a force to the valve stem (210) in the opposite direction to the pulling direction of the shape memory alloy wire (100).

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