Low altitude defense umbrella-shaped unmanned aerial vehicle interceptor net
Patent Information
- Application Number
- CN202522405225.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-13
- Publication Date
- 2026-10-23
- Estimated Expiration
- 2035-11-13
AI Technical Summary
[0004]有鉴于此,本实用新型的目的在于提出一种低空防护伞状无人机拦截网,以解决现有设计采用一体成型或焊接固定的筒状壳体,检修时,必须对整个壳体进行破坏性拆解或极其复杂的非标操作,导致维护周期长、成本高的问题
[0015]本实用新型的有益效果为采用高压气体驱动,实现了毫秒级的反应和展开速度,能够有效应对高速或近距离突然出现的无人机目标,网体在空中展开后形成远大于发射口径的伞状覆盖区,对目标的精准度要求降低,容错率高,大幅提升了单次拦截的成功率,同时将壳体分为前、中、后三段,可以分别开模制造,降低了生产难度和成本,降低了维护成本和时间,并三段式结构自然地将内部空间划分为后部动力区、中部控制与前部发射导向区,使得内部结构更紧凑、管线布置更合理,提升了系统的稳定性和可靠性。
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Figure CN224887783U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the technical field of low-altitude protective umbrella-shaped drone interception equipment, and in particular to a low-altitude protective umbrella-shaped drone interception net. Background Technology
[0002] In the field of low-altitude security, the technical approach of using physical interception nets to capture drones has become a key research focus due to its ability to avoid electromagnetic interference and target crash risks. However, existing ground-based interception net launching devices have significant defects in their overall structure, especially in the assembly and maintenance design of the interception shell, which severely restricts their reliability, maintainability, and practical application.
[0003] Currently, existing designs use a one-piece molded or welded cylindrical shell, encapsulating all critical components such as the power cylinder, release valve, and interception net housing mechanism within an inseparable cavity. Therefore, when maintenance or replacement is required, the entire shell must be destructively disassembled or subjected to extremely complex non-standard operations, resulting in long maintenance cycles and high costs. Utility Model Content
[0004] In view of this, the purpose of this utility model is to propose a low-altitude protective umbrella-shaped UAV interception net to solve the problem that the existing design uses an integrally molded or welded cylindrical shell, which requires destructive disassembly of the entire shell or extremely complex non-standard operations during maintenance, resulting in long maintenance cycles and high costs.
[0005] Based on the above objectives, this utility model provides a low-altitude protective umbrella-shaped UAV interception net, comprising: a connecting base; an interception shell connected to the connecting base, having a shell cavity with one end open; a release valve fixed inside the shell cavity, having a release end for rapidly releasing gas, the release end being positioned towards the opening of the shell cavity; a high-pressure gas cylinder inserted and fixed inside the shell cavity, having a gas connection end, the gas connection end being fixedly connected to the release valve; a receiving assembly fixed inside the shell cavity, positioned towards the opening of the shell cavity, having a receiving cavity and several receiving slots penetrating the receiving assembly at one end facing the opening of the shell cavity; and an interception net body placed inside the receiving cavity, having traction heads around its perimeter, the traction heads being inserted into corresponding receiving slots.
[0006] In an optional example, the interceptor housing includes a middle section of the outer shell, a front section of the outer shell fixed to one end of the middle section of the outer shell, and a rear section of the outer shell fixed to the other end of the middle section of the outer shell. A middle section cavity is provided inside the middle section of the outer shell, a front section cavity is provided inside the front section of the outer shell, and a rear section cavity is provided inside the rear section of the outer shell. The middle section cavity, the front section cavity, and the rear section cavity are combined to form a housing cavity, and the opening of the housing cavity is located in the front section of the outer shell.
[0007] In an optional example, the front section of the housing is provided with a tapered portion at one end away from the middle section of the housing. The receiving component is inserted into the front cavity from the opening of the tapered portion. A locking ring is fixed on the outer wall of the tapered portion. The end of the locking ring facing the middle section of the housing abuts against the receiving component and fixes the receiving component in the front cavity.
[0008] In an optional example, the receiving assembly includes a receiving block and a receiving shell. The receiving block is adapted to the inner cavity shape of the conical portion. A through-hole is formed on the receiving block along the central axis of the receiving block. An end through-hole is formed in the through-hole. The receiving shell is inserted and fixed in the through-hole. The receiving cavity is formed at the end of the receiving shell facing away from the middle section of the outer shell. The receiving through-hole is formed on the receiving block and is arranged in a ring direction with the end through-hole as the center.
[0009] In an alternative example, the housing is provided with a tapered guide at one end facing the middle section of the outer shell.
[0010] In an optional example, a support plate is provided in the middle section cavity, and a positioning groove is provided on the support plate. The release valve is inserted into the positioning groove and fixedly connected to the support plate. An air passage groove is provided in the positioning groove, and the release end passes through the air passage groove and communicates with the front section cavity.
[0011] In an alternative example, the high-pressure gas cylinder is inserted into the rear cavity.
[0012] In an optional example, the receiving block has a plurality of guide grooves at one end facing away from the middle of the outer shell, one end of the guide groove is connected to the airflow groove, and the other end of the guide groove is connected to the insertion groove.
[0013] In an optional example, the front section of the housing is fixedly connected to one end of the middle section of the housing by a threaded connection, and the rear section of the housing is fixedly connected to the other end of the middle section of the housing by a threaded connection.
[0014] In an optional example, a support ring is fixed on the outer wall of the interceptor housing, a connecting block is provided on the support ring, a connecting threaded hole is provided on the connecting block, a connecting through hole is provided on the connecting base, a connecting bolt is inserted into the connecting through hole, and the connecting bolt is connected to the connecting threaded hole by a threaded connection.
[0015] The beneficial effects of this utility model are that it adopts high-pressure gas drive, achieving millisecond-level reaction and deployment speed, which can effectively deal with high-speed or close-range suddenly appearing UAV targets. After the net is deployed in the air, it forms an umbrella-shaped coverage area much larger than the launch aperture, reducing the accuracy requirements of the target, increasing the fault tolerance rate, and greatly improving the success rate of single interception. At the same time, the shell is divided into three sections: front, middle and rear, which can be manufactured by molds separately, reducing production difficulty and cost, and reducing maintenance costs and time. The three-section structure naturally divides the internal space into the rear power area, the middle control area and the front launch guidance area, making the internal structure more compact and the pipeline layout more reasonable, thus improving the stability and reliability of the system. Attached Figure Description
[0016] To more clearly illustrate the technical solutions in this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only for this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0017] Figure 1 This is a three-dimensional structural diagram of an embodiment of the present utility model; Figure 2 A three-dimensional cross-sectional view of an embodiment of this utility model. Figure 1 ; Figure 3 This is a schematic diagram of the structure of the interception net body in an embodiment of this utility model; Figure 4 A three-dimensional cross-sectional view of an embodiment of this utility model. Figure 2 ; Figure 5 This is a schematic diagram of the exploded structure of an embodiment of the present utility model. Figure 1 ; Figure 6 This is a schematic diagram of the exploded structure of an embodiment of the present utility model. Figure 2 .
[0018] The markings in the diagram are as follows: 1. Connecting base; 11. Connecting through hole; 2. Interception shell; 21. Shell cavity; 22. Middle section of outer shell; 221. Middle section cavity; 222. Support plate; 223. Positioning groove; 224. Airflow groove; 23. Front section of outer shell; 231. Front section cavity; 232. Conical part; 24. Rear section of outer shell; 241. Rear section cavity; 25. Locking ring; 3. Release valve; 31. Release end; 4. High-pressure gas cylinder; 41. Gas connection end; 5. Receiving assembly; 51. Receiving cavity; 52. Receiving through groove; 53. Receiving block; 531. Insertion groove; 532. End through groove; 533. Guide groove; 54. Receiving shell; 541. Conical guide part; 6. Interception net body; 61. Traction head; 62. Connecting rope; 7. Support ring; 71. Connecting block; 72. Connecting threaded hole; 8. Connecting bolt. Detailed Implementation
[0019] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to specific embodiments.
[0020] It should be noted that, unless otherwise defined, the technical or scientific terms used in this utility model should have the ordinary meaning understood by one of ordinary skill in the art to which this utility model pertains. The terms "first," "second," and similar terms used in this utility model do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed following the word and their equivalents, without excluding other elements or objects. Terms such as "connected" or "linked" are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.
[0021] In one embodiment, please refer to Figures 1 to 3 As shown, the present invention provides a low-altitude protective umbrella-shaped drone interception net, comprising: a connecting base 1, an interception shell 2, a release valve 3, a high-pressure gas cylinder 4, a housing component 5, and an interception net body 6.
[0022] The connecting base 1 serves as the foundation of the entire device, used to secure the low-altitude protective umbrella-shaped drone interception net to ground vehicles, rooftops, or other protective platforms.
[0023] The interceptor housing 2 is connected to the connecting base 1 and has a housing cavity 21 with one end open to accommodate all core components.
[0024] The gas release valve 3 is fixed inside the housing cavity 21 and has a release end 31 for rapid gas release, with the release end 31 facing the opening of the housing cavity 21.
[0025] The high-pressure gas cylinder 4 is inserted and fixed inside the housing cavity 21, and has a gas connection end 41, which is fixedly connected to the release valve 3. The gas connection end 41 can be connected to the release valve 3 by means of a threaded connection.
[0026] The receiving component 5 is fixed inside the housing cavity 21 and is arranged in the direction of the opening of the housing cavity 21. The end of the receiving component 5 facing the direction of the opening of the housing cavity 21 is provided with a receiving cavity 51 and a plurality of receiving slots 52 that penetrate the receiving component 5. The interception net body 6 is normally folded and stored in the receiving cavity 51. It has traction heads 61 around its perimeter, which are inserted into the corresponding receiving slots 52. Connecting ropes 62 are provided around the interception net body 6, and the ends of the connecting ropes 62 are fixedly connected to the traction heads 61.
[0027] During operation, the operator opens the release valve 3 instantly, and the compressed gas in the high-pressure gas cylinder 4 is ejected at high speed through the release valve 3 towards the opening of the shell cavity 21. The high-speed airflow first impacts the folded interception net body 6, while at the same time, a huge thrust acts on the traction heads 61 around the net body. Under the action of the gas thrust, the traction heads 61 are quickly pulled out from the receiving slot 52, thereby instantly dragging and launching the entire interception net body 6. Since multiple traction heads 61 are launched in different directions, they will quickly unfold the net body in the air, forming a huge umbrella-shaped or spider web-shaped coverage area, facing the target drone, and finally entangling and capturing it.
[0028] Specifically, this example uses high-pressure gas drive to achieve millisecond-level reaction and deployment speed, which can effectively deal with high-speed or close-range drone targets that suddenly appear. After the net is deployed in the air, it forms an umbrella-shaped coverage area that is much larger than the launch aperture, reducing the accuracy requirements of the target, increasing the fault tolerance rate, and greatly improving the success rate of single interception.
[0029] In an optional example, please refer to Figures 1 to 6As shown, the interceptor shell 2 includes a middle section 22, a front section 23 fixed to one end of the middle section 22, and a rear section 24 fixed to the other end of the middle section 22. A middle cavity 221 is provided inside the middle section 22, a front cavity 231 is provided inside the front section 23, and a rear cavity 241 is provided inside the rear section 24. The middle cavity 221, the front cavity 231, and the rear cavity 241 combine to form a shell cavity 21. The opening of the shell cavity 21 is located in the front section 23. The rear section 24 is typically used to securely mount the high-pressure gas cylinder 4, providing solid support. The middle section 22 can be used to house the release valve 3, some pipelines, and the base for the housing assembly 5. The front section 23 serves as a launch guidance channel, with its internal housing cavity 51 directly facing the opening, ensuring that the interceptor net can be accurately guided towards the target.
[0030] Specifically, this example divides the shell into three sections, which can be manufactured separately using molds, reducing production difficulty and cost. If a part is damaged during transportation or use, only the damaged module can be replaced without scrapping the entire shell, greatly reducing maintenance costs and time. At the same time, the three-section structure naturally divides the internal space into a rear power zone, a middle control zone, and a front launch guidance zone, making the internal structure more compact and the pipeline layout more reasonable, improving the stability and reliability of the system. Furthermore, the front section 23 of the shell forms a clear launch tube, which can constrain and guide the initial flight direction of the high-pressure gas and the interceptor net, helping to reduce energy loss, increase the initial velocity and straightness of the launch, and thus improve the interception accuracy.
[0031] In an optional example, please refer to Figures 1 to 6 As shown, a tapered portion 232 is provided at the end of the front section 23 of the outer casing away from the middle section 22. The receiving component 5 is inserted into the front cavity 231 through the opening of the tapered portion 232. A locking ring 25 is fixed on the outer wall of the tapered portion 232. The end of the locking ring 25 facing the middle section 22 of the outer casing abuts against the receiving component 5 and fixes the receiving component 5 in the front cavity 231. The locking ring 25 is threaded onto the outer wall of the tapered portion 232.
[0032] Specifically, this example pre-installs the housing component 5 as a separate module. When a reset or reloading is required, simply loosen the locking ring 25 to quickly pull out the old housing component 5 from the front and insert the new module, achieving rapid relaunch and greatly improving operational efficiency and maintenance convenience.
[0033] In an optional example, please refer to Figures 1 to 6As shown, the receiving component 5 includes a receiving block 53 and a receiving housing 54. The receiving block 53 is adapted to the inner cavity shape of the conical portion 232. A insertion groove 531 is formed on the receiving block 53 along the central axis of the receiving block 53, and an end through groove 532 is formed in the insertion groove 531, which penetrates the receiving block 53. The receiving housing 54 is inserted and fixed in the insertion groove 531. The receiving cavity 51 is formed at one end of the receiving housing 54 facing away from the middle section 22 of the outer shell. The receiving through groove 52 is formed on the receiving block 53 and is arranged in a ring direction with the end through groove 532 as the center. The receiving block 53 is mainly responsible for structural support, force transmission and airflow passage. It can be made of high-strength, wear-resistant metal or engineering plastic to withstand the impact of high-pressure gas and the friction of the traction head 61. Specifically, in this example, the through slot 52 is arranged in a ring around the end through slot 532, which is the core mechanical structure for forming an umbrella-shaped interception net. It ensures that multiple towing heads 61 are simultaneously and symmetrically launched in different directions, so that the net can be stretched into a circular coverage area in the air, which greatly improves the capture probability.
[0034] In an optional example, please refer to Figures 1 to 6 As shown, a tapered guide section 541 is provided at one end of the housing 54 facing the middle section 22 of the outer shell. When the release valve 3 is opened, the high-pressure gas rushes from the wide middle section cavity 221 to the front section cavity 231 and will first hit the rear end of the housing 54.
[0035] Specifically, in this example, the tapered guide section 541 is used as a smooth transition slope, which can smoothly guide and converge the impact airflow that might otherwise generate turbulence to the central end slot 532 of the receiving block 53 and the surrounding annular receiving slot 52 area, while avoiding the formation of gas vortices or dead zones at the rear end of the receiving housing 54, thus greatly reducing the resistance to gas flow.
[0036] In an optional example, please refer to Figures 1 to 6 As shown, a support plate 222 is provided in the middle section cavity 221. A positioning groove 223 is provided on the support plate 222. The release valve 3 is inserted into the positioning groove 223 and fixedly connected to the support plate 222. An air flow groove 224 is provided in the positioning groove 223. The release end 31 passes through the air flow groove 224 and is connected to the front section cavity 231.
[0037] Specifically, when the release valve 3 releases high-pressure gas instantaneously, it will be subjected to a huge reaction force. The support plate 222, as a sturdy frame, evenly distributes this force to the entire interceptor housing 2, preventing the valve from shaking or loosening in the cavity, thus ensuring the stability and safety of the launch. At the same time, the design of the positioning groove 223 ensures that the release valve 3 is installed in the preset precise position, so that its release end 31 can be accurately aligned with the direction of the gas flow groove 224 and the front cavity 231.
[0038] In an optional example, please refer to Figures 1 to 6 As shown, the high-pressure gas cylinder 4 is inserted into the rear cavity 241.
[0039] Specifically, in this example, the high-pressure gas cylinder 4 is placed in the rear cavity 241 to facilitate the disassembly, assembly, and maintenance of the high-pressure gas cylinder 4.
[0040] In an optional example, please refer to Figures 1 to 6 As shown, the receiving block 53 has several guide grooves 533 at one end facing away from the middle section 22 of the outer shell. One end of the guide groove 533 is connected to the airflow groove 224, and the other end of the guide groove 533 is connected to the insertion groove 531. The guide groove 533 is used to receive the connecting rope 62.
[0041] Specifically, this example ensures that all traction heads 61 are subjected to uniform force through the cooperation of the guide groove 533 and the connecting rope 62, and that the net unfolding process is extremely orderly and stable, avoiding the connecting ropes 62 from getting tangled or hooked together, which could cause the net to fail to unfold or even tear.
[0042] In an optional example, please refer to Figures 1 to 6 As shown, the front section 23 of the outer shell is fixedly connected to one end of the middle section 22 of the outer shell by a threaded connection, and the rear section 24 of the outer shell is fixedly connected to the other end of the middle section 22 of the outer shell by a threaded connection. Both ends of the middle section 22 of the outer shell are provided with internal threads, and the outer walls of the front section 23 and the rear section 24 of the outer shell are provided with external threads that match the internal threads.
[0043] Specifically, in this example, the middle section 22 of the outer shell is connected to the front section 23 and the rear section 24 of the outer shell by means of a threaded connection, which facilitates the quick assembly and disassembly of the intercepting shell 2.
[0044] In an optional example, please refer to Figures 1 to 6 As shown, a support ring 7 is fixed on the outer wall of the interceptor housing 2. A connecting block 71 is provided on the support ring 7. A connecting threaded hole 72 is provided on the connecting block 71. A connecting through hole 11 is provided on the connecting base 1. A connecting bolt 8 is inserted into the connecting through hole 11. The connecting bolt 8 is connected to the connecting threaded hole 72 by means of threaded connection.
[0045] Specifically, in this example, the connecting base 1 is quickly positioned and fixed by the cooperation of the connecting bolt 8 and the connecting block 71, thus realizing the rapid installation of the interceptor shell 2.
[0046] In summary, this invention utilizes high-pressure gas drive to achieve millisecond-level reaction and deployment speeds, effectively addressing high-speed or close-range sudden appearances of UAV targets. After deployment in the air, the net forms an umbrella-shaped coverage area much larger than the launch aperture, reducing the accuracy requirements for targets, increasing the fault tolerance rate, and significantly improving the success rate of single interception. Furthermore, the shell is divided into front, middle, and rear sections, allowing for separate mold manufacturing, reducing production difficulty and costs, as well as maintenance costs and time. The three-section structure naturally divides the internal space into a rear power zone, a middle control zone, and a front launch guidance zone, resulting in a more compact internal structure, a more rational pipeline layout, and improved system stability and reliability.
[0047] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the present invention (including the claims) is limited to these examples; within the framework of the present invention, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of the different aspects of the present invention as described above, which are not provided in the details for the sake of brevity.
[0048] This utility model is intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.
Claims
1. A low-altitude protective umbrella-shaped drone interception net, characterized in that, include: Connecting base (1); The interceptor housing (2) is connected to the connecting base (1) and has a housing cavity (21) with one end open; A gas release valve (3) is fixed inside the housing cavity (21) and has a release end (31) for rapidly releasing gas, the release end (31) being disposed toward the opening of the housing cavity (21); A high-pressure gas cylinder (4) is inserted and fixed inside the housing cavity (21) and has a gas connection end (41), which is fixedly connected to the gas release valve (3). The receiving component (5) is fixed inside the housing cavity (21) and is arranged in the direction of the opening of the housing cavity (21). One end of the receiving component (5) facing the direction of the opening of the housing cavity (21) is provided with a receiving cavity (51) and a plurality of receiving through slots (52) penetrating the receiving component (5). The interception net body (6) is placed in the receiving cavity (51), and has traction heads (61) around its perimeter. The traction heads (61) are inserted into the corresponding receiving slots (52).
2. The low-altitude protective umbrella-shaped UAV interception net according to claim 1, characterized in that, The interceptor housing (2) includes a middle section (22) of the outer shell, a front section (23) of the outer shell is fixed at one end of the middle section (22), and a rear section (24) of the outer shell is fixed at the other end of the middle section (22). A middle section cavity (221) is provided inside the middle section (22), a front section cavity (231) is provided inside the front section (23), and a rear section cavity (241) is provided inside the rear section (24). The middle section cavity (221), the front section cavity (231), and the rear section cavity (241) are combined to form a housing cavity (21). The opening of the housing cavity (21) is located in the front section (23).
3. The low-altitude protective umbrella-shaped UAV interception net according to claim 2, characterized in that, The front section (23) of the outer shell has a tapered portion (232) at one end away from the middle section (22). The receiving component (5) is inserted into the front cavity (231) from the opening of the tapered portion (232). A locking ring (25) is fixed on the outer wall of the tapered portion (232). The end of the locking ring (25) facing the middle section (22) of the outer shell abuts against the receiving component (5) and fixes the receiving component (5) in the front cavity (231).
4. The low-altitude protective umbrella-shaped UAV interception net according to claim 3, characterized in that, The receiving assembly (5) includes a receiving block (53) and a receiving shell (54). The receiving block (53) is adapted to the inner cavity shape of the conical part (232). A insertion groove (531) is provided on the receiving block (53) along the central axis direction of the receiving block (53). An end through groove (532) is provided in the insertion groove (531). The receiving shell (54) is inserted and fixed in the insertion groove (531). The receiving cavity (51) is opened at one end of the receiving shell (54) facing away from the middle section (22) of the outer shell. The receiving through groove (52) is opened on the receiving block (53) and is arranged in a ring direction with the end through groove (532) as the center.
5. The low-altitude protective umbrella-shaped UAV interception net according to claim 4, characterized in that, The housing (54) has a tapered guide section (541) at one end facing the middle section (22) of the outer shell.
6. The low-altitude protective umbrella-shaped UAV interception net according to claim 5, characterized in that, A support plate (222) is provided in the middle section cavity (221). A positioning groove (223) is provided on the support plate (222). The release valve (3) is inserted into the positioning groove (223) and fixedly connected to the support plate (222). An air passage groove (224) is provided in the positioning groove (223). The release end (31) passes through the air passage groove (224) and is connected to the front section cavity (231).
7. The low-altitude protective umbrella-shaped UAV interception net according to claim 6, characterized in that, The high-pressure gas cylinder (4) is inserted into the rear cavity (241).
8. The low-altitude protective umbrella-shaped UAV interception net according to claim 7, characterized in that, The receiving block (53) has several guide grooves (533) at one end facing away from the middle section (22) of the outer shell. One end of the guide groove (533) is connected to the airflow groove (224), and the other end of the guide groove (533) is connected to the insertion groove (531).
9. The low-altitude protective umbrella-shaped UAV interception net according to claim 8, characterized in that, The front section (23) of the outer shell is fixedly connected to one end of the middle section (22) of the outer shell by means of a threaded connection, and the rear section (24) of the outer shell is fixedly connected to the other end of the middle section (22) of the outer shell by means of a threaded connection.
10. The low-altitude protective umbrella-shaped UAV interception net according to claim 1, characterized in that, A support ring (7) is fixed on the outer wall of the interceptor housing (2). A connecting block (71) is provided on the support ring (7). A connecting threaded hole (72) is provided on the connecting block (71). A connecting through hole (11) is provided on the connecting base (1). A connecting bolt (8) is inserted into the connecting through hole (11). The connecting bolt (8) is connected to the connecting threaded hole (72) by means of threaded connection.