High-power watertight contact type rotary joint

Abstract

The invention belongs to the technical field of rotary joints, and discloses a high-power watertight contact type rotary joint which comprises a second insulator, one end of the second insulator is provided with a fixedly connected first insulator, the other end of the second insulator is sequentially provided with a third insulator and a fourth insulator, and the fourth insulator is in a step shape. The outer surfaces of the first insulator and the second insulator are sleeved with a first outer conductor, the outer surface of the third insulator is sleeved with a second outer conductor, the top of the first insulator is higher than the first outer conductor, and the four insulators are in a step shape, so that on one hand, a positioning reference is provided, and the assembly precision and efficiency are improved; on the other hand, debris and other impurities of a cable shielding layer are prevented, the inner conductor and the outer conductor are conducted to form a short circuit in a high-power scene, and the top of the first insulator is higher than the first outer conductor, so that the stability and reliability of the rotary joint during high-power transmission are ensured; and on the other hand, external foreign matters are prevented from directly contacting the connection part of the first insulator and the inner conductor, and the protection performance is enhanced.

Description

Technical Field

[0001] This invention belongs to the field of rotary joint technology and relates to a high-power watertight contact rotary joint. Background Technology

[0002] Microwave rotary joints are key mechatronic components in radar, communication, and electromagnetic compatibility testing systems, enabling continuous transmission of radio frequency signals between fixed and rotating ends. They are classified into contact and non-contact types. Contact rotary joints offer advantages such as full-band passability, compact structure, and controllable cost, and are widely used in mechanically scanned radar feed systems, phased array antennas with 360° continuous azimuth rotation, and various electromagnetic anechoic chamber test platforms. They consist of an inner conductor, an outer conductor, an insulating medium, bearings, and sealing components. Electrical continuity during rotation is maintained through elastic or sliding contact. Different application scenarios require different performance indicators such as VSWR, insertion loss, phase stability, power capacity, and rotational life.

[0003] Existing coaxial contact rotary joints struggle to simultaneously meet the requirements of high power load capacity, long-term rotational reliability, and high-level watertightness. In existing structures, the insulating medium is often lower than the outer shell contour, making it prone to signal interruption due to air gap breakdown under high-power conditions. The right-angle transition structure at the connector and cable connection is susceptible to localized electric field concentration under high peak power, inducing arcing and causing device damage. Furthermore, single-stage or simple compression-type sealing designs cannot meet the waterproof and dustproof requirements of continuous inflation and pressure maintenance in harsh outdoor environments. Summary of the Invention

[0004] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a high-power watertight contact rotary joint.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: This invention provides a high-power watertight contact rotary joint, including a second insulator. One end of the second insulator is fixedly connected to a first insulator, and the other end is sequentially provided with a third insulator and a fourth insulator. The fourth insulator is stepped. A first outer conductor is sleeved on the outer surface of the first and second insulators, and a second outer conductor is sleeved on the outer surface of the third insulator. The top of the first insulator is higher than the first outer conductor.

[0006] Furthermore, the first and second insulators are provided with inner conductors, and the inner conductors are provided with fixedly connected sleeves. The sleeves are provided with spring pins, and the outer surface of the spring pins is fitted with elastic elements. The spring pins are fixedly connected to the sleeves through the elastic elements. The third insulator is provided with a socket that is fixedly connected to the spring pins.

[0007] Furthermore, a contact head and a bushing are provided between the third insulator and the first outer conductor, with the bushing fitted onto one end of the contact head and fixedly connected to the first outer conductor.

[0008] Furthermore, a second bushing is provided at the end of the fourth insulator away from the third insulator, and a fastener is fitted on the outer surface of one end of the second bushing, the fastener being fixedly connected to the second outer conductor.

[0009] Furthermore, a first seal is provided between the fastener and the second outer conductor, the inner surface of the second bushing and the fastener is used to connect with the coaxial cable, and a second seal is provided between the fastener and the coaxial cable.

[0010] Furthermore, a bearing is provided between the first outer conductor and the second outer conductor, and a first washer and a second washer are provided between two adjacent bearings. The first washer is fitted on the inner surface of the second outer conductor, and the second washer is fitted on the outer surface of the first outer conductor.

[0011] Furthermore, the bearing is provided with an outer nut at one end and an inner nut at the other end. The outer nut is fixedly connected to the second outer conductor, and the inner nut is fixedly connected to the first outer conductor. A third seal is provided at the end of the inner nut away from the bearing.

[0012] Furthermore, a fourth sealing element is fitted on the outer surface of the end of the first insulator away from the third insulator; a fifth sealing element is provided between the first insulator and the inner conductor.

[0013] Furthermore, a sixth sealing element is provided at the end of the first outer conductor away from the second outer conductor.

[0014] Furthermore, the outer surfaces of the first seal, second seal, third seal, fourth seal, fifth seal, and sixth seal are provided with lubricant.

[0015] Compared with the prior art, the present invention has the following beneficial technical effects: This invention discloses a high-power watertight contact rotary joint. A first insulator is mounted on one end of a second insulator, and a third insulator and a stepped fourth insulator are sequentially mounted on the other end. A first outer conductor is fitted onto the outer surface of the first and second insulators, and a second outer conductor is fitted onto the outer surface of the third insulator. The top of the first insulator is higher than the first outer conductor. This design ensures the stability and reliability of the rotary joint during high-power transmission and prevents external objects from directly contacting the connection between the first insulator and the inner conductor, thus enhancing the overall structural protection. The stepped fourth insulator meets the requirements for high-power testing.

[0016] This invention discloses a high-power watertight contact rotary joint. With the cooperation of the elastic element, the spring pin can always maintain tight elastic contact with the inner wall of the socket, ensuring that the contact resistance is extremely small and stable during high-speed or long-term rotation, significantly reducing signal loss and heat generation, and meeting the requirements of high-power transmission. Secondly, it can effectively compensate for the slight axial and radial offsets generated during assembly or operation, improving the mechanical adaptability and reliability of the joint.

[0017] This invention discloses a high-power watertight contact rotary joint, which has two fourth, third, and first seals. The double sealing structure can effectively improve the reliability of the seal. Even if one seal ages or is damaged due to long-term use, the other seal can still play a sealing role, avoiding the problem of watertight failure and enabling the rotary joint to work stably in long-term marine or humid environments. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a high-power watertight contact rotary joint according to the present invention; Figure 2 This is a schematic diagram of the internal structure of the inner conductor in an embodiment of the present invention; Figure 3 This is a schematic diagram of the sleeve structure in an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of the fourth insulator in an embodiment of the present invention; Figure 5 This is a schematic diagram of the structure of the third sealing ring in an embodiment of the present invention.

[0019] Figure label: 1-Inner conductor; 2-Spring pin; 3-Socket; 4-Sleeve; 5-Contact head; 6-Bushing; 7-First insulator; 8-Second insulator; 9-Third insulator; 10-Fourth insulator; 11-First outer conductor; 12-Second outer conductor; 13-Outer nut; 14-Inner nut; 15-First washer; 16-Second washer; 17-Fastener; 18-Second bushing; 19-Bearing; 20-Sixth seal; 21-Fourth seal; 22-Fifth seal; 23-Third seal; 24-First seal; 25-Elastic element; 26-Second seal. Detailed Implementation

[0020] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0021] Example 1 This invention discloses a high-power watertight contact rotary joint, comprising a second insulator 8, a first insulator 7 fixedly connected to one end of the second insulator 8, and a third insulator 9 and a fourth insulator 10 sequentially disposed at the other end. The fourth insulator 10 is stepped. A first outer conductor 11 is sleeved on the outer surface of the first insulator 7 and the second insulator 8, and a second outer conductor 12 is sleeved on the outer surface of the third insulator 9. The top of the first insulator 7 is higher than the first outer conductor 11. Figure 1 As shown.

[0022] One end of the second insulator 8 is interference-fitted with the first insulator 7, preventing relative displacement during rotation and ensuring signal transmission stability. The other end of the second insulator 8 is sequentially connected to the third insulator 9 and the fourth insulator 10. The fourth insulator 10 has a stepped structure, which serves two purposes: firstly, it provides a positioning reference, allowing for accurate installation during assembly by using the stepped surface of the fourth insulator 10 as a reference, improving assembly precision and efficiency; secondly, it prevents debris and other impurities from causing short circuits between the inner and outer conductors during cable shielding assembly. The first outer conductor 1 is fitted onto the outer surfaces of the first insulator 7 and the second insulator 8, and the second outer conductor 12 is fitted onto the outer surface of the third insulator 9. It should be noted that the top of the first insulator 7 is higher than the first outer conductor 11 to prevent external foreign objects from directly contacting the connection between the first insulator 7 and the inner conductor, enhancing the overall protective performance of the structure.

[0023] An inner conductor 1 is installed inside the first insulator 7 and the second insulator 8. The inner conductor 1 is designed according to the requirements of high-power signal transmission to ensure that the signal will not be attenuated or overheated due to insufficient conductor cross-sectional area during transmission. A sleeve 4 is fixedly connected to one end of the inner conductor 1 near the third insulator 9. A spring needle 2 is installed inside the sleeve 4. The spring needle 2 has good elasticity and conductivity. An elastic element 25 is sleeved on the outer surface of the spring needle 2. In this embodiment, the elastic element 25 is a spring. The spring needle 2 is elastically fixed to the sleeve 4 through the elastic element 25. That is, one end of the elastic element 25 abuts against the stepped surface inside the sleeve 4, and the other end abuts against the protrusion in the middle of the spring needle 2, so that the spring needle 2 has a certain axial expansion and contraction margin in the sleeve 4. The spring needle 2 can effectively compensate for axial displacement, so that the inner conductor 1 and the socket 3 are always in conductive contact. Figure 2 He Ru Figure 3As shown. The third insulator 9 has an internal insertion hole 3, which is adapted to the end of the spring pin 2. The top of the spring pin 2 is inserted into the insertion hole 3 to achieve a fixed connection, effectively compensating for axial displacement caused by component processing errors or assembly gaps during rotation. This ensures that the inner conductor 1 and the insertion hole 3 always maintain reliable conductive contact, providing a guarantee for the continuous transmission of high-power signals. During the rotation of the joint, due to processing errors, there may be a certain axial misalignment between the inner conductor 1 and the third insulator 9. The spring pin 2 can also extend and retract within the sleeve 4 under the action of the elastic element 25, always maintaining contact with the insertion hole 3, ensuring that the signal is not interrupted due to axial displacement.

[0024] A contact head 5 and a bushing 6 are provided between the third insulator 9 and the first outer conductor 11. The contact head 5 is in close contact with the conductive layer on the outer surface of the third insulator 9; the other end is fitted with a bushing 6. The inner wall of the bushing 6 is connected to the contact head 5, while the outer wall is fixed to the end of the first outer conductor 11. The bushing 6 serves two purposes: firstly, it fixes the contact head 5, ensuring its stable position during rotation. During rotation, the contact head 5 may shift, and the bushing 6 ensures that the contact head 5 remains in contact with the conductive layer on the outer surface of the third insulator 9. Secondly, the arc-shaped contact end of the contact head 5 maintains sliding contact with the conductive layer on the outer surface of the third insulator 9, thus connecting the external conductive circuit between the first outer conductor 11 and the second outer conductor 12. Simultaneously, the elastic deformation capability of the contact head 5 compensates for radial gaps, ensuring stable contact resistance and preventing signal loss or overheating due to poor contact.

[0025] like Figure 4As shown, a second bushing 18 is provided at the end of the fourth insulator 10 furthest from the third insulator 9. One end of the second bushing 18 is tightly fitted to the stepped surface of the fourth insulator 10. A fastener 17 is fitted onto the outer surface of the other end of the second bushing 18. The inner wall of the fastener 17 is machined with internal threads, which are adapted to the external threads at the end of the second outer conductor 12. The fastener 17 is fixed to the second outer conductor 12 through a threaded connection. The fastener 17 not only fixes the second bushing 18, but also provides an interface for the connection of the coaxial cable, facilitating on-site installation and disassembly. A first sealing element 24 is provided between the fastener 17 and the second outer conductor 12. The first sealing element 24 is fitted into the sealing groove of the second outer conductor 12. When the fastener 17 is tightened, the first sealing element 24 is compressed, filling the gap between the fastener 17 and the second outer conductor 12, achieving a watertight seal at this location. Meanwhile, the inner surfaces of the second bushing 18 and the fastener 17 are machined with internal threads for threaded connection with the coaxial cable. A second seal 26 is provided between the fastener 17 and the coaxial cable. When tightened, the second seal 26 provides a watertight seal at the connection point with the coaxial cable, preventing rainwater from seeping in through the connection interface. Rainwater is corrosive; if the seal is not tight, it can enter the rotating joint and corrode internal electronic components and conductors, causing equipment damage. The dual sealing design of the first seal 24 and the second seal 26 effectively prevents rainwater and other impurities from entering, ensuring the watertight performance of the rotating joint.

[0026] The first seal 24 is coated with silicone oil, which increases lubrication while ensuring sealing and reducing the resistance of the rotating joint when it starts to rotate. The second seal 26 and the like are similar.

[0027] Two bearings 19 are provided between the first outer conductor 11 and the second outer conductor 12, symmetrically arranged within the annular gap between them. One end of each bearing 19 has an outer nut 13, and the other end has an inner nut 14. A third seal 23 is provided at the end of the inner nut 14 furthest from the bearing 19. Figure 5 As shown, the inner ring of the third seal 23 abuts against the inner wall of the first outer conductor 11, and the outer ring abuts against the inner surface of the second outer conductor 12. A first washer 15 and a second washer 16 are provided between two adjacent bearings 19. The first washer 15 is fitted onto the inner surface of the second outer conductor 12, and its outer diameter matches the inner ring of the bearing 19. The second washer 16 is fitted onto the outer surface of the first outer conductor 11, and its inner diameter matches the outer ring of the bearing 19. The first washer 15 and the second washer 16 separate the two bearings 19, preventing wear caused by friction between the inner and outer rings of the two bearings 19 during rotation. They also adjust the axial clearance of the bearings 19, ensuring smooth rotation, reducing vibration caused by excessive clearance, and improving the stability of signal transmission.

[0028] During rotation, if the two bearings 19 are in direct contact, friction will be generated due to relative motion, accelerating bearing wear and shortening bearing life. The first washer 15 and the second washer 16 separate the two bearings 19, reducing friction and allowing adjustment of the axial clearance of the bearings 19 to ensure smooth rotation. One end of the bearing 19 is provided with an outer nut 13, and the other end is provided with an inner nut 14. The outer nut 13 is tightened onto the second outer conductor 12 by a threaded connection, with its end face abutting against the outer ring of the outer bearing 19, thus axially fixing the outer ring of the bearing 19. The inner nut 14 is adapted to the threaded section on the inner surface of the first outer conductor 11, with its end face abutting against the inner ring of the bearing 19, thus axially fixing the inner ring of the bearing 19. The outer nut 13 and the inner nut 14 fix the two bearings 19 in the annular gap between the first outer conductor 11 and the second outer conductor 12, preventing axial movement of the bearings 19 during rotation. A third seal 23 is provided at the end of the inner nut 14 away from the bearing 19. The inner ring of the third seal 23 abuts against the inner wall of the first outer conductor 11, and the outer ring abuts against the inner surface of the second outer conductor 12, effectively preventing external water, dust, and other impurities from entering the interior of the bearings 19, avoiding wear or jamming caused by impurities, and extending the service life of the bearings 19.

[0029] A fourth sealing element 21 is fitted onto the outer surface of the end of the first insulator 7 furthest from the third insulator 9. The inner side of the fourth sealing element 21 abuts against the outer surface of the first insulator 7, and the outer side abuts against the first outer conductor 11. A fifth sealing element 22 is provided between the first insulator 7 and the inner conductor 1. The fifth sealing element 22 is in close contact with the outer surface of the inner conductor 1 to prevent moisture from seeping into the internal conductive circuit through the gap between the first insulator 7 and the inner conductor 1, thus avoiding short circuits or signal attenuation problems caused by moisture intrusion. Once moisture enters the conductive circuit, it can cause short circuits or signal attenuation problems, affecting the quality of signal transmission.

[0030] A sixth sealing element 20 is provided at the end of the first outer conductor 11 away from the second outer conductor 12. The sixth sealing element 20 is fixed to the end of the first outer conductor 11, and its inner side is in contact with the end face of the first outer conductor 11 to seal the end and prevent external impurities from entering the internal structure of the rotary joint. It should be noted that in this embodiment, there are two fourth sealing elements 21, two third sealing elements 23, and two first sealing elements 24, adopting a double-sealing design. The two fourth sealing elements 21 are arranged at intervals along the axial direction of the first insulator 7, the two third sealing elements 23 are arranged symmetrically along the axial direction of the inner nut 14, and the two first sealing elements 24 are arranged parallel to the axial direction of the fastener 17. The double-sealing structure can effectively improve the reliability of the seal. Even if one sealing element ages or is damaged due to long-term use, the other sealing element can still play a sealing role, avoiding the problem of watertight failure, and enabling the rotary joint to work stably in long-term marine or humid environments.

[0031] This invention discloses a method for using a high-power watertight contact rotary joint: First, the inner conductor 1 is passed through the first insulator 7 and the second insulator 8. A fifth sealing element 22 is installed in the sealing groove between the first insulator 7 and the inner conductor 1, and the fifth sealing element 22 fits tightly against the inner conductor 1. Then, the sleeve 4 is fixed to the end of the inner conductor 1 near the third insulator 9 by an interference fit. The elastic element 25 is then fitted onto the spring pin 2 and inserted into the sleeve 4, completing the assembly of the inner conductive assembly. Next, the first outer conductor 11 is fitted onto the outer surface of the first insulator 7 and the second insulator 8. Two fourth sealing elements 21 are fitted onto the outer surface of the first insulator 7 away from the third insulator 9. Finally, a sixth sealing element 20 is installed at the end of the first outer conductor 11 away from the second outer conductor 12.

[0032] Next, one end of the contact head 5 is inserted into the bushing 6, and the bushing 6 is welded and fixed to the end of the first outer conductor 11. The other end of the contact head 5 is aligned with the conductive layer on the outer surface of the third insulator 9. The third insulator 9 is connected and fixed to the second insulator 8, so that the top end of the spring pin 2 is inserted into the insertion hole 3 inside the third insulator 9 to realize the connection of the inner conductive circuit. The fourth insulator 10 is connected and fixed to the third insulator 9, and the second bushing 18 is installed at the end of the fourth insulator 10. Subsequently, the third seal 23, inner nut 14, bearing 19, first washer 15, second washer 16, second bearing 19 and outer nut 13 are sequentially installed in the annular gap between the first outer conductor 11 and the second outer conductor 12. The inner nut 14 is tightened, and the second outer conductor 12 is fitted onto the outer surface of the third insulator 9. The fastener 17 is fitted onto the second bushing 18 and threadedly connected to the second outer conductor 12 and tightened. After assembly, the installation position of the second seal 26 is reserved in the sealing groove of the fastener 17. It is installed when connected to the coaxial cable to ensure a watertight seal at the connection.

[0033] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

Claims

1. A high-power watertight contact rotary joint, characterized in that: The device includes a second insulator (8), one end of which is fixedly connected to a first insulator (7), and the other end is provided with a third insulator (9) and a fourth insulator (10) in sequence. The fourth insulator (10) is stepped. The outer surfaces of the first insulator (7) and the second insulator (8) are fitted with a first outer conductor (11), and the outer surface of the third insulator (9) is fitted with a second outer conductor (12). The top of the first insulator (7) is higher than the first outer conductor (11).

2. The high-power watertight contact rotary joint according to claim 1, characterized in that: The first insulator (7) and the second insulator (8) are provided with an inner conductor (1), and a sleeve (4) is provided inside the inner conductor (1) for fixed connection. A spring needle (2) is provided inside the sleeve (4), and an elastic element (25) is sleeved on the outer surface of the spring needle (2). The spring needle (2) is fixedly connected to the sleeve (4) through the elastic element (25). The third insulator (9) is provided with a socket (3) for fixed connection with the spring needle (2).

3. The high-power watertight contact rotary joint according to claim 1, characterized in that: A contact head (5) and a bushing (6) are provided between the third insulator (9) and the first outer conductor (11). The bushing (6) is fitted onto one end of the contact head (5) and is fixedly connected to the first outer conductor (11).

4. The high-power watertight contact rotary joint according to claim 3, characterized in that: The fourth insulator (10) is provided with a second bushing (18) at the end away from the third insulator (9). A fastener (17) is fitted on the outer surface of one end of the second bushing (18). The fastener (17) is fixedly connected to the second outer conductor (12).

5. The high-power watertight contact rotary joint according to claim 4, characterized in that: A first seal (24) is provided between the fastener (17) and the second outer conductor (12), the inner surface of the second bushing (18) and the fastener (17) is used to connect with the coaxial cable, and a second seal (26) is provided between the fastener (17) and the coaxial cable.

6. The high-power watertight contact rotary joint according to claim 5, characterized in that: A bearing (19) is provided between the first outer conductor (11) and the second outer conductor (12). A first washer (15) and a second washer (16) are provided between two adjacent bearings (19). The first washer (15) is fitted on the inner surface of the second outer conductor (12), and the second washer (16) is fitted on the outer surface of the first outer conductor (11).

7. The high-power watertight contact rotary joint according to claim 6, characterized in that: The bearing (19) is provided with an outer nut (13) at one end and an inner nut (14) at the other end. The outer nut (13) is fixedly connected to the second outer conductor (12), and the inner nut (14) is fixedly connected to the first outer conductor (11). The inner nut (14) is provided with a third seal (23) at the end away from the bearing (19).

8. The high-power watertight contact rotary joint according to claim 7, characterized in that: A fourth sealing element (21) is fitted on the outer surface of the end of the first insulator (7) away from the third insulator (9); A fifth seal (22) is provided between the first insulator (7) and the inner conductor (1).

9. The high-power watertight contact rotary joint according to claim 8, characterized in that: A sixth seal (20) is provided at the end of the first outer conductor (11) away from the second outer conductor (12).

10. The high-power watertight contact rotary joint according to claim 9, characterized in that: The outer surfaces of the first seal (24), the second seal (26), the third seal (23), the fourth seal (21), the fifth seal (22), and the sixth seal (20) are provided with lubricant.

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