Suspension copper plate and double-layer propulsion coil integrated module structure assembly

Abstract

The utility model discloses a suspended copper plate and double-layer propulsion coil integrated module structure assembly. The suspended copper plate and double-layer propulsion coil integrated module structure assembly comprises an insulating substrate used for being connected with a track beam, a double-layer propulsion coil module installed in the middle of the front side of the insulating substrate and two suspended copper plate modules symmetrically installed on the upper portion and the lower portion of the front side of the insulating substrate respectively. A plurality of first key groove positioning structures used for transverse positioning and longitudinal positioning, a plurality of second key groove positioning structures used for vertical positioning and longitudinal positioning and a plurality of first screw locking structures used for longitudinal locking are arranged between the front side of the insulating substrate and the rear side of the double-layer propelling coil module. A positioning face structure used for vertical positioning, a plurality of third key groove positioning structures used for transverse positioning and longitudinal positioning and a plurality of second screw locking structures used for vertical locking are arranged between the front side of the insulation substrate and the rear side of the suspension copper plate module. According to the utility model, the structure support reliability and the assembly precision can be improved.

Description

Technical Field

[0001] This utility model belongs to the field of linear motor technology, and in particular relates to an integrated module structure assembly of a suspended copper plate and a double-layer propulsion coil. Background Technology

[0002] The copper plate electric levitation system comprises superconducting coils and two suspended copper plates on both sides, which has advantages such as self-stabilizing levitation guidance, large levitation gap, high levitation guidance stiffness, and low harmonic disturbance. The double-layer staggered superconducting linear synchronous motor system comprises double-layer hollow coils and superconducting coils, which has advantages such as high thrust density, low harmonic disturbance, and high efficiency. Therefore, the linear superconducting magnetic levitation electromagnetic propulsion system formed by combining the copper plate electric levitation system and the double-layer staggered superconducting linear synchronous motor system has broad application prospects in high thrust and ultra-high speed electromagnetic launch.

[0003] However, the copper plate electric suspension system is a pure repulsive force suspension system, and each suspension plate must bear a huge suspension guiding force, which means that the requirements for the reliability of the structural support are high. In addition, the copper plate electric suspension system has a large suspension guiding stiffness, and uneven track will generate a large amount of disturbance to the aircraft, which means that the requirements for the assembly precision of the entire suspension copper plate and the double-layer propulsion coil are high. Utility Model Content

[0004] To overcome the shortcomings of existing technologies, this utility model provides an integrated module structure assembly of a suspended copper plate and a double-layer propulsion coil, which can improve the reliability of structural support and assembly accuracy.

[0005] The objective of this utility model is achieved through the following technical solution:

[0006] An integrated module structure assembly of a suspended copper plate and a double-layer propulsion coil includes an insulating substrate for connecting a track beam, a double-layer propulsion coil module installed in the middle of the front side of the insulating substrate, and two suspended copper plate modules respectively symmetrically installed in the upper and lower parts of the front side of the insulating substrate.

[0007] Between the front side of the insulating substrate and the rear side of the double-layer push coil module, there are several first keyway positioning structures for lateral and longitudinal positioning, several second keyway positioning structures for vertical and longitudinal positioning, and several first screw locking structures for longitudinal locking.

[0008] Between the front side of the insulating substrate and the rear side of the suspended copper plate module, there is a positioning surface structure for vertical positioning, several third keyway positioning structures for horizontal and vertical positioning, and several second screw locking structures for vertical locking.

[0009] Furthermore, the first keyway positioning structure includes a first positioning groove disposed on an insulating substrate and a first positioning key disposed on a double-layer push coil module. The first positioning groove extends vertically, and the first positioning key transitionally engages with the first positioning groove and fits against the bottom of the first positioning groove.

[0010] Furthermore, the second keyway positioning structure includes a second positioning groove disposed on an insulating substrate and a second positioning key disposed on a double-layer push coil module. The second positioning groove extends laterally, and the second positioning key transitionally engages with the second positioning groove and fits against the bottom of the second positioning groove.

[0011] Furthermore, the first screw locking structure includes a first threaded hole longitudinally disposed on the insulating substrate, a second threaded hole longitudinally disposed on the double-layer propulsion coil module, and a first screw threadedly connecting the first threaded hole and the second threaded hole.

[0012] Furthermore, the positioning surface structure includes a horizontal surface disposed on an insulating substrate, which is attached to one side of the suspended copper plate module.

[0013] Furthermore, the third keyway positioning structure includes a third positioning groove disposed on the insulating substrate and a third positioning key disposed on the floating copper plate module. The third positioning groove extends vertically, and the third positioning key transitionally engages with the third positioning groove and fits against the bottom of the third positioning groove.

[0014] Furthermore, the second screw locking structure includes a third threaded hole vertically disposed on the insulating substrate, a fourth threaded hole vertically disposed on the suspended copper plate module, and a second screw threadedly connecting the third threaded hole and the fourth threaded hole.

[0015] Furthermore, the insulating substrate is provided with a number of fourth positioning grooves, which are arranged in two rows and located at the upper and lower parts of the insulating substrate, respectively. The front side of the track beam is provided with a number of support protrusions for installation in the number of fourth positioning grooves.

[0016] Furthermore, a connecting cable is arranged on the rear side of the double-layer propulsion coil module, and a first outlet hole and a second outlet hole for passing through the connecting cable are respectively provided in the middle part of the insulating substrate and the track beam.

[0017] Furthermore, the double-layer propulsion coil module includes a front propulsion module and a rear propulsion module that are fixedly connected to each other, and the front propulsion coil and the rear propulsion coil are respectively provided in the front propulsion module and the rear propulsion module;

[0018] The upper and lower edges of the front propulsion coil have a first lead and a second lead extending to the rear side of the rear propulsion module. The middle of the rear propulsion module has a third lead and a fourth lead extending to the rear side. The first lead, the second lead, the third lead and the fourth lead are all electrically connected to connecting cables.

[0019] The beneficial effects of this utility model are as follows:

[0020] The insulating substrate and the double-layer drive coil module can be positioned laterally, longitudinally, and vertically using the first keyway positioning structure and the second keyway positioning structure. Furthermore, they can be fixedly connected to each other using the first screw locking structure, which improves the assembly accuracy and structural support reliability between the insulating substrate and the double-layer drive coil module. The insulating substrate and the suspended copper plate module can be positioned laterally, longitudinally, and vertically using the positioning surface structure and the third keyway positioning structure. Furthermore, they can be fixedly connected to each other using the second screw locking structure, which improves the assembly accuracy and structural support stability between the insulating substrate and the suspended copper plate module. Therefore, the structural support reliability and assembly accuracy of this invention are improved. Attached Figure Description

[0021] The present invention will be described in more detail below based on embodiments and with reference to the accompanying drawings.

[0022] in:

[0023] Figure 1 A schematic diagram of the structure of this utility model is shown;

[0024] Figure 2 An isometric view of this utility model is shown;

[0025] Figure 3 An exploded view of this utility model is shown;

[0026] Figure 4 This invention displays a schematic diagram of the structure of the double-layer propulsion coil module.

[0027] Figure 5 An installation diagram of this utility model is shown;

[0028] In the accompanying drawings, the same parts use the same reference numerals. The drawings are not to scale.

[0029] Figure label:

[0030] 1. Insulating substrate; 101. Third positioning groove; 102. Fourth positioning groove; 103. Third threaded hole; 104. Horizontal plane; 105. First cable outlet hole; 106. First positioning groove; 107. Second positioning groove; 2. Floating copper plate module; 201. Third positioning key; 202. Second screw; 3. Double-layer propulsion coil module; 301. Front propulsion module; 302. Rear propulsion module; 303. Front propulsion coil; 304. Rear propulsion coil; 305. First lead wire; 306. Third lead wire; 307. Second lead wire; 308. Fourth lead wire; 309. Connecting cable; 310. First positioning key; 311. Second positioning key; 4. Track beam; 401. Second cable outlet hole; 402. Support protrusion. Detailed Implementation

[0031] The present invention will be further described below with reference to the accompanying drawings.

[0032] Currently, the world's only superconducting electric levitation test line that has successfully achieved Mach-level verification is the test line at Holloman Air Force Base in the United States. It installs upper and lower levitation copper plates in high-precision prefabricated plates and performs fine-tuning on the prefabricated plate bases throughout the line. However, its system does not have a linear motor component, so it does not need to consider the matching problem between the motor coil and the levitation copper plate or the wiring problem of the motor coil.

[0033] The test line has the following problems:

[0034] If the upper and lower suspended copper plates and the middle motor coil are installed as independent modules in the track beam, the entire line will need to be fine-tuned three times. This will result in a huge workload, high cost for long-distance laying, and the cumulative installation error of individual fine-tuning will affect the absolute distance between the propulsion coil and the suspended plate.

[0035] The propulsion module and the suspended copper plate are installed independently in the track beam, which limits the vertical installation space and requires three separate high-strength vertical structural support devices, which will increase the construction cost of the line.

[0036] There is no precedent for the integrated design of the double-layer propulsion coil and the upper and lower suspended copper plates. Furthermore, there are problems such as the difficulty in arranging and leading out the interconnection of the double-layer coil sandwiched in the middle and the obstruction of the upper and lower suspended copper plates. There is also the problem of mutual interference between the middle propulsion coil and the structural support components of the upper and lower suspended copper plates.

[0037] Therefore, this utility model provides an integrated module structure assembly of a suspended copper plate and a double-layer propulsion coil, such as... Figure 1-5 As shown, it includes an insulating base plate 1 for connecting the track beam 4, a double-layer propulsion coil module 3 installed in the middle of the front side of the insulating base plate 1, and two suspended copper plate modules 2 respectively symmetrically installed in the upper and lower parts of the front side of the insulating base plate 1.

[0038] Between the front side of the insulating substrate 1 and the rear side of the double-layer push coil module 3, there are a number of first keyway positioning structures for lateral and longitudinal positioning, a number of second keyway positioning structures for vertical and longitudinal positioning, and a number of first screw locking structures for longitudinal locking.

[0039] Between the front side of the insulating substrate 1 and the rear side of the suspended copper plate module 2, there is a positioning surface structure for vertical positioning, three sets of third keyway positioning structures for horizontal and vertical positioning, and several second screw locking structures for vertical locking.

[0040] In the longitudinal direction, the two suspended copper plate modules 2 have identical structures.

[0041] It is understood that the insulating substrate 1 and the double-layer push coil module 3 can achieve lateral, longitudinal, and vertical positioning by relying on the first keyway positioning structure and the second keyway positioning structure, and can be fixedly connected to each other by relying on the first screw locking structure, which is beneficial to improving the assembly accuracy and structural support reliability between the insulating substrate 1 and the double-layer push coil module 3; the insulating substrate 1 and the suspended copper plate module 2 can achieve lateral, longitudinal, and vertical positioning by relying on the positioning surface structure and the third keyway positioning structure, and can be fixedly connected to each other by relying on the second screw locking structure, which is beneficial to improving the assembly accuracy and structural support stability between the insulating substrate 1 and the suspended copper plate module 2; therefore, the structural support reliability and assembly accuracy of this utility model are improved.

[0042] It should be noted that by positioning and installing the insulating substrate 1 and the double-layer propulsion coil module 3 in the horizontal, vertical and vertical directions, the propulsion module is suspended and the propulsion electromagnetic force is transmitted to the insulating substrate 1, and the first screw locking structure is fixed on the guide and bears the outward pulling force of the guide.

[0043] It should be noted that the floating copper plate module 2 and the insulating substrate 1 are connected by three sets of third keyway positioning structures in a transitional fit manner to achieve high-precision positioning of the propulsion and guiding direction, so as to transmit the propulsion and guiding force of the floating copper plate module 2 to the insulating substrate 1, and the second screw locking structure is fixed in the vertical direction and bears the vertical outward pulling force.

[0044] It should also be noted that the insulating substrate 1 is a high-strength insulating structure, which includes, but is not limited to, fiberglass laminate, resin casting board and fiber concrete casting board; the suspended copper plate module 2 includes a copper plate and an insulating base, and the copper plate and the insulating base are connected to each other by resin adhesive and bolts.

[0045] In one embodiment, the first keyway positioning structure includes a first positioning groove 106 disposed on an insulating substrate 1 and a first positioning key 310 disposed on a double-layer push coil module 3. The first positioning groove 106 extends vertically, and the first positioning key 310 transitionally engages with the first positioning groove 106 and is in contact with the bottom of the first positioning groove 106.

[0046] Understandably, the sidewall of the first positioning groove 106 can restrict the lateral movement of the first positioning key 310, and the bottom of the first positioning groove 106 can restrict the longitudinal movement of the second positioning key 311, so as to install the double-layer push coil in lateral and longitudinal positioning on the insulating substrate 1.

[0047] In one embodiment, the second keyway positioning structure includes a second positioning groove 107 disposed on the insulating substrate 1 and a second positioning key 311 disposed on the double-layer push coil module 3. The second positioning groove 107 extends laterally, and the second positioning key 311 transitionally engages with the second positioning groove 107 and fits against the bottom of the second positioning groove 107.

[0048] Understandably, the sidewall of the second positioning groove 107 can restrict the vertical movement of the second positioning key 311, and the bottom of the second positioning groove 107 can restrict the longitudinal movement of the second positioning key 311, so as to install the double-layer push coil in vertical and longitudinal positioning on the insulating substrate 1.

[0049] In one embodiment, the first screw locking structure includes a first threaded hole longitudinally disposed on the insulating substrate 1, a second threaded hole longitudinally disposed on the double-layer propulsion coil module 3, and a first screw threadedly connecting the first threaded hole and the second threaded hole.

[0050] In one embodiment, the positioning surface structure includes a horizontal surface 104 disposed on an insulating substrate 1, the horizontal surface 104 being attached to one side of a suspended copper plate module 2; wherein, the upper horizontal surface 104 of the insulating substrate 1 is attached to the lower side of a suspended copper plate module 2, and the lower horizontal surface 104 of the insulating substrate 1 is attached to the upper side of another suspended copper plate module 2, so as to ensure vertical spacing consistency.

[0051] In one embodiment, the third keyway positioning structure includes a third positioning groove 101 disposed on the insulating substrate 1 and a third positioning key 201 disposed on the suspended copper plate module 2. The third positioning groove 101 extends vertically, and the third positioning key 201 transitionally engages with the third positioning groove 101 and fits against the bottom of the third positioning groove 101.

[0052] Understandably, the sidewall of the third positioning groove 101 can restrict the lateral movement of the third positioning key 201, and the bottom of the third positioning groove 101 can restrict the longitudinal movement of the third positioning key 201, so as to install the double-layer push coil in lateral and longitudinal positioning on the insulating substrate 1.

[0053] In one embodiment, the second screw locking structure includes a third threaded hole 103 vertically disposed on the insulating substrate 1, a fourth threaded hole vertically disposed on the suspended copper plate module 2, and a second screw 202 threadedly connecting the third threaded hole 103 and the fourth threaded hole.

[0054] It should be noted that during transition fit installation, the fit and positioning are achieved by striking with a rubber mallet or wooden mallet to provide sub-millimeter level assembly accuracy.

[0055] In one embodiment, the insulating substrate 1 is provided with a plurality of fourth positioning grooves 102, which are arranged in two rows and located at the upper and lower parts of the insulating substrate 1, respectively. The front side of the track beam 4 is provided with a plurality of support protrusions 402 for installation in the plurality of fourth positioning grooves 102. Correspondingly, the plurality of support protrusions 402 are also arranged in two rows, and the spacing between the rows is consistent at all locations. The size of the fourth positioning groove 102 is larger than that of the support protrusion 402, so that a certain gap is maintained between the fourth positioning groove 102 and the support protrusion 402, so as to adjust the spatial position of the integrated module structure assembly of the suspended copper plate and the double-layer propulsion coil.

[0056] It should be noted that the support protrusion 402 can be a concrete block, a pre-embedded steel plate, or other high-strength, high-precision pre-embedded parts.

[0057] In one embodiment, a connecting cable 309 is arranged on the rear side of the double-layer propulsion coil module 3, and a first outlet hole 105 and a second outlet hole 401 for passing the connecting cable 309 are respectively provided in the middle part of the insulating substrate 1 and the track beam 4.

[0058] In one embodiment, the double-layer propulsion coil module 3 includes a front propulsion module 301 and a rear propulsion module 302 that are fixedly connected to each other. The front propulsion module 301 and the rear propulsion module 302 are respectively provided with a front propulsion coil 303 and a rear propulsion coil 304.

[0059] The upper and lower edges of the front propulsion coil 303 have a first lead 305 and a second lead 307 extending to the rear side of the rear propulsion module 302. The middle of the rear propulsion module 302 has a third lead 306 and a fourth lead 308 extending to the rear side. The first lead 305, the second lead 307, the third lead 306 and the fourth lead 308 are connected in series at the rear center of the double-layer propulsion coil module 3, and finally led out from the first outlet hole 105 and the second outlet hole 401 through the connecting cable 309.

[0060] It should be noted that both the front propulsion module 301 and the rear propulsion module 302 have independent base plates and cover plates, and are manufactured separately. During assembly, the front propulsion module 301 and the rear propulsion module 302 are connected by bolts to the positioning keyway set on the top. Both the front propulsion coil 303 and the rear propulsion coil 304 are single-pane windings.

[0061] The installation process of this utility model is as follows:

[0062] Using the insulating substrate 1 and the double-layer propulsion coil module 3 as an installation module, the two rows of pre-set fourth positioning grooves 102 on the upper and lower parts of the insulating substrate 1 are respectively fastened onto the two rows of support protrusions 402 on the track beam 4.

[0063] The vertical and horizontal positions of the installation module on the track beam 4 are finely adjusted by inserting wedges and pads of different sizes between the fourth positioning groove 102 and the support protrusion 402. The guiding direction position of the installation module and the track beam 4 is finely adjusted by inserting wedges of different sizes, pads of different sizes, or using bolts and set screws between the insulating base plate 1 and the track beam 4. Finally, the three-degree-of-freedom precise adjustment between the installation module and the track beam 4 is achieved.

[0064] After adjustment, the insulating base plate 1 is fixed to the track beam 4 with bolts;

[0065] After the installation modules of the entire line are precisely adjusted and installed online, one side of the suspended copper plate module 2 is attached to the horizontal plane 104. Then, by hammering or other means, the third positioning key 201 of the suspended copper plate module 2 is assembled and attached to the third positioning groove 101 of the insulating substrate 1. This allows for high-precision positioning of the integrated module structure of the suspended copper plate and the double-layer propulsion coil in three degrees of freedom throughout the entire line without additional fine-tuning, through the closed loop of the dimensional chain.

[0066] Finally, the second screw 202 is used to fix the suspended copper plate module 2 and the insulating substrate 1 into a whole.

[0067] Based on the above solution, this utility model can reduce the structural complexity and cost of a single module by independently manufacturing the suspended copper plate module 2 and the double-layer propulsion coil module 3, and then assembling them together in the insulating substrate 1 using a keyway fit. This ensures high precision in the relative dimensions of the suspended copper plate module 2 and the double-layer propulsion coil module 3. The double-layer propulsion coil module 3 is formed independently at the front and rear, and the assembly method achieves high-precision positioning of the front and rear coil layers while ensuring sufficient insulation and support strength. In addition, by using this integrated module structure of the suspended copper plate and the double-layer propulsion coil for online installation, only one fine adjustment of the insulating substrate 1 is needed to achieve high-precision positioning of the integrated module structure of the suspended copper plate and the double-layer propulsion coil, and full-line three-degree-of-freedom adjustability can be achieved. Compared with the completely independent installation method, this greatly reduces the installation and fine-tuning time and cost.

[0068] In summary, this utility model can achieve high-precision installation and positioning of the upper and lower suspended copper plate modules 2 and the middle double-layer propulsion coil module 3 with only one fine adjustment throughout the entire line. In addition, the upper and lower suspended copper plate modules 2 can achieve high-precision and high-strength reliable positioning in the horizontal, vertical and guiding directions. This reduces the dependence on the track beam 4 support structure, reduces the line construction cost, and the assembly method is simple and easy to implement.

[0069] In the description of this utility model, it should be understood that the terms "upper", "lower", "bottom", "top", "front", "rear", "inner", "outer", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0070] While specific embodiments of the present invention have been described herein with reference to them, it should be understood that these embodiments are merely examples of the principles and applications of the present invention. Therefore, it should be understood that many modifications can be made to the exemplary embodiments, and other arrangements can be designed without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that different dependent claims and features described herein can be combined in ways different from those described in the original claims. It is also understood that features described in conjunction with individual embodiments can be used in other described embodiments.

Claims

1. An integrated module structure assembly of a suspended copper plate and a double-layer propulsion coil, characterized in that, It includes an insulating substrate (1) for connecting the track beam (4), a double-layer propulsion coil module (3) installed in the middle of the front side of the insulating substrate (1), and two suspended copper plate modules (2) respectively symmetrically installed in the upper and lower parts of the front side of the insulating substrate (1); Between the front side of the insulating substrate (1) and the rear side of the double-layer push coil module (3), there are a number of first keyway positioning structures for lateral and longitudinal positioning, a number of second keyway positioning structures for vertical and longitudinal positioning, and a number of first screw locking structures for longitudinal locking. Between the front side of the insulating substrate (1) and the rear side of the suspended copper plate module (2), there is a positioning surface structure for vertical positioning, several third keyway positioning structures for horizontal and vertical positioning, and several second screw locking structures for vertical locking.

2. The integrated module structure assembly of a suspended copper plate and a double-layer propulsion coil according to claim 1, characterized in that, The first keyway positioning structure includes a first positioning groove (106) disposed on the insulating substrate (1) and a first positioning key (310) disposed on the double-layer push coil module (3). The first positioning groove (106) extends vertically, and the first positioning key (310) transitionally engages with the first positioning groove (106) and is in contact with the bottom of the first positioning groove (106).

3. The integrated module structure assembly of a suspended copper plate and a double-layer propulsion coil according to claim 1 or 2, characterized in that, The second keyway positioning structure includes a second positioning groove (107) disposed on the insulating substrate (1) and a second positioning key (311) disposed on the double-layer push coil module (3). The second positioning groove (107) extends laterally, and the second positioning key (311) transitionally engages with the second positioning groove (107) and fits against the bottom of the second positioning groove (107).

4. The integrated module structure assembly of a suspended copper plate and a double-layer propulsion coil according to claim 1, characterized in that, The first screw locking structure includes a first threaded hole longitudinally disposed on the insulating substrate (1), a second threaded hole longitudinally disposed on the double-layer propulsion coil module (3), and a first screw threadedly connecting the first threaded hole and the second threaded hole.

5. The integrated module structure assembly of a suspended copper plate and a double-layer propulsion coil according to claim 1, characterized in that, The positioning surface structure includes a horizontal surface (104) disposed on the insulating substrate (1), and the horizontal surface (104) is attached to one side of the suspended copper plate module (2).

6. The integrated module structure assembly of a suspended copper plate and a double-layer propulsion coil according to claim 1, characterized in that, The third keyway positioning structure includes a third positioning groove (101) disposed on the insulating substrate (1) and a third positioning key (201) disposed on the suspended copper plate module (2). The third positioning groove (101) extends vertically, and the third positioning key (201) is in transition fit with the third positioning groove (101) and fits against the bottom of the third positioning groove (101).

7. The integrated module structure assembly of a suspended copper plate and a double-layer propulsion coil according to claim 1, characterized in that, The second screw locking structure includes a third threaded hole (103) vertically disposed on the insulating substrate (1), a fourth threaded hole vertically disposed on the suspended copper plate module (2), and a second screw (202) threadedly connecting the third threaded hole (103) and the fourth threaded hole.

8. The integrated module structure assembly of a suspended copper plate and a double-layer propulsion coil according to claim 1, characterized in that, The insulating substrate (1) is provided with a plurality of fourth positioning grooves (102), which are arranged in two rows and located at the upper and lower parts of the insulating substrate (1), respectively. The front side of the track beam (4) is provided with a plurality of support protrusions (402) for installation in the plurality of fourth positioning grooves (102).

9. The integrated module structure assembly of a suspended copper plate and a double-layer propulsion coil according to claim 1, characterized in that, A connecting cable (309) is arranged on the rear side of the double-layer propulsion coil module (3), and the middle part of the insulating substrate (1) and the track beam (4) are respectively provided with a first outlet hole (105) and a second outlet hole (401) for passing through the connecting cable (309).

10. The integrated module structure assembly of a suspended copper plate and a double-layer propulsion coil according to claim 9, characterized in that, The double-layer propulsion coil module (3) includes a front propulsion module (301) and a rear propulsion module (302) that are fixedly connected to each other. The front propulsion module (301) and the rear propulsion module (302) are respectively provided with a front propulsion coil (303) and a rear propulsion coil (304). The upper and lower edges of the front propulsion coil (303) have a first lead (305) and a second lead (307) extending to the rear side of the rear propulsion module (302). The middle part of the rear propulsion module (302) has a third lead (306) and a fourth lead (308) extending to the rear side. The first lead (305), the second lead (307), the third lead (306) and the fourth lead (308) are all electrically connected to the connecting cable (309).

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