Structure and method for additionally installing tire inflation system on trailer axle

Abstract

The invention discloses a structure and method for additionally installing a tire inflation system on a trailer axle, the structure comprises an axle main body, the axle main body comprises an axle pipe and hubs installed at the two ends of the axle pipe, lubricating hub bearings are arranged between the hubs and the axle pipe, so that the hubs can freely rotate relative to the axle pipe, and lubricating assemblies are arranged at the outer side ends of the hubs. The lubricating assemblies are filled with liquid lubricating oil, the inflating assemblies are further installed on the lubricating assemblies and communicated with tire valve cores, and the inflating assemblies on the hubs are connected with an air source after being connected in parallel, so that real-time air supplementation of the tires is achieved, potential safety hazards caused by tire air shortage are avoided, and meanwhile through a reasonable sealing and exhausting structure, the service life of the tires is prolonged. And the influence of high-temperature gas on a sealing and lubricating system is reduced, so that the driving safety of a vehicle is improved, and the service life of a tire is prolonged.

Description

Technical Field

[0001] This invention relates to the field of special vehicle equipment technology, and more specifically to a structure and method for adding a tire inflation system to a trailer axle. Background Technology

[0002] In the use of special-purpose vehicles, the tire inflation system integrated into the axle is crucial for the vehicle's stable driving safety and performance. Currently, most existing axles do not have a tire inflation system, which brings many shortcomings to the tires on the axle. For example, most equipment relies on external air sources for tire inflation, which is inconvenient to use; the inflation time and location cannot be effectively controlled, which may lead to excessively low tire pressure, affecting tire life and vehicle driving stability. Therefore, there is an urgent need for a tire inflation system that can be integrated into the axle of special-purpose vehicles to solve the problem of timely tire inflation, avoid safety hazards caused by low tire pressure, and, at the same time, enable automatic tire inflation systems on axles that use liquid oil to lubricate bearings, thus making the vehicle safer and extending tire life. Summary of the Invention

[0003] One advantage of this invention is that it provides a structure and method for adding a tire inflation system to a trailer axle. By adding an automatic tire inflation system to the axle hub with a liquid oil-lubricated bearing, real-time tire inflation is achieved, avoiding safety hazards caused by underinflated tires. Simultaneously, a reasonable sealing and venting structure ensures reliable bearing lubrication and reduces the impact of high-temperature gases on the sealing and lubrication system, thereby improving vehicle driving safety and tire lifespan. By integrating the tire inflation system into the axle hub with a liquid oil-lubricated bearing, real-time and automatic tire inflation is achieved, avoiding driving safety hazards caused by underinflated tires and extending tire lifespan. This is achieved using a rotary joint and... The one-way exhaust port promptly discharges the high-temperature gas generated during bearing operation to the atmosphere, reducing the internal pressure of the cavity and minimizing the adverse effects of high-temperature gas on seals and lubricating oil. This improves lubrication reliability and system lifespan. Multiple sealing structures, including a nut sealing ring, a lens inner hole sealing ring, a lens outer ring sealing rubber flat gasket, and a hub sealing gasket, effectively ensure the sealing of the hub bearing cavity, preventing lubricating oil leakage and the entry of external dust and moisture. This enhances the bearing's operational stability and service life. The transparent viewing window facilitates observation of the lubricating oil level and internal working condition, enabling timely detection of abnormalities and maintenance, thus improving equipment maintainability.

[0004] To achieve at least one of the advantages of the present invention, the present invention provides a structure for adding a tire inflation system to a trailer axle, including an axle body, the axle body including an axle tube and wheel hubs installed at both ends of the axle tube, a lubricated wheel hub bearing is provided between the wheel hub and the axle tube, so that the wheel hub can rotate freely relative to the axle tube, a lubrication component is provided at the outer end of the wheel hub, the lubrication component is filled with liquid lubricating oil, an inflation component is also installed on the lubrication component, the inflation component is connected to the tire valve core, and the inflation components on each wheel hub are connected in parallel to an air source.

[0005] According to one embodiment of the present invention, the lubrication assembly includes a hub axle head cover and a window lens assembly; The hub axle head cover is provided with several hub fixing screw holes. The hub cover fixing screw is inserted through the hub fixing screw holes and the hub axle head cover is installed on the outer end of the hub through the hub cover fixing screw. A hub sealing gasket is also provided between the hub axle head cover and the hub for sealing. The window lens assembly includes a pressure plate, a sealing ring for the inner hole of the lens, a transparent lens, and a sealing rubber gasket for the outer ring of the lens. The inner side of the pressure plate is provided with an annular sealing groove. The sealing ring for the inner hole of the lens is installed in the sealing groove of the pressure plate. The transparent lens and the sealing rubber gasket for the outer ring of the lens are installed sequentially on the inner end of the pressure plate. The pressure plate is provided with a pressure plate fixing screw hole. A pressure plate fixing screw is inserted through the pressure plate fixing screw hole and installs the window lens assembly on the outer end of the wheel hub axle head cover.

[0006] According to one embodiment of the present invention, an oil filling and drain plug is provided on the cylindrical surface of the wheel hub axle head cover.

[0007] According to one embodiment of the present invention, the transparent lens of the viewing window has an annular structure, and a lens through hole is provided in the middle. The size of the lens through hole is adapted to the size of the sealing ring of the inner hole of the lens; the pressure plate has an annular structure, and a pressure plate through hole is provided in the middle. The size of the pressure plate through hole is the same as the lens through hole.

[0008] According to one embodiment of the present invention, the inflation assembly includes a rotary joint and a bridge core tube. The bridge core tube passes through the interior of the bridge tube. One end of the bridge core tube is provided with a connecting air head, which is installed through the tube wall of the bridge tube. The other end of the bridge core tube extends to the wheel hub and is provided with an extension tube air nozzle quick connector. The inner end of the rotary joint is provided with a quick-connect port for the rotary joint air nozzle, which is connected to the quick-connect port for the extension tube air nozzle. It also includes a locking nut, and the locking nut and the inner and outer surfaces of the rotary joint are respectively provided with meshing rotary joint fixing threads. The inner side of the pressure plate through hole is provided with a pressure plate thread that meshes with the rotary joint fixing thread. After the rotary joint is installed inside the pressure plate through hole and connected to the bridge core tube, the locking nut is tightened to press it onto the pressure plate to realize the installation of the rotary joint. A nut sealing ring is also provided between the pressure plate and the locking nut.

[0009] According to one embodiment of the present invention, a high-pressure oil and gas exhaust port is provided on the inner end of the rotary joint, and a rotary joint one-way exhaust port is provided on the outer end of the rotary joint, and the high-pressure oil and gas exhaust port is connected to the rotary joint one-way exhaust port.

[0010] A method for installing a tire inflation system on a trailer axle includes the following steps: Step 1: Install the nut sealing ring and lock nut onto the rotary joint. Connect the rotary joint to the pressure plate by engaging the fixing threads of the pressure plate and the rotary joint. Then tighten the lock nut and adjust the rotary joint to the appropriate position. Step 2: Insert the inner hole sealing ring of the lens into the sealing groove of the pressure plate, and install the transparent lens of the window and the sealing rubber flat gasket of the outer ring of the lens in sequence to form the window lens assembly. Pass the pressure plate fixing screw through the pressure plate fixing screw hole to fix the window lens assembly on the wheel hub axle head cover. Step 3: Fix the wheel hub axle head cover to the wheel hub using the wheel hub cover fixing screws, wheel hub fixing screw holes and wheel hub sealing gaskets to achieve sealing of the wheel hub bearing cavity; Step 4: Insert the bridge core tube into the inner hole of the bridge tube, connect it to the quick-connect port of the rotary joint air nozzle through the extension tube air nozzle quick connector to form a closed air circuit, connect the air head through the hose to realize the parallel connection of multiple air components, and connect it to the trailer high-pressure air system. Step 5: Add lubricating oil to the wheel hub bearing cavity through the oil filling and drain plug until the lubricating oil level reaches the standard lubricating oil level; when the bearing generates high-temperature gas during operation, the high-temperature gas is discharged into the atmosphere in sequence through the high-pressure oil and gas exhaust port and the one-way exhaust port of the rotary joint; when the tire needs to be inflated, gas is delivered to the tire through the closed air passage. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is an exploded view of a partial structure of the present invention; In the attached diagram: 1. Rotary joint one-way exhaust port; 2. Locking nut; 3. Pressure plate fixing screw; 4. Pressure plate fixing screw hole; 5. Viewing window transparent lens; 6. Hub cover fixing screw; 7. Rotary joint; 8. High-pressure oil and gas exhaust port; 9. Nut sealing European ring; 10. Pressure plate; 11. Lens inner hole sealing European ring; 12. Lens outer ring sealing rubber flat gasket; 13. Wheel hub axle head cover; 14. Wheel hub sealing gasket; 15. Wheel hub fixing screw hole; 16. Extension tube air nozzle quick connector; 20. Lubricating oil standard oil level; 21. Bridge core tube; 22. Rotary joint air nozzle quick interface; 24. Rotary joint fixing thread; 25. Lubricated wheel hub bearing; 26. Oil filling and drain plug. Detailed Implementation

[0012] To make the objectives, technical solutions, and advantages of this invention clearer, the following description will be provided in conjunction with the appendix of this invention. Figure 1 ~Appendix Figure 2 The present invention will be described in more detail below.

[0013] The following description is intended to disclose the present invention and enable those skilled in the art to implement it. The preferred embodiments described below are merely examples, and other obvious variations will occur to those skilled in the art. The basic principles of the invention defined in the following description can be applied to other embodiments, modifications, improvements, equivalents, and other technical solutions that do not depart from the spirit and scope of the invention.

[0014] Those skilled in the art should understand that, in the disclosure of this specification, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the above terms should not be construed as limiting the present invention.

[0015] It is understood that the term "a" should be understood as "at least one" or "one or more", that is, in one embodiment, the number of an element can be one, while in another embodiment, the number of the element can be multiple, and the term "a" should not be understood as a limitation on the number.

[0016] Embodiment 1 of the present invention is as follows: A structure for adding a tire inflation system to a trailer axle includes an axle body, which includes an axle tube and wheel hubs installed at both ends of the axle tube. A lubricated wheel hub bearing 25 is provided between the wheel hub and the axle tube, allowing the wheel hub to rotate freely relative to the axle tube. The lubricated wheel hub bearing 25 needs to be kept lubricated at all times for normal operation. A lubrication component is provided at the outer end of the wheel hub, and the lubrication component is filled with liquid lubricating oil, so that the lower half of the lubricated wheel hub bearing 25 is always immersed in lubricating oil. When the vehicle is moving, the wheel hub rotates, keeping the lubricated wheel hub bearing 25 lubricated.

[0017] The lubrication assembly is also equipped with an inflation assembly, which is connected to the tire valve core. The inflation assemblies on each wheel hub are connected in parallel to an air source, which is the trailer's original high-pressure air system. A booster pump is also installed to increase the air pressure output to the standard tire pressure.

[0018] The lubrication assembly includes a hub axle cap 13 and a window lens assembly. The hub axle cap 13 is provided with several hub fixing screw holes 15. Hub fixing screws 6 are inserted through the hub fixing screw holes 15 and the hub axle cap 13 is installed on the outer end of the hub through the hub fixing screws 6. A hub sealing gasket 14 is also provided between the hub axle cap 13 and the hub for sealing. The hub sealing gasket 14 improves the seal between the hub axle cap 13 and the hub. A cap is provided at the end of the bridge tube. A sealing ring is provided in the middle of the cap. The sealing ring is a standard part on the bridge tube. The bridge core tube 21 passes through the sealing ring and is connected to the extension tube air nozzle quick connector 16.

[0019] The viewing window lens assembly includes a pressure plate 10, a lens inner hole sealing ring 11, a viewing window transparent lens 5, and a lens outer ring sealing rubber gasket 12. The pressure plate 10 has an annular sealing groove on its inner side. The lens inner hole sealing ring 11 is installed in the sealing groove of the pressure plate 10. The viewing window transparent lens 5 and the lens outer ring sealing rubber gasket 12 are sequentially installed on the inner end of the pressure plate 10. The pressure plate 10 has a pressure plate fixing screw hole 4, through which a pressure plate fixing screw 3 is inserted, mounting the viewing window lens assembly to the outer end of the hub axle cap 13. The cylindrical surface of the hub axle cap 13 has an oil filling / drain plug 26, a standard part that allows lubricating oil to be added or drained after opening. A horizontal line is marked on the viewing window transparent lens 5 to indicate the standard lubricating oil level 20. The added lubricating oil level should not be lower than this standard level 20 to ensure lubrication.

[0020] The transparent lens 5 of the viewing window has a ring structure with a lens through hole in the middle. The size of the lens through hole is adapted to the size of the sealing ring 11 of the inner hole of the lens. The pressure plate 10 has a ring structure with a pressure plate through hole in the middle. The size of the pressure plate through hole is the same as that of the lens through hole. After the rotary joint 7 is installed, its rotary joint air nozzle quick interface 22 passes through the lens through hole and the pressure plate through hole to the inside of the lubrication cavity.

[0021] The inflation assembly includes a rotary joint 7 and a core tube 21. The core tube 21 is inserted inside the axle tube. One end of the core tube 21 is provided with a connecting air head, which is installed through the tube wall of the axle tube. The connecting air heads of all tires are connected in parallel through hoses. The other end of the core tube 21 extends to the wheel hub and is provided with an extension tube nozzle quick connector 16. The inner end of the rotary joint 7 is provided with a rotary joint air nozzle quick interface 22, which is connected to the extension tube air nozzle quick interface 16 to form a closed air passage.

[0022] The locking nut 2 and the inner and outer surfaces of the rotary joint 7 are respectively provided with meshing rotary joint fixing threads 24. The inner side of the pressure plate through hole is provided with a pressure plate thread that meshes with the rotary joint fixing thread 24. After the rotary joint 7 is installed inside the pressure plate through hole and connected to the bridge core tube 21, the locking nut 2 is tightened to press it onto the pressure plate 10 to realize the installation of the rotary joint 7. A nut sealing ring 9 is also provided between the pressure plate 10 and the locking nut 2.

[0023] The inner end of the rotary joint 7 is provided with a high-pressure oil and gas exhaust port 8, and the outer end of the rotary joint 7 is provided with a rotary joint one-way exhaust port 1. The high-pressure oil and gas exhaust port 8 is connected to the rotary joint one-way exhaust port 1, which can discharge high-pressure gas and discharge the high-temperature gas generated during bearing operation to the atmosphere in a timely manner, thereby reducing the internal pressure of the cavity, reducing the adverse effects of high-temperature gas on the seals and lubricating oil, and improving lubrication reliability and system life.

[0024] Structural assembly process: 1. Installation of rotary joint 7 and seals Place the nut sealing ring 9 on the corresponding sealing position of the rotary joint 7 to ensure good contact with the sealing surface; install the lock nut 2 on the rotary joint 7, screw the rotary joint 7 into the through hole of the hub axle cover 13 through the rotary joint fixing thread 24, adjust it to a suitable axial position, connect the rotary joint 7 to the pressure plate 10 through the engagement of the fixing pressure plate thread and the rotary joint fixing thread 24, and then tighten the lock nut 2.

[0025] 2. Installation and fixing of the window lens assembly Insert the lens inner hole sealing ring 11 into the sealing groove of the pressure plate 10, ensuring that it falls completely into the groove without twisting; place the transparent lens 5 of the window on the inside of the pressure plate 10, so that its inner hole fits with the lens inner hole sealing ring 11; place the lens outer ring sealing rubber flat gasket 12 on the outside of the transparent lens 5 to form a complete window lens assembly; pass the pressure plate fixing screw 3 through the pressure plate fixing screw hole 4 and screw it into the corresponding threaded hole on the wheel hub head cover 13, tighten it evenly, so that the window lens assembly is fixed on the wheel hub head cover 13 and the seal is reliable.

[0026] 3. The hub axle cap 13 is fixed to the hub. Place a wheel hub sealing gasket 14 between the mating surfaces of the wheel hub axle cap 13 and the wheel hub, aligning it with the wheel hub fixing screw hole 15; pass the wheel hub cap fixing screw 6 through the wheel hub fixing screw hole 15 and screw it into the threaded hole on the wheel hub, tightening it evenly in sequence to make the wheel hub axle cap 13 tightly fixed to the wheel hub, thereby achieving a seal on the wheel hub bearing cavity.

[0027] 4. Connection between the axle and the air circuit The axle core tube 21 is inserted from one end of the axle body and passes through the inner hole of the axle tube, so that its two ends are connected to the corresponding air circuit interfaces. One end of the axle core tube 21 is connected to the extension tube air nozzle quick connector 16. The extension tube air nozzle quick connector 16 is connected to the rotary joint air nozzle quick interface 22 to ensure reliable connection and no air leakage, thereby forming a closed air circuit from the air source through the axle core tube 21, the extension tube air nozzle quick connector 16, the rotary joint 7 to the tire.

[0028] 5. Lubrication and venting system debugging Open the filler / drain plug 26 and inject an appropriate amount of lubricating oil into the wheel hub bearing cavity. Observe the transparent lens 5 in the sight glass. Stop adding lubricating oil when the lubricating oil level reaches the standard lubricating oil level 20, and tighten the filler / drain plug 26. Start the vehicle or rotate the wheel hub to make the wheel hub bearing run in the lubricating oil. At this time, the high-temperature gas generated by the bearing operation forms a certain pressure in the cavity. It enters the rotary joint 7 through the high-pressure oil and gas exhaust port 8 and is automatically discharged to the atmosphere through the one-way exhaust port 1 of the rotary joint. The one-way exhaust port 1 of the rotary joint has a one-way valve structure inside, and the gas can only be discharged from the inside to the outside in one direction. Check whether there is any leakage in each sealing part. If necessary, adjust the seals or fasteners appropriately to ensure that the sealing and venting effect meets the design requirements.

[0029] How to use: During normal vehicle operation, when the trailer's built-in tire pressure monitoring sensor detects that the tire pressure is lower than the set value, the air source inflates the tires through the axle core tube 21, the extension tube valve quick connector 16, the rotary connector valve quick interface 22, and the internal air passage of the rotary connector 7 until the tire pressure returns to the set value, thus achieving automatic inflation. The input air pressure is the same as the standard tire pressure. If the pressure of any tire is lower than the standard set value, the air source will input high-pressure air. At this time, the tire with the lower tire pressure will be inflated, while the tire with the same tire pressure as the standard tire pressure will not be inflated, thus ensuring that the tire pressure of all tires is always consistent and the same as the standard pressure.

[0030] Meanwhile, the wheel hub bearing operates at high speed under liquid oil lubrication, and the high-temperature gas and a small amount of oil-gas mixture generated accumulate in the wheel hub bearing cavity, causing the pressure inside the cavity to rise. When the pressure reaches a certain value, the high-temperature gas enters the rotary joint 7 through the high-pressure oil-gas exhaust port 8, and is discharged to the atmosphere through the one-way exhaust port 1 of the rotary joint, thereby effectively reducing the pressure inside the cavity, preventing the lubricating oil from deteriorating or leaking due to high temperature and high pressure, and ensuring the long-term stable operation of the wheel hub bearing. This working mechanism is determined by the working air pressure of the one-way valve structure of the one-way exhaust port 1 of the rotary joint. This standard working air pressure is set during production. When the pressure exceeds this air pressure, the one-way valve structure will start to discharge gas. The specific structure and working principle of the one-way valve are common knowledge and will not be described in detail.

[0031] Through the transparent lens 5, the operator can observe the lubricating oil level and the approximate working condition of the wheel hub bearing cavity at any time. If the oil level is found to be too low or there are abnormal impurities, the lubricating oil can be replenished or replaced in time through the oil filling and drain plug 26, thereby improving maintenance efficiency.

[0032] It should be noted that the terms "first, second, and third" used in this invention are for descriptive purposes only and do not indicate any order. They should not be construed as indicating or implying relative importance and can be interpreted as names.

[0033] Those skilled in the art should understand that the embodiments of the present invention described above and shown in the accompanying drawings are merely examples and do not limit the invention. The advantages of the present invention have been fully and effectively realized. The functional and structural principles of the present invention have been demonstrated and explained in the embodiments; without departing from these principles, the implementation of the present invention may be modified or altered in any way.

Claims

1. A structure for adding a tire inflation system to a trailer axle, comprising an axle body, the axle body including an axle tube and wheel hubs mounted at both ends of the axle tube, wherein a lubricated wheel hub bearing is provided between the wheel hub and the axle tube, allowing the wheel hub to rotate freely relative to the axle tube, characterized in that, A lubrication assembly is provided on the outer end of the wheel hub. The lubrication assembly is filled with liquid lubricating oil. An inflation assembly is also installed on the lubrication assembly. The inflation assembly is connected to the tire valve core. The inflation assemblies on each wheel hub are connected in parallel to an air source.

2. The structure of the trailer axle with tire inflation system according to claim 1, characterized in that: The lubrication assembly includes a hub axle head cover and a viewing window lens assembly; The hub axle head cover is provided with several hub fixing screw holes. A hub cover fixing screw is inserted through the hub fixing screw hole and the hub axle head cover is installed on the outer end of the hub through the hub cover fixing screw. A hub sealing gasket is also provided between the hub axle head cover and the hub for sealing. The viewing window lens assembly includes a pressure plate, a sealing ring for the inner hole of the lens, a transparent viewing window lens, and a sealing rubber gasket for the outer ring of the lens. The pressure plate has an annular sealing groove on its inner side, and the sealing ring for the inner hole of the lens is installed in the sealing groove of the pressure plate. The transparent viewing window lens and the sealing rubber gasket for the outer ring of the lens are sequentially installed on the inner end of the pressure plate. The pressure plate has a pressure plate fixing screw hole, and a pressure plate fixing screw is inserted through the pressure plate fixing screw hole to install the viewing window lens assembly on the outer end of the wheel hub axle head cover.

3. The structure of the trailer axle with tire inflation system according to claim 2, characterized in that: The cylindrical surface of the wheel hub axle cover is provided with an oil filling / draining plug.

4. The structure of the trailer axle with tire inflation system according to claim 2, characterized in that: The transparent lens of the viewing window has a ring structure with a lens through hole in its middle. The size of the lens through hole is adapted to the size of the sealing ring of the inner hole of the lens. The pressure plate has a ring structure with a pressure plate through hole in its middle. The size of the pressure plate through hole is the same as the lens through hole.

5. The structure of the trailer axle with tire inflation system according to claim 4, characterized in that: The inflation assembly includes a rotary joint and a bridge core tube. The bridge core tube passes through the inside of the bridge tube. One end of the bridge core tube is provided with a connecting air head, which is installed through the tube wall of the bridge tube. The other end of the bridge core tube extends to the wheel hub and is provided with an extension tube air nozzle quick connector. The inner end of the rotary joint is provided with a rotary joint air nozzle quick interface, which is connected to the extension tube air nozzle quick interface. It also includes a locking nut, and the locking nut and the inner and outer surfaces of the rotary joint are respectively provided with meshing rotary joint fixing threads. The inner side of the pressure plate through hole is provided with a pressure plate thread that meshes with the rotary joint fixing thread. After the rotary joint is installed inside the pressure plate through hole and connected to the bridge core tube, the locking nut is tightened to press it onto the pressure plate to realize the installation of the rotary joint. A nut sealing ring is also provided between the pressure plate and the locking nut.

6. The structure for adding a tire inflation system to a trailer axle according to claim 5, characterized in that: The inner end of the rotary joint is provided with a high-pressure oil and gas exhaust port, and the outer end of the rotary joint is provided with a rotary joint one-way exhaust port. The high-pressure oil and gas exhaust port is connected to the rotary joint one-way exhaust port.

7. A method for adding a tire inflation system to a trailer axle according to any one of claims 1-6, characterized in that, Includes the following steps: Step 1: Install the nut sealing ring and lock nut onto the rotary joint. Connect the rotary joint to the pressure plate by engaging the threads of the fixed pressure plate and the fixed threads of the rotary joint. Then tighten the lock nut and adjust the rotary joint to the appropriate position. Step 2: Insert the inner hole sealing ring of the lens into the sealing groove of the pressure plate, and install the transparent lens of the window and the sealing rubber flat gasket of the outer ring of the lens in sequence to form the window lens assembly. Pass the pressure plate fixing screw through the pressure plate fixing screw hole to fix the window lens assembly on the wheel hub axle head cover. Step 3: Fix the wheel hub axle head cover to the wheel hub using the wheel hub cover fixing screws, wheel hub fixing screw holes and wheel hub sealing gaskets to achieve sealing of the wheel hub bearing cavity; Step 4: Insert the bridge core tube into the inner hole of the bridge tube, connect it to the quick-connect port of the rotary joint air nozzle through the extension tube air nozzle quick connector to form a closed air circuit, connect the air head through the hose to realize the parallel connection of multiple air components, and connect to the trailer high-pressure air system. Step 5: Add lubricating oil to the wheel hub bearing cavity through the oil filling and drain plug until the lubricating oil level reaches the standard lubricating oil level; when the bearing generates high-temperature gas during operation, the high-temperature gas is discharged into the atmosphere through the high-pressure oil and gas exhaust port and the one-way exhaust port of the rotary joint in sequence; when the tire needs to be inflated, gas is delivered to the tire through the closed air passage.

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