Inflation needle head structure of CDC shock absorber and use method of inflation needle head structure

Abstract

The invention provides a CDC shock absorber inflation needle head structure and a using method, and relates to the technical field of automobile chassis shock absorbers, the CDC shock absorber inflation needle head structure comprises an inflation integrated needle head, one end of the inflation integrated needle head is provided with an assembly groove, and the other end is provided with an annular insertion piece; a plurality of air inlet grooves communicated with the assembling groove are formed in the inner side wall of the annular inserting piece; an air inlet hole communicated with the assembling groove is formed in the side wall or the end part of the inflating integrated needle head; the bidirectional dynamic sealing oil seal is arranged in the assembling groove; and the fine tuning nut is in threaded connection with the inflatable integrated needle head to press the oil seal. The annular inserting piece is directly inserted into the shock absorber oil seal lip to form interference fit, nitrogen enters a shock absorber air chamber through the air inlet hole, the assembling groove and the air inlet groove in sequence, and inflation and sealing integration is achieved. According to the structure, the gas leakage amount is remarkably reduced, the sealing reliability is improved, quick remodeling of shock absorbers of different specifications is achieved through modular design, and the inflation efficiency and quality are effectively improved.

Description

Technical Field

[0001] This invention mainly relates to the field of automotive chassis shock absorber technology, specifically to a CDC shock absorber inflation needle structure and its usage method. Background Technology

[0002] With the continuous development of the automotive industry, domestic and international customers have placed higher demands on the performance, service life, and cost control of CDC shock absorbers. As a key component of the automotive chassis system, optimizing the manufacturing process of shock absorbers is of great significance for improving product quality and production efficiency.

[0003] In the production and R&D of shock absorbers, the nitrogen filling process is a crucial step to ensure that the pressure in the shock absorber's air chamber meets design requirements. This process is usually carried out after sealing. Nitrogen is injected into the shock absorber's air chamber through an inflation needle, and a servo motor drives a tension / compression sensor to detect the counterforce value to determine whether the air chamber pressure is up to standard. Currently, the inflation needles commonly used in the industry are single-needle structures, mostly made of ABS plastic or other soft materials. Although simple in structure and low in cost, they suffer from poor durability and frequent replacement.

[0004] Furthermore, in the existing inflation process, the inflation needle needs to be used in conjunction with an inflation sealing fixture, resulting in a complex overall structure. During inflation, gas leakage is prone to occur due to the non-precision machining of the shock absorber's outer cylinder surface. This leakage not only affects the accurate control of the air chamber pressure but also reduces inflation efficiency, requiring frequent reliance on a counterforce detection system for verification, further slowing down production.

[0005] On the other hand, due to the differences in the outer diameter of the hydraulic cylinder and the size of the compression rod of the front and rear shock absorbers of different models and even the same model, the existing air-filled sealing tooling needs to be specially designed and replaced for different products, resulting in poor versatility, a large number of tooling, inconvenience in changing models, and waste of resources. Summary of the Invention

[0006] 1. The technical problem that the invention aims to solve: The present invention provides a CDC shock absorber inflation needle structure and usage method to solve the technical problems existing in the background art.

[0007] 2. Technical Solution: To achieve the above objectives, the technical solution provided by this invention is: a CDC shock absorber inflation needle structure, comprising... An integrated inflation needle, one end of which is provided with an assembly groove, and the other end is provided with an annular plug for direct insertion into the oil seal lip of the shock absorber. The inner sidewall of the annular insert is provided with several air inlet grooves, which are connected to the assembly groove. The side wall or end of the inflatable integrated needle is provided with an air inlet for connecting an external air source, and the air inlet communicates with the assembly groove; A bidirectional dynamic sealing oil seal is fitted into the mounting groove of the integrated inflatable needle. A fine-tuning nut is threaded to one end of the integrated inflation needle with an assembly groove, used to press and fix the bidirectional dynamic sealing oil seal. The annular insert is configured such that after being inserted into the oil seal lip of the shock absorber, its outer wall forms a seal with the inner wall of the oil seal lip; nitrogen supplied by an external air source can enter the shock absorber air chamber sequentially through the air inlet, the mounting groove, and the air inlet slot. During operation, first, select and assemble the matching integrated inflation needle, bidirectional dynamic sealing oil seal, and fine-tuning nut according to the specifications of the shock absorber to be inflated. Then, insert one end of the assembled inflation needle structure's annular insert along the compression rod axis of the shock absorber until the annular insert is completely inside the oil seal lip of the shock absorber. At this point, the bidirectional dynamic sealing oil seal forms an effective seal with the outer wall of the compression rod, while an extremely narrow annular inflation gap is formed between the outer wall of the annular insert and the inner wall of the oil seal lip.

[0008] Next, the output end of the external nitrogen inflation device is sealed and connected to the air inlet on the integrated inflation needle. At the start of inflation, high-pressure nitrogen enters the space of the mounting groove through the air inlet, and then flows evenly to its end through the various air inlet slots on the inner side of the annular insert. Finally, the nitrogen passes through the annular inflation gap, bypasses the oil seal lip, and is injected into the sealed air chamber of the shock absorber. By integrating inflation and sealing functions into a compact, integrated needle structure, replacing the original bulky and leak-prone separate sealing fixture, the amount of gas leakage during inflation is significantly reduced. When different shock absorbers need to be inflated, simply unscrew the integrated inflation needle for replacement. Replacing the annular insert inflation needle with a suitable size allows for quick and convenient replacement and adaptation between different models of shock absorbers.

[0009] Furthermore, an adjusting shim is provided between the bidirectional dynamic sealing oil seal and the fine-tuning nut.

[0010] Furthermore, the adjusting shim is made of rubber, polytetrafluoroethylene, or any one of metal materials such as copper or stainless steel.

[0011] Furthermore, the inner wall of the annular connector has four air intake slots, which are arranged in a cross shape.

[0012] Furthermore, the annular insert is a thin-walled cylindrical structure, and its outer diameter is adapted to the inner diameter of the shock absorber oil seal lip to achieve an interference fit.

[0013] Furthermore, the adjusting shim and the bidirectional dynamic sealing oil seal are coated with grease.

[0014] Furthermore, the sidewall of the inflatable integrated needle is provided with at least two air inlets, each of which is connected to an internal mounting groove; and at least one of the air inlets is configured to be connected to a pressure detection device.

[0015] And a method of using a CDC shock absorber inflation needle structure, including the following steps: Assembly steps: Place the bidirectional dynamic sealing oil seal into the mounting groove of the integrated inflation needle, then screw the fine-tuning nut into the end of the integrated inflation needle with the mounting groove and tighten it to form an integrated inflation unit. Insertion and sealing steps: Insert one end of the annular plug-in piece of the integrated inflation unit along the axial direction of the compression rod of the shock absorber until the annular plug-in piece is completely inserted into the oil seal lip of the shock absorber; at this time, the bidirectional dynamic sealing oil seal and the outer wall of the compression rod form a dynamic seal, and at the same time, an annular inflation gap is formed between the annular plug-in piece and the inner wall of the oil seal lip. Connection and inflation steps: Seal and connect the external nitrogen inflation device to at least one air inlet on the integrated inflation needle, turn on the air source, and let the nitrogen flow through the air inlet, the mounting groove, and the air inlet slot in sequence to inflate the shock absorber air chamber.

[0016] Furthermore, the assembly step also includes applying grease to the sealing lip of the bidirectional dynamic sealing oil seal. When the structure includes an adjusting shim, grease is applied between the contact surface of the adjusting shim and the bidirectional dynamic sealing oil seal and / or the contact surface of the adjusting shim and the fine-tuning nut.

[0017] Furthermore, in the connection and inflation step, the air pressure detection device is connected to another air inlet on the integrated inflation needle that is not occupied by the nitrogen inflation device, to monitor the inflation pressure in real time.

[0018] 3. Beneficial effects: Compared with the prior art, the technical solution provided by this invention has the following advantages: This invention is rationally designed. By integrating the inflation needle and sealing function into a single structure, it replaces the traditional separate tooling. This allows the annular insert plate and the oil seal lip to form an interference fit, significantly improving sealing performance, reducing nitrogen leakage, and effectively solving the problem of serious gas leakage in the original process.

[0019] This structure achieves uniform and stable inflation through a multi-hole air intake and a cross-shaped groove design. Combined with an integrated air pressure detection interface, it enables real-time in-situ monitoring of inflation pressure, improving the controllability and accuracy of the inflation process, avoiding reliance on indirect counterforce detection, and significantly improving inflation quality and efficiency.

[0020] The modular quick-change design allows for the replacement of only the corresponding size of the integrated inflation needle and oil seal for different specifications of shock absorbers, without the need to replace the entire tooling. This significantly reduces the number of supporting fixtures, enables rapid model changeover, lowers equipment costs and maintenance difficulty, and improves production adaptability.

[0021] It should be noted that the structures not described in this invention are not related to the design points and improvement directions of this invention, and are the same as or can be implemented using existing technologies, so they will not be elaborated here. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is an exploded view of the structure of the present invention; Figure 3 This is a schematic diagram of the invention installed on a shock absorber; Figure 4 This is a schematic diagram of the cross-sectional structure of the present invention installed in the shock absorber; Figure 5 For the present invention Figure 4 An enlarged schematic diagram of the structure at point A.

[0023] Figure label: 1. Inflatable integrated needle; 2. Assembly groove; 3. Annular insert piece; 4. Air inlet groove; 5. Air inlet hole; 6. Two-way dynamic sealing oil seal; 7. Fine-tuning nut; 8. Adjusting shim. Detailed Implementation

[0024] To facilitate understanding of the present invention, a more complete description of the invention will be given below with reference to the accompanying drawings, which illustrate several embodiments of the invention. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of the invention will be more thorough and complete.

[0025] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "page," "bottom," "inner," "outer," "clockwise," and "counterclockwise," 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 this 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, they should not be construed as limitations on this invention.

[0026] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0027] In this invention, unless otherwise explicitly specified and limited, the terms "installed," "connected," "linked," "fixed," "provided with," and "located in" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0028] It should be noted that structures not described in this invention do not involve the design points and improvement directions of this invention, and can all be achieved using existing technologies known to those skilled in the art.

[0029] The specific implementation of the present invention will be described in detail below with reference to specific embodiments.

[0030] See attached document Figure 1-5 A CDC shock absorber inflation needle structure, including An integrated inflation needle 1, one end of which is provided with an assembly groove 2, and the other end is provided with an annular plug-in piece 3 for direct insertion into the oil seal lip of the shock absorber. The inner sidewall of the annular insert 3 is provided with a plurality of air inlet grooves 4, and the air inlet grooves 4 are connected to the assembly groove 2. The side wall or end of the inflatable integrated needle 1 is provided with an air inlet 5 for connecting an external air source, and the air inlet 5 communicates with the assembly groove 2. A bidirectional dynamic sealing oil seal 6 is fitted into the mounting groove 2 of the integrated inflatable needle 1; The fine-tuning nut 7 is threaded to one end of the integrated inflation needle 1 that has an assembly groove 2, and is used to press and fix the bidirectional dynamic sealing oil seal 6. The annular insert 3 is configured such that after being inserted into the oil seal lip of the shock absorber, its outer wall forms a seal with the inner wall of the oil seal lip; nitrogen gas supplied by an external gas source can enter the shock absorber air chamber sequentially through the air inlet 5, the assembly groove 2, and the air inlet slot 4. In this embodiment, firstly, according to the specifications of the shock absorber to be inflated, a matching integrated inflation needle 1, a bidirectional dynamic sealing oil seal 6, and a fine-tuning nut 7 are selected and assembled. Then, one end of the annular insert 3 of the assembled inflation needle structure is inserted axially along the compression rod of the shock absorber until the annular insert 3 is completely inserted into the oil seal lip of the shock absorber. At this time, the bidirectional dynamic sealing oil seal 6 forms an effective seal with the outer wall of the compression rod, while an extremely narrow annular inflation gap is formed between the outer wall of the annular insert 3 and the inner wall of the oil seal lip.

[0031] Next, the output end of the external nitrogen inflation device is sealed and connected to the air inlet 5 on the integrated inflation needle 1. At the start of inflation, high-pressure nitrogen enters the space of the mounting groove 2 through the air inlet 5, and then flows evenly to its ends through the various air inlet slots 4 inside the annular insert 3. Finally, the nitrogen passes through the annular inflation gap, bypasses the oil seal lip, and is injected into the sealed air chamber of the shock absorber.

[0032] This embodiment integrates the inflation and sealing functions into a compact, integrated needle structure, replacing the original bulky and leak-prone separate sealing fixture. This significantly reduces gas leakage during the inflation process. When different shock absorbers need to be inflated, simply unscrew the integrated inflation needle 1 for replacement. Replace the integrated inflation needle 1 with a matching annular connector 3, enabling quick and convenient replacement and adaptation between different models of shock absorbers.

[0033] An adjusting shim 8 is provided between the bidirectional dynamic sealing oil seal 6 and the fine-tuning nut 7. In this embodiment, when the fine-tuning nut 7 is tightened, it can more evenly transmit the axial clamping force to the bidirectional dynamic sealing oil seal 6, thereby optimizing the radial deformation of the oil seal and making its fit with the shock absorber compression rod more tight and uniform, which helps to further improve the reliability of the dynamic seal. At the same time, the presence of the shim can compensate for the micro-unevenness that may exist in the machining, avoid stress concentration, protect the oil seal end face and the contact surface of the fine-tuning nut 7, and extend the service life of key components.

[0034] The material of the adjusting shim 8 is any one of rubber, polytetrafluoroethylene, or metal materials such as copper or stainless steel. The material of the adjusting shim 8 can be selected according to the specific working conditions. By selecting adjusting shims 8 of different materials and thicknesses, the compression state of the bidirectional dynamic sealing oil seal 6 can be finely adjusted so that it can better adapt to different assembly tolerances and working pressure conditions, ensuring that the air-filled needle structure can maintain stable and durable sealing performance in various shock absorber products.

[0035] The annular insert 3 has four air inlet slots 4 on its inner sidewall, arranged in a cross shape. In this embodiment, this cross-shaped arrangement creates multiple evenly distributed air inlet channels around the annular insert 3. During inflation, nitrogen flows evenly and synchronously through these four channels to the annular inflation gap, ensuring that the gas is injected into the shock absorber chamber in a balanced and stable manner. This helps to avoid abnormal deformation of the oil seal lip or unstable sealing caused by uneven airflow pressure on one side, thus improving the smoothness and reliability of the inflation process.

[0036] It should be noted that the cross-shaped distribution is a preferred and effective arrangement of the air intake slots 4, but the scope of protection of this invention is not limited to this specific number and arrangement. Under the concept of this invention, those skilled in the art can adaptively adjust the number of air intake slots 4, such as three or six, and their circumferential distribution, such as uniform distribution or other symmetrical distribution, according to the actual inflation flow rate, uniformity requirements, and processing technology. These variations based on the same principle should all be considered to fall within the scope of protection of this invention.

[0037] The annular insert 3 is a thin-walled cylindrical structure, and its outer diameter is adapted to the inner diameter of the shock absorber oil seal lip to achieve an interference fit. In this embodiment, the annular insert 3 is specifically designed as a thin-walled cylindrical structure. This structural design enables the insert to have a certain elastic deformation capacity, thereby allowing it to be smoothly inserted into the oil seal lip and reducing insertion resistance.

[0038] The key is that the outer diameter of the annular insert 3 is precisely set to be slightly larger than the inner diameter of the target shock absorber oil seal lip. This dimensional relationship ensures an interference fit when the annular insert 3 is inserted into the oil seal lip. This interference fit ensures a tight and uniform contact between the outer wall of the annular insert 3 and the inner wall of the oil seal lip, resulting in an extremely fine and controllable annular inflation gap. This not only provides a stable flow path for nitrogen, but more importantly, it constitutes the first effective sealing barrier, significantly suppressing excessive nitrogen leakage along the inner side of the oil seal lip during inflation. This is one of the core design features for achieving low-leakage inflation.

[0039] The thin-walled cylindrical structure is preferably made of metal materials such as stainless steel or brass, which have both strength and good ductility, so as to provide the necessary elastic deformation capacity while ensuring structural rigidity, and to ensure the sealing effect and service life of the interference fit.

[0040] The adjusting shim 8 and the bidirectional dynamic sealing oil seal 6 are coated with grease. In this embodiment, before assembling the integrated inflation needle 1 to the shock absorber compression rod, an appropriate amount of grease can be applied to the sealing lip of the bidirectional dynamic sealing oil seal 6. This significantly reduces the frictional resistance and wear of the oil seal during insertion and subsequent relative movement with the compression rod, ensuring the smoothness and durability of the dynamic seal, while also helping to fill microscopic unevenness and improve the initial sealing effect.

[0041] Furthermore, if the structure includes an adjusting shim 8, grease can be applied between the adjusting shim 8 and the end face of the bidirectional dynamic sealing oil seal 6 and / or the contact surface with the fine-tuning nut 7. This helps reduce friction between the contact surfaces when tightening the fine-tuning nut 7, making the clamping force transmission more uniform, avoiding component twisting or seal distortion caused by dry friction, thereby ensuring accurate application of preload and stable sealing.

[0042] The selection of the grease must consider its compatibility with hydraulic oil and rubber materials, as well as its operating temperature range, to ensure its long-term effectiveness. Through the above lubrication treatment, this inflation needle structure can more reliably achieve low-leakage and long-life inflation operations.

[0043] The integrated inflation needle 1 has at least two air inlets 5 on its sidewall, each of which communicates with an internal mounting groove 2. Furthermore, at least one of the air inlets 5 is configured to connect to a pressure detection device. In this embodiment, to improve air intake efficiency and reliability, and to enable real-time monitoring of the inflation process, the structure of the air inlets 5 is specially designed. Specifically, multiple air inlets 5 are provided on the sidewall of the integrated inflation needle 1. These air inlets 5 are arranged circumferentially around the sidewall of the needle and are each independently and directly communicated with an internal mounting groove 2.

[0044] This multi-hole air intake design is equivalent to establishing multiple parallel gas flow channels between the air source and the assembly groove 2. Its advantage lies in effectively increasing the total air intake flow area, reducing airflow resistance, and allowing nitrogen to fill the assembly groove 2 more quickly, thereby improving the inflation response speed and uniformity.

[0045] Most importantly, at least one of the air inlets 5 is specifically designed for connecting a pressure detection device, such as a pressure sensor or pressure gauge. This allows the operator to directly and in real-time monitor the gas pressure flowing through the integrated inflation needle 1 during inflation. This structure integrates inflation and pressure detection functions into one unit, eliminating the need for additional complex detection fixtures in the inflation pipeline. This achieves in-situ, efficient monitoring of the inflation pressure in the shock absorber's air chamber, providing a direct basis for determining whether the inflation quality is up to standard. It effectively solves the problems of uncontrollable inflation pressure and reliance on indirect counterforce detection in the prior art.

[0046] Those skilled in the art will understand that the specific number, diameter, and circumferential distribution of the multiple air inlets 5 can be adaptively selected and set according to the actual required airflow, detection needs, and structural strength.

[0047] The method of using the CDC shock absorber inflation needle structure includes the following steps: Assembly steps: Set the bidirectional dynamic sealing oil seal 6 into the mounting groove 2 of the integrated inflation needle 1, then screw the fine-tuning nut 7 into the end of the integrated inflation needle 1 with the mounting groove 2 and tighten it to form an integrated inflation unit. Insertion and sealing steps: Insert one end of the annular plug-in piece 3 of the integrated inflation unit along the axial direction of the compression rod of the shock absorber until the annular plug-in piece 3 is completely inserted into the oil seal lip of the shock absorber; at this time, the bidirectional dynamic sealing oil seal 6 forms a dynamic seal with the outer wall of the compression rod, and at the same time, an annular inflation gap is formed between the annular plug-in piece 3 and the inner wall of the oil seal lip. Connection and inflation steps: Seal and connect the external nitrogen inflation device to at least one air inlet 5 on the integrated inflation needle 1, turn on the gas source, and let the nitrogen gas pass through the air inlet 5, the mounting groove 2, and the air inlet slot 4 in sequence to fill the shock absorber air chamber.

[0048] The assembly step also includes applying grease to the sealing lip of the bidirectional dynamic sealing oil seal 6. When the structure includes an adjusting shim 8, grease is applied between the contact surface of the adjusting shim 8 and the bidirectional dynamic sealing oil seal 6 and / or the contact surface of the adjusting shim 8 and the fine-tuning nut 7.

[0049] During the connection and inflation step, the air pressure detection device is connected to another air inlet 5 on the integrated inflation needle 1 that is not occupied by the nitrogen inflation device, to monitor the inflation pressure in real time.

[0050] The above-described embodiments are merely illustrative of certain implementations of the present invention, and are described in a relatively specific and detailed manner. However, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements are all within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. A CDC shock absorber inflation needle structure, characterized in that: include An integrated inflation needle (1) is provided with an assembly groove (2) at one end and an annular plug-in piece (3) at the other end for direct insertion into the oil seal lip of the shock absorber. The inner wall of the annular insert (3) is provided with several air inlet grooves (4), and the air inlet grooves (4) are connected to the assembly groove (2); The side wall or end of the inflatable integrated needle (1) is provided with an air inlet (5) for connecting an external air source, and the air inlet (5) is connected to the assembly groove (2). A bidirectional dynamic sealing oil seal (6) is fitted into the mounting groove (2) of the inflatable integrated needle (1); The fine-tuning nut (7) is threaded to one end of the inflatable integrated needle (1) which has an assembly groove (2) for pressing and fixing the bidirectional dynamic sealing oil seal (6). The annular insert (3) is configured such that after being inserted into the oil seal lip of the shock absorber, its outer wall forms a seal with the inner wall of the oil seal lip; nitrogen gas supplied by an external gas source can enter the shock absorber air chamber in sequence through the air inlet (5), the assembly groove (2), and the air inlet slot (4).

2. The CDC shock absorber inflation needle structure according to claim 1, characterized in that: An adjusting shim (8) is provided between the bidirectional dynamic sealing oil seal (6) and the fine-tuning nut (7).

3. The CDC shock absorber inflation needle structure according to claim 1, characterized in that: The adjusting shim (8) is made of rubber, polytetrafluoroethylene, or any of the following metal materials: copper or stainless steel.

4. The CDC shock absorber inflation needle structure according to claim 1, characterized in that: The inner wall of the annular connector (3) has four air intake slots (4), and the four air intake slots (4) are arranged in a cross shape.

5. The CDC shock absorber inflation needle structure according to claim 1, characterized in that: The annular insert (3) is a thin-walled cylindrical structure, and its outer diameter is adapted to the inner diameter of the oil seal lip of the shock absorber to achieve an interference fit.

6. The CDC shock absorber inflation needle structure according to claim 2, characterized in that: The adjusting shim (8) and the bidirectional dynamic sealing oil seal (6) are coated with grease.

7. The CDC shock absorber inflation needle structure according to claim 1, characterized in that: At least two air inlets (5) are provided on the side wall of the inflatable needle (1), and the air inlets (5) are connected to the internal mounting groove (2); and at least one of the air inlets (5) is configured to be connected to a pressure detection device.

8. A method of using the CDC shock absorber inflation needle structure as described in any one of claims 1-7, characterized in that: Includes the following steps: Assembly steps: Place the bidirectional dynamic sealing oil seal (6) into the mounting groove (2) of the integrated inflation needle (1), and then screw the fine-tuning nut (7) into the end of the integrated inflation needle (1) with the mounting groove (2) and tighten it to form an integrated inflation unit. Insertion and sealing steps: Insert one end of the annular plug-in piece (3) of the integrated inflation unit along the axial direction of the compression rod of the shock absorber until the annular plug-in piece (3) is completely inserted into the oil seal lip of the shock absorber; at this time, the bidirectional dynamic sealing oil seal (6) forms a dynamic seal with the outer wall of the compression rod, and at the same time, an annular inflation gap is formed between the annular plug-in piece (3) and the inner wall of the oil seal lip. Connection and inflation steps: Seal the external nitrogen inflation device to at least one air inlet (5) on the inflation needle (1), turn on the gas source, and let the nitrogen gas pass through the air inlet (5), the mounting groove (2), and the air inlet slot (4) in sequence to fill the shock absorber air chamber.

9. A method of using the CDC shock absorber inflation needle structure as described in claim 8, characterized in that: The assembly step also includes applying grease to the sealing lip of the bidirectional dynamic sealing oil seal (6). When the structure includes an adjusting shim (8), grease is applied between the contact surface of the adjusting shim (8) and the bidirectional dynamic sealing oil seal (6) and / or the contact surface of the adjusting shim (8) and the fine-tuning nut (7).

10. A method of using the CDC shock absorber inflation needle structure as described in claim 8, characterized in that: In the connection and inflation step, the air pressure detection device is connected to another air inlet (5) on the inflation needle (1) that is not occupied by the nitrogen inflation device, and the inflation pressure is monitored in real time.

Images