A honeycomb sandwich sheet metal lightweight structure
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-29
- Publication Date
- 2026-08-14
AI Technical Summary
[0003]现有蜂窝夹层结构多采用胶粘剂将蜂窝芯与面板永久粘接，这种固定方式虽然能够保证结构强度，但一旦安装完成便难以拆卸，导致维修更换成本高昂，材料回收利用率低，特别是在需要频繁检修或局部更换的应用场景中，如建筑幕墙、车辆内饰、设备外壳等，传统胶接方式严重制约了结构的使用灵活性和经济性
[0016]与现有技术相比，本实用新型提供了一种蜂窝夹层式钣金轻量化结构，具备以下有益效果：
Smart Images
Figure CN224635223U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of sheet metal technology, specifically a honeycomb sandwich sheet metal lightweight structure. Background Technology
[0002] Honeycomb sandwich sheet metal lightweight structure is a composite structure formed by sandwiching a lightweight core material between two thin skin layers. It features high strength, high rigidity, and light weight. The structure is made of two layers of sheet metal panels and a lightweight core material bonded together with an adhesive. The core material is usually made of materials such as honeycomb cardboard, corrugated cardboard, aluminum plate, or plastic plate, while the panel material is mostly aluminum alloy, fiberglass composite material, etc. Through the synergistic effect of the panel and core material, the bending strength and torsional stiffness are significantly improved, supporting complex shape designs such as bending and irregular structures. It also has a short production cycle and is suitable for large-scale automated production. It is mainly used in automotive exterior parts such as spare tire covers, sunroof visors, body structural parts, as well as civil aircraft wings and bulkheads, which are sensitive to strength and weight.
[0003] Existing honeycomb sandwich structures mostly use adhesives to permanently bond the honeycomb core to the panels. While this fixing method ensures structural strength, it is difficult to disassemble once installed, leading to high maintenance and replacement costs and low material recycling rates. This is especially problematic in applications requiring frequent maintenance or partial replacement, such as building curtain walls, vehicle interiors, and equipment housings, where traditional adhesive bonding severely restricts the flexibility and economy of the structure. Furthermore, the connection between adjacent honeycomb panels in traditional honeycomb sandwich structures typically relies on complex mechanical fasteners or secondary adhesive bonding processes, increasing assembly complexity and affecting the overall structural flatness and aesthetics. Utility Model Content
[0004] (a) Technical problems to be solved
[0005] To address the shortcomings of existing technologies, this utility model provides a honeycomb sandwich sheet metal lightweight structure, which solves the problems mentioned in the background.
[0006] (II) Technical Solution
[0007] To achieve the above objectives, this utility model provides the following technical solution: a honeycomb sandwich sheet metal lightweight structure, including a panel and a core plate, wherein the core plate is located between two sets of panels, the panel is provided with an installation mechanism for installing the core plate, and a connecting mechanism is provided between two adjacent sets of core plates;
[0008] The core board is movably engaged with the corresponding panel. The mounting mechanism includes two sets of first slides slidably installed inside the panel. Both sets of first slides are movably engaged with the core board. A first rack is fixedly installed on each set of first slides. A first gear is provided between the two sets of first racks. The first gear meshes with the two sets of first racks respectively. The first gear is rotatably connected to the panel through a handle. The two sets of first slides are centrally symmetrically distributed about the handle. A first torsion spring is sleeved on the handle. The two ends of the first torsion spring are fixedly connected to the first gear and the panel respectively. A first slide rod corresponding to the first slide is fixedly installed inside the panel. The first slide is slidably engaged with the corresponding first slide rod. Two sets of symmetrically distributed first springs are sleeved on the first slide rod. The two ends of the two sets of first springs are fixedly connected to the first slide and the panel respectively. The connecting mechanism includes a connecting block fixedly installed on the right core board. The right core board is movably engaged with the left core board through the connecting block.
[0009] Preferably, the handle is fitted with two sets of symmetrically distributed ratchet wheels, and the panel is provided with two sets of pawls corresponding to the ratchet wheels. The two sets of pawls are respectively engaged with the corresponding ratchet wheels. Both sets of pawls are rotatably connected to the panel through rotating rods. A second torsion spring is fitted on each of the two sets of rotating rods, and the two ends of the second torsion spring are respectively fixedly connected to the pawl and the panel. A third gear is fitted on the lower end of each of the two sets of rotating rods. Two sets of third racks that are engaged with the third gears are slidably installed in the panel.
[0010] Preferably, a connecting frame is slidably installed inside the panel, and the connecting frame is fixedly connected to two sets of third racks respectively. A third slide rod corresponding to the connecting frame is fixedly installed inside the panel. The connecting frame is slidably sleeved with the corresponding third slide rod, and two sets of symmetrically distributed third springs are sleeved on the third slide rod. The two ends of the two sets of third springs are fixedly connected to the connecting frame and the panel respectively. A locking block is fixedly installed on the connecting frame.
[0011] Preferably, a locking rod corresponding to the locking block is fixedly installed inside the panel. Two sets of symmetrically distributed locking brackets are sleeved on the locking rod. The two sets of locking brackets are movably locked with the locking block. A third torsion spring is sleeved on the locking rod. The two ends of the third torsion spring are fixedly connected to the corresponding locking bracket and the locking rod, respectively.
[0012] Preferably, the connecting mechanism further includes two sets of second slides slidably installed in the left core plate. The two sets of second slides can be movably engaged with the connecting block. A second rack is fixedly installed on each of the two sets of second slides. A second gear is provided between the two sets of second racks. The second gear meshes with the two sets of second racks respectively. The second gear is rotatably connected to the core plate through the mounting shaft. The two sets of second slides are centrally symmetrical about the mounting shaft. A tie rod is rotatably installed in the core plate and is perpendicular to the mounting shaft. Two sets of second slide rods corresponding to the second slides are fixedly installed in the core plate.
[0013] Preferably, a fourth torsion spring is sleeved on both the mounting shaft and the pull rod. The two ends of the fourth torsion spring are respectively fixedly connected to the corresponding mounting shaft or pull rod and the core plate. A first bevel gear is sleeved on the mounting shaft, and a second bevel gear is sleeved on the pull rod, with the second bevel gear meshing with the first bevel gear.
[0014] Preferably, the second slide is slidably sleeved with the corresponding second slide rod, and two sets of symmetrically distributed second springs are sleeved on the second slide rod. The two ends of the two sets of second springs are respectively fixedly connected to the second slide and the core plate.
[0015] (III) Beneficial Effects
[0016] Compared with the prior art, this utility model provides a honeycomb sandwich sheet metal lightweight structure, which has the following beneficial effects:
[0017] When the pawl engages with the ratchet, the handle position is automatically locked, ensuring structural stability. For adjustments, simply pull the connecting bracket; the third rack and third gear drive the two sets of pawls to disengage from the ratchet, thus unlocking the handle. The unlocked handle then drives the first gear to rotate. Through the synchronous reverse movement of the two sets of first racks, the extension and retraction of the first carriage are precisely controlled, achieving elastic engagement or disengagement of the panel and core plate. This integrates unlocking, transmission, and engagement functions, allowing for convenient switching between locked and unlocked states. This ensures the reliability of the structural connection and significantly improves assembly and disassembly efficiency. Simultaneously, the built-in torsion spring and spring system provides elastic compensation for each moving part, ensuring fitting accuracy during long-term use. Compared to traditional adhesive bonding, this structure not only achieves non-destructive assembly and disassembly and component replacement, but its unique mechanical interlocking design also effectively prevents accidental loosening. It is particularly suitable for lightweight structural applications requiring frequent maintenance in fields such as construction and transportation. Attached Figure Description
[0018] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments of this application and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:
[0019] Figure 1 This is a schematic diagram of the overall structure of this utility model;
[0020] Figure 2 This is a schematic diagram of a partially disassembled structure of the present invention;
[0021] Figure 3 This is a schematic diagram of the installation mechanism of this utility model;
[0022] Figure 4 This is a schematic diagram of the ratchet and pawl structure of this utility model;
[0023] Figure 5This is a schematic diagram of the connection mechanism of this utility model.
[0024] In the diagram: 1. Panel; 2. Core board; 3. Mounting mechanism; 301. First slide; 302. First rack; 303. First gear; 304. Handle; 305. First torsion spring; 306. First slide rod; 307. First spring; 308. Ratchet; 309. Pad; 310. Rotating rod; 311. Second torsion spring; 312. Third gear; 313. Third rack; 314. Connecting frame; 315. Third slide rod 316. Rod; 317. Third spring; 318. Locking block; 319. Locking rod; 320. Locking bracket; 4. Connecting mechanism; 401. Connecting block; 402. Second slide; 403. Second rack; 404. Second gear; 405. Mounting shaft; 406. Fourth torsion spring; 407. Pull rod; 408. First bevel gear; 409. Second bevel gear; 410. Second slide rod; 411. Second spring. Detailed Implementation
[0025] The following will describe in detail the implementation of this application with reference to the accompanying drawings and embodiments, so that the implementation process of how this application uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.
[0026] Figures 1-5In one embodiment of this utility model, a honeycomb sandwich sheet metal lightweight structure includes a panel 1 and a core plate 2. The core plate 2 is located between two sets of panels 1. A mounting mechanism 3 for mounting the core plate 2 is provided within the panel 1, and a connecting mechanism 4 is provided between adjacent sets of core plates 2. The core plate 2 is movably engaged with the corresponding panel 1. The mounting mechanism 3 includes two sets of first slides 301 slidably mounted within the panel 1. Both sets of first slides 301 are movably engaged with the core plate 2. A first rack 302 is fixedly mounted on each set of first slides 301. A first gear 303 is provided between the two sets of first racks 302, and the first gear 303 engages with the two core plates 2 respectively. The first rack 302 is engaged with the first gear 303, which is rotatably connected to the panel 1 via the handle 304. Two sets of first slides 301 are centrally symmetrically distributed about the handle 304. A first torsion spring 305 is sleeved on the handle 304, with both ends of the first torsion spring 305 fixedly connected to the first gear 303 and the panel 1, respectively. A first slide rod 306 corresponding to the first slide 301 is fixedly installed inside the panel 1. The first slide 301 and the corresponding first slide rod 306 are slidably sleeved. Two sets of symmetrically distributed first springs 307 are sleeved on the first slide rod 306, with both ends of the two sets of first springs 307 connected to the first slide 301. 01 and panel 1 are fixedly connected. The connecting mechanism 4 includes a connecting block 401 fixedly installed on the right core plate 2. The right core plate 2 is movably engaged with the left core plate 2 through the connecting block 401. When the pawl 309 engages with the ratchet 308, the handle 304 is automatically locked to ensure structural stability. When adjustment is needed, simply pull the connecting bracket 314 to drive the two sets of pawls 309 to disengage from the ratchet 308 through the transmission of the third rack 313 and the third gear 312, thereby releasing the handle 304 from locking. The unlocked handle 304 can drive the first gear 303 to rotate, and through the synchronous reverse movement of the two sets of first racks 302... The system precisely controls the extension and retraction of the first carriage 301, enabling the elastic engagement or disengagement of the panel 1 and the core plate 2. It integrates unlocking, transmission, and engagement functions into one unit, allowing for convenient switching between locked states during operation. This ensures the reliability of the structural connection and significantly improves disassembly and assembly efficiency. Meanwhile, the built-in torsion spring and spring system provides elastic compensation for each moving part, ensuring the fitting accuracy during long-term use. Compared with traditional adhesive processes, this structure not only achieves non-destructive disassembly and assembly and component replacement, but its unique mechanical interlocking design also effectively prevents accidental loosening. It is particularly suitable for lightweight structural applications in fields such as construction and transportation that require frequent maintenance.
[0027] In this embodiment, reference Figure 2 , Figure 3 , Figure 4As shown, two sets of symmetrically distributed ratchet wheels 308 are sleeved on the handle 304. The panel 1 has two sets of pawls 309 corresponding to the ratchet wheels 308. The two sets of pawls 309 are respectively engaged with the corresponding ratchet wheels 308. Both sets of pawls 309 are rotatably connected to the panel 1 via rotating rods 310. A second torsion spring 311 is sleeved on each of the two rotating rods 310, and both ends of the second torsion spring 311 are fixedly connected to the pawls 309 and the panel 1, respectively. A third gear 312 is sleeved on the lower end of each of the two rotating rods 310. Two sets of third racks 313 are slidably installed in the panel 1, engaging with the third gears 312. A connecting frame 314 is slidably installed in the panel 1, and the connecting frame 314 is fixedly connected to both sets of third racks 313. A third slide rod 315 corresponding to the connecting frame 314 is fixedly installed in the panel 1, and the connecting frame 314 and the corresponding third slide rod 315 are slidably sleeved. Furthermore, two sets of symmetrically distributed third springs 316 are sleeved on the third slide rod 315. The two ends of the two sets of third springs 316 are fixedly connected to the connecting frame 314 and the panel 1, respectively. A locking block 317 is fixedly installed on the connecting frame 314. A locking rod 318 corresponding to the locking block 317 is fixedly installed inside the panel 1. Two sets of symmetrically distributed locking brackets 319 are sleeved on the locking rod 318. The two sets of locking brackets 319 are movably locked with the locking block 317. A third torsion spring 320 is sleeved on the locking rod 318. The two ends of the third torsion spring 320 are fixedly connected to the corresponding locking bracket 319 and the locking rod 318, respectively, driving the first gear 303 to rotate synchronously. The first gear 303 meshes with the first racks 302 on both sides, driving the two sets of first slides 301 to slide synchronously inward along the first slide rod 306. During the movement, the first slides 301 cooperate with the locking grooves on the edge of the core plate 2 to achieve the clamping and fixing of the core plate 2. The first torsion spring 305 and the first spring 307 provide a reset force to ensure the stability of the snap-fit and the automatic centering function. When disassembly is required, the first slide 301 can be disengaged from the slot by rotating the handle 304 in the opposite direction, realizing the quick release of the core plate 2. After the connection between the panel 1 and the core plate 2 is completed, in order to ensure operational safety, the ratchet 308 and pawl 309 mechanism locks the handle 304 in both directions: when the pawl 309 is engaged with the ratchet 308, the handle 304 cannot rotate freely to prevent accidental loosening. When adjustment is required, the third rack 313 is moved by pulling the connecting bracket 314. The third rack 313 drives the third gear 312 to rotate, so that the pawl 309 disengages from the ratchet 308 and the locked state is released. At this time, the handle 304 can be rotated freely for disassembly and assembly operations.
[0028] In this embodiment, reference Figure 5As shown, the connecting mechanism 4 also includes two sets of second slides 402 slidably installed in the left core plate 2. The two sets of second slides 402 can be movably engaged with the connecting block 401. A second rack 403 is fixedly installed on each of the two sets of second slides 402. A second gear 404 is provided between the two sets of second racks 403. The second gear 404 meshes with the two sets of second racks 403 respectively. The second gear 404 is rotatably connected to the core plate 2 through the mounting shaft 405. The two sets of second slides 402 are centrally symmetrically distributed about the mounting shaft 405. The core plate 2 is rotatably installed with the connecting block 401. A tie rod 407 is vertically distributed on the shaft 405. Two sets of second slide rods 410, corresponding to the second slide 402, are fixedly installed inside the core plate 2. A fourth torsion spring 406 is sleeved on both the shaft 405 and the tie rod 407. The two ends of the fourth torsion spring 406 are fixedly connected to the corresponding shaft 405 or tie rod 407 and the core plate 2, respectively. A first bevel gear 408 is sleeved on the shaft 405, and a second bevel gear 409 is sleeved on the tie rod 407, with the second bevel gear 409 meshing with the first bevel gear 408. The second slide 402 and the corresponding second slide rod 410... The second slide rod 410 is fitted with two symmetrically distributed second springs 411. The two ends of the two sets of second springs 411 are fixedly connected to the second slide 402 and the core plate 2, respectively. The two sets of core plates 2 adopt a modular plug-in design for quick assembly. After the connecting block 401 of the right core plate 2 is inserted into the corresponding slot of the left core plate 2, the internal connecting mechanism 4 automatically locks. Under the action of the second springs 411, the second slide 402 tightens inward, clamping and fixing the connecting block 401 to ensure a stable connection. Simultaneously, the second gear 404 and the second rack 403... The meshing transmission enables the two sets of second slides 402 to move synchronously, ensuring uniform force distribution. If disassembly is required, simply rotate the pull rod 407, and in conjunction with the first bevel gear 408 and the second bevel gear 409, drive the mounting shaft 405 to rotate, causing the second gear 404 to drive the two sets of second racks 403 to move outward. The two sets of second slides 402 then release the connecting block 401, thus separating the core plate 2. This assembly method requires no additional fasteners, ensuring connection strength and improving assembly efficiency. It is suitable for modular assembly of large-size honeycomb sandwich structures, facilitating transportation, maintenance, and partial replacement.
[0029] In this embodiment, when the handle 304 is rotated, the first gear 303 is driven to rotate synchronously. The first gear 303 meshes with the first racks 302 on both sides, driving the two sets of first slides 301 to slide synchronously inward along the first slide rod 306. During the movement, the first slide 301 cooperates with the slot on the edge of the core plate 2 to achieve the clamping and fixing of the core plate 2. The first torsion spring 305 and the first spring 307 provide a reset force to ensure the stability of the snap-fit and the automatic centering function. When disassembly is required, rotating the handle 304 in the reverse direction will cause the first slide 301 to exit the slot, realizing the quick release of the core plate 2. After the connection between the panel 1 and the core plate 2 is completed, to ensure operational safety, the ratchet 308 and pawl 309 mechanism provides bidirectional locking to the handle 304: when the pawl 309 is engaged with the ratchet 308, the handle 304 cannot rotate freely to prevent accidental loosening. When adjustment is required, the connecting bracket 314 is pulled to move the third rack 313, which drives the third gear 312 to rotate, causing the pawl 309 to disengage from the ratchet 308 and release the locking state. At this time, the handle 304 can be rotated freely for disassembly and assembly operations. The two sets of core plates 2 adopt a modular plug-in design to achieve quick assembly. The right core plate 2 After the connecting block 401 is inserted into the corresponding slot of the left core plate 2, the internal connecting mechanism 4 automatically locks. The second slide 402 tightens inward under the action of the second spring 411, clamping and fixing the connecting block 401 to ensure a stable connection. At the same time, the meshing transmission of the second gear 404 and the second rack 403 makes the two sets of second slides 402 move synchronously, ensuring uniform force. If disassembly is required, simply rotate the pull rod 407, and cooperate with the first bevel gear 408 and the second bevel gear 409 to drive the mounting shaft 405 to rotate, so that the second gear 404 drives the two sets of second racks 403 to move outward. The two sets of second slides 402 release the connecting block 401, and the core plate 2 can be separated. This assembly method does not require additional fasteners, which not only ensures the connection strength but also improves the assembly efficiency. It is suitable for the modular assembly of large-size honeycomb sandwich structures and is convenient for transportation, maintenance and partial replacement.
[0030] The control method of this utility model is automatic control through a controller. The control circuit of the controller can be implemented by simple programming by those skilled in the art. The power supply is also common knowledge in the field. Since this utility model is mainly used to protect mechanical devices, the control method and circuit connection will not be explained in detail.
[0031] It should be noted that the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.
[0032] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A honeycomb sandwich sheet metal lightweight structure, comprising a panel (1) and a core panel (2), characterized in that: The core board (2) is located between two sets of panels (1). The panel (1) is provided with an installation mechanism (3) for installing the core board (2), and a connecting mechanism (4) is provided between two adjacent sets of core boards (2). The core plate (2) is movably engaged with the corresponding panel (1). The mounting mechanism (3) includes two sets of first slides (301) slidably mounted inside the panel (1). Both sets of first slides (301) are movably engaged with the core plate (2). A first rack (302) is fixedly mounted on each set of first slides (301). A first gear (303) is provided between the two sets of first racks (302). The first gear (303) meshes with the two sets of first racks (302) respectively. The first gear (303) is rotatably connected to the panel (1) through the handle (304). The two sets of first slides (301) are centrally symmetrically distributed about the handle (304). A first torsion spring (304) is sleeved on the handle (304). 5) The two ends of the first torsion spring (305) are fixedly connected to the first gear (303) and the panel (1) respectively. The panel (1) is fixedly installed with a first slide rod (306) corresponding to the first slide (301). The first slide (301) and the corresponding first slide rod (306) are slidably connected. Two sets of symmetrically distributed first springs (307) are sleeved on the first slide rod (306). The two ends of the two sets of first springs (307) are fixedly connected to the first slide (301) and the panel (1) respectively. The connecting mechanism (4) includes a connecting block (401) fixedly installed on the right core plate (2). The right core plate (2) is movably connected to the left core plate (2) through the connecting block (401).
2. The honeycomb sandwich sheet metal lightweight structure according to claim 1, characterized in that: Two sets of symmetrically distributed ratchet wheels (308) are sleeved on the handle (304). Two sets of pawls (309) corresponding to the ratchet wheels (308) are provided in the panel (1). The two sets of pawls (309) are respectively engaged with the corresponding ratchet wheels (308). The two sets of pawls (309) are rotatably connected to the panel (1) through rotating rods (310). A second torsion spring (311) is sleeved on the two sets of rotating rods (310). The two ends of the second torsion spring (311) are respectively fixedly connected to the pawls (309) and the panel (1). A third gear (312) is sleeved on the lower end of the two sets of rotating rods (310). Two sets of third racks (313) that are engaged with the third gear (312) are slidably installed in the panel (1).
3. The honeycomb sandwich sheet metal lightweight structure according to claim 1, characterized in that: A connecting frame (314) is slidably installed inside the panel (1), and the connecting frame (314) is fixedly connected to two sets of third racks (313). A third slide rod (315) corresponding to the connecting frame (314) is fixedly installed inside the panel (1). The connecting frame (314) and the corresponding third slide rod (315) are slidably sleeved together, and two sets of symmetrically distributed third springs (316) are sleeved on the third slide rod (315). The two ends of the two sets of third springs (316) are fixedly connected to the connecting frame (314) and the panel (1) respectively. A locking block (317) is fixedly installed on the connecting frame (314).
4. The honeycomb sandwich sheet metal lightweight structure according to claim 1, characterized in that: The panel (1) is fixedly installed with a locking rod (318) corresponding to the locking block (317). Two sets of symmetrically distributed locking frames (319) are sleeved on the locking rod (318). The two sets of locking frames (319) are movably locked with the locking block (317). A third torsion spring (320) is sleeved on the locking rod (318). The two ends of the third torsion spring (320) are fixedly connected to the corresponding locking frames (319) and the locking rod (318) respectively.
5. The honeycomb sandwich sheet metal lightweight structure according to claim 1, characterized in that: The connecting mechanism (4) further includes two sets of second slides (402) slidably installed in the left core plate (2). The two sets of second slides (402) can be movably engaged with the connecting block (401). A second rack (403) is fixedly installed on each of the two sets of second slides (402). A second gear (404) is provided between the two sets of second racks (403). The second gear (404) meshes with the two sets of second racks (403) respectively. The second gear (404) is rotatably connected to the core plate (2) through the mounting shaft (405). The two sets of second slides (402) are centrally symmetrical about the mounting shaft (405). A pull rod (407) is rotatably installed in the core plate (2) and is perpendicular to the mounting shaft (405). Two sets of second slide rods (410) are fixedly installed in the core plate (2) and are correspondingly provided with the second slides (402).
6. The honeycomb sandwich sheet metal lightweight structure according to claim 5, characterized in that: A fourth torsion spring (406) is sleeved on both the mounting shaft (405) and the pull rod (407). The two ends of the fourth torsion spring (406) are fixedly connected to the corresponding mounting shaft (405) or pull rod (407) and the core plate (2), respectively. A first bevel gear (408) is sleeved on the mounting shaft (405), and a second bevel gear (409) is sleeved on the pull rod (407). The second bevel gear (409) meshes with the first bevel gear (408).
7. A honeycomb sandwich sheet metal lightweight structure according to claim 5, characterized in that: The second slide (402) is slidably sleeved with the corresponding second slide rod (410). Two sets of symmetrically distributed second springs (411) are sleeved on the second slide rod (410). The two ends of the two sets of second springs (411) are fixedly connected to the second slide (402) and the core plate (2) respectively.