Short process preparation method of SMA spring and application thereof
By using hot-rolling to wind SMA springs at Af+120℃~Af+240℃, the problem of dimensional instability after cold rolling was solved, achieving high yield and low-cost mass production, and improving manufacturing efficiency.
Patent Information
- Application Number
- CN202411739318.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-29
- Publication Date
- 2026-05-29
AI Technical Summary
In existing technologies, shape memory alloy springs have unstable dimensions after cold rolling, resulting in low product qualification rates, high production costs, and difficulty in achieving mass production.
SMA springs are wound using a hot-rolling method at temperatures ranging from Af+120℃ to Af+240℃. The process involves directly winding the springs using equipment such as a fully automatic wire feeder, a tunnel-type heat preservation furnace, and a CNC universal spring machine, thus avoiding secondary mold shaping and heat treatment.
It improves the dimensional stability and yield of SMA springs, increasing them from 50%–60% to 95%–98%, reduces production costs, and increases production efficiency by 10 times, making it suitable for mass production.
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Figure CN122099189A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of fluid control technology, specifically to a short-process manufacturing method for SMA springs and their applications. Background Technology
[0002] Shape memory alloys have attracted widespread attention due to their unique elasto-thermal effect, and are therefore widely used in engineering components, medical components, and intelligent control components. Among them, shape memory alloy springs, as temperature-sensing elements, have garnered significant attention for their application in fluid control valves, where their expansion and contraction at different temperatures enable feedback regulation to achieve dynamic balance. This not only simplifies and improves valve core structures but also provides extremely fast response speeds in fluid control, meeting users' needs for stepless fine-tuning.
[0003] Existing shape memory alloy springs are mostly cold-rolled during processing. However, the deformation of cold-rolled springs is unstable, meaning the dimensional changes deviate significantly from the design dimensions, resulting in low product yield, high production costs, and unsuitability for mass production. Manufacturers typically perform secondary processing on springs within the allowable error range, while those exceeding the error range are directly remelted into alloy wire. Specifically, the secondary processing relies on shaping molds for heat treatment; however, due to the small size of shape memory alloy springs, using shaping molds presents problems such as a large number of molds, high process difficulty, high manual operation requirements, and low production efficiency. In other words, using shaping molds for direct secondary processing requires significant investment in both labor and equipment costs for shape memory alloy spring manufacturers, making mass production impossible. Summary of the Invention
[0004] The purpose of this invention is to provide a short-process manufacturing method for SMA springs and its application, which solves the technical problems of unstable dimensions of cold-rolled shape memory alloy springs, low product qualification rate of directly produced products, and high production costs due to the need for secondary shaping.
[0005] To achieve the above objectives, the present invention proposes the following technical solution:
[0006] Firstly, a short-process manufacturing method for SMA springs is proposed, which uses a hot-rolling method to form SMA springs. The hot-rolling method involves winding SMA alloy wire into SMA springs at a winding forming temperature of Af+120℃~Af+240℃.
[0007] Furthermore, the winding forming temperature is achieved as follows:
[0008] An SMA spring winding equipment is constructed, comprising a fully automatic wire feeder, a tunnel-type heat preservation furnace, and a CNC universal spring machine arranged sequentially.
[0009] The fully automatic wire feeder is used for automatic wire feeding, providing speed compensation for SMA alloy wire, and providing abnormal stop and alarm functions. The furnace chamber of the tunnel insulation furnace uses PID temperature control to preheat the mandrel of the CNC universal spring machine, so that the temperature of the SMA alloy wire conducted by the mandrel during the winding of the forming spring rises to Af+120℃~Af+240℃.
[0010] Furthermore, the winding forming temperature is achieved as follows:
[0011] An SMA spring winding equipment is constructed, comprising a constant temperature environment chamber and a spring compression machine installed inside the constant temperature environment chamber;
[0012] The constant temperature environment chamber includes an outer shell made of cold-rolled steel plate, an insulation layer made of ceramic fiber disposed inside the outer shell, a heating element, and an Omron E5CC 850 digital temperature controller. The Omron E5CC 850 digital temperature controller controls the temperature inside the constant temperature environment chamber to the winding forming temperature of the SMA spring, Af+120℃~Af+240℃.
[0013] Furthermore, the winding forming temperature is achieved as follows:
[0014] An SMA spring winding equipment is constructed, which includes a CNC universal spring machine and a high-frequency induction coil. The high-frequency induction coil is located on the mandrel side near the CNC universal spring machine, and a heating space is formed inside the high-frequency induction coil.
[0015] When the mandrel winds the spring, the CNC universal spring machine pre-feeds an SMA alloy wire of a set specification into the heating space. The SMA alloy wire is heated to Af+120℃~Af+240℃ in the heating space. After heating is completed, the wire feeding wheel of the CNC universal spring machine reverses and returns the heated SMA alloy wire to the spring winding processing area for processing.
[0016] Further steps include the following:
[0017] 1) After installing the SMA alloy wire spool on the spring machine;
[0018] 2) Start the spring machine, feed the SMA alloy wire to the preheating zone for preheating, and then feed the preheated SMA alloy wire to the spring winding processing area;
[0019] 3) SMA springs are produced by winding at a winding temperature of Af+120℃~Af+240℃ according to the preset length and shape.
[0020] Furthermore, the diameter of the SMA alloy wire in the SMA alloy wire spool is 0.2 to 3.0 mm.
[0021] Furthermore, the conveying speed of the SMA alloy wire is 12.5–125 mm / s.
[0022] Furthermore, the SMA alloy wire is preheated in the preheating zone for 24–240 seconds and for 3–6 meters.
[0023] Secondly, the application of SMA springs prepared using the aforementioned short-process method in fluid control system valves is proposed.
[0024] As can be seen from the above technical solutions, the technical solutions of the present invention have achieved the following beneficial effects:
[0025] This invention proposes a short-process manufacturing method for SMA springs and its application. The method includes: 1) installing an SMA alloy wire spool on a spring machine; 2) starting the spring machine, conveying the SMA alloy wire to the preheating zone for preheating, and conveying the preheated SMA alloy wire to the spring winding processing zone; 3) producing SMA springs according to a preset length and shape under a winding forming temperature of Af+120℃~Af+240℃. This invention proposes a hot-rolling method to directly wind and form SMA springs at a winding temperature of Af+120℃~Af+240℃. This hot-rolling process ensures dimensional stability after forming. Compared to the traditional cold-rolling method, which involves first cold-rolling the spring, then shaping it with a mold and undergoing heat treatment to produce high-precision SMA springs with a yield rate of only 50%~60%, the hot-rolling process can increase the yield rate of high-precision SMA springs to 95%~98%. This process eliminates the mold shaping and heat treatment steps, reducing production steps, saving labor costs, and improving operational safety. For manufacturers, this process increases production capacity tenfold and has room for continuous optimization, significantly improving the manufacturing efficiency of SMA springs.
[0026] Compared to the traditional cold-rolling method, the short-process manufacturing method of SMA springs in this invention transforms the microstructure from the traditional austenite-martensite + dislocation-austenitization-dislocation shaping process to a short-process transformation from austenite-plastic deformation shaping. This effectively shortens the manufacturing process of SMA springs, significantly reduces costs, and produces SMA springs with highly stable technical performance.
[0027] It should be understood that all combinations of the foregoing concepts and the additional concepts described in more detail below can be considered part of the inventive subject matter of this disclosure, provided that such concepts do not contradict each other.
[0028] The foregoing and other aspects, embodiments, and features of the teachings of the present invention will be more fully understood from the following description in conjunction with the accompanying drawings. Other additional aspects of the invention, such as features and / or beneficial effects of exemplary embodiments, will become apparent from the following description or may be learned through practice of specific embodiments according to the teachings of the present invention. Attached Figure Description
[0029] The accompanying drawings are not drawn to scale. In the drawings, each identical or nearly identical component shown in the various figures may be denoted by the same reference numeral. For clarity, not every component is labeled in each figure. Embodiments of various aspects of the invention will now be described by way of example and with reference to the accompanying drawings, wherein:
[0030] Figure 1 The graph showing the change in height of the SMA spring as a function of temperature obtained in Example 1;
[0031] Figure 2 The graph showing the change in height of the SMA spring as a function of temperature obtained in Example 5;
[0032] Figure 3 To obtain the SMA spring height variation curve with temperature for Comparative Example 2;
[0033] Figure 4 To obtain the SMA spring height variation curve with temperature for Comparative Example 5;
[0034] Figure 5 The curve of SMA spring height versus temperature was obtained for Comparative Example 9. Detailed Implementation
[0035] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention without creative effort are within the scope of protection of the present invention. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by those skilled in the art to which this invention pertains.
[0036] The terms "first," "second," and similar words used in the specification and claims of this patent application do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, unless the context clearly indicates otherwise, the singular forms of "an," "a," or "the," etc., do not indicate a quantity limitation, but rather indicate the presence of at least one. Terms such as "comprising" or "including" mean that the element or object preceding "comprising" encompasses the features, integrals, steps, operations, elements, and / or components listed following "comprising" or "including," and do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or collections thereof.
[0037] Based on the elasto-thermal effect of SMA springs, they have excellent application prospects in the field of fluid control. However, at present, SMA springs are mainly processed by cold rolling followed by secondary mold shaping. On the one hand, the spring deformation is uncontrollable and cannot be used directly after cold rolling. On the other hand, secondary processing requires different molds to be configured according to the spring and heat treatment, which consumes time and manpower costs, and the production efficiency is low. Therefore, it is necessary to propose a new manufacturing scheme for SMA springs to reduce the production cost investment of enterprises and improve manufacturing efficiency.
[0038] This invention proposes a short-process manufacturing method for SMA springs using hot-rolling, specifically, winding SMA alloy wire into SMA springs at a winding forming temperature of Af+120℃~Af+240℃. The method includes the following steps: 1) After installing an SMA alloy wire spool on a spring machine, the diameter of the SMA alloy wire on the spool is 0.2~3.0mm; 2) Starting the spring machine, conveying the SMA alloy wire to a preheating zone for preheating, and then conveying the preheated SMA alloy wire to the spring winding processing zone. The conveying speed of the SMA alloy wire is 12.5~125mm / s, and the preheating time in the preheating zone is 24~240s, with a preheating length of 3~6m; 3) Under the winding forming temperature of Af+120℃~Af+240℃, producing SMA springs according to a preset length and shape.
[0039] The aforementioned method for achieving the winding forming temperature of SMA springs at Af+120℃~Af+240℃ during hot rolling involves, for example, constructing an SMA spring winding equipment. This equipment includes a fully automatic wire feeder, a tunnel-type heat-insulating furnace, and a CNC universal spring machine arranged sequentially. The fully automatic wire feeder is used for automatic wire feeding, providing speed compensation for the SMA alloy wire, and providing abnormal stop and alarm functions. The tunnel-type heat-insulating furnace uses PID temperature control to preheat the mandrel of the CNC universal spring machine, so that the temperature of the SMA alloy wire, which is transferred by the mandrel during spring winding, rises to Af+120℃~Af+240℃. During spring winding, the alloy wire is heated to the target temperature.
[0040] Alternatively, the winding forming temperature can be achieved by: constructing an SMA spring winding equipment, which includes a constant temperature environment chamber and a spring compression machine installed inside the chamber; the constant temperature environment chamber includes a shell made of cold-rolled steel plate, an insulation layer made of ceramic fiber installed inside the shell, a heating element, and an Omron E5CC 850 digital temperature controller, which controls the temperature inside the chamber to the winding forming temperature of the SMA spring, Af+120℃~Af+240℃. This ensures that all components of the machine processing the SMA spring are within the target temperature environment, achieving the winding of the alloy wire at the target temperature.
[0041] Alternatively, the winding forming temperature can be achieved as follows: An SMA spring winding device is constructed, comprising a CNC universal spring machine and a high-frequency induction coil. The high-frequency induction coil is positioned near the mandrel side of the CNC universal spring machine, forming a heating space inside the coil. When the mandrel winds the spring, the CNC universal spring machine pre-feeds an SMA alloy wire of a set specification into the heating space. The SMA alloy wire is heated to Af+120℃~Af+240℃ within the heating space. After heating, the feed wheel of the CNC universal spring machine reverses, returning the heated SMA alloy wire to the spring winding processing area for further processing. This allows the portion of the SMA alloy wire to be processed into an SMA spring to be preheated to the target temperature before further processing. This invention is not limited to the three methods for achieving the winding temperature of SMA alloy wire proposed above.
[0042] The following detailed description, in conjunction with specific embodiments and accompanying drawings, further illustrates the short-process manufacturing method for SMA springs disclosed in this invention and its applications. Table 1 shows the finished dimensions of SMA springs made from SMA alloy wires of different diameters.
[0043] Table 1 shows the SMA spring size specifications.
[0044]
[0045]
[0046] Example 1
[0047] 1) After installing the SMA alloy wire spool on the spring machine, the diameter of the SMA alloy wire on the spool is 1.75mm; 2) Start the spring machine, convey the SMA alloy wire to the preheating zone for preheating, and then convey the preheated SMA alloy wire to the spring winding processing zone. The conveying speed of the SMA alloy wire is 70mm / s, and the preheating time of the SMA alloy wire in the preheating zone is 100s, with a preheating length of 3m; 3) Under the condition of a winding forming temperature of 145℃ (i.e., the material Af+135℃), produce SMA springs of specification 3 according to the preset length and shape. The winding forming temperature is achieved by using an SMA spring winding equipment consisting of a fully automatic wire feeder, a tunnel-type heat preservation furnace, and a CNC universal spring machine, based on equipment cost and process implementation, i.e., a high-temperature mandrel heat transfer method.
[0048] Examples 2-3 have the same preparation process parameters as Example 1, and are all used to prepare SMA springs of specification 3 to verify the dimensional stability of SMA springs prepared by the hot-rolling process in this case. The only difference between Examples 4-8 and Examples 1-3 is the spring specification, SMA alloy wire diameter, wire feeding speed, preheating time, preheating length and winding temperature. Other conditions and parameters remain unchanged, as shown in Table 2 below.
[0049] Table 2 shows the process parameters for manufacturing SMA springs in Examples 1-8.
[0050] Serial Number Molding method preheating time Preheating length Winding temperature wire diameter Wire feeding speed Example 1 Hot roll 100s 3m 145℃ 1.75 70mm / s Example 2 Hot roll 100s 3m 145℃ 1.75 70mm / s Example 3 Hot roll 100s 3m 145℃ 1.75 70mm / s Example 4 Hot roll 100s 3m 130℃ 1.75 70mm / s Example 5 Hot roll 100s 3m 145℃ 1.2 70mm / s Example 6 Hot roll 100s 3m 145℃ 1.75 100mm / s Example 7 Hot roll 80s 3m 145℃ 1.75 70mm / s Example 8 Hot roll 100s 4.8m 145℃ 1.75 70mm / s
[0051] The difference between Comparative Examples 1-3 and Example 1 is that they use SMA alloy wires of different diameters and cold-rolling forming methods at different wire feeding speeds. The difference between Comparative Examples 4-13 and Example 1 is only in the SMA alloy wire diameter, wire feeding speed, preheating time, preheating length and winding temperature. Other conditions and parameters remain unchanged, as shown in Table 3 below.
[0052] Table 3 shows the process parameters for manufacturing SMA springs in Comparative Examples 1-16.
[0053] Serial Number Molding method preheating time Preheating length Winding temperature wire diameter Wire feeding speed Comparative Example 1 Cold roll / / / 1.75 70mm / s Comparative Example 2 Cold roll / / / 1.2 70mm / s Comparative Example 3 Cold roll / / / 1.75 100mm / s Comparative Example 4 Hot roll 10s 3m 145℃ 1.75 70mm / s Comparative Example 5 Hot roll 300s 3m 145℃ 1.75 70mm / s Comparative Example 6 Hot roll 100s 1.5m 145℃ 1.75 70mm / s Comparative Example 7 Hot roll 100s 10m 145℃ 1.75 70mm / s Comparative Example 8 Hot roll 100s 3m 20℃ 1.75 70mm / s Comparative Example 9 Hot roll 100s 3m 300℃ 1.75 70mm / s Comparative Example 10 Hot roll 100s 3m 145℃ 0.1 70mm / s Comparative Example 11 Hot roll 100s 3m 145℃ 3.8 70mm / s Comparative Example 12 Hot roll / 3m 145℃ 1.75 8mm / s Comparative Example 13 Hot roll / 3m 145℃ 1.75 150mm / s
[0054] The dimensions and frequency of wire breakage / stripping of the SMA springs obtained in Examples 1-8 and Comparative Examples 1-13 are shown in Tables 4 and 5 below. The performance of the SMA springs was measured as follows: Figure 1-5 As shown;
[0055] Table 4 shows the dimensional performance data of the SMA springs obtained in Examples 1-8.
[0056] Serial Number Free height outer diameter Pitch Frequency of fiber breakage and shedding Mold shaping Example 1 23.08 8.78 3.53 none no Example 2 22.98 8.73 3.54 none no Example 3 22.93 8.77 3.53 none no Example 4 23.01 8.75 3.58 none no Example 5 23.04 6 4.21 none no Example 6 23.09 8.74 3.53 none no Example 7 23.07 8.77 3.54 none no Example 8 23.07 8.77 3.55 none no
[0057] Combination Figure 1 As shown, compared to traditional cold rolling forming, this invention hot-rolls SMA springs at Af+120℃~Af+240℃, innovatively transforming the microstructure of SMA alloy wire from the traditional "austenite-martensite + dislocation-austenitization-dislocation shaping" process to a short-flow change process of "austenite-plastic deformation shaping". Therefore, SMA springs with controllable deformation can be obtained, namely the SMA spring shown in Example 1, whose height changes stably with temperature in the range of 25~65℃. The stroke characteristics and phase transformation temperature characteristics of the hot-rolled SMA spring fully meet the preparation objectives. Compared with the traditional method, the SMA spring prepared by this invention has a shorter preparation process, controllable deformation, low cost, and is suitable for mass production.
[0058] The SMA springs obtained in Examples 2 and 3 showed dimensional errors consistent with those in Example 1, meeting the manufacturing standards. Their stroke curves were similar to those of the spring in Example 1, with strokes ≥6mm within a temperature range of 25–65℃. Combined with Examples 1 and 4-8, it was demonstrated that SMA springs with the target performance could be obtained by changing the hot-rolling forming parameters at the hot-rolling temperature of Example 1. Figure 1 and Figure 2 Within the hot-rolling temperature parameter range defined by this invention, SMA springs of different specifications can be prepared with stable stroke characteristics and phase transition temperature characteristics to meet the requirements of the working objectives.
[0059] Table 5 shows the dimensional and performance data of the SMA springs obtained in Comparative Examples 1-16.
[0060] Serial Number Free height outer diameter Pitch Frequency of fiber breakage and shedding Mold shaping Comparative Example 1 21.88 9.25 2.9 frequently yes Comparative Example 2 22.85 6.11 4.08 often yes Comparative Example 3 / / / frequently / Comparative Example 4 22.74 9.01 3.59 often no Comparative Example 5 23.03 8.77 3.53 rare no Comparative Example 6 23.1 8.72 3.57 often no Comparative Example 7 23.11 8.72 3.58 rare no Comparative Example 8 23.67 8.5 3.84 frequently no Comparative Example 9 23.04 8.75 3.55 rare no Comparative Example 10 / / / / no Comparative Example 11 / / / / no Comparative Example 12 23.04 8.71 3.6 rare no Comparative Example 13 22.9 8.84 3.52 often no
[0061] Comparative Examples 1-2 show that SMA springs were manufactured under cold-rolling conditions. During the manufacturing process, wire breakage frequently occurred, making spring forming difficult. Furthermore, the dimensions of springs of corresponding specifications were extremely unstable, requiring secondary mold shaping. Figure 3 As shown, the height of the SMA spring changes little with temperature, and its stroke characteristics do not meet the working requirements. Comparative Example 3 increases the wire feeding speed compared to Comparative Example 1; the results show that excessively high wire feeding speed leads to frequent wire breakage, making wire feeding and SMA spring forming impossible. Comparative Examples 4 and 5 investigate the effect of preheating time on SMA springs. The results show that insufficient preheating time results in inadequate preheating of the SMA alloy wire, leading to unstable dimensions in the resulting SMA spring. Excessive preheating, on the other hand, causes changes in the microstructure of the SMA alloy wire, increasing the phase transition temperature of the SMA spring and affecting its performance. Figure 4As shown; Comparative Examples 12-13 studied the effect of wire feeding speed on SMA springs. Based on the fact that the wire feeding length is stable, the wire feeding speed and the preheating time are inversely proportional. The preheating time is not considered here. The SMA spring produced by the wire feeding speed is comparable to the SMA spring produced in Example 4, and the SMA spring produced by the wire feeding speed is comparable to the SMA spring produced in Example 5. The results are consistent.
[0062] Comparative Examples 6 and 7 considered the effect of preheating length on the performance of the SMA springs. The results showed that if the preheating length was too short, the SMA alloy wire would not be preheated sufficiently and would not be heated enough, resulting in frequent wire breakage during preparation. This would lead to a large dimensional error in the SMA springs. On the other hand, if the preheating length was too long and the wire feeding speed was too slow, the heat loss of the heated wire would be severe, and the microstructure of the SMA alloy wire would also change, causing the phase transition temperature of the SMA spring to rise.
[0063] Comparative Examples 8 and 9, compared to Example 1, investigated the effect of changing the winding temperature of the SMA spring on its performance. The results showed that a winding temperature that is too low is equivalent to cold coiling; a winding temperature that is too high will affect the microstructure of the SMA alloy wire, such as... Figure 5 As shown, this leads to an increase in the phase transition temperature of the SMA spring, a weakening of its stroke characteristics, and the surface of the manufactured SMA spring is easily scratched. Furthermore, excessive compression of the SMA spring results in wire drawing. Comparative Examples 10 and 11, compared to Example 1, investigated the effect of the alloy wire diameter on the manufactured SMA spring. The results showed that alloy wires with a diameter less than 0.1 mm are prone to wire detachment under these process conditions, and the wires have high flexibility, which is detrimental to the dimensional stability of the formed SMA spring. Meanwhile, wire diameters exceeding 3.0 mm result in insufficient preheating under these processes, requiring modification of the device structure.
[0064] This invention discloses a short-process manufacturing method for SMA springs, employing a hot-winding method to directly wind and form the SMA spring at a winding temperature of Af+120℃~Af+240℃. Compared to existing technologies, the SMA springs produced by this invention exhibit dimensional stability after forming, eliminating the need for secondary mold-setting and heat treatment. This significantly improves the manufacturing efficiency of SMA springs, reduces production costs, and enables mass production. A thermostatic valve made using the SMA springs produced by this invention has been applied to a hot and cold water mixing control system in a bathroom. Results show that the thermostatic valve made using the SMA springs of this invention functions stably in the hot and cold water mixing control system, exhibiting not only high sensitivity but also a long service life.
[0065] While the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the invention. Those skilled in the art can make various modifications and refinements without departing from the spirit and scope of the invention. Therefore, the scope of protection of the present invention shall be determined by the claims.
Claims
1. A short-process manufacturing method for SMA springs, characterized in that, SMA springs are formed by hot rolling, wherein the hot rolling method involves winding SMA alloy wire into SMA springs at a winding forming temperature of Af+120℃~Af+240℃.
2. The short-process manufacturing method for SMA springs according to claim 1, characterized in that, The winding forming temperature is achieved as follows: An SMA spring winding equipment is constructed, comprising a fully automatic wire feeder, a tunnel-type heat preservation furnace, and a CNC universal spring machine arranged sequentially. The fully automatic wire feeder is used for automatic wire feeding, providing speed compensation for SMA alloy wire, and providing abnormal stop and alarm functions. The furnace chamber of the tunnel insulation furnace uses PID temperature control to preheat the mandrel of the CNC universal spring machine, so that the temperature of the SMA alloy wire conducted by the mandrel during the winding of the forming spring rises to Af+120℃~Af+240℃.
3. The short-process manufacturing method for SMA springs according to claim 1, characterized in that, The winding forming temperature is achieved as follows: An SMA spring winding equipment is constructed, comprising a constant temperature environment chamber and a spring compression machine installed inside the constant temperature environment chamber; The constant temperature environment chamber includes an outer shell made of cold-rolled steel plate, an insulation layer made of ceramic fiber disposed inside the outer shell, a heating element, and an Omron E5CC 850 digital temperature controller. The Omron E5CC 850 digital temperature controller controls the temperature inside the constant temperature environment chamber to the winding forming temperature of the SMA spring, Af+120℃~Af+240℃.
4. The short-process manufacturing method for SMA springs according to claim 1, characterized in that, The winding forming temperature is achieved as follows: An SMA spring winding equipment is constructed, which includes a CNC universal spring machine and a high-frequency induction coil. The high-frequency induction coil is located on the mandrel side near the CNC universal spring machine, and a heating space is formed inside the high-frequency induction coil. When the mandrel winds the spring, the CNC universal spring machine pre-feeds an SMA alloy wire of a set specification into the heating space. The SMA alloy wire is heated to Af+120℃~Af+240℃ in the heating space. After heating is completed, the wire feeding wheel of the CNC universal spring machine reverses and returns the heated SMA alloy wire to the spring winding processing area for processing.
5. The short-process manufacturing method for SMA springs according to claim 1, characterized in that, Includes the following steps: 1) After installing the SMA alloy wire spool on the spring machine; 2) Start the spring machine, feed the SMA alloy wire to the preheating zone for preheating, and then feed the preheated SMA alloy wire to the spring winding processing area; 3) SMA springs are produced by winding at a winding temperature of Af+120℃~Af+240℃ according to the preset length and shape.
6. The short-process manufacturing method for SMA springs according to claim 5, characterized in that, The diameter of the SMA alloy wire in the SMA alloy wire spool is 0.2 to 3.0 mm.
7. The short-process manufacturing method for SMA springs according to claim 5, characterized in that, The conveying speed of the SMA alloy wire is 12.5 to 125 mm / s.
8. The short-process manufacturing method for SMA springs according to claim 5, characterized in that, The SMA alloy wire is preheated in the preheating zone for 24–240 seconds, and the preheating length is 3–6 m.
9. The application of the SMA spring prepared by the short-process preparation method according to any one of claims 1-8 in a valve of a fluid control system.