A shape memory alloy MEMS safety system with dual functions of release and actuation

Abstract

The present invention discloses a shape memory alloy MEMS safety system with dual functions of release and drive, which is mainly composed of a recoil safety mechanism, a flameproof slider and a shape memory alloy actuator. The flameproof slider is designed with a recoil safety mechanism safety slot, a shape memory alloy actuator safety slot, a positioning slot and a drive slot, and the shape memory alloy actuator is divided into a safety mechanism and a drive mechanism. The recoil safety mechanism is snapped into the safety slot to realize the first safety of the flameproof slider, the shape memory alloy safety mechanism is snapped into the safety slot to realize the second safety of the flameproof slider, and the shape memory alloy drive mechanism is used to push the flameproof slider into place. The technical problem to be solved by the present invention is to achieve the goal of miniaturization of small-caliber ammunition and long-distance safe release of the safety, and has the following advantages: (1) small structural size; (2) strong overload resistance; (4) low cost; (5) simple principle and fast action speed; (6) good stability and reliable operation.

Description

Technical Field

[0001] The present invention relates to a shape memory alloy MEMS safety system with dual functions of disarming and driving, and in particular to a principle and a design method of a shape memory alloy MEMS safety system with dual functions of disarming and driving, belonging to the technical field of fuze MEMS safety systems. Background Art

[0002] The technology of the full electronic safety system of fuze is one of the core technologies in weapon systems that responds to high-tech the fastest and is most sensitive. With the continuous development and progress of weapon equipment technology, in order to meet the needs of modern actual combat environments, the function of fuzes is also constantly expanding. However, due to the limitations of the shape of ammunition and the size of the interface between the fuze and the ammunition warhead, it is difficult to change the shape of the fuze on a large scale. In order to save space and add more functional modules, it is necessary to further compress the volume of devices such as the fuze system and the detonation control system. However, traditional technologies can no longer meet the actual needs of reducing the volume of the fuze system. The miniaturization of the fuze size has become one of the key issues that need to be solved urgently.

[0003] Small-caliber ammunition generally refers to ammunition with a caliber of 20mm to 40mm, which is fired by artillery and achieves killing, blasting, penetration and other effects. Small-caliber ammunition is widely used in anti-aircraft guns, naval guns, aircraft guns and other land, sea and air forces and other combat force equipment due to its advantages such as strong mobility, fast firing speed and large carrying capacity. In order to improve the killing probability of small-caliber ammunition, it is required not only that the fuze is triggered when the ammunition directly hits the target, but also that the proximity fuze is required to play a role when the ammunition cannot directly hit. Radio fuzes and laser fuzes can effectively improve the damage probability of ammunition. However, intelligent control modules such as radio or laser usually have a large volume. At the same time, since the charge of small-caliber ammunition is greatly limited by the volume of the warhead, this greatly affects the damage efficiency of the ammunition. Therefore, miniaturization of the fuze size is of great significance for increasing the volume of the warhead and thus improving the damage efficiency of small-caliber ammunition. How to reduce the volume of the fuze safety system to expand the function of the fuze, realize the miniaturization and intelligence of the fuze and ensure the destructive effect of the warhead is an urgent problem to be solved in the current research on small-caliber ammunition fuzes.

[0004] MEMS technology can integrate the functions of sensing, signal processing, computing, control and execution, and has great application potential in the full electronic safety system of fuzes. MEMS technology provides a very important research direction and technical approach for the intelligence, miniaturization and multifunctionality of fuzes. The actuator based on MEMS technology has the characteristics of small size, light weight, full functions, strong overload resistance and low cost, which is very suitable for fuze safety systems. Applying MEMS technology to fuzes and realizing the miniaturization of fuze safety systems can meet the major demands of weapon systems for low cost, small size, multifunctionality and high reliability of small-caliber ammunition fuzes.

[0005] The requirement for the safety system to remotely release the safety is an important challenge faced by the application of MEMS technology to small-caliber ammunition fuzes. In order to ensure the safety of small-caliber ammunition firing, it is generally required that the safety be released after the projectile is ejected from the muzzle at a safe distance of more than 20 meters. The currently disclosed small-caliber ammunition fuze safety insurance mechanism basically uses the rotational centrifugal force or recoil overload excitation after the ammunition is fired to achieve release, but the firing environments of different types of small-caliber ammunition vary greatly, and the safety insurance mechanism that relies on environmental forces to achieve release has certain limitations. Most of the current MEMS safety systems are mechanical safety systems, and how to achieve the remote release function has always been a difficult point in the research of fuze MEMS safety systems.

[0006] The miniature safety and driving mechanisms based on new functional materials and structures such as magnetorheological materials, antiferroelectric ceramics, and shape memory alloys provide a new way for MEMS safety systems to achieve the remote release function. Among them, shape memory alloys refer to alloys with a certain initial shape that can be plastically deformed and fixed into another shape at low temperature, and then restored to the initial shape by heating above the critical temperature. As a special new functional material, shape memory alloys can integrate sensing and driving functions. The miniature driving mechanism based on shape memory alloy materials has the advantages of large output driving force and driving displacement, and has good application prospects in fuze trajectory correction and safety system release. The development of the preparation process of shape memory alloy materials based on silicon substrates makes it possible to integrate shape memory alloys with silicon-based MEMS devices, laying a solid foundation for the development of MEMS safety systems based on shape memory alloy driving mechanisms.

[0007] Shape memory alloys are very suitable for realizing the dual functions of driving and releasing the fuse MEMS safety system. By detecting environmental information through sensors and integrating them with shape memory alloy drive mechanisms, the function of remote release of the fuse is realized while improving the reliability of the action by adopting an electromechanical combination. The MEMS actuator designed based on the characteristics of shape memory alloys with strong driving force and large driving displacement can not only meet the military needs of miniaturization, generalization and high reliability of small-caliber ammunition fuses, but also promote the deep cross-integration of disciplines such as intelligent materials and structures, MEMS technology, and mechanical system dynamics in fuses, which has important scientific significance and military value. Summary of the invention

[0008] In view of the above problems, the present invention discloses a shape memory alloy MEMS safety system with dual functions of release and actuation. The technical problem to be solved is: based on the problem of long-distance safe release of small-caliber ammunition, the MEMS technology is cleverly introduced into the full electronic safety system of the fuze, and the advantages of the shape memory alloy such as strong driving force and large driving displacement are used to complete the dual functions of the fuze system release and actuation, so as to achieve the goal of long-distance safe release of small-caliber ammunition, so that the MEMS fuze safety system has the following advantages: (1) small structure size; (2) strong overload resistance; (3) the shape memory alloy has large driving force and long driving displacement, which can realize the dual functions of release and actuation; (4) low cost and simple working principle; (5) short response time and fast action speed; (6) good stability and reliable operation.

[0009] The objective of the present invention is achieved through the following technical solutions:

[0010] The present invention discloses a shape memory alloy MEMS safety system with dual functions of release and drive, which is mainly composed of a shape memory alloy actuator, a flameproof slider and a silicon-based recoil safety mechanism. The flameproof slider is designed with a recoil safety mechanism safety slot and a shape memory alloy actuator safety slot, a positioning slot and a driving slot. The recoil safety mechanism is the first safety of the flameproof slider, and the shape memory alloy actuator is the second safety of the flameproof slider and drives the flameproof slider to move in place to complete the release function.

[0011] Preferably, in the shape memory alloy MEMS safety system with dual functions of release and drive, the silicon-based recoil safety mechanism serves as the first line of safety for the explosion-proof slider. When the small-caliber ammunition is not fired, the recoil safety mechanism fixes the explosion-proof slider through the safety groove to achieve the first line of safety function; when the small-caliber ammunition is in the firing stage in the chamber, the silicon-based recoil safety mechanism withdraws from the safety groove under the action of the recoil environmental force and releases the first line of safety for the explosion-proof slider.

[0012] Preferably, the shape memory alloy MEMS safety system with dual functions of release and drive, wherein the shape memory alloy actuator is used as the second safety and driving force source of the explosion-proof slider, and the sequential logic of release and drive can be realized by reasonably designing the gap between the driving end of the shape memory alloy driving mechanism and the driving slot of the explosion-proof slider. When the small-caliber ammunition is not fired or is in the stage of firing in the chamber, the shape memory alloy safety mechanism completes the second fixation of the explosion-proof slider through the safety slot to achieve the second safety function: when the small-caliber ammunition is in the air launch stage, the geomagnetic field strength changes greatly from the chamber to the external environment. The shape memory alloy actuator can be powered by the magnetic resistance sensor and the control circuit, and the shape memory alloy safety mechanism is deformed and then withdraws from the safety slot of the explosion-proof slider, releasing the second safety of the explosion-proof slider. At the same time, the shape memory alloy driving mechanism pushes the explosion-proof slider to move into place through the driving slot, and finally the locking mechanism can complete the locking of the explosion-proof slider in the release state. When the explosion-proof slider moves into place, the shape memory alloy safety mechanism fixes the explosion-proof slider in position through the positioning slot to prevent it from resetting. Shape memory alloys have the advantages of large driving force and long driving displacement. They can not only be used to release the second safety of the explosion-proof slider, but also provide sufficient driving force to push the explosion-proof slider into place, thereby eliminating the explosion-proof slider's dependence on centrifugal environmental forces and improving the stability and reliability of the fuze MEMS safety system.

[0013] Preferably, in the shape memory alloy MEMS safety system with dual functions of release and drive, the safety and drive mechanism of the shape memory alloy actuator are the key factors to realize the dual functions of release and drive, and are mainly composed of a safety mechanism for releasing the second safety and a drive mechanism for driving the flameproof slider to move. The two ends of the shape memory alloy actuator are fixed ends, and when working, the external voltage is directly applied to this part. The middle of the shape memory alloy actuator is a spring beam. After power is turned on, the shape memory alloy undergoes a phase change caused by thermal expansion and then deforms to realize the movement of the actuator.

[0014] Preferably, in the shape memory alloy MEMS safety system with dual functions of release and drive, the integration of shape memory alloy and actuator is the most important processing step to realize the dual functions of release / drive. The present invention requires processing components such as explosion-proof slider, recoil safety mechanism, shape memory alloy actuator and locking mechanism on the same silicon substrate. The silicon-based preparation process of shape memory alloy actuator is the key to realizing the integration of MEMS safety system. The present invention adopts a method based on the combination of polyethylene thermal expansion and sputtering process to prepare shape memory alloy actuator, so as to realize the integration of shape memory alloy and silicon-based devices. It is planned to use SOI silicon wafer with a top silicon thickness of 50μm, an oxide layer of 2μm and a base silicon thickness of 500μm. The top silicon is used as a structural layer, the middle SiO2 layer is used as a sacrificial layer, and the bottom substrate is a supporting material. The thermal expansion coefficient of polyethylene is 67 times that of silicon. This thermal characteristic provides sufficient expansion for the shape memory alloy spring, so that the shape memory alloy spring can store the position of correct execution displacement.

[0015] Beneficial Effects

[0016] 1. Compared with the existing fuze safety system, the present invention discloses a shape memory alloy MEMS safety system with dual functions of release and drive, which is used in the full electronic safety system of the fuze. The safety mechanism, drive mechanism and explosion-proof slider are integrated into the same silicon chip. It has the characteristics of small size, strong overload resistance, low cost and reliable operation. It can not only realize the miniaturization of the fuze safety system, but also meet the performance requirements of the weapon system for small-caliber ammunition fuzes in terms of low cost, small size, multi-function and high reliability.

[0017] 2. The present invention discloses a shape memory alloy MEMS safety system with dual functions of release and drive. Different from the traditional fuze safety system, the explosion-proof slider, recoil safety mechanism, safety mechanism, drive mechanism and locking mechanism are processed on the same silicon substrate using silicon-based materials. Silicon materials have the advantages of abundant sources, low production costs and strong overload resistance. The current silicon-based preparation process is also relatively mature. Therefore, using silicon materials to prepare a drive safety system is an economical and feasible solution.

[0018] 3. The present invention discloses a shape memory alloy MEMS safety system with dual functions of release and drive. Different from the traditional fuze safety system, the safety and drive mechanism based on shape memory alloy is the most important component to realize the dual functions of release and drive. Shape memory alloy has the advantages of strong driving force and large driving displacement. It can be used to release the second safety of the explosion-proof slider, and can also drive the explosion-proof slider to move into place to complete the release action. The present invention adopts a method based on the combination of polyethylene thermal expansion and sputtering process to prepare shape memory alloy actuators, and realizes the integration of shape memory alloys and silicon-based devices. The driving mechanism of the shape memory alloy actuator can eliminate the dependence of the explosion-proof slider on the environmental centrifugal force, improve the stability and reliability of the fuze release driver, and meet the performance requirements of the weapon system for small-caliber ammunition fuzes in terms of low cost, small size, multi-function and high reliability.

[0019] 4. The present invention discloses a shape memory alloy MEMS safety system with dual functions of release and drive. On the basis of fully considering the actual application background of small-caliber ammunition fuze, a shape memory alloy actuator is used as the second safety mechanism and driving mechanism of the fuze MEMS safety system. The explosion-proof slider is designed with a recoil safety mechanism safety groove to realize the first safety of the explosion-proof slider, and a shape memory alloy actuator safety groove, positioning groove and driving groove are designed to realize the second safety of the explosion-proof slider and serve as a driving force to push the explosion-proof slider to move into place to complete the release state. When the small-caliber ammunition is not fired, the recoil safety mechanism completes the fixation of the explosion-proof slider through the safety groove to achieve the first safety function; when the small-caliber ammunition is in the in-bore firing stage, the silicon-based recoil safety mechanism withdraws from the safety groove under the action of the recoil environmental force and releases the first safety of the explosion-proof slider. The shape memory alloy safety mechanism completes the second fixation of the explosion-proof slider through the safety groove, thereby achieving the second safety function: when the small-caliber ammunition is in the air launch stage, the geomagnetic field strength changes greatly from the inside of the chamber to the external environment. The shape memory alloy actuator can be powered through the magnetoresistive sensor and the control circuit, and the shape memory alloy safety mechanism is deformed and then withdraws from the safety groove of the explosion-proof slider, releasing the second safety of the explosion-proof slider. At the same time, the shape memory alloy driving mechanism pushes the explosion-proof slider into place through the driving groove, and finally the locking mechanism can complete the locking of the explosion-proof slider in the released state, which meets the performance requirements of the fuze MEMS safety system such as good stability, strong safety and reliable operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The present invention discloses a shape memory alloy MEMS safety system with dual functions of release and drive.

[0021] Figure 2The present invention discloses a structural schematic diagram of a recoil safety mechanism in a shape memory alloy MEMS safety system having dual functions of release and drive.

[0022] Figure 3 The present invention discloses a flameproof slider structure in a shape memory alloy MEMS safety system with dual functions of release and drive.

[0023] Figure 4 The present invention discloses a shape memory alloy actuator structure schematic diagram in a shape memory alloy MEMS safety system with dual functions of release and drive.

[0024] Among them: 1—recoil safety mechanism, 2—explosion-proof slider, 3—shape memory alloy actuator; 2-1—recoil safety mechanism safety slot, 2-2—shape memory alloy safety mechanism safety slot, 2-3—shape memory alloy safety mechanism positioning slot, 2-4—shape memory alloy driving mechanism driving slot; 3-1—shape memory alloy safety mechanism, 3-2—shape memory alloy driving mechanism. DETAILED DESCRIPTION

[0025] In order to better illustrate the purpose and advantages of the present invention, the invention is further described below in conjunction with the accompanying drawings and embodiments.

[0026] Embodiment 1:

[0027] This embodiment discloses a shape memory alloy MEMS security system with dual functions of release and actuation. Figure 1 As shown. It is mainly composed of a silicon-based recoil safety mechanism 1, a flameproof slider 2 and a shape memory alloy actuator 3. The flameproof slider is designed with a recoil safety mechanism safety groove 2-1, a shape memory alloy safety mechanism safety groove 2-2, a shape memory alloy safety mechanism positioning groove 2-3 and a shape memory alloy driving mechanism driving groove 2-4. The shape memory alloy actuator is divided into a safety mechanism 3-1 and a driving mechanism 3-2; wherein, the recoil safety mechanism 1 is fixed to the flameproof slider 2 through the recoil safety mechanism safety groove 2-1 to achieve the first safety function. The shape memory alloy safety mechanism 3-1 is fixed to the flameproof slider 2 through the shape memory alloy safety mechanism safety groove 2-2 to achieve the second safety function. The shape memory alloy driving mechanism 3-2 matches the driving groove 2-4 to push the flameproof slider 2 to move in place to achieve the purpose of releasing the protection. The shape memory alloy safety mechanism 3-1 can be fixed in position with the flameproof slider 2 through the positioning groove 2-3 to prevent it from resetting. The invention discloses a shape memory alloy MEMS safety system with dual functions of release and drive, which has the advantages of small structure size, strong overload resistance, simple principle, good stability and reliable operation.

[0028] Figure 1In the embodiment shown, the flameproof slider 2, the recoil safety mechanism 1, the shape memory alloy actuator 3 and other structures need to be processed on the same silicon substrate. The recoil safety mechanism 1 and the flameproof slider 2 are respectively as shown in FIG. Figure 2 and Figure 3 As shown, when the small-caliber ammunition is in the stage of firing in the bore, the silicon-based recoil safety mechanism 1 withdraws from the safety slot 2-1 under the action of the recoil environment force, and releases the first safety of the explosion-proof slider 2; when the small-caliber ammunition is in the stage of air firing, the geomagnetic field strength changes greatly from the bore to the external environment, and the shape memory alloy actuator 3 can be powered by the magnetic resistance sensor and the control circuit, and the shape memory alloy safety mechanism 3-1 is deformed and then withdraws from the safety slot 2-2, releasing the second safety of the explosion-proof slider 2. At the same time, the shape memory alloy driving mechanism 3-2 pushes the explosion-proof slider 2 to move into place through the driving slot 2-4, and finally the locking mechanism can complete the locking of the explosion-proof slider in the released state. When the explosion-proof slider 2 moves into place, the shape memory alloy safety mechanism 3-1 can fix the explosion-proof slider 2 in position through the positioning slot 2-3 to prevent it from resetting.

[0029] Example 2

[0030] Figure 1 In the embodiment shown, the shape memory alloy actuator 3 is as shown in FIG. Figure 4 As shown, it is composed of a shape memory alloy safety mechanism 3-1 and a shape memory alloy driving mechanism 3-2, respectively, and is processed and prepared by an integrated method. The integration of shape memory alloy and actuator is the most important processing step to realize the dual functions of release / drive, and the silicon-based preparation process of shape memory alloy actuator 3 is the key to realize the integration of MEMS safety system. The present invention adopts a method based on the combination of polyethylene thermal expansion and sputtering process to prepare shape memory alloy actuator 3, so as to realize the integration of shape memory alloy and silicon-based devices. It is planned to use SOI silicon wafers with a top silicon thickness of 50μm, an oxide layer of 2μm, and a base silicon thickness of 500μm. The top silicon is used as a structural layer, the middle SiO2 layer is used as a sacrificial layer, and the bottom substrate is a supporting material. The thermal expansion coefficient of polyethylene is 67 times that of silicon. This thermal characteristic provides sufficient expansion for the shape memory alloy spring, so that the shape memory alloy spring can store the correct position of the displacement. Shape memory alloy has the advantages of large driving force and long driving displacement. It can not only be used to release the second insurance of the flameproof slider 2, but also provide sufficient driving force to push the flameproof slider 2 into place, thereby eliminating the dependence of the flameproof slider 2 on the centrifugal environmental force and improving the stability and reliability of the fuze MEMS safety system. The specific process flow of preparing the shape memory alloy actuator 3 is as follows:

[0031] 1. Using a 1μm thick SiO2 layer as the outer protective layer, the structural layer is etched using deep reactive ion etching (DRIE) technology. Then the polyethylene filler is deposited using laser evaporation;

[0032] 2. First, DRIE is used to etch the structural layer, and a 1 μm thick SiO2 layer is used as an outer protective layer. Then, a TiNi-shape memory alloy layer is deposited by sputtering;

[0033] 3. Using SiO2 as a protective layer, DRIE etching is performed on the polyethylene, TiNi and silicon material areas in the structural layer to etch out a complete motion structure;

[0034] 4. After etching the corresponding area on the back of the SOI silicon wafer, the SiO2 layer in the SOI silicon wafer is released so that part of the structure that needs to be deformed is suspended in the air, and the overall structure processing is completed.

[0035] (1) The method for realizing the spring memory position of the silicon-based shape memory alloy (TiNi) actuator is as follows:

[0036] (2) heating the entire substrate to 110° C. to expand the polyethylene, thereby driving the shape memory alloy and the silicon structure to reach a preset displacement, i.e., the working displacement of the shape memory alloy actuator;

[0037] (3) using dry oxidation to deposit a SiO2 layer on top of the entire substrate, maintaining the layout of the entire structure;

[0038] (4) Use DRIE to remove polyethylene blocks;

[0039] (5) heating the entire substrate to a phase transition temperature to complete the position memory of the shape memory alloy;

[0040] (6) Remove the SiO2 on the top that maintains the structure, and chemically vapor deposit a metal layer to lead out the control wires.

[0041] Finally, it should be noted that the specific description described above further illustrates the purpose, technical solutions and beneficial effects of the invention in detail, with the aim of helping to further understand the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A shape memory alloy MEMS safety system with dual functions of release and actuation, comprising a recoil safety mechanism (1), an explosion-proof slider (2) and a shape memory alloy actuator (3), characterized in that: The flameproof slider (2) is provided with a recoil safety mechanism safety slot (2-1), a shape memory alloy safety mechanism safety slot (2-2), a shape memory alloy safety mechanism positioning slot (2-3) and a shape memory alloy driving mechanism driving slot (2-4); the shape memory alloy actuator (3) is composed of a shape memory alloy safety mechanism (3-1) for releasing the second safety and a shape memory alloy driving mechanism (3-2) for driving the flameproof slider (2) to move. Both ends of the shape memory alloy actuator (3) are fixed ends. When working, an external voltage is directly applied to these parts. The middle of the shape memory alloy actuator (3) is a spring beam. After power is applied, the shape memory alloy undergoes phase change caused by thermal expansion and then deforms, thereby realizing the deformation and movement of the shape memory alloy safety mechanism (3-1) and the shape memory alloy driving mechanism (3-2); the recoil safety mechanism (1 ) and a shape memory alloy safety mechanism (3-1) realize the insurance of the explosion-proof slider (2) through a recoil safety mechanism safety groove (2-1) and a shape memory alloy safety mechanism safety groove (2-2); the shape memory alloy driving mechanism (3-2) pushes the explosion-proof slider to move into place and releases the insurance by matching with the shape memory alloy driving mechanism driving groove (2-4); the shape memory alloy MEMS safety system needs to process the recoil safety mechanism (1), the explosion-proof slider (2), the shape memory alloy actuator (3) and the locking mechanism on the same silicon substrate, and the silicon-based device is prepared by SOI silicon wafer, the top silicon is used as the structural layer, the middle SiO2 layer is used as the sacrificial layer, and the bottom substrate is the substrate layer; the shape memory alloy actuator (3) is prepared by combining the polyethylene thermal expansion and sputtering process to realize the integration of shape memory alloy and silicon-based devices.

2. A shape memory alloy MEMS security system with dual functions of release and actuation as claimed in claim 1, characterized in that: The recoil safety mechanism (1) serves as the first safety of the flameproof slider (2). When the small-caliber ammunition is not fired, the recoil safety mechanism (1) fixes the position of the flameproof slider (2) through the recoil safety mechanism safety groove (2-1), thereby completing the first safety. When the small-caliber ammunition is in the firing stage in the chamber, the recoil safety mechanism (1) withdraws from the recoil safety mechanism safety groove (2-1) under the action of the recoil environmental force, thereby releasing the first safety of the flameproof slider (2).

3. A shape memory alloy MEMS security system with dual functions of release and actuation as claimed in claim 1, characterized in that: The shape memory alloy actuator (3) serves as a second safety and driving force source, and the sequential logic of release and driving can be realized by designing the gap between the driving end of the shape memory alloy driving mechanism (3-2) and the driving slot (2-4) of the shape memory alloy driving mechanism; when the small-caliber ammunition is not fired or is in the in-bore firing stage, the shape memory alloy safety mechanism (3-1) fixes the position of the explosion-proof slider (2) through the shape memory alloy safety mechanism safety slot (2-2), thereby completing the second safety; when the small-caliber ammunition is in the air firing stage, the geomagnetic field intensity changes greatly from the in-bore to the external environment, and the shape memory alloy actuator (3) is powered by the magnetoresistive sensor and the control circuit, and the shape memory alloy safety mechanism (3-1) is deformed to exit the shape memory. The shape memory alloy safety mechanism safety groove (2-2) releases the second safety of the flameproof slider (2); the shape memory alloy driving mechanism (3-2) pushes the flameproof slider (2) to move into place through the shape memory alloy driving mechanism driving groove (2-4); and finally the flameproof slider (2) is locked in the released state through the locking mechanism. When the flameproof slider (2) moves into place, the shape memory alloy safety mechanism (3-1) can limit the flameproof slider (2) through the shape memory alloy safety mechanism positioning groove (2-3) to prevent the flameproof slider from resetting. The shape memory alloy actuator (3) is not only used to release the second safety of the flameproof slider (2), but also provides driving force to push the flameproof slider (2) to move into place, thereby eliminating the flameproof slider (2) from relying on the centrifugal environmental force.

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