A gas charging structure for a nitrogen shock absorber having a self-preloading elastic spool

Abstract

The present application relates to the technical field of shock absorber, in particular to a nitrogen shock absorber inflation structure with self-preloading elastic valve core; the present application can realize elastic sealing for the floating piston by setting the floating piston assembly; when the nitrogen filling gun connector is aligned with the detachable screw plug, the high-pressure nitrogen gun is aligned with the inflation hole of the guide column part to perform inflation, which can make the ejector rod overcome the elastic force of the rubber of the elastic lip part, and then open the tapered sealing part of the elastic valve core, so that the high-pressure nitrogen enters the closed air cavity; after the inflation is completed, the elastic lip part is automatically reset, the elastic valve core is elastically closed and sealed, and the detachable screw plug with sealing effect is screwed in to increase the sealing insurance; the traditional complex "multi-piece superimposed valve" is replaced by "single self-preloading elastic valve core", and the inflation interface is integrated at the bottom of the shock absorber, which realizes the substantial reduction of manufacturing cost and the improvement of maintenance convenience.

Description

Technical Field

[0001] This invention relates to the field of vibration damper technology, specifically to an inflation structure for a nitrogen vibration damper with a self-preloaded elastic valve core. Background Technology

[0002] Nitrogen shock absorbers are widely used in motorcycles, automobiles, off-road equipment, and industrial vibration damping. Their performance stability largely depends on the sealing reliability of the high-pressure nitrogen in the gas chamber and the operability of the initial inflation process. In the production and after-sales maintenance of shock absorber assemblies, filling the shock absorber with a fixed amount of high-pressure nitrogen requires a dedicated inflation structure and matching inflation equipment.

[0003] The current industry practice is to pre-install an inflation channel at the bottom of the shock absorber cylinder or the air storage end cover. The channel is equipped with a one-way valve consisting of more than ten parts, such as springs, steel balls / valve plates, guide sleeves, O-rings, and locking circlips. During inflation, a special nitrogen filling gun, a high-pressure reducing valve, a pressure sensor, and a pressure holding fixture are required. Some production lines even use automatic rotary air filling machines. The purchase cost of a single piece of equipment is several million yuan, and the air circuit and electrical control system need to be calibrated and maintained regularly.

[0004] The above plan has three prominent problems: 1. Redundant valve body structure and long chain of parts; Springs provide preload, steel balls / valve plates provide opening and closing, snap rings provide limiting, guide sleeves prevent deviation, and multiple O-rings prevent gas leakage—failure in any of these areas will result in leakage. The more parts there are, the more difficult it is to control batch consistency, and assembly time and scrap rates increase simultaneously.

[0005] 2. The supporting inflation equipment is expensive and takes up a lot of space; Traditional nitrogen filling stations require pressure reducing valves, high-pressure hoses, quick connectors, pressure gauges or sensors, and pressure holding clamps, which are difficult for small and medium-sized parts manufacturers and after-sales stores to afford; temporary nitrogen replenishment in the wild or on the track is almost impossible.

[0006] 3. Primarily one-time packaging; no replacements available after sale. Most original equipment manufacturer (OEM) shock absorbers use bottom cover rivets, ball valves, or welded plugs, which are sealed at the factory. As the air pressure decreases during use, the entire unit must be scrapped, which does not conform to the current trend of repairable and recyclable products.

[0007] Although some improvement solutions attempt to reduce the number of parts by using rubber lip valves or magnetic valves, they still do not break away from the framework of "multiple components stacked together + complex external air circuits", and the manufacturing cost and equipment dependence have not been substantially reduced.

[0008] When existing nitrogen shock absorbers are in use, the floating piston reciprocates within the cylinder and is prone to uneven wear due to lateral forces, resulting in rapid wear of the sealing rings and nitrogen leakage. Nitrogen leakage leads to a decrease in pre-pressure, insufficient shock absorber support, and vehicle body sagging. Furthermore, it is difficult to simultaneously achieve both low-speed, small-bump comfort and high-speed, large-impact support.

[0009] Therefore, the market urgently needs a nitrogen damper inflation solution with very few valve body parts (which can be controlled within 3-5 pieces), no need for springs / steel balls / circlips, can be manually replenished with nitrogen directly using a common air source connector, and has the same structure for both factory and after-sales use. Summary of the Invention

[0010] To address the issues of redundant inflation valve structures, expensive inflation equipment, and the inability to replenish nitrogen in nitrogen dampers when using inflation structures with self-preloaded elastic valve cores, this invention provides an inflation structure for nitrogen dampers with a self-preloaded elastic valve core to solve the aforementioned problems.

[0011] To achieve the above objectives, the present invention provides the following technical solution: A nitrogen damper inflation structure with a self-preloaded elastic valve core includes a damper cylinder, a piston rod is slidably connected to the port of the damper cylinder, and an oil chamber valve core is fixedly installed on one end of the piston rod extending to the inner wall of the damper cylinder. The bottom outer wall of the shock absorber cylinder is provided with an air valve assembly for self-pre-tightening elastic sealing during air filling, and the inner wall of the shock absorber cylinder is provided with a floating piston assembly for elastic limiting. The inflation valve assembly includes a valve housing, which is screwed onto the bottom of the shock absorber cylinder for fastening. A sealed air chamber is formed between the valve housing and the shock absorber cylinder, and the interior of the valve housing is hollow to form an airflow channel. An elastic valve core is fixedly installed on the inner wall of the valve housing by positioning screws, wherein the elastic valve core is located in the inner cavity of the sealed air chamber. The outer wall of the elastic valve core is provided with an elastic lip, and the outer wall of the elastic lip is provided with a conical sealing part, wherein the conical sealing part is fitted to the inner wall of the valve body for sealing. A vent hole is provided on the outer wall of the valve housing. The elastic lip abuts against the vent hole to elastically seal the air chamber. A removable plug is threaded to the port of the vent hole. A sealing O-ring is movably provided on the inner wall of the port of the vent hole, and the removable plug abuts against the sealing O-ring for fixation.

[0012] As a preferred embodiment of the present invention, the floating piston assembly includes a floating piston component, on the outer wall of the floating piston component, a sealing groove and a limiting groove are sequentially formed from top to bottom, and a rigid sealing ring is inserted and removed from the inner wall of the sealing groove.

[0013] As a preferred embodiment of the present invention, the inner wall of the limiting groove is provided with a connecting hole in an annular shape, and the connecting hole is provided in multiple sets and is located on the inner wall of the limiting groove respectively.

[0014] As a preferred embodiment of the present invention, an air injection groove is provided on the bottom outer wall of the floating piston component, and the connection between the air injection groove and the connecting hole is a connecting structure.

[0015] As a preferred embodiment of the present invention, an elastic ejection ring block is movably disposed on one side of the connecting hole and on the inner wall of the limiting groove, and the cross-section of the elastic ejection ring block is a concave shape.

[0016] As a preferred embodiment of the present invention, a rubber sealing block is movably provided on one side of the elastic ejector ring block and at the port of the limiting groove, and one end of the rubber sealing block slides against the inner wall of the shock absorber cylinder.

[0017] As a preferred embodiment of the present invention, the rubber sealing block is located on one side of the rigid sealing ring, the floating piston is located between the oil chamber valve core and the elastic valve core, the air injection groove is located on one side of the sealed air chamber, and the air injection groove and the sealed air chamber are connected.

[0018] As a preferred embodiment of the present invention, the air injection groove is directly opposite the elastic valve core, a lifting ring is fixedly installed on the bottom outer wall of the shock absorber cylinder, the valve housing is screwed onto the bottom of the shock absorber cylinder or the air storage end cap for fastening, and the port of the vent is an air filling hole.

[0019] Compared with existing technologies, this invention achieves a self-pre-tightening elastic seal for inflation by setting an inflation valve assembly in the inflation structure of a nitrogen shock absorber with a self-pre-tightening elastic valve core. By aligning the nitrogen gun connector with the removable plug, the high-pressure nitrogen gun is directed to the inflation port of the vent hole for inflation, thereby overcoming the elasticity of the rubber of the elastic lip and opening the conical sealing part of the elastic valve core to allow high-pressure nitrogen to enter the sealed gas chamber. After inflation is completed, the elastic lip automatically resets, the elastic valve core elastically closes the seal, and the removable plug with sealing effect is screwed in to increase the sealing security. This solves the problems of redundant nitrogen shock absorber inflation valve structure, expensive matching inflation equipment, and the inability to replenish nitrogen after sale due to the fact that most are one-time sealed.

[0020] This invention achieves elastic sealing of the floating piston by incorporating a floating piston assembly into the inflation structure of a nitrogen shock absorber with a self-pre-tightening elastic valve core. When the piston rod bears impact force, the piston rod end pushes the oil chamber valve core component downward along the inner wall of the shock absorber cylinder. The oil chamber valve core component squeezes the damping oil in the chamber, pushing the floating piston component downward. Simultaneously, the downward movement of the floating piston component compresses the nitrogen in the sealed gas chamber. The compressed nitrogen enters the limiting groove through the injection groove and connecting hole. The nitrogen pressure drives the elastic ejector ring block to apply pressure outward, pushing the rubber sealing block against the inner wall of the cylinder to achieve sealing. The floating piston assembly relies on the rigid sealing ring and the rubber sealing block to jointly improve the sealing performance. Even if the sealing components of the floating piston assembly experience wear under stress, the rubber sealing block, which expands under pressure, can still adhere to the inner wall of the cylinder to maintain the sealing effect. This solves the problems of the floating piston reciprocating within the cylinder, easily causing uneven wear under lateral force, rapid wear of the sealing ring, and nitrogen leakage; nitrogen leakage leads to a decrease in pre-pressure, insufficient shock absorber support, and vehicle body sagging.

[0021] This invention achieves elastic limiting of the floating piston by setting a floating piston assembly in the inflation structure of a nitrogen shock absorber with a self-pre-tightening elastic valve core. The floating piston compresses the nitrogen in the sealed air chamber under the push of the damping oil, and the nitrogen pressure gradually increases. The high-pressure nitrogen enters the limiting groove through the injection groove and the connecting hole, and then gradually pressurizes and squeezes the elastic ejector ring to expand outward. After the concave elastic ejector ring expands, it pushes the rubber sealing block, so that the rubber sealing block is pressed tightly against the inner wall of the shock absorber cylinder to achieve a buffering effect. This solves the problem of not being able to simultaneously achieve comfort at low speeds with small bumps and support at high speeds with large impacts. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the structural cross-section of the cylinder of the shock absorber of the present invention; Figure 3 This is a schematic diagram of the floating piston component structure of the present invention; Figure 4 This is a schematic diagram of the valve housing structure of the present invention; Figure 5 This is a schematic diagram illustrating the structural cross-section of the floating piston assembly of the present invention; Figure 6 This is the overall cross-sectional structure of the shock absorber cylinder of the present invention; Figure 7 For the present invention Figure 6 Enlarged schematic diagram of the structure at point A; Figure 8 For the present invention Figure 6 Enlarged schematic diagram of the structure at point B.

[0023] In the diagram: 1. Shock absorber cylinder; 2. Piston rod; 3. Oil chamber valve core; 4. Inflation valve assembly; 401. Valve housing; 402. Sealed air chamber; 403. Positioning screw; 404. Elastic valve core; 405. Conical sealing part; 406. Elastic lip; 407. Vent hole; 408. Removable plug; 409. Sealing O-ring; 5. Floating piston assembly; 501. Floating piston; 502. Sealing groove; 503. Limiting groove; 504. Rigid sealing ring; 505. Connecting hole; 506. Inflation groove; 507. Elastic ejection ring block; 508. Rubber sealing block; 6. Lifting ring. Detailed Implementation

[0024] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0025] Example: Please refer to Figure 1-8 The nitrogen damper inflation structure shown includes a damper cylinder 1, a piston rod 2 slidably connected to the port of the damper cylinder 1, and an oil chamber valve core 3 fixedly installed on one end of the piston rod 2 extending to the inner wall of the damper cylinder 1. The bottom outer wall of the shock absorber cylinder 1 is provided with an air valve assembly 4 for air-inflated self-pre-tightening elastic sealing, and the inner wall of the shock absorber cylinder 1 is provided with a floating piston assembly 5 for elastic limiting. In this embodiment, specific references Figure 1 , Figure 2 , Figure 4 , Figure 5 , Figure 6 and Figure 8 The inflation valve assembly 4 includes a valve housing 401, which is screwed onto the bottom of the shock absorber cylinder 1 for fastening. A sealed air chamber 402 is formed between the valve housing 401 and the shock absorber cylinder 1, and the interior of the valve housing 401 is hollow to form an airflow channel. An elastic valve core 404 is fixedly installed on the inner wall of the valve housing 401 by a positioning screw 403, wherein the elastic valve core 404 is located in the inner cavity of the sealed air chamber 402. The outer wall of the elastic valve core 404 is provided with an elastic lip 406, and the outer wall of the elastic lip 406 is provided with a conical sealing part 405, wherein the conical sealing part 405 is fitted to the inner wall of the valve body 401 for sealing. A vent hole 407 is provided on the outer wall of the valve body 401. An elastic lip 406 abuts against the vent hole 407 to elastically seal the sealed air chamber 402. A removable plug 408 is threadedly connected to the port of the vent hole 407. A sealing O-ring 409 is movably provided on the inner wall of the port of the vent hole 407, and the removable plug 408 abuts against the sealing O-ring 409 for fixation.

[0026] In this embodiment, specific references Figure 1 , Figure 2 , Figure 3 , Figure 5 , Figure 6 and Figure 7 The floating piston assembly 5 includes a floating piston component 501. A sealing groove 502 and a limiting groove 503 are sequentially formed on the outer wall of the floating piston component 501 from top to bottom. A rigid sealing ring 504 is inserted and removed from the inner wall of the sealing groove 502. A connecting hole 505 is formed in an annular pattern on the inner wall of the limiting groove 503. Multiple sets of connecting holes 505 are provided and located on the inner wall of the limiting groove 503. An air injection groove 506 is formed on the bottom outer wall of the floating piston component 501. The connection between the air injection groove 506 and the connecting hole 505 is a connecting structure. An elastic ejection ring block 507 is movably disposed on one side of the connecting hole 505 and on the inner wall of the limiting groove 503. The cross-section of the elastic ejection ring block 507 is concave. A rubber sealing block 508 is movably disposed on one side of the elastic ejection ring block 507 and at the port of the limiting groove 503. One end of the rubber sealing block 508 slides against the inner wall of the shock absorber cylinder 1.

[0027] Among them, the rubber sealing block 508 is located on one side of the rigid sealing ring 504, the floating piston 501 is located between the oil chamber valve core 3 and the elastic valve core 404, the air injection groove 506 is located on one side of the sealed air chamber 402, and the air injection groove 506 and the sealed air chamber 402 are connected.

[0028] Based on the above structural features and connection relationships, traditional inflation valves usually require springs, steel balls, snap rings, multi-stage guide sleeves, and multiple O-rings (≥5-8 pieces), while this invention only uses three core parts: liquid storage tank base + integrated elastic valve core 404 + screw plug, eliminating all metal springs and easily damaged seals, reducing assembly time by more than 80%. Existing technologies rely on expensive specialized nitrogen filling guns, pressure reducing valves, and pressure-holding fixtures. This invention utilizes an elastic colloid design, allowing for direct inflation by simply aligning the filling connector of a standard gas source (or a simple nitrogen filling gun) with the screw plug hole, directly opening the valve core. No complex gas circuit control is required, enabling low-cost operation in the field or at after-sales service centers. Traditional bottom covers are mostly one-time structures that are riveted or welded, and once the air pressure decreases, they can only be scrapped. The present invention features a liquid storage cylinder seat body connected to a flexible valve core with a 404 thread. The valve core can be repeatedly disassembled and reassembled with the screw plug, supporting ≥200 refills, which greatly extends the service life of the shock absorber and conforms to the concept of circular economy. The elastic lip, made of high-performance engineering plastics such as PEEK, has a coefficient of thermal expansion greater than that of metal. Under high-temperature conditions, the elastic lip expands radially, automatically increasing the clamping force and effectively compensating for material creep, thus preventing hot air leakage. At low temperatures, it shrinks but does not affect the pressure retention of the air cavity, solving the problems of easy aging of rubber seals and easy fatigue of metal springs. By replacing the traditional complex "multi-piece stacked valve" with a "single-piece self-pre-tightening elastic valve core 404" and integrating the inflation port into the bottom of the shock absorber, a significant reduction in manufacturing costs and an improvement in maintenance convenience have been achieved.

[0029] Among them, the air injection groove 506 is directly opposite the elastic valve core 404, the bottom outer wall of the shock absorber cylinder 1 is fixedly installed with a lifting ring 6, the valve body 401 is screwed to the bottom of the shock absorber cylinder 1 or the air storage end cap for fastening, and the port of the vent 407 is the air filling hole.

[0030] This solution features a nitrogen damper inflation structure with a self-pre-tightening elastic valve core. During operation, by aligning the nitrogen gun connector with the removable plug 408, the high-pressure nitrogen gun is directed to the inflation port of the vent 407 for inflation. This overcomes the elasticity of the rubber on the elastic lip 406, thereby opening the conical sealing part 405 of the elastic valve core 404 to allow high-pressure nitrogen to enter the sealed gas chamber 402. After inflation is complete, the elastic lip 406 automatically resets, and the elastic valve core 404 elastically closes the seal. Simultaneously, the removable plug 408, which provides a sealing effect, is screwed in to increase the sealing security. This solves the problems of redundant nitrogen damper inflation valve structure, expensive supporting inflation equipment, and the inability to replenish nitrogen after sales due to the often one-time sealing. When the piston rod 2 is subjected to an impact force, one end of the piston rod 2 pushes the oil chamber valve core 3 to move, which in turn causes the oil chamber valve core 3 to move downward on the inner wall of the damper cylinder 1. The oil chamber valve core 3 squeezes the damping oil in the inner cavity of the damper cylinder 1 downward, which in turn pushes the floating piston 501 downward. At the same time, when the floating piston 501 moves downward, it squeezes and compresses the nitrogen in the inner cavity of the sealed gas chamber 402. Simultaneously, the nitrogen in the inner cavity of the sealed gas chamber 402 enters the gas injection groove 506, and then the nitrogen is injected into the limiting groove 503 through the gas injection groove 506 and the connecting hole 505, so that the... Compressed nitrogen gas forces the elastic ejector ring 507 outward, which in turn pushes the rubber sealing block 508 against the inner wall of the shock absorber cylinder 1 for sealing. The floating piston assembly 5, with the rigid sealing ring 504 and the rubber sealing block 508 working together, achieves better sealing. When the seal of the floating piston assembly 5 is worn under force, the expanded rubber sealing block 508 can also adhere to the inner wall of the shock absorber cylinder 1 for sealing. This solves the problems of the floating piston reciprocating in the cylinder and being prone to uneven wear under lateral force, rapid wear of the sealing ring, and nitrogen leakage. Nitrogen leakage leads to a decrease in pre-pressure, insufficient shock absorber support, and vehicle body sagging. The compressed nitrogen gas forces the elastic ejector ring 507 outward, causing it to push the rubber sealing block 508 against the inner wall of the damper cylinder 1. The oil chamber valve core 3 forces the damping oil in the damper cylinder 1 downward, pushing the floating piston 501. This, in turn, compresses the nitrogen in the sealed gas chamber 402, causing the nitrogen pressure to gradually increase. As the nitrogen is injected into the limiting groove 503 through the injection groove 506 and connecting hole 505, the compressed nitrogen further forces the elastic ejector ring 507 outward, gradually increasing its pressure. This causes the concave elastic ejector ring 507 to expand and compress the rubber sealing block 508, which then presses against the inner wall of the damper cylinder 1 for cushioning. This solves the problem of simultaneously achieving both low-speed, small-bump comfort and high-speed, large-impact support.

[0031] All standard parts used in this application can be purchased from the market. The specific connection methods of each part adopt conventional methods such as bolts, rivets, and welding that are mature in the prior art. The machinery, parts and equipment adopt conventional models in the prior art and are also general components, which are common knowledge in this field.

[0032] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A nitrogen damper inflation structure with a self-preloaded elastic valve core, comprising a damper cylinder (1), characterized in that: A piston rod (2) is slidably connected to the port of the damper cylinder (1), and one end of the piston rod (2) extends to the inner wall of the damper cylinder (1) where an oil chamber valve core (3) is fixedly installed. The bottom outer wall of the shock absorber cylinder (1) is provided with an air valve assembly (4) for air-inflated self-tightening elastic sealing, and the inner wall of the shock absorber cylinder (1) is provided with a floating piston assembly (5) for elastic limiting. The inflation valve assembly (4) includes a valve housing (401), which is screwed onto the bottom of the shock absorber cylinder (1) for fastening. A sealed air chamber (402) is formed between the valve housing (401) and the shock absorber cylinder (1), and the valve housing (401) is hollow inside to form an airflow channel. An elastic valve core (404) is fixedly installed on the inner wall of the valve housing (401) by a positioning screw (403), wherein the elastic valve core (404) is located in the inner cavity of the sealed air chamber (402). The outer wall of the elastic valve core (404) is provided with an elastic lip (406), and the outer wall of the elastic lip (406) is provided with a conical sealing part (405), wherein the conical sealing part (405) is fitted to the inner wall of the valve body (401) for sealing; A vent hole (407) is provided on the outer wall of the valve housing (401). The elastic lip (406) abuts against the vent hole (407) to elastically seal the sealed air chamber (402). A removable plug (408) is threadedly connected to the port of the vent hole (407). A sealing O-ring (409) is movably provided on the inner wall of the port of the vent hole (407), and the removable plug (408) abuts against the sealing O-ring (409) for fixation.

2. The inflation structure for a nitrogen damper with a self-preloaded elastic valve core according to claim 1, characterized in that: The floating piston assembly (5) includes a floating piston component (501). A sealing groove (502) and a limiting groove (503) are sequentially opened on the outer wall of the floating piston component (501) from top to bottom. A rigid sealing ring (504) is inserted and installed on the inner wall of the sealing groove (502).

3. The inflation structure for a nitrogen damper with a self-preloaded elastic valve core according to claim 2, characterized in that: The inner wall of the limiting groove (503) is provided with a ring-shaped connecting hole (505), and there are multiple sets of connecting holes (505) located on the inner wall of the limiting groove (503).

4. The inflation structure for a nitrogen damper with a self-preloaded elastic valve core according to claim 3, characterized in that: The bottom outer wall of the floating piston component (501) is provided with an air injection groove (506), and the connection between the air injection groove (506) and the connecting hole (505) is a connecting structure.

5. The inflation structure for a nitrogen damper with a self-preloaded elastic valve core according to claim 4, characterized in that: An elastic ejection ring block (507) is movably disposed on one side of the connecting hole (505) and on the inner wall of the limiting groove (503). The cross-section of the elastic ejection ring block (507) is a concave shape.

6. The inflation structure for a nitrogen damper with a self-preloaded elastic valve core according to claim 5, characterized in that: A rubber sealing block (508) is movably disposed on one side of the elastic ejector ring (507) and at the port of the limiting groove (503). One end of the rubber sealing block (508) slides against the inner wall of the shock absorber cylinder (1).

7. The inflation structure for a nitrogen damper with a self-preloaded elastic valve core according to claim 6, characterized in that: The rubber sealing block (508) is located on one side of the rigid sealing ring (504), the floating piston (501) is located between the oil chamber valve core (3) and the elastic valve core (404), the air injection groove (506) is located on one side of the sealed air chamber (402), and the air injection groove (506) and the sealed air chamber (402) are connected.

8. The inflation structure for a nitrogen damper with a self-preloaded elastic valve core according to claim 4, characterized in that: The air injection groove (506) is directly opposite the elastic valve core (404). A lifting ring (6) is fixedly installed on the bottom outer wall of the damper cylinder (1). The valve housing (401) is screwed onto the bottom of the damper cylinder (1) or the air storage end cap for fastening. The port of the vent (407) is the air filling hole.

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