Bolt assembly for waveguide tube and microwave transmission device

Abstract

The invention provides a bolt assembly for a waveguide tube and a microwave transmission device, and belongs to the field of fasteners. The bolt assembly comprises a bolt rod, an anti-loosening fastener, a main fastening nut and an anti-loosening nut. An anti-loosening hole is formed in the bolt rod in the axial direction in a penetrating mode, the bolt rod comprises a lead screw and a bolt head which are integrally connected, and an annular sealing groove used for preventing the bolt rod from rotating is formed in the clamping face of the bolt head; the main fastening nut is in threaded fit with the lead screw and used for providing initial clamping force for a connected piece. The anti-loosening fastener comprises a fastening head and a fastening rod, the fastening head is configured to be connected with the end, away from the bolt head, of the lead screw, and the fastening rod is configured to be arranged in the anti-loosening hole in a penetrating mode; the locknut is in threaded connection with the part, extending out of the bolt head, of the fastening rod, the fastening rod can be pulled by screwing down the locknut, then anti-loose locking is formed through interaction of the fastening head and the main fastening nut, and the extremely reliable anti-loose effect is achieved.

Description

Technical Field

[0001] This invention relates to the field of fasteners, and more specifically, to a bolt assembly for waveguides and a microwave transmission device. Background Technology

[0002] Waveguides are key components for transmitting high-frequency microwave signals, and they are typically connected by bolts via flanges. Because microwave signals require extremely high sealing during transmission, any gaps or loosening at the flange connection can lead to microwave signal leakage, reduced transmission efficiency, and even affect the stability of the entire system. Therefore, the reliability of the waveguide connection directly determines the performance of the entire microwave transmission system.

[0003] However, in existing technologies, ordinary bolts are prone to loosening under harsh conditions such as long-term vibration and thermal cycling, resulting in poor radio frequency sealing. Summary of the Invention

[0004] The purpose of this invention is to provide a bolt assembly for waveguides, which has a good anti-loosening effect and can improve the radio frequency sealing performance of waveguides.

[0005] Another object of the present invention is to provide a microwave transmission device that employs the above-described bolt assembly.

[0006] This invention is implemented as follows: A bolt assembly includes a bolt shank, a locking fastener, a main locking nut, and a locking nut; The bolt rod has an anti-loosening hole extending through it along its axial direction. It includes an integrally connected lead screw and bolt head. The clamping surface of the bolt head is provided with an annular sealing groove to prevent the bolt rod from rotating. The main fastening nut is threaded with the lead screw and is used to provide an initial clamping force to the connected parts; The anti-loosening fastener includes a fastening head and a fastening rod, the fastening head being configured to engage with the end of the lead screw away from the bolt head, and the fastening rod being configured to pass through the anti-loosening hole; The anti-loosening nut is threadedly connected to the fastening rod portion extending beyond the bolt head. Tightening the anti-loosening nut can cause the fastening rod to be under tension, thereby forming an anti-loosening lock through the interaction between the fastening head and the main fastening nut.

[0007] Furthermore, the anti-loosening hole is a cylindrical hole.

[0008] Furthermore, the fastening head is a cylindrical tube with one open end, and the fastening rod is connected to the inside of the cylindrical tube with one end closed; when the fastening rod passes through the anti-loosening hole and the anti-loosening nut is tightened, the cylindrical tube is sleeved on the outside of the lead screw and pressed against the main fastening nut.

[0009] Furthermore, the anti-loosening hole is a wedge-shaped hole that penetrates the lead screw radially, and the cross-sectional area of ​​the wedge-shaped hole gradually decreases from the end of the lead screw toward the bolt head.

[0010] Furthermore, the fastening head is a wedge-shaped block, and the fastening rod is connected to the end of the wedge-shaped block with a smaller cross-sectional area. The wedge-shaped block can be wedged into the wedge-shaped hole. When the fastening rod passes through the anti-loosening hole and the anti-loosening nut is tightened, the wedge-shaped block is wedged into the wedge-shaped hole, thereby tensioning the lead screw.

[0011] Furthermore, a limiting post is provided at the center of the end face of the bolt head away from the lead screw; the end face of the anti-loosening nut is provided with an anti-rotation tooth that fits against the end of the limiting post, and the end of the limiting post is provided with a tooth structure that meshes with the anti-rotation tooth.

[0012] Furthermore, two main fastening nuts are provided.

[0013] Furthermore, the lock nut is a hexagonal nut.

[0014] Furthermore, the anti-loosening nut is externally fitted with a hexagonal anti-slip component.

[0015] Furthermore, an elastic element is provided between the anti-loosening nut and the hexagonal anti-slip component. The elastic element is used to absorb vibration and keep the anti-loosening nut and the hexagonal anti-slip component in a tight abutment state at all times.

[0016] A microwave transmission device includes at least two waveguides and a plurality of bolt assemblies, wherein the ends of the waveguides are provided with flanges, and adjacent flanges are connected by the bolt assemblies.

[0017] The beneficial effects of this invention are: The bolt assembly and microwave transmission device obtained by the present invention, as designed above, are used in such cases. After the bolt shank is inserted into the connected component, the main fastening nut is screwed onto the threaded rod. The elastic rubber ring set in the annular sealing groove increases the friction between the bolt and the connected component, achieving initial anti-loosening. Then, the fastening rod of the anti-loosening fastener is inserted through the anti-loosening hole and extends to the outer end of the bolt head, and is locked by the anti-loosening nut. When the anti-loosening nut is tightened, a strong axial tensile force is applied to the fastening rod. This axial tensile force is transmitted to the fastening head, ultimately creating a reverse locking interaction between the fastening head and the main fastening nut. This interaction manifests as a pressure on the main fastening nut or a tension on the threaded rod, thereby effectively counteracting the tendency of the main fastening nut to loosen due to vibration, achieving an extremely reliable anti-loosening effect. This application applies additional force to the main fastening system through an independent anti-loosening system, forming a dual anti-loosening mechanism, which is significantly better than the traditional method that relies solely on thread friction. Furthermore, the main fastening system and the anti-loosening system are independent of each other. Even if the anti-loosening system fails under extreme conditions, the main fastening system can still maintain a basic connection, ensuring high safety. All anti-loosening components are integrated into the bolt body, eliminating the need for additional complex accessories, resulting in a simple structure and convenient installation. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the bolt assembly provided in Embodiment 1 of the present invention; Figure 2 This is an exploded view of the bolt assembly provided in Embodiment 1 of the present invention; Figure 3 This is a cross-sectional view of the bolt assembly provided in Embodiment 1 of the present invention; Figure 4 This is a schematic diagram of the bolt assembly provided in Embodiment 2 of the present invention; Figure 5 This is an exploded view of the bolt assembly provided in Embodiment 2 of the present invention; Figure 6 This is a cross-sectional view of the bolt assembly provided in Embodiment 2 of the present invention.

[0020] Icons: 1- Bolt assembly; 11-Main fastening nut; 12-Bolt rod; 121-Threaded rod; 122-Bolt head; 1221-Annular sealing groove; 123-Anti-loosening hole; 13-Anti-loosening nut; 131-Anti-rotation teeth; 14-Anti-loosening fastener; 141-Fastening head; 142-Fastening rod; 15-Limiting post; 151-Tooth structure; 16-Hexagonal anti-slip component. Detailed Implementation

[0021] Please refer to Figures 1-6 This embodiment provides a bolt assembly 1 for a waveguide, which includes a bolt rod 12, an anti-loosening fastener 14, a main fastening nut 11, and an anti-loosening nut 13. The bolt rod 12 and the main fastening nut 11 are similar to existing structures and are mainly used to connect two components to be connected. The anti-loosening nut 13 is located on the outer side of the head of the bolt rod 12 and is used to connect with the anti-loosening fastener 14. It generates a strong axial tensile force on the fastening rod 142, so that the fastening head 141 and the main fastening nut 11 form an anti-loosening lock, thereby achieving the anti-loosening effect.

[0022] The aforementioned main fastening nut 11 can be a standard component. The bolt shank 12 includes a lead screw 121 and a bolt head 122 at one end of the lead screw 121. The main fastening nut 11 is threaded into the lead screw 121 and is used to provide clamping force to the connected component (such as a waveguide flange) during installation. By tightening the main fastening nut 11, the bolt shank 12 can be axially preloaded, causing the bolt head 122 to press against the flange, thus achieving flange connection. The bolt shank 12 has an anti-loosening hole 123 extending through it along its axial direction, that is, the anti-loosening hole 123 passes through the lead screw 121 and the bolt head 122. The anti-loosening hole 123 is used to prevent the fastener 14 from being inserted. The anti-loosening fastener 14 includes an integrally connected fastening head 141 and fastening rod 142. The fastening head 141 is disposed at the end of the screw 121 away from the bolt head 122. The fastening rod 142 is disposed to pass through the anti-loosening hole 123 and, after passing through the bolt rod 12, form a force-bearing structure that penetrates the bolt rod 12.

[0023] The lock nut 13 is threadedly connected to the fastening rod 142 extending beyond the bolt head 122. As a force-applying component, it can be a hexagonal nut or have an external hexagonal anti-slip element 16 for easy tool tightening. When the lock nut 13 is tightened, a strong axial tensile force is applied to the fastening rod 142. This force is transmitted through the fastening rod 142 to the fastening head 141, ultimately creating a reverse locking interaction between the fastening head 141 and the main fastening nut 11. This interaction manifests as a tightening of the main fastening nut 11 or a tensioning of the lead screw 121, effectively counteracting the tendency of the main fastening nut 11 to loosen due to vibration, achieving an extremely reliable anti-loosening effect. At the same time, the tension of the fastening rod 142 reacts to the bolt head 122, keeping the bolt rod 12 in a taut state and forming a two-way locking structure. The threaded pairs of the main fastening nut 11 and the lead screw 121, and the anti-loosening nut 13 and the fastening rod 142, all generate large friction due to the preload, which can effectively prevent the threads from sliding even under vibration conditions, thus achieving long-term anti-loosening.

[0024] In addition, the clamping surface of the bolt head 122 is provided with an annular sealing groove 1221 to prevent the bolt shank from rotating. An elastic rubber ring (not shown in the figure) with a high coefficient of friction is provided in the annular sealing groove 1221. After the bolt is tightened, a large frictional force is generated between the elastic rubber ring and the flange surface and the bolt head 122, which can effectively suppress the rotation of the bolt assembly and further prevent relative slippage between the threads under vibration conditions, thus achieving long-term anti-loosening.

[0025] Furthermore, to enhance the stability of the initial clamping, two main fastening nuts 11 can be provided. After the two nuts are tightened together, they form a basic effect of double-nut anti-loosening, further reducing the risk of initial loosening.

[0026] The technical solution of the bolt assembly 1 of this application is further described in detail below with several specific embodiments: Example 1:

[0027] Reference Figures 1-3 This embodiment provides a bolt assembly 1. The bolt shank 12 includes an integrally connected lead screw 121 and bolt head 122. The clamping surface of the bolt head 122 is provided with an annular sealing groove 1221. The bolt shank 12 is provided with an anti-loosening hole 123 along the axial direction. The anti-loosening hole 123 is a cylindrical hole that passes through the center of the lead screw 121 and the bolt head 122.

[0028] The fastening head 141 is a cylindrical tube with one end open, and the fastening rod 142 is connected to the inside of the cylindrical tube with one end closed. When the fastening rod 142 passes through the anti-loosening hole 123 and the anti-loosening nut 13 is tightened, the cylindrical tube is sleeved on the outside of the screw 121 and pressed against the main fastening nut 11.

[0029] In practice, first, tighten the main fastening nut 11 to the normal torque to press the flange. Then, place the cylindrical sleeve outside the threaded rod 121, and pass the fastening rod 142 through the anti-loosening hole 123. Finally, tighten the anti-loosening nut 13. When tightening the anti-loosening nut 13, the fastening rod 142 is pulled, causing the entire cylindrical sleeve to move upward (towards the bolt head 122), so that the open end of the cylindrical sleeve presses tightly against the main fastening nut 11. This strong pressure greatly increases the friction between the main fastening nut 11 and the flange contact surface, as well as between the main fastening nut 11 and the thread of the threaded rod 121, thus achieving efficient mechanical anti-loosening. This solution has a symmetrical structure, uniform stress distribution, and is easy to install. Example 2:

[0030] Please refer to Figures 4-6 This embodiment provides another bolt assembly 1, which differs from Embodiment 1 in that the anti-loosening hole 123 is a wedge-shaped hole. The wedge-shaped hole penetrates the lead screw 121 radially, and the cross-sectional area of ​​the wedge-shaped hole gradually decreases from the end of the lead screw 121 towards the bolt head 122. Correspondingly, the fastening head 141 is a wedge-shaped block, and the fastening rod 142 is connected to the end of the wedge-shaped block with the smaller cross-sectional area. The wedge-shaped block can be wedged into the wedge-shaped hole. When the fastening rod 142 passes through the anti-loosening hole 123 and the anti-loosening nut 13 is tightened, the wedge-shaped block is wedged into the wedge-shaped hole, thereby tensioning the lead screw 121.

[0031] In specific operation, first tighten the main fastening nut 11, then pass the wedge block and fastening rod 142 through the anti-loosening hole 123 from the bottom, and finally tighten the anti-loosening nut 13. When tightening the anti-loosening nut 13, it will pull the wedge block to move towards the direction of the smaller hole diameter, thereby wedging the wedge block tightly into the wedge hole. This wedging action will generate a radial force, tensioning the lead screw 121 outward. The tensioned lead screw 121 will generate a huge clamping force on the thread of the main fastening nut 11, and at the same time, the lead screw 121 will slightly expand radially, making the diameter of the end of the bolt rod 12 away from the bolt head 122 larger than the diameter of the end of the bolt head 122, so that the main fastening nut 11 always maintains a tendency to rotate towards the bolt head 122, thereby achieving long-term anti-loosening. Through the combined action of these two mechanisms, a stronger anti-loosening effect than Scheme 1 is achieved, which is particularly suitable for long-term anti-loosening in high-intensity vibration environments. Example 3:

[0032] To further prevent the anti-loosening nut 13 from loosening itself, a limiting post 15 is provided at the center of the end face of the bolt head 122 away from the lead screw 121. The end face of the anti-loosening nut 13 is provided with an anti-rotation tooth 131 that fits against the end of the limiting post 15. The end of the limiting post 15 is provided with a tooth structure 151 that meshes with the anti-rotation tooth 131. When the anti-loosening nut 13 is tightened to the preset position, the anti-rotation tooth 131 and the tooth structure 151 of the limiting post 15 mesh with each other to form a mechanical interlock, restricting the rotation of the anti-loosening nut 13 through the interlocking of the teeth.

[0033] Furthermore, a hexagonal anti-slip element 16 is fitted around the anti-loosening nut 13, and a spring (not shown in the figure) is provided between the anti-loosening nut 13 and the hexagonal anti-slip element 16. The spring is tensioned between the contact surfaces of the anti-loosening nut 13 and the hexagonal anti-slip element 16 to absorb vibration and keep the anti-loosening nut 13 and the hexagonal anti-slip element 16 in a tight state at all times, forming a secondary anti-loosening mechanism. This effectively prevents the anti-loosening nut 13 from spontaneously disengaging under extreme vibration and ensures the long-term stability of the tension of the fastening rod 142.

[0034] Specifically, the anti-rotation tooth 131 and the tooth structure 151 are helical teeth in the same direction, and their inclination direction is opposite to the tightening direction of the anti-loosening nut 13, that is, the anti-loosening nut 13 is blocked when it is screwed out in the opposite direction. Example 4:

[0035] This embodiment also provides a microwave transmission device, which includes multiple waveguides connected end-to-end, with flanges provided between adjacent ends, and adjacent flanges connected by the bolt assembly 1 described above. This device benefits from the excellent anti-loosening performance of the bolt assembly 1, resulting in higher reliability and a longer maintenance cycle.

[0036] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the invention by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the invention should be included within the scope of protection of the invention.

Claims

1. A bolt assembly for a waveguide, characterized in that, Includes bolt rods, anti-loosening fasteners, main fastening nuts, and anti-loosening nuts; The bolt rod includes an integrally connected lead screw and bolt head. The clamping surface of the bolt head is provided with an annular sealing groove, and an elastic rubber ring is provided in the annular sealing groove. The main fastening nut is threaded with the lead screw and is used to provide an initial clamping force to the connected parts; The anti-loosening fastener includes a fastening head and a fastening rod. The bolt rod has an anti-loosening hole extending through it along its axial direction. The fastening head engages with the end of the screw away from the bolt head, and the fastening rod passes through the anti-loosening hole. The anti-loosening nut is threadedly connected to the fastening rod portion extending beyond the bolt head. Tightening the anti-loosening nut can cause the fastening rod to be under tension, thereby forming an anti-loosening lock through the interaction between the fastening head and the main fastening nut.

2. A bolt assembly for a waveguide according to claim 1, characterized in that, The anti-loosening hole is a cylindrical hole, the fastening head is a cylindrical tube with one end open, and the fastening rod is connected to the inside of the cylindrical tube and closes one end; when the fastening rod passes through the anti-loosening hole and the anti-loosening nut is tightened, the cylindrical tube is sleeved on the outside of the lead screw and pressed against the main fastening nut.

3. A bolt assembly for a waveguide according to claim 1, characterized in that, The anti-loosening hole is a wedge-shaped hole that penetrates the lead screw radially, and the cross-sectional area of ​​the wedge-shaped hole gradually decreases from the end of the lead screw toward the bolt head.

4. A bolt assembly for a waveguide according to claim 3, characterized in that, The fastening head is a wedge-shaped block, and the fastening rod is connected to the small end of the wedge-shaped block. The wedge-shaped block can be wedged into the wedge-shaped hole. When the fastening rod passes through the anti-loosening hole and the anti-loosening nut is tightened, the wedge-shaped block is wedged into the wedge-shaped hole, thereby tensioning the lead screw.

5. A bolt assembly for a waveguide according to any one of claims 1-4, characterized in that, A limiting post is provided at the center of the end face of the bolt head away from the lead screw; the end face of the anti-loosening nut is provided with an anti-rotation tooth that fits against the end of the limiting post, and the end of the limiting post is provided with a tooth structure that meshes with the anti-rotation tooth.

6. A bolt assembly for a waveguide according to claim 1, characterized in that, The anti-loosening nut is fitted with a hexagonal anti-slip component.

7. A bolt assembly for a waveguide according to claim 6, characterized in that, An elastic element is provided between the anti-loosening nut and the hexagonal anti-slip component. The elastic element is used to absorb vibration and keep the anti-loosening nut and the hexagonal anti-slip component in a tight abutment state at all times.

8. A microwave transmission device, characterized in that, The microwave transmission device includes at least two waveguides and a plurality of bolt assemblies as described in any one of claims 1-7, wherein the ends of the waveguides are provided with flanges, and adjacent flanges are connected by the bolt assemblies.

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