Four-channel coaxial rotary joint

Abstract

The invention relates to the technical field of rotary joints, in particular to a four-channel coaxial rotary joint which comprises a fixed shell, channel joints, a stator fixing part, an end face sealing cover, a main path assembly, a rotary wiring structure and a hole-shaped Glyd ring. The number of the channel joints can be flexibly configured according to requirements, basic three channels are expanded to nine independent channels at most, and the use applicability of the rotary joint is improved; the joint is subjected to continuous full-angle rotation through the rotary wiring structure, and the signal quality is not affected; the channel joint is made of alloy and composite materials capable of maintaining mechanical strength and elasticity at the extremely low temperature, and the stability of the rotary joint in the extremely low temperature environment is improved. External water vapor, dust and other impurities are effectively prevented from entering the rotary joint through the hole-shaped Glyd ring, and influence on signal transmission is avoided; according to the structure of the grid sheet, by optimizing the geometrical shape and the material distribution, the compressive strength is improved, meanwhile, the contact area between parts is reduced, and the friction force is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of rotary joints, and more specifically, to a four-channel coaxial rotary joint. Background Art

[0002] A four-channel coaxial rotary joint is a device that can achieve simultaneous docking and signal transmission of four signal lines and allows relative rotation between components. Based on the principle of coaxial transmission lines, the four-channel coaxial rotary joint uses the electromagnetic field between the inner conductor and the outer conductor to transmit signals. During rotation, through special structural designs such as slip rings, brushes, or other coupling methods, the electrical connections between the inner and outer conductors of the four channels are always kept in good condition, enabling signals to be stably transmitted between the two rotating components while avoiding signal leakage, attenuation, and interference.

[0003] However, most current rotary joints have limited bandwidth, usually unable to reach the 8 GHz frequency band, and have weak multi-channel transmission capabilities, only providing 1 to 2 channels, resulting in low applicability of the joints; existing rotary joints generally lack good waterproof characteristics, with insufficient reliability in humid or underwater environments and poor joint performance; when the temperature drops to -45 °C, many existing rotary joints will experience signal loss problems, have poor low-temperature resistance, affecting normal operation and the stability of signal transmission; most traditional rotary joints are prone to wear and failure after long-term use, with a short service life. Summary of the Invention

[0004] In view of the problems in the prior art, the present invention provides a four-channel coaxial rotary joint.

[0005] The technical solution adopted by the present invention to solve its technical problems is: a four-channel coaxial rotary joint, including a fixed housing, a plurality of channel joints arranged inside the fixed housing, an end face cover fixedly connected to the end of the fixed housing, a stator fixing member fixedly connected to the end face cover, a main circuit assembly arranged on the end face cover, a rotary wiring structure arranged on the fixed housing, and a hole-shaped Grease Seal arranged between the fixed housing and the rotary wiring structure;

[0006] The channel joint includes a channel stator and a channel rotor. A channel stator of one channel joint is fixedly connected to the stator fixing member. A channel rotor is rotatably connected inside the channel stator. A central through-wire tube is fixedly connected inside the channel rotor. The central through-wire tube penetrates the channel stator. A grid piece is fixedly connected to the channel stator. The central through-wire tube is rotatably connected to the grid piece. A channel bearing is installed between the channel rotor and the channel stator. A first bearing fixing member is fixedly connected to the stator housing of the channel stator. The first bearing fixing member is buckled with the channel bearing. A rotor cover plate is fixedly connected to the channel rotor. An insertion block on the central through-wire tube of one channel joint is inserted into a jack on the rotor cover plate of another channel joint. The stator housing of the channel stator of one channel joint is inserted into the first bearing fixing member of another channel joint. A stator cover plate is fixedly connected to the channel stator.

[0007] Specifically, the main path assembly includes a joint and a pin fixing member. Four joints are fixedly connected to the end face cover. Among them, three joints are distributed in a circular array about the axis of the end face cover, and another joint is arranged on the axis of the end face cover.

[0008] Specifically, a pin fixing member is fixedly connected inside the joint located in the center. A main path pin is fixedly connected inside the pin fixing member. A pin rotating sleeve is rotatably connected inside the central through-wire tube of the lowermost channel joint. The main path pin is rotatably connected to the pin rotating sleeve. A second insulator is fixedly connected to the pin rotating sleeve.

[0009] Specifically, the rotary wiring structure includes a rotary shell and four connectors fixedly connected to the rotary shell. The rotary shell is rotatably connected to the top end of the fixed outer shell. Four anti-rotation screws are threadedly connected to the rotor cover plate of the uppermost channel joint. A driving disk is inserted on the four anti-rotation screws. A second bearing fixing member is fixedly connected to the driving disk. A wiring bearing is installed between the second bearing fixing member and the fixed outer shell. A bearing pressing plate is fixedly connected to the top end of the fixed outer shell. The bearing pressing plate is buckled with the wiring bearing. The rotary shell is fixedly connected to the second bearing fixing member.

[0010] Specifically, the hole-shaped Grease Seal Ring includes a sealing ring and an O-ring. The sealing ring is installed on the fixed outer shell. The rotary shell is rotatably connected to the sealing ring. The O-ring is fixedly connected to the sealing ring. The O-ring abuts against the fixed outer shell.

[0011] Specifically, the height of the channel joint is not greater than 20 mm. The axes of multiple spliced channel joints are on a straight line. The length of the fixed outer shell is greater than the length of multiple spliced channel joints. At most 9 channel joints can be spliced inside the fixed outer shell.

[0012] Specifically, the sealing ring is made of polytetrafluoroethylene and bronze materials, and the O-ring is made of hydrogenated nitrile materials.

[0013] Specifically, both the channel stator and the channel rotor are made of alloy and composite materials, and the fixed housing and the rotating housing are processed by sandblasting and anodic oxidation.

[0014] Specifically, the grid plate is integrally in a cylindrical structure, the upper part of the grid plate is an annular flange, and multiple slots are axially provided in the lower part.

[0015] Specifically, the grid plate is made of high-strength and corrosion-resistant alloy materials, and the surface of the grid plate is gold-plated.

[0016] The beneficial effects of the present invention are as follows:

[0017] (1) For a four-channel coaxial rotary joint of the present invention, a channel joint is provided inside the fixed housing. The number of channel joints can be flexibly configured according to requirements, expanding from the basic three channels to a maximum of nine independent channels, improving the applicability of the rotary joint.

[0018] (2) For a four-channel coaxial rotary joint of the present invention, a main path assembly is provided on the fixed housing, and a rotary wiring structure is provided on the fixed housing. Through the rotary wiring structure, the joint can be continuously rotated through a full angle without affecting the signal quality.

[0019] (3) For a four-channel coaxial rotary joint of the present invention, the channel joint selects special alloys and composite materials that can maintain mechanical strength and elasticity at extremely low temperatures, improving the stability of the rotary joint in extreme low-temperature environments.

[0020] (4) For a four-channel coaxial rotary joint of the present invention, a hole-shaped Gleitring is provided between the rotating housing and the fixed housing. Through the hole-shaped Gleitring, external moisture, dust and other impurities can be effectively prevented from entering the inside of the rotary joint, avoiding affecting signal transmission.

[0021] (5) For a four-channel coaxial rotary joint of the present invention, the structure of the grid plate optimizes the geometric shape and material distribution, not only improving the compressive strength, but also reducing the contact area between components, thereby reducing the friction force. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention will be further described below with reference to the drawings and embodiments.

[0023] Figure 1 It is a schematic diagram of the overall structure of a preferred embodiment of a four-channel coaxial rotary joint provided by the present invention;

[0024] Figure 2Schematic diagram of the connection structure between the fixed housing and the channel joint of the present invention;

[0025] Figure 3 is Figure 2 Enlarged schematic diagram of the structure of part A shown;

[0026] Figure 4 Schematic diagram of the connection structure between the channel stator and the first bearing fixing part of the present invention;

[0027] Figure 5 Schematic diagram of the connection structure between the channel rotor and the rotor cover plate of the present invention;

[0028] Figure 6 Schematic diagram of the connection structure between the central pipe for passing through wires and the grid pieces of the present invention.

[0029] In the figure: 1. Fixed housing; 2. Channel joint; 201. Channel stator; 202. Channel rotor; 203. Central pipe for passing through wires; 204. Grid pieces; 205. Stator cover plate; 206. First bearing fixing part; 207. Channel bearing; 208. Rotor cover plate; 3. Stator fixing part; 4. End face cover; 5. Main path assembly; 501. Joint; 502. Pin fixing part; 503. Main path pin; 504. Pin rotating sleeve; 505. No. 2 insulator; 6. Rotating wiring structure; 601. Rotating shell; 602. Connector; 603. Anti-rotation screw; 604. Driving disc; 605. Second bearing fixing part; 606. Bearing pressing plate; 607. Wiring bearing; 7. Hole-shaped Greble ring; 701. Sealing ring; 702. O-ring. Detailed implementation manners

[0030] In order to make the technical means, creative features, achieved purposes and effects of the present invention easy to understand, the present invention will be further described below in conjunction with specific implementation manners.

[0031] As Figures 1-6 shown, a four-channel coaxial rotating joint of the present invention includes a fixed housing 1, a plurality of channel joints 2 arranged inside the fixed housing 1, an end face cover 4 fixedly connected to the end of the fixed housing 1, a stator fixing part 3 fixedly connected to the end face cover 4, a main path assembly 5 arranged on the end face cover 4, a rotating wiring structure 6 arranged on the fixed housing 1, and a hole-shaped Greble ring 7 arranged between the fixed housing 1 and the rotating wiring structure 6;

[0032] The channel joint 2 includes a channel stator 201 and a channel rotor 202. A channel stator 201 of a channel joint 2 is fixedly connected to the stator fixing member 3. A channel rotor 202 is rotatably connected inside the channel stator 201. A central wire passing tube 203 is fixedly connected inside the channel rotor 202. The central wire passing tube 203 penetrates the channel stator 201. A grid piece 204 is fixedly connected to the channel stator 201. The central wire passing tube 203 is rotatably connected to the grid piece 204. A channel bearing 207 is installed between the channel rotor 202 and the channel stator 201. A first bearing fixing member 206 is fixedly connected to the stator outer shell of the channel stator 201. The first bearing fixing member 206 is buckled with the channel bearing 207. A rotor cover plate 208 is fixedly connected to the channel rotor 202. The insertion block on the central wire passing tube 203 of one channel joint 2 is inserted into the insertion hole on the rotor cover plate 208 of another channel joint 2. The stator outer shell of the channel stator 201 of one channel joint 2 is inserted into the first bearing fixing member 206 of another channel joint 2. A stator cover plate 205 is fixedly connected to the channel stator 201. The height of the channel joint 2 is not greater than 20 mm. The axes of multiple spliced channel joints 2 are on the same straight line. The length of the fixed outer shell 1 is greater than the length of multiple spliced channel joints 2. At most 9 channel joints 2 can be spliced inside the fixed outer shell 1. Multiple channel joints 2 are synchronously rotated by inserting the insertion block on the central wire passing tube 203 into the insertion hole on the rotor cover plate 208 and inserting the stator outer shell of the channel stator 201 into the first bearing fixing member 206, enabling the entire rotary joint to stably perform relative rotational motion. The single-channel joint and the two-channel joint are independent wholes respectively. The number of channels can be directly stacked according to needs, thereby realizing ultra-wideband operation from DC to 8 GHz and having a powerful multi-channel transmission capacity. The number of channel joints 2 can be flexibly configured according to requirements, expanding from the basic three channels to a maximum of nine independent channels, improving the applicability of the rotary joint.

[0033] Specifically, the main path assembly 5 includes a joint 501 and a pin fixing member 502. Four joints 501 are fixedly connected to the end face cover 4. Three of the joints 501 are circumferentially arranged around the axis of the end face cover 4, and another joint 501 is arranged on the axis of the end face cover 4. A pin fixing member 502 is fixedly connected inside the central joint 501. A main path pin 503 is fixedly connected inside the pin fixing member 502. A pin rotating sleeve 504 is rotatably connected inside the central wire passing tube 203 of the lowermost channel joint 2. The main path pin 503 is rotatably connected to the pin rotating sleeve 504. A second insulator 505 is fixedly connected to the pin rotating sleeve 504.

[0034] The rotating wiring structure 6 includes a rotating housing 601 and four connectors 602 fixedly connected to the rotating housing 601. The top end of the fixed housing 1 is rotatably connected to the rotating housing 601. Four anti-rotation screws 603 are threadedly connected to the rotor cover plate 208 of the topmost channel joint 2. A drive disk 604 is inserted on the four anti-rotation screws 603. A second bearing fixing member 605 is fixedly connected to the drive disk 604. A wiring bearing 607 is installed between the second bearing fixing member 605 and the fixed housing 1. A bearing pressing plate 606 is fixedly connected to the top end of the fixed housing 1. The bearing pressing plate 606 is buckled with the wiring bearing 607. The rotating housing 601 is fixedly connected to the second bearing fixing member 605. Since there are four connectors 501 on the end face cover 4, three of which are distributed in a circumferential array and one is located at the axis center, according to the actual signal transmission requirements, the corresponding equipment is connected to the appropriate connector 501. At the same time, the corresponding lines of the external equipment are connected to the four connectors 602 on the rotating housing 601 to ensure a firm connection and prepare for signal transmission. The rotating joint is mostly installed on the turntable. When it is necessary for the rotating joint to realize the relative rotation between components, when the external power source drives the turntable to rotate, it drives the rotor cover plate 208 of the topmost channel joint 2 to rotate. The four anti-rotation screws 603 threadedly connected to the rotor cover plate 208 will drive the drive disk 604 to rotate synchronously. The second bearing fixing member 605 fixedly connected to the drive disk 604 rotates accordingly, and then drives the rotating housing 601 connected to the second bearing fixing member 605 to rotate. In this process, the wiring bearing 607 at the top end of the fixed housing 1 plays a role in supporting and reducing friction, ensuring the smooth rotation of the rotating housing 601. The joint is continuously rotated through 360 degrees by the rotating wiring structure 6 without affecting the signal quality.

[0035] Specifically, the orifice Gland packing 7 includes a sealing ring 701 and an O-ring 702. The sealing ring 701 is installed on the fixed housing 1. The rotating housing 601 is rotatably connected to the sealing ring 701. The O-ring 702 is fixedly connected to the sealing ring 701. The O-ring 702 abuts against the fixed housing 1. The sealing ring 701 is made of polytetrafluoroethylene and bronze materials. The O-ring 702 is made of hydrogenated nitrile butadiene material. The sealing ring 701 of the orifice Gland packing 7 is made of polytetrafluoroethylene and bronze materials, and the O-ring 702 is made of hydrogenated nitrile butadiene material. They are closely matched to effectively prevent external moisture, dust and other impurities from entering the inside of the rotating joint and avoid affecting signal transmission.

[0036] Specifically, both the channel stator 201 and the channel rotor 202 are made of alloy and composite materials. The fixed housing 1 and the rotating housing 601 are processed by sandblasting and anodic oxidation. The grid plate 204 is integrally in a cylindrical structure. The upper part of the grid plate 204 is an annular flange and the lower part is axially provided with a plurality of slots. The grid plate 204 is made of a high-strength and corrosion-resistant alloy material and its surface is gold-plated. Special alloys and composite materials that can maintain mechanical strength and elasticity at extremely low temperatures are selected, improving the stability of the rotary joint in an extremely low temperature environment. During the operation of the rotary joint, signals are input from the main path pin 503 of the main path assembly 5. The main path pin 503 is rotatably connected to the pin rotating sleeve 504 in the central wire tube 203 at the center of the lowermost channel joint 2. The second insulator 505 on the pin rotating sleeve 504 plays an insulating and protective role to ensure stable signal transmission. The signals pass through the central wire tube 203 and are transmitted through the cooperation of each channel joint 2, and finally output to external equipment from the connector 602 of the rotary wiring structure 6. During this period, it is necessary to monitor the signal transmission situation in real time to observe whether there are problems such as signal leakage, attenuation or interference. Since the grid plate 204 on the channel stator 201 is made of a high-strength and corrosion-resistant alloy material and its surface is gold-plated, this design helps to reduce signal loss and improve the stability and reliability of signal transmission. At the same time, the structure of the grid plate 204 optimizes the geometric shape and material distribution, not only improving the compressive strength, but also reducing the contact area between components, thereby reducing the friction force.

[0037] When the present invention is in use, first, since there are four connectors 501 on the end face cover 4, three of which are distributed in a circumferential array and one is located at the axis center. According to the actual signal transmission requirements, the corresponding equipment is connected to the appropriate connector 501. At the same time, the corresponding lines of the external equipment are connected to the four connectors 602 on the rotating housing 601 to ensure a firm connection and prepare for signal transmission.

[0038] Then, the rotating joints are mostly installed on the turntable. When it is necessary to rotate the joints to achieve relative rotation between components, when the external power source drives the turntable to rotate, it drives the rotor cover plate 208 of the topmost channel joint 2 to rotate. The four anti-rotation screws 603 threadedly connected to the rotor cover plate 208 will drive the drive disk 604 to rotate synchronously. The second bearing fixing member 605 fixedly connected to the drive disk 604 will rotate accordingly, and then drive the rotating shell 601 connected to the second bearing fixing member 605 to rotate. During this process, the wiring bearing 607 at the top of the fixed housing 1 plays a role in supporting and reducing friction, ensuring the stable rotation of the rotating shell 601. Through the rotating wiring structure 6, the joint can be continuously rotated through a full angle without affecting the signal quality. At the same time, between multiple channel joints 2, they are inserted and connected through the insertion blocks on the central wire tube 203 and the insertion holes on the rotor cover plate 208, and the stator housing of the channel stator 201 is inserted and connected to the first bearing fixing member 206, so as to achieve synchronous rotation, enabling the entire rotating joint to stably perform relative rotational motion. The single-channel joint and the two-channel joint are independent wholes respectively, and the number of channels can be directly stacked according to needs, thereby realizing ultra-wideband operation from DC to 8 GHz and having a powerful multi-channel transmission ability. The number of channel joints 2 can be flexibly configured according to requirements, expanding from the basic three channels to a maximum of nine independent channels, improving the applicability of the rotating joint;

[0039] Finally, during the operation of the rotating joint, the signal is input from the main road pin 503 of the main road assembly 5. The main road pin 503 is rotationally connected to the pin rotating sleeve 504 located in the central wire tube 203 of the bottommost channel joint 2. The second insulator 505 on the pin rotating sleeve 504 plays an insulating and protecting role to ensure stable signal transmission. The signal passes through the central wire tube 203 and is transmitted through the cooperation of each channel joint 2, and finally is output from the connector 602 of the rotating wiring structure 6 to the external device. During this period, it is necessary to monitor the signal transmission situation in real time to observe whether there are problems such as signal leakage, attenuation or interference. Since the grid pieces 204 on the channel stator 201 are made of high-strength, corrosion-resistant alloy materials and are surface gold-plated, this design helps to reduce signal loss and improve the stability and reliability of signal transmission. At the same time, the structure of the grid pieces 204 improves the compressive strength and reduces the contact area between components by optimizing the geometric shape and material distribution, thereby reducing the friction force. The sealing ring 701 of the orifice-shaped Greble ring 7 is made of polytetrafluoroethylene and bronze materials, and the O-ring 702 is made of hydrogenated nitrile materials. They are closely matched to effectively prevent external moisture, dust and other impurities from entering the inside of the rotating joint and avoid affecting signal transmission. The channel stator 201 and the channel rotor 202 are both made of alloy and composite materials. The fixed housing 1 and the rotating shell 601 are processed by sandblasting and anodic oxidation, and special alloys and composite materials that can maintain mechanical strength and elasticity at extremely low temperatures are selected to improve the stability of the rotating joint in extreme low-temperature environments.

[0040] It is obvious to those skilled in the art that the present invention is not limited to the details of the above-described exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, in any aspect, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Accordingly, all changes that fall within the meaning and scope of the equivalent elements of the claims are intended to be embraced within the present invention. Any reference signs in the claims should not be construed as limiting the claims involved.

[0041] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A four-channel coaxial rotary joint, characterized in that: The invention comprises a fixed housing (1), a plurality of channel joints (2) arranged inside the fixed housing (1), an end face cover (4) fixedly connected to the end of the fixed housing (1), a stator fixing member (3) fixedly connected to the end face cover (4), a main circuit assembly (5) arranged on the end face cover (4), a rotating wiring structure (6) arranged on the fixed housing (1), and a hole-shaped grid ring (7) arranged between the fixed housing (1) and the rotating wiring structure (6); The channel joint (2) comprises a channel stator (201) and a channel rotor (202); the stator fixing member (3) is fixedly connected to a channel stator (201) of the channel joint (2); the channel stator (201) is rotatably connected to the channel rotor (202); the channel rotor (202) is fixedly connected to a central wire tube (203); the central wire tube (203) passes through the channel stator (201); a grid sheet (204) is fixedly connected to the channel stator (201); the central wire tube (203) is rotatably connected to the grid sheet (204); a channel shaft is installed between the channel rotor (202) and the channel stator (201). A bearing (207) is fixedly connected to the stator housing of the channel stator (201), the first bearing fixing member (206) is buckled with the channel bearing (207), a rotor cover plate (208) is fixedly connected to the channel rotor (202), an insert block on the central wire tube (203) of one channel joint (2) is plugged into a plug hole on the rotor cover plate (208) of another channel joint (2), a stator housing of the channel stator (201) of one channel joint (2) is plugged into the first bearing fixing member (206) of another channel joint (2), and a stator cover plate (205) is fixedly connected to the channel stator (201).

2. A four-channel coaxial rotary joint according to claim 1, characterized in that: The main circuit assembly (5) comprises a connector (501) and a pin fixing member (502), and four connectors (501) are fixedly connected to the end face cover (4), wherein three connectors (501) are distributed in a circular array about the axis of the end face cover (4), and another connector (501) is arranged on the axis of the end face cover (4).

3. A four-channel coaxial rotary joint according to claim 2, characterized in that: The connector (501) located in the center is fixedly connected to a pin fixing part (502) inside, and a main circuit pin (503) is fixedly connected to the pin fixing part (502) inside. A pin rotating sleeve (504) is rotatably connected to the central wire passing tube (203) of the channel joint (2) located at the bottom. The main circuit pin (503) is rotatably connected to the pin rotating sleeve (504), and a No. 2 insulator (505) is fixedly connected to the pin rotating sleeve (504).

4. A four-channel coaxial rotary joint according to claim 1, characterized in that: The rotating wiring structure (6) comprises a rotating shell (601) and four connectors (602) fixedly connected to the rotating shell (601); the top end of the fixed shell (1) is rotatably connected to the rotating shell (601); four anti-rotation screws (603) are threadedly connected to the rotor cover plate (208) of the channel joint (2) at the top end; a driving disk (604) is inserted into the four anti-rotation screws (603); a second bearing fixing member (605) is fixedly connected to the driving disk (604); a wiring bearing (607) is installed between the second bearing fixing member (605) and the fixed shell (1); a bearing pressure plate (606) is fixedly connected to the top end of the fixed shell (1); the bearing pressure plate (606) is buckled with the wiring bearing (607); and the rotating shell (601) is fixedly connected to the second bearing fixing member (605).

5. A four-channel coaxial rotary joint according to claim 4, characterized in that: The hole-shaped grid ring (7) comprises a sealing ring (701) and an O-type sealing ring (702); the sealing ring (701) is installed on the fixed housing (1); the rotating housing (601) is rotatably connected to the sealing ring (701); the sealing ring (701) is fixedly connected to the O-type sealing ring (702); and the O-type sealing ring (702) is in contact with the fixed housing (1).

6. A four-channel coaxial rotary joint according to claim 1, characterized in that: The height of the channel joint (2) is no greater than 20 mm, the axes of the plurality of channel joints (2) after being spliced ​​are located in a straight line, the length of the fixed shell (1) is greater than the length of the plurality of channel joints (2) after being spliced, and a maximum of 9 channel joints (2) can be spliced ​​inside the fixed shell (1).

7. A four-channel coaxial rotary joint according to claim 5, characterized in that: The sealing ring (701) is made of polytetrafluoroethylene and bronze materials, and the O-type sealing ring (702) is made of hydrogenated nitrile material.

8. The four-channel coaxial rotary joint according to claim 4, characterized in that: The channel stator (201) and the channel rotor (202) are both made of alloy and composite materials, and the fixed shell (1) and the rotating shell (601) are processed by sandblasting and anodizing.

9. A four-channel coaxial rotary joint according to claim 8, characterized in that: The grid plate (204) is in an overall cylindrical structure; the upper portion of the grid plate (204) is an annular flange and the lower portion is provided with a plurality of slots along the axial direction.

10. A four-channel coaxial rotary joint according to claim 9, characterized in that: The grid plate (204) is made of a high-strength, corrosion-resistant alloy material, and the surface of the grid plate (204) is gold-plated.

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