Mechanical double-chamber air spring

Abstract

The present invention belongs to the technical field of automobile air springs, specifically relating to a mechanical dual-chamber air spring comprising a top seat, a bladder, a piston, and a shock absorber assembly. The top end of the bladder is sealedly connected to the top seat, and the bottom end of the bladder is sealedly connected to the piston. The top seat, bladder, and piston form a sealed main chamber. The shock absorber assembly comprises a shock absorber sleeve and a telescopic rod. A secondary chamber is provided within the piston, and the main and secondary chambers are connected via an air duct. The telescopic rod passes through the secondary chamber, the air duct, and the main chamber and is connected to the top seat. A sealing plug is provided in the main chamber, which moves with the top seat, and the sealing plug and the air duct form a sealing structure. The influence of road conditions on the upward and downward telescopic movement of the piston is used to control the timing of the sealing plug's sealing connection with the air duct, thereby achieving rapid switching between the connected and isolated states of the main and secondary chambers, changing the volume of the air spring's effective chamber, and quickly and efficiently adjusting the air spring's stiffness, thereby improving driving comfort and saving costs.

Description

Technical Field

[0001] The invention belongs to the technical field of automobile air springs, and in particular relates to a mechanical double-cavity air spring. Background Art

[0002] An air spring is a spring that uses compressed air as an elastic medium. Its working principle is to use the compressibility of air to achieve elastic action. Air springs have excellent nonlinear characteristics and can provide relatively stable support for the vehicle body. They are widely used in the suspension systems of various vehicles. The stiffness of the air spring has an important impact on the comfort and handling stability of the vehicle. An air spring generally includes a top seat, a bladder, a piston and a shock absorber assembly. The upper end of the bladder is sealed to the top seat, and the lower end of the bladder is sealed to the piston. The top seat, bladder and piston form a closed main chamber. The shock absorber includes a shock absorber sleeve connected to the piston and a telescopic rod telescopically connected to the shock absorber sleeve. The telescopic rod is generally connected to the top seat. When the vehicle is on a bad road, the vehicle will bump up and down and shake violently. The original stiffness of the air spring is insufficient and cannot provide enough support for the vehicle body. It is very easy to cause the telescopic rod and shock absorber sleeve of the shock absorber assembly in the air spring to bottom out and collide, thereby causing the air suspension and vehicle body to be impacted, affecting driving comfort and even causing damage to the shock absorber and the entire air spring.

[0003] Existing technologies often employ elastic cushions within the air spring's gas chamber to prevent the shock absorber assembly's telescopic rod from directly bottoming out. When road conditions are poor and the air spring's stiffness is insufficient, the cushion compresses and deforms upon impact, cushioning the shock absorber's telescopic rod or sleeve. This prevents the rod from directly bottoming out, reduces the impact force on the air suspension and vehicle body, and improves driving comfort. However, excessive impact forces on the cushion can still cause significant discomfort to vehicle occupants. Furthermore, the cushion is susceptible to damage after repeated impacts, necessitating frequent maintenance and replacement, which wastes manpower.

[0004] In order to further ensure the comfort of the vehicle under harsh road conditions, some air springs adjust their stiffness by setting an air cavity with adjustable volume. For example, the Chinese invention patent with publication number CN216478633U discloses a dual-chamber air spring, which records a main chamber and a sub-chamber separated from each other. By setting a solenoid valve to control whether the main and sub-chambers are connected, the volume of the effective action chamber can be adjusted, thereby achieving the stiffness adjustment of the air spring. For example, when the vehicle is traveling on a section of road with bad road conditions, the solenoid valve is closed to isolate the main chamber and the sub-chamber from each other. At this time, the effective action chamber is the main chamber, which reduces the volume of the effective action chamber and increases the stiffness of the air spring. The solenoid valve in this solution is generally controlled by the on-board computer, and the two are connected in communication. This requires the addition of relevant signal lines and components, which is complex in structure, requires a large installation space, and greatly increases the cost. In addition, it takes about 0.3 to 0.5 seconds from manually operating the on-board computer, the on-board computer sending a signal to the solenoid valve, the solenoid valve executing the action after receiving the signal, and then the action is completed. If the solenoid valve does not act in time, it will still cause the shock absorber telescopic rod to bottom out. This stiffness switching method also increases the vehicle's energy consumption. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a mechanical dual-chamber air spring, which can adjust the stiffness of the air spring by quickly switching the volume of the effective air chamber of the air spring, has a simple structure and saves costs.

[0006] The technical solution adopted by the present invention to solve this technical problem is: a mechanical dual-chamber air spring, comprising a top seat, a bladder skin, a piston and a shock absorber assembly, wherein the upper end of the bladder skin is sealedly connected to the top seat, and the lower end of the bladder skin is sealedly connected to the piston, and the top seat, the bladder skin and the piston form a closed main chamber; the shock absorber assembly comprises a shock absorber sleeve and a telescopic rod;

[0007] A secondary chamber is provided in the piston, and the main chamber and the secondary chamber are connected through an air duct; the telescopic rod passes through the secondary chamber, the air duct and the main chamber and is connected to the top seat;

[0008] A sealing plug is provided in the main chamber and moves with the top seat, and the sealing plug forms a sealing structure with the air duct.

[0009] Furthermore, the sealing plug is installed on the top seat or the telescopic rod.

[0010] Furthermore, the sealing plug includes a plunger body and a supporting ring plate, and an elastic sealing ring adapted to the inner diameter of the air duct is provided on the outer periphery of the supporting ring plate.

[0011] Furthermore, the plunger body is provided with an axial through hole, and the telescopic rod passes through the axial through hole of the plunger body and is fixedly connected to the plunger body;

[0012] The top seat is provided with a clamping groove, and the plunger body is clamped and installed in the clamping groove.

[0013] Furthermore, the sealing ring is made of nitrile rubber.

[0014] Furthermore, a pressure plate is provided at the telescopic end of the telescopic rod, and a buffer pad is provided between the shock absorber sleeve and the pressure plate;

[0015] The top seat is the pressure plate, and the plunger body is the buffer pad.

[0016] Furthermore, a sealing sleeve is provided in the sub-chamber, and a protruding limiting portion is provided on the outer peripheral surface of the sealing sleeve, the limiting portion overlaps the top surface of the piston, and the outer wall of the sealing sleeve is sealed with the inner wall of the sub-chamber; the inner cavity of the sealing sleeve is the air duct.

[0017] Furthermore, the upper end of the inner wall of the sealing sleeve is provided with a guide slope arranged upwardly and obliquely from the inside to the outside, and the lower end of the sealing ring is provided with an outward convex guide arc surface arranged upwardly and obliquely from the inside to the outside.

[0018] Furthermore, the inner circumference of the sealing sleeve is covered with a self-lubricating coating, and the sealing ring is made of a self-lubricating material.

[0019] Compared with the prior art, the beneficial effects of the present invention are: providing a mechanical dual-chamber air spring, which connects the main chamber and the sub-chamber by arranging an air duct, and changes the volume of the effective action chamber of the air spring by arranging a sealing plug and controlling the matching state of the sealing plug and the air duct, thereby realizing the stiffness adjustment of the air spring; according to the movement law that the ruggedness of the driving road condition is positively correlated with the up and down telescopic movement amplitude of the piston relative to the top seat, the up and down telescopic amplitude of the piston itself is used to automatically control the matching state of the sealing plug and the air duct, thereby realizing timely switching of the connection / isolation state of the main chamber and the sub-chamber, and timely switching of the volume of the effective action chamber of the air spring, realizing fast and efficient stiffness adjustment of the air spring, improving driving comfort and stability, saving vehicle energy consumption, saving manpower, and increasing the service life of the air spring; in addition, the present invention has a simple structure, does not require additional wiring and other electronic control components, and saves installation space. The present invention also uses a buffer pad to avoid the rigid collision between the telescopic rod and the shock absorber sleeve when the air spring stiffness is adjusted to the maximum value and still cannot meet the driving requirements, thereby further improving the driving stability and comfort under harsh road conditions, increasing the service life of the shock absorber assembly and the air spring as a whole, and ensuring driving safety. By providing a sealing ring instead of a sealing plug to be directly sealed and connected to the side wall of the air duct, and by providing a sealing sleeve instead of a piston to be directly sealed and connected to the sealing plug, only the sealing ring and the sealing sleeve need to be replaced after wear, which is convenient for processing and manufacturing, convenient for maintenance, and saves costs. By coating the inner wall of the sealing sleeve with a self-lubricating coating and setting the sealing ring as a self-lubricating sealing ring, the relative sliding smoothness between the sealing plug and the side wall of the air duct is ensured, the wear of the sealing plug and the outer wall of the air duct is slowed down, and the service life of the air spring is extended. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic cross-sectional view of the main chamber and the auxiliary chamber of the present invention in a state of being interconnected;

[0021] Figure 2 It is a schematic cross-sectional view of an embodiment of the present invention in which the main chamber and the sub-chamber are isolated from each other;

[0022] Figure 3 This is a schematic cross-sectional view of the present invention's buffering pad in a buffering state for the shock absorber sleeve and the telescopic rod;

[0023] Figure 4 for Figure 1 A schematic diagram of the enlarged structure of the middle part A;

[0024] Figure 5 for Figure 2 A schematic diagram of the enlarged structure of the middle part B;

[0025] Figure 6 for Figure 3 Schematic diagram of the enlarged structure of the middle C part;

[0026] Figure markings: 1-top seat; 2-bladder skin; 3-piston; 4-shock absorber assembly; 41-shock absorber sleeve; 42-telescopic rod; 43-pressure plate; 51-main chamber; 52-sub-chamber; 6-sealing plug; 61-plunger body; 62-sealing ring; 63-support ring plate; 64-guide arc surface; 7-ventilation channel; 71-sealing sleeve; 72-limiting ring plate; 73-guide slope; 8-buffer pad. DETAILED DESCRIPTION

[0027] The present invention will be further described below with reference to the accompanying drawings and examples.

[0028] As attached Figure 1-6 As shown, a mechanical double-chamber air spring includes a top seat 1, a bladder skin 2, a piston 3 and a shock absorber assembly 4, the upper end of the bladder skin 2 is sealed and connected to the top seat 1, and the lower end of the bladder skin 2 is sealed and connected to the piston 3, and the top seat 1, the bladder skin 2 and the piston 3 form a closed main chamber 51; the shock absorber assembly 4 includes a shock absorber sleeve 41 and a telescopic rod 42; a sub-chamber 52 is provided in the piston 3, and the main chamber 51 is connected to the sub-chamber 52 through an air duct 7; the telescopic rod 42 passes through the sub-chamber 52, the air duct 7 and the main chamber 51 and is connected to the top seat 1; a sealing plug 6 is provided in the main chamber 51 and moves with the top seat 1, and the sealing plug 6 forms a sealing structure with the air duct 7.

[0029] When the vehicle is driving, the roughness of the road surface is positively correlated with the amplitude of the up and down movement of the piston 3 relative to the top seat 1. When the roughness of the road surface increases, the amplitude of the up and down movement of the piston 3 increases under the action of the convex part of the road surface. Figure 1 and Figure 4 As shown, when the vehicle is traveling on a relatively flat road and the piston 3's upward and downward telescopic movement is less than a preset value, the sealing plug 6 is always located in the main chamber 51 outside the vent 7. The sealing plug 6 is spaced apart from the vent 7, and the main chamber 51 and the sub-chamber 52 are connected through the vent 7. At this time, the main chamber 51 and the sub-chamber 52 that are connected to each other are both effective working chambers of the air spring. Figure 2 and attached Figure 5As shown, when the vehicle enters a rough road section and the relative upward and downward expansion and contraction range of the piston 3 exceeds the preset value, the original stiffness of the air spring can no longer meet the vehicle's support needs at this time. The piston 3 and the top seat 1 approach each other, and the top seat 1 drives the sealing plug 6 to enter the air duct 7 of the piston 3 to block the air duct 7. The side wall of the piston 3 is sealed with the side wall of the air duct 7 to separate the main chamber 51 and the sub-chamber 52. At this time, the effective action chamber of the air spring is mainly the main chamber 51 above the sealing plug 6, which reduces the volume of the effective action chamber of the air spring, increases the stiffness of the air spring, and meets the vehicle's support needs at this time. The volume of the effective action chamber is reduced by the volume of the sub-chamber 52 located below the sealing plug 6. The above-mentioned "preset value" refers to the distance between the sealing plug 6 and the air duct 7 when the vehicle is stationary. The air spring of the present invention can obtain different stiffness curves by changing the volume ratio of the main chamber 51 and the sub-chamber 52.

[0030] The present invention connects the main chamber 51 with the sub-chamber 52 by providing an air duct 7, and switches the main chamber 51 and the sub-chamber 52 between the connected / isolated state by providing a sealing plug 6 and controlling the matching state of the sealing plug 6 and the air duct 7, thereby changing the volume of the effective action chamber of the air spring and adjusting the stiffness of the air spring. The present invention automatically controls the timing of sealing the air duct 7 by using the up-and-down telescopic movement of the piston 3 relative to the top seat 1, according to the motion law that the roughness of the road condition is positively correlated with the amplitude of the piston 3 relative to the top seat 1, thereby achieving timely switching of the connected / isolated state of the main chamber 51 and the sub-chamber 52 and the volume of the effective action chamber of the air spring, and quickly and efficiently adjusting the stiffness of the air spring, thereby improving driving comfort and stability, saving vehicle energy consumption, saving manpower, avoiding damage to the air spring caused by the shock absorber bottoming out, and increasing the service life of the air spring. In addition, the present invention has a simple structure and does not require additional wiring and other electronic control components, thus saving installation space.

[0031] The top seat 1 is used to connect the air spring to the suspension and enable the air spring to support the vehicle body. The top seat 1 can be a columnar structure or a cylindrical structure with a sealed top. Generally, the inflation port of the main chamber 51 is set on the top seat 1, and an opening and closing valve can be provided on the inflation port to control the opening and closing of the inflation port. The piston 3 is used to connect the lower end of the air spring to the wheel axle, and it can move up and down synchronously with the wheel axle. The piston 3 can be a cylindrical structure with a uniform cross-section or a cylindrical structure with a variable cross-section. It can be an integrally formed whole or assembled from multiple parts. The bladder skin 2 is generally connected to the top seat 1 and the piston 3 by a clamp.

[0032] The sealing plug 6 is used to control the conduction of the air duct 7 in the piston 3. The sealing plug 6 can be installed on the top seat 1 by means of clamping, hoop connection, bolt connection, etc., and can also be installed on the telescopic rod 42. The sealing plug 6 is generally configured as a compressible flexible structure, which can be an integral structure formed in one piece, or a combined structure assembled from multiple parts. The sealing plug 6 is generally a plunger structure, which can be a plunger of equal cross-section or a plunger of variable cross-section. Considering that the relative sliding between the sealing plug 6 and the outer wall of the air duct 7 is prone to wear of the contact surface, it is time-consuming and labor-intensive to replace the piston 3 and the sealing plug 6 as a whole after wear occurs. Preferably, the sealing plug 6 includes a plunger body 61 and a support ring plate 63, and the outer periphery of the support ring plate 63 is provided with an elastic sealing ring 62 adapted to the inner diameter of the air duct 7. The "elastic sealing ring 62 adapted to the inner diameter of the vent 7" refers to the fact that when the sealing plug 6 blocks the vent 7, the plunger body 61, support ring plate 63, and sealing ring 62 are all located within the vent 7. The sealing ring 62 is elastically deformed by the compression of the support ring plate 63 and the sidewall of the vent 7, forming a sealed connection with the sidewall of the vent 7. As the sealing plug 6 moves in and out of the vent, the sealing ring 62 slides directly into the vent. When worn, only the sealing ring 62 needs to be replaced, facilitating maintenance and saving costs.

[0033] The plunger body 61 is used to mount the sealing plug 6 on the top seat 1 or the telescopic rod 42. Preferably, the plunger body 61 is provided with an axial through-hole, through which the telescopic rod 42 extends and is fixedly connected to the plunger body 61. The top seat 1 is provided with a slot, into which the plunger body 61 is snap-fitted. As the sealing plug 6 moves in and out of the airway 7, the telescopic rod 42 acts as a guide and limiter, ensuring the relative movement direction of the sealing plug 6 and the airway 7.

[0034] The support ring plate 63 is used to support the sealing ring 62, increase its rigidity, ensure a sealed connection between the sealing ring 62 and the outer wall of the air passage 7, and improve the quality of the air spring stiffness adjustment. The support ring plate 63 and the plunger body 61 can be a combined structure fixedly assembled via a connector, or they can be an integrally molded structure. The sealing ring 62 is generally made of a rubber elastic material. As a further preference, the sealing ring 62 is made of nitrile rubber, which has excellent oil resistance, wear resistance, and heat resistance. The sealing ring 2 can be fixedly mounted on the support ring plate 63 after vulcanization.

[0035] The shock absorber assembly 4 mainly provides motion guidance for the air spring and provides support and protection for the air spring. When the stiffness of the above-mentioned air spring is adjusted to the maximum value and still cannot meet the driving needs, the shock absorber assembly 4 is subjected to excessive impact force, and the telescopic rod 42 is very likely to rigidly collide with the shock absorber sleeve 41 after retraction. Preferably, a pressure plate 43 is provided at the telescopic end of the telescopic rod 42, and a buffer pad 8 is provided between the shock absorber sleeve 41 and the pressure plate 43. When the retraction stroke of the telescopic rod 42 is too large, the pressure plate 43 compresses the buffer pad 8, and the buffer pad 8 pushes the pressure plate 43 and the telescopic end of the telescopic rod 42 upward to avoid rigid collision between the telescopic rod 42 and the shock absorber sleeve 41, further improving driving stability and comfort under harsh road conditions, and increasing the service life of the shock absorber assembly 4 and the air spring as a whole, thereby ensuring driving safety. The buffer pad 8 can be installed on the shock absorber sleeve 41, the telescopic end of the telescopic rod 42, the pressure plate 43 or the piston 3. The material of the buffer pad 8 can be elastic materials such as silicone, rubber, polyurethane, etc.

[0036] As a further preference, the top seat 1 is the pressure plate 43, and the plunger body 61 is the buffer pad 8. The top seat 1 and the pressure plate 43 are set as a whole, and the plunger body 1 and the buffer pad 8 are designed as a whole, which simplifies the structure, facilitates processing and assembly, and saves manpower. Figure 3 and attached Figure 6 As shown, when the air spring is subjected to excessive impact force, the sealing plug 6 blocks the air passage 7, isolating the main chamber 51 from the auxiliary chamber 52. At the same time, the top seat 1 and the shock absorber sleeve 41 cooperate to squeeze the sealing plug 6 from above and below. The sealing plug 6 reacts on the top seat 1 and the shock absorber sleeve 41 to prevent the telescopic rod 42 connected to the top seat 1 from rigidly colliding with the shock absorber sleeve 41. The sealing plug 6 should be made of a compressible elastic material such as silicone, rubber, or polyurethane.

[0037] If the side wall of the air duct 7 and the piston 3 are an integrally formed structure, the piston 3 needs to be replaced as a whole after the side wall of the air duct 7 is worn. Preferably, a sealing sleeve 71 is provided in the sub-chamber 52, and an outwardly protruding limiting portion 72 is provided on the outer peripheral surface of the sealing sleeve 71. The limiting portion 72 overlaps the top surface of the piston 3, and the outer wall of the sealing sleeve 71 is sealed with the inner wall of the sub-chamber 52; the inner cavity of the sealing sleeve 71 is the air duct 7. After the outer wall of the air duct 7 is worn, only the sealing sleeve 71 needs to be replaced, which saves cost and manpower. In addition, the sealing sleeve 71 has a simple structure, and its inner wall processing is easier than that of the inner wall processing of the piston 3. The sealing sleeve 71 can be made of aluminum alloy, steel, plastic and other materials. It is generally installed in the piston 3 by press-fitting to ensure that it is sealed and connected to the piston 3.

[0038] To ensure that the sealing plug 6 can smoothly enter the vent 7, preferably, a guide slope 73 arranged upward and tilted from the inside to the outside is provided at the upper end opening of the inner wall of the sealing sleeve 71, and an outwardly convex guide arc surface 64 arranged upward and tilted from the inside to the outside is provided at the lower end of the sealing ring 62. The guide slope 73 can be an inclined plane or a radially inwardly convex arc surface.

[0039] In order to further delay the wear of the sealing plug 6 and the outer wall of the vent 7, it is necessary to reduce the sliding friction coefficient between the sealing ring 62 and the sealing sleeve 71 and improve the relative sliding smoothness between the two. This can be achieved through the following two embodiments:

[0040] Embodiment 1: The inner wall of the sealing sleeve 71 is covered with a self-lubricating coating.

[0041] Embodiment 2: The sealing ring 62 is made of a self-lubricating material.

[0042] Embodiments 1 and 2 can be combined or implemented separately. Specifically, when using embodiment 1, the sealing ring 62 can be made of a rubber-like material such as nitrile rubber, or a self-lubricating material. When using embodiment 2, the inner wall of the sealing sleeve 71 can be coated with a self-lubricating coating, or it can be left untreated. The self-lubricating material can be polytetrafluoroethylene, polyoxymethylene, polyamide, ultra-high molecular weight polyethylene, polyphthalimide, or the like.

[0043] The above is a specific embodiment of the present invention, which is intended to be used to explain the present invention and is not to be construed as limiting the present invention. In the description of the present invention, the terms "upper," "lower," "vertical," "horizontal," "top," "bottom," "inside," "outside," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate description and simplify the present invention. They do not indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore are not to be construed as limiting the present invention.

Claims

1. A mechanical double-chamber air spring, comprising a top seat (1), a bladder skin (2), a piston (3) and a shock absorber assembly (4), wherein the upper end of the bladder skin (2) is sealedly connected to the top seat (1), and the lower end of the bladder skin (2) is sealedly connected to the piston (3), and the top seat (1), the bladder skin (2) and the piston (3) enclose a closed main chamber (51); the shock absorber assembly (4) comprises a shock absorber sleeve (41) and a telescopic rod (42); and is characterized in that: A secondary chamber (52) is provided in the piston (3), and the main chamber (51) and the secondary chamber (52) are connected via an air duct (7); the telescopic rod (42) passes through the secondary chamber (52), the air duct (7) and the main chamber (51) to be connected to the top seat (1); A sealing plug (6) is provided in the main chamber (51) and moves with the top seat (1), and the sealing plug (6) and the air duct (7) form a sealing structure; The sealing plug (6) comprises a plunger body (61) and a supporting ring plate (63); an elastic sealing ring (62) adapted to the inner diameter of the air passage (7) is provided on the outer periphery of the supporting ring plate (63); An axial through hole is provided on the plunger body (61), and the telescopic rod (42) passes through the axial through hole of the plunger body (61) and is fixedly connected to the plunger body (61); The top seat (1) is provided with a slot, and the plunger body (61) is mounted in the slot; A sealing sleeve (71) is provided in the sub-chamber (52), and an outwardly protruding limiting portion (72) is provided on the outer peripheral surface of the sealing sleeve (71). The limiting portion (72) overlaps the top surface of the piston (3), and the outer wall of the sealing sleeve (71) is sealedly connected to the inner wall of the sub-chamber (52); the inner cavity of the sealing sleeve (71) is the air passage (7).

2. The mechanical dual-chamber air spring according to claim 1, characterized in that: The sealing ring (62) is made of nitrile rubber.

3. The mechanical dual-chamber air spring according to claim 1, characterized in that: A pressure plate (43) is provided at the telescopic end of the telescopic rod (42), and a buffer pad (8) is provided between the shock absorber sleeve (41) and the pressure plate (43); The top seat (1) is the pressure plate (43), and the plunger body (61) is the buffer pad (8).

4. The mechanical dual-chamber air spring according to claim 1, characterized in that: The upper end of the inner wall of the sealing sleeve (71) is provided with a guide slope surface (73) arranged upward and tilted from the inside to the outside, and the lower end of the sealing ring (62) is provided with an outward convex guide arc surface (64) arranged upward and tilted from the inside to the outside.

5. The mechanical dual-chamber air spring according to claim 1, characterized in that: The inner circumference of the sealing sleeve (71) is coated with a self-lubricating coating, and the sealing ring (62) is made of a self-lubricating material.

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