Air spring structure with flexible supporting piston

Abstract

The invention provides an air spring structure with a flexible supporting piston, which comprises a fluctuating piston and a shock absorber, a buckling tooth section is arranged at the upper part of the fluctuating piston, and a protective cover assembly is sleeved on the shock absorber, and is characterized in that the protective cover assembly comprises a protective cover which is of a cylindrical structure; a flexible supporting sleeve is arranged on the outer circle face of the protective cover in a sleeving mode, and the flexible supporting sleeve is in interference fit with the protective cover. A movable gap is formed between the outer side wall of the flexible supporting sleeve and the inner side wall of the buckling tooth section; a ventilation structure is arranged in the side wall of the buckling tooth section in the axial direction and penetrates through the side wall of the buckling tooth section. The problems that an existing shock absorber protection cover is high in structural brittleness, prone to fatigue failure, prone to causing abrasion to affect the service life of a shock absorber, high in cost and the like are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of air spring shock absorbers, and in particular to an air spring structure with a flexible supporting piston. Background Art

[0002] Due to their advantages of good adjustability, light weight, and high load capacity, air springs are increasingly being installed on front and rear suspensions. The protective cover is a key component of the air spring strut assembly. It is located inside the undulating piston and mounted on the upper end of the shock absorber. It protects the shock absorber from the intrusion of contaminants such as dust, which could degrade its performance and reliability. Typically, the protective cover is made of PA66+GF50 plastic, with multiple sets of reinforcing ribs evenly distributed along its outer circumference. The undulating piston cylinder is made of metal. Existing protective cover structures have the following drawbacks:

[0003] 1. Due to the characteristics of the protective cover material, when the alternating axial and radial loads of the shock absorber act directly on the protective cover, it is easy to cause cracks at the root of the reinforcing ribs. When the piston is working with large impact, the simultaneous radial load may accelerate the crack propagation and lead to fatigue failure. Once the protective cover is shattered by the impact of the collision, the resulting glass fiber debris and other debris will greatly deteriorate the working environment of the air spring shock absorber, seriously affecting the life and performance of the air spring shock absorber, and the replacement and maintenance process is complicated.

[0004] 2. Because glass fiber is much harder than the material of the spring piston, the engineering plastic material of the protective cover will wear out after long-term use. The exposed glass fiber will then rub against the spring piston and other components, causing noise. It will also cause scratches on the spring piston surface, exacerbating oxidation, shortening the life of the air spring and increasing the cost of air spring repair. Especially when the car is driven for a long time, the heat generated by the shock absorber may cause the protective cover to expand due to heat, increasing the probability of direct contact with other components, and the probability of wear and noise.

[0005] 3. It is detrimental to vehicle cost control, NVH control, and smooth ride quality. When the air spring is subjected to significant impact loads, the protective cover may frequently strike other components, generating noise and vibration. If the suspension continues to operate after the protective cover fails, the life and performance of the shock absorber and air spring will rapidly decrease, affecting vehicle smooth ride quality, generating unusual noises, and impacting the driving experience. Suspension components are more likely to fail, and the aluminum alloy heave piston is difficult to repair, increasing vehicle maintenance costs.

[0006] 4. The protective cover has high manufacturing costs. The protective cover material has a high glass fiber content, and the original design has reinforcing ribs on the outer surface of the protective cover, resulting in a complex structure. This leads to high requirements for injection molding and surface treatment processes during the protective cover manufacturing process, which is not conducive to the requirements of low cost and high pass rate of the product. Summary of the Invention

[0007] The purpose of the present invention is to provide a new air spring structure with a flexible support piston to solve the problems of the existing shock absorber protection cover structure being high in brittleness, prone to fatigue failure, prone to wear and tear affecting the life of the shock absorber, and high cost.

[0008] The technical solution adopted by the present invention to solve its technical problem is:

[0009] An air spring structure with a flexible support piston comprises an undulating piston and a shock absorber, wherein a buckling tooth segment is provided on the upper portion of the undulating piston, and a protective cover assembly is provided on the shock absorber. The invention is characterized in that the protective cover assembly comprises a protective cover, which is a cylindrical structure, and a flexible support sleeve is provided on the outer circumferential surface of the protective cover, and the flexible support sleeve and the protective cover have an interference fit; an active gap is provided between the outer wall of the flexible support sleeve and the inner wall of the buckling tooth segment; a ventilation structure is provided in the axial direction in the side wall of the buckling tooth segment, and the ventilation structure passes through the side wall of the buckling tooth segment.

[0010] Preferably, in combination with the above solution, the ventilation structure is ventilation holes evenly spaced along the circumference of the pressing tooth segment, and the ventilation holes axially penetrate the side wall of the pressing tooth segment.

[0011] Preferably, in combination with the above solution, at least two groups of ventilation holes are provided; and the ventilation holes are symmetrically arranged along the central axis of the pressing tooth segment.

[0012] Preferably, in combination with the above solution, the diameter of the vent hole is 2-4 mm.

[0013] Preferably, in combination with the above solution, the flexible support sleeve is made of self-lubricating rubber, and the thickness of the flexible support sleeve is 1.5-3 mm.

[0014] Preferably, in combination with the above solution, the interference between the flexible support sleeve and the protective cover is 0.1-0.3 mm.

[0015] Preferably, in combination with the above solution, the single-side gap between the outer side wall of the flexible support sleeve and the inner side wall of the pressing tooth segment is 1-2 mm.

[0016] Preferably, in combination with the above solution, a chamfered structure is provided on the inner side wall of the pressing tooth segment to facilitate assembly.

[0017] Preferably, in combination with the above solution, the height of the flexible support sleeve is smaller than the height of the protective cover, and the bottom of the flexible support sleeve is flush with the bottom of the protective cover.

[0018] Preferably, in combination with the above solution, the material of the protective cover is PA66+GF50 plastic, and the material of the undulating piston is 6082 aluminum alloy.

[0019] Beneficial effects of the present invention: The air spring structure with a flexible support piston of the present invention has the following advantages:

[0020] 1. An air spring with a flexible support protective cover assembly is used. Under the premise of ensuring that the original performance of the protective cover is not reduced and the weight of the overall structure is not excessively increased, the flexible support sleeve can absorb most of the axial and radial alternating loads, significantly reducing the alternating stress directly acting on the protective cover, reducing the possibility of fatigue failure, and extending the service life of the protective cover, indirectly reducing the failure rate of the shock absorber, and improving the reliability of the shock absorber.

[0021] 2. The simplified structure of the protective cover can simplify the process, which is beneficial to reducing process requirements and manufacturing hours, improving the yield rate and production efficiency, and reducing manufacturing costs.

[0022] 3. The flexible support sleeve can minimize the probability of the protective cover contacting other parts during movement, while providing a buffering effect, greatly reducing the collision and wear of various parts, and absorbing part of the impact load, thereby extending the service life and reliability and reducing the maintenance cost of the air spring.

[0023] 4. Since the failure of the protective cover cannot be detected immediately, even if cracks still appear on the protective cover after long-term use, the rubber support sleeve can still play a partial tightening role. The elastic force exerted on the outer wall of the protective cover can inhibit the expansion of the cracks and prevent dust and other pollutants from entering the shock absorber along the cracks as much as possible. To a certain extent, it can extend the life of the shock absorber, reduce the probability of premature damage to the shock absorber, and reduce maintenance costs.

[0024] 5. The addition of a rubber support sleeve significantly reduces the probability of collision between the rear cover and other components within the air spring shock absorber, improving the vehicle's NVH performance while extending the service life of the cover and other components, enhancing the driving experience. It also reduces the failure rate of suspension components, lowers vehicle maintenance costs, and extends maintenance cycles.

[0025] The present invention will be described in more detail below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The figure is a structural diagram of an existing protective cover.

[0027] Figure 2 This is a cross-sectional view of an air spring with a flexible support piston according to the present invention.

[0028] Figure 3 It is a cross-sectional view of the undulating piston in the present invention.

[0029] Figure 4 It is a top view of the undulating piston in the present invention.

[0030] Figure 5 This is a structural diagram of the protective cover assembly of the present invention.

[0031] Figure 6 It is a cross-sectional view of the protective cover assembly of the present invention.

[0032] Among them, 1. undulating piston; 2. shock absorber; 3. piston rod; 4. protective cover; 5. flexible support sleeve; 11. buckling tooth segment; 12. ventilation structure; 13. chamfer structure. DETAILED DESCRIPTION

[0033] like Figure 1 The existing protective cover shown is usually made of PA66+GF50 plastic, and multiple groups of reinforcing ribs are evenly arranged on the outer circumferential wall of the protective cover. Due to the complex structure of this product, the production cost is high. In addition, after the air spring is used for a long time, the roots of the reinforcing ribs are easily damaged. The resulting glass fiber debris and other residues scratch the undulating piston, affecting the life of the air spring shock absorber and also generating noise.

[0034] In the present invention Figure 1 The air spring structure with a flexible support piston shown in the figure includes an undulating piston 1 and a shock absorber 2. The upper part of the undulating piston 1 is provided with a buckling tooth segment 11, and the shock absorber 2 is provided with a protective cover assembly. The protective cover assembly includes a protective cover 4. The protective cover 4 is a cylindrical structure. A flexible support sleeve 5 is provided on the outer circular surface of the protective cover 4. The flexible support sleeve 5 and the protective cover 4 are interference fit; an active gap is provided between the outer wall of the flexible support sleeve 5 and the inner wall of the buckling tooth segment 11; a ventilation structure 12 is opened axially in the side wall of the buckling tooth segment 11, and the ventilation structure 12 passes through the side wall of the buckling tooth segment 11.

[0035] In order to avoid obstruction of gas circulation when components expand due to heat, thereby affecting the shock absorption performance, the ventilation structure 12 is a ventilation hole evenly spaced along the circumference of the buckling tooth segment 11. The ventilation hole axially penetrates the side wall of the buckling tooth segment 11, so that the longitudinal axial ventilation hole in the undulating piston 1 can connect the upper and lower chambers to ensure air pressure balance.

[0036] like Figure 4 As shown, in order to ensure the stability of ventilation, the ventilation holes are provided in at least two groups, or may be four or more groups; the ventilation holes are symmetrically arranged along the central axis of the pressing tooth segment 11.

[0037] In order to ensure smooth operation of the vent hole, the diameter of the vent hole is 2-4 mm.

[0038] In order to prevent the friction between the flexible support sleeve 5 and the undulating piston 1 from being too large, the material of the flexible support sleeve 5 is self-lubricating rubber, and the thickness of the flexible support sleeve 5 is 1.5-3mm. The flexible support sleeve 5 can be made of PTFE polytetrafluoroethylene self-lubricating rubber, NBR nitrile rubber, HNBR hydrogenated nitrile rubber, FKM fluororubber, etc., or lubricating oil can be applied to the flexible support sleeve 5 to achieve the effect of reducing friction. The rubber material is required to have a high elastic modulus to ensure that it can effectively absorb and buffer vibration energy during shock absorption, have good recovery ability after deformation, and good wear resistance, so as to ensure the NVH requirements of the whole vehicle and extend the life of parts such as protective covers. At the same time, the rubber material can preferably adopt materials with sufficient oil resistance, wear resistance, extreme environment tolerance, anti-aging and anti-fatigue, non-toxic and other requirements. In terms of process, the flexible rubber support sleeve is required to meet the dimensional tolerance requirements, the surface is smooth and lubricated to reduce noise and wear, and the transition fillet is set to reduce stress concentration to ensure the service life of the rubber. It is suitable for common rubber processing technologies such as injection molding and molding to ensure production efficiency and product quality. It tries to ensure that the thermal expansion coefficients of the rubber support sleeve and the protective cover are similar to avoid different interference fits between the two at different temperatures, which will affect the reliability of the fit.

[0039] In order to ensure the interference fit tightening force between the flexible support sleeve 5 and the protective cover 4, ensure that the flexible support sleeve 5 can be firmly attached to the protective cover 4 to meet the impact load and prevent the flexible support sleeve 5 from falling off when the air spring shock absorber is working, the interference fit between the flexible support sleeve 5 and the protective cover 4 is 0.1-0.3mm.

[0040] Taking into account the problem of thermal expansion and contraction, as well as the processing and assembly errors of the flexible support sleeve 5, in order to ensure that the protective cover assembly will not be obstructed in the undulating piston 1, the single-sided clearance between the outer wall of the flexible support sleeve 5 and the inner wall of the buckling tooth segment 11 is 1-2mm. The gap left between the flexible support sleeve 5 and the undulating piston 1 can ensure that the flexible support sleeve 5 will not frequently rub against the undulating piston 1 when the components move relative to each other in the vertical direction, which can ensure the life of the components while reducing abnormal noise. When encountering radial impact loads or alternating loads, the flexible support sleeve 5 should absorb the impact and vibration as much as possible, so that the peak load or fatigue load on the protective cover 4 itself is minimized, and the generation and expansion of cracks in stress concentration areas are avoided as much as possible.

[0041] In order to facilitate the assembly of the protective cover assembly, a chamfered structure 13 is provided on the inner side wall of the pressing tooth segment 11 for facilitating assembly.

[0042] In order to facilitate the assembly of the flexible support sleeve 5 on the protective cover 4, the height of the flexible support sleeve 5 is smaller than the height of the protective cover 4. In order to ensure that the outer wall of the protective cover assembly and the inner wall of the buckling tooth segment 11 can be supported by flexible buffering on the contact surface, the bottom of the flexible support sleeve 5 is flush with the bottom of the protective cover 4.

[0043] In order to achieve a lightweight design while ensuring that the parts have sufficient rigidity, the material of the protective cover 4 is PA66+GF50 plastic, and the material of the undulating piston 1 is 6082 aluminum alloy.

[0044] In the description of the present invention, it should be understood that terms such as "center", "longitudinal", "lateral", "vertical", "horizontal", "up", "down", "front", "back", "left", "right", "bottom", "inside", "outside", "top", "one end", "one side", "two ends", "both sides" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be understood as limiting the present invention.

[0045] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features being referred to. Thus, a feature defined as "first," "second," etc. may explicitly or implicitly include one or more of the features. In the description of this invention patent, unless otherwise specified, "plurality" means two or more.

[0046] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0047] The present invention is described above by way of example in conjunction with the accompanying drawings. It is obvious that the specific implementation of the present invention is not limited to the above-mentioned method. As long as various improvements are made using the method concept and technical solution of the present invention, or they are directly applied to other occasions, they all fall within the scope of protection of the present invention.

Claims

1. An air spring structure with a flexible support piston, comprising an undulating piston (1) and a shock absorber (2), wherein the upper portion of the undulating piston (1) is provided with a pressing tooth segment (11), and the shock absorber (2) is provided with a protective cover assembly, characterized in that: The protective cover assembly comprises a protective cover (4), the protective cover (4) is a cylindrical structure, a flexible support sleeve (5) is sleeved on the outer circumferential surface of the protective cover (4), and the flexible support sleeve (5) and the protective cover (4) are interference fit; a movable gap is provided between the outer side wall of the flexible support sleeve (5) and the inner side wall of the buckling tooth segment (11); a ventilation structure (12) is opened in the side wall of the buckling tooth segment (11) along the axial direction, and the ventilation structure (12) passes through the side wall of the buckling tooth segment (11).

2. The air spring structure with a flexible support piston according to claim 1, characterized in that: The ventilation structure (12) is ventilation holes evenly spaced along the circumference of the pressing tooth segment (11), and the ventilation holes penetrate the side wall of the pressing tooth segment (11) in the axial direction.

3. The air spring structure with a flexible support piston according to claim 2, characterized in that: At least two groups of vent holes are provided; the vent holes are symmetrically arranged along the central axis of the pressing tooth segment (11).

4. The air spring structure with a flexible support piston according to claim 2 or 3, characterized in that: The diameter of the vent hole is 2-4 mm.

5. The air spring structure with a flexible support piston according to claim 1, characterized in that: The material of the flexible support sleeve (5) is self-lubricating rubber, and the thickness of the flexible support sleeve (5) is 1.5-3 mm.

6. The air spring structure with a flexible support piston according to claim 1, characterized in that: The interference between the flexible support sleeve (5) and the protective cover (4) is 0.1-0.3 mm.

7. The air spring structure with a flexible support piston according to claim 1, characterized in that: The single-side gap between the outer side wall of the flexible support sleeve (5) and the inner side wall of the pressing tooth segment (11) is 1-2 mm.

8. The air spring structure with a flexible support piston according to claim 1, characterized in that: The inner side wall of the pressing tooth segment (11) is provided with a chamfered structure (13) for facilitating assembly.

9. The air spring structure with a flexible support piston according to claim 1, characterized in that: The height of the flexible support sleeve (5) is smaller than the height of the protective cover (4), and the bottom of the flexible support sleeve (5) is flush with the bottom of the protective cover (4).

10. The air spring structure with a flexible support piston according to claim 1, characterized in that: The material of the protective cover (4) is PA66+GF50 plastic, and the material of the undulating piston (1) is 6082 aluminum alloy.

Images