Air spring sliding column assembly

Abstract

The utility model relates to an air spring sliding column assembly which comprises an air spring and an integrated shock absorber, the shock absorber comprises a shock absorber pipe and a piston rod, one end of the piston rod is connected with a top rubber assembly through an installation mechanism, the top rubber assembly is contained in an upper air chamber upper piece and comprises a bearing piece, top rubber and an outer framework, one end of the top rubber is connected with the bearing piece, and the other end of the top rubber is connected with the outer framework. The end, facing the upper top cover, of the outer framework is provided with a flange part which is turned outwards in the radial direction, the upper top cover is detachably connected to the upper air chamber upper piece, the lower end face of the flange part abuts against the upper air chamber upper piece, a gap is formed between the lower end of the outer framework and the bottom space of the upper air chamber upper piece, and the lower end of the outer framework is in a suspended state. Therefore, the flange part of the flanging is tightly pressed with the upper part of the upper air chamber, and the outer framework is prevented from being in contact with the plastic air chamber to damage the plastic part.

Description

Technical Field

[0001] The utility model relates to the field of air springs, in particular to an air spring sliding column assembly. Background Art

[0002] The air spring strut assembly is used to buffer and attenuate the chassis of a motor vehicle relative to the motor vehicle body. The air spring strut assembly usually includes an air spring and an integrated shock absorber. The air spring is basically composed of an air spring cover, an air spring piston and an air spring airbag clamped between them. The shock absorber arranged in the air spring is connected to the wheel bracket on the one hand, and is fixed or installed in the air spring cover by using a shock absorber support through its piston rod on the other hand. The air spring cover is connected to the vehicle body, so the shock absorber force acts on the vehicle body through the air spring cover. In traditional designs, the air spring cover is mostly made of metal materials because metal is strong and durable and can withstand greater forces. However, the disadvantages of metal parts are that the processing is cumbersome and the cost is high, especially parts with complex shapes require multiple processes to complete. In order to reduce weight, plastics are now also used to make air spring covers, but plastic materials bring new problems: for example, the seal between plastic parts is difficult to install, the mold design is complicated, and the connection between plastic and shock absorber bracket is not stable enough, which is easy to loosen and leak, affecting the service life.

[0003] To solve the above problems, the existing Chinese invention patent with announcement number CN113374819B discloses an air spring strut assembly for a motor vehicle, the air spring strut assembly includes an integrated shock absorber and an air spring, the air spring includes an air spring cover and a rolling piston, a rolling airbag made of an elastomeric material is pressure-tightly fixed between the air spring cover and the rolling piston, thereby defining a volume elastic pressure chamber filled with compressed air, the rolling airbag rolls on the rolling piston while forming folds, the shock absorber includes a shock absorber tube and a piston rod that can be immersed in the shock absorber tube, the piston rod is connected to a shock absorber support member received in a support member receiving portion of the air spring cover, the shock absorber support member includes a bearing member, an elastomeric body and a sleeve, a closing member is installed in the support member receiving portion above the shock absorber support member, and the elastic member is arranged between the sleeve and the closing member.

[0004] However, the above-mentioned air spring strut assembly has the following defects in actual use:

[0005] 1. The interference fit between the top rubber (elastic body 25) and the air chamber (support receiving portion 21) requires continuous compression of the top rubber, which can easily lead to wear of the top rubber and reduce sealing and durability in long-term use.

[0006] 2. When the air chamber is made of plastic, the interference fit between the exoskeleton and the air chamber is prone to loosening and failure after a long time due to the low friction coefficient between plastics and insufficient clamping force.

[0007] 3. The prior art requires precision machining of the mating surfaces of the sleeve flange portion (27) and the sealing component (22), and relies on the precise compression amount of the elastic component (33) (such as a rubber ring or a disc spring), resulting in complex processes and increased costs.

[0008] 4. The sleeve (26) and the side wall of the air chamber are sealed only by a single seal (29). Under high pressure conditions, the seal may fail due to micro-movement of the sleeve. Summary of the invention

[0009] The technical problem to be solved by the utility model is to provide an air spring sliding column assembly in view of the deficiencies of the above-mentioned prior art.

[0010] To achieve the above object, the utility model provides the following technical solution: an air spring sliding column assembly, comprising an air spring and an integrated shock absorber. The air spring comprises an upper air chamber upper piece, an upper air chamber lower piece, an unwinding piston and an airbag, the airbag of the air spring is made of an elastomeric material and is fixed between the upper air chamber upper piece, the upper air chamber lower piece and the unwinding piston in a pressure-tight manner to form a volume elastic pressure chamber filled with compressed air. The shock absorber includes a shock absorber tube and a piston rod movably inserted into the shock absorber tube, one end of the piston rod is connected to a top rubber assembly through a mounting mechanism, the top rubber assembly is accommodated in an upper air chamber upper part, the top rubber assembly includes a bearing part, a top rubber and an exoskeleton, one end of the top rubber is engaged with the bearing part, and the other end is engaged with the exoskeleton, an upper top cover is provided above the top rubber assembly, and a radially outward-turned flange portion is provided at one end of the exoskeleton facing the upper top cover, the upper top cover is detachably connected to the upper air chamber upper part, the lower end surface of the flange portion is abutted against the upper air chamber upper part, and a gap is formed between the lower end of the exoskeleton and the bottom space of the upper air chamber upper part.

[0011] By adopting the above technical scheme, the air spring sliding column assembly directly presses the upper end face of the radially outward flange of the exoskeleton through the removable upper cover, replacing the continuous compression of the top rubber by the traditional interference fit, so that the top rubber only acts as an elastic buffer medium to bear dynamic loads rather than long-term static compression, thereby eliminating rubber fatigue wear. The design of the upper cover pressing the flange of the exoskeleton avoids the continuous compression of the top rubber by the traditional interference fit, and significantly extends the service life of the top rubber. The lower end face of the flange of the exoskeleton is against the upper air chamber upper part to form a stable axial force transmission path, ensuring that the clamping force is transmitted to the air chamber structure through the rigid contact surface, avoiding direct action on the top rubber. The gap design reserved between the lower end of the exoskeleton and the bottom of the upper air chamber upper part blocks the direct contact friction between the plastic air chamber and the exoskeleton, prevents wear and cracking of plastic parts due to vibration or thermal expansion, and at the same time provides a buffer space for micro-displacement under dynamic load, solves the problem of insufficient clamping force caused by the low friction coefficient of plastic material, and improves durability.

[0012] The above-mentioned air spring sliding column assembly can be further configured as follows: the upper air chamber upper part includes an upper air chamber insert made of metal material and embedded in the upper air chamber upper part, and an upper air chamber plastic air chamber made of plastic and fixedly connected to the upper air chamber insert, the upper air chamber plastic air chamber covers the upper air chamber insert at the bottom and is arranged against the outer peripheral surface of the exoskeleton, one end of the upper air chamber insert passes through the upper air chamber plastic air chamber and is detachably connected to the upper top cover, and the lower end surface of the flange part is arranged against the upper air chamber insert.

[0013] By adopting the above technical scheme, the upper air chamber upper part achieves a balance between lightness and strength through an upper air chamber insert made of metal material and an upper air chamber plastic air chamber composite structure made of plastic, wherein the metal insert is embedded in the interior of the plastic air chamber and is detachably connected to the upper top cover at the passing end, forming a stable force transmission path (the end of the metal insert passing through the plastic air chamber provides a high-strength threaded or snap-on connection interface), directly bearing the clamping force of the upper top cover, and avoiding deformation or cracking of the plastic air chamber due to insufficient rigidity; the plastic air chamber is coated with the metal insert at the bottom, and an integrated structure is formed by injection molding or mechanical fixation, which not only isolates the metal insert from the exoskeleton At the same time, the outer peripheral surface of the exoskeleton is abutted against the plastic air chamber to form a physical partition layer to block the interference of external vibration on the internal airtight structure. The design of the lower end surface of the flange and the metal insert abuts against each other, and the axial load of the exoskeleton is transmitted to the air chamber body through the rigid metal insert, which avoids the plastic air chamber from bearing concentrated stress and solves the loosening problem of the traditional all-plastic air chamber due to insufficient clamping force. The composite structure takes into account the processing cost, structural strength and durability through the synergistic effect of metal and plastic, and systematically realizes the unity of lightweight and high reliability.

[0014] The above-mentioned air spring sliding column assembly can be further configured as follows: the upper air chamber insert is provided with a limit bearing portion toward the bottom of the top glue assembly, the upper air chamber plastic chamber is covered with a plastic limit portion at the position corresponding to the limit bearing portion, the plastic limit portion cooperates with the upper top cover to form a floating cavity for the top glue assembly to be axially lifted and lowered therein, a suspension portion is provided at one end of the outer skeleton away from the flange portion, and there is the gap in the space between the suspension portion and the plastic limit portion.

[0015] By adopting the above technical solution, a limit bearing part is provided on the upper air chamber insert toward the bottom of the top glue assembly, and a plastic limit bearing part is covered on the upper air chamber plastic chamber corresponding to the limit bearing part. The two cooperate to form a floating cavity for axial lifting and lowering of the top glue assembly. The dynamic load transmitted by the shock absorber is absorbed through the elastic deformation of the top glue assembly to avoid cracking of the plastic air chamber due to rigid impact. This design reduces the risk of stress concentration in plastic parts and improves durability through dual paths of floating buffering and gap isolation, while preventing damage to plastic parts.

[0016] The above-mentioned air spring sliding column assembly can be further configured as follows: a plastic partition portion is provided at the outer peripheral surface of the outer frame corresponding to the plastic air chamber of the upper air chamber, one end of the plastic partition portion is abutted against the outer frame, and the other end is fixedly connected to the upper air chamber insert through an annular clamping portion, and one end of the flange portion of the outer frame extends out of the plastic partition portion and is abutted and fixed against the upper air chamber insert.

[0017] By adopting the above technical solution, a plastic baffle is provided at the outer peripheral surface of the plastic air chamber of the upper air chamber corresponding to the exoskeleton. One end of the baffle is abutted against the exoskeleton to form a physical sealing barrier, and the other end is fixed to the upper air chamber insert through an annular clamping part to block the external vibration from being transmitted to the airtight cavity. The flange part of the exoskeleton extends out of the baffle and abuts against the insert to ensure that the clamping force is directly transmitted by the metal insert to avoid the plastic air chamber from being subjected to concentrated loads. This design solves the problems of plastic air chamber sealing failure and insufficient clamping force by separating the baffle seal from the rigid force transmission path.

[0018] The above-mentioned air spring strut assembly can be further configured as follows: a first sealing groove is provided at one end of the outer frame corresponding to the plastic baffle portion, and a first sealing ring is provided in the first sealing groove to abut against the plastic baffle portion.

[0019] By adopting the above technical solution, a first sealing groove is provided at one end of the exoskeleton corresponding to the plastic baffle part, and a first sealing ring is arranged in the groove to abut against the baffle part. The elastic compression of the sealing ring fills the microscopic gap on the mating surface to prevent leakage of high-pressure gas along the interface between the exoskeleton and the plastic air chamber. The standardized sealing groove design ensures the positioning accuracy of the sealing ring and avoids sealing failure caused by assembly deviation.

[0020] The above-mentioned air spring strut assembly can be further configured as follows: the top glue is fixed to the outer frame by vulcanization, and the top glue is fixed to the bearing component by vulcanization.

[0021] By adopting the above technical solution, the top glue is joined to the outer frame and the load-bearing parts through a vulcanization process. The vulcanization interface forms a continuous transition layer combined by chemical bonds, eliminating the risk of interface peeling of traditional adhesives. The elastomer molecular chain of the top glue and the metal / plastic matrix form a stable connection through cross-linking reaction, evenly dispersing the dynamic load. This vulcanization bonding design solves the problems of sealing failure and shortened life caused by debonding of traditional top glue.

[0022] The above-mentioned air spring strut assembly can be further configured such that the distance of the gap is 1-5 mm.

[0023] Using the above technical solution, the distance of the gap is limited to 1-5 mm, which is calculated based on the difference in thermal expansion coefficients between plastic (preferably PA66-GF30) and metal (preferably aluminum alloy). This ensures that within the temperature range of -40°C to 120°C, the gap can accommodate the expansion and contraction of the material, avoiding thermal stress-induced structural deformation or sealing surface cracking, and preventing the gap from being too small to cause interference or too large to reduce structural rigidity.

[0024] The above-mentioned air spring strut assembly can be further configured as follows: the upper air chamber insert is provided with a first threaded portion at a position corresponding to the upper top cover, the upper top cover is threadedly connected to the upper air chamber insert, and cooperates with the upper air chamber insert to clamp the flange portion.

[0025] By adopting the above technical solution, the upper air chamber insert is provided with a first threaded portion, and the upper top cover cooperates with the insert through a threaded connection to ensure that the clamping force is controllable and evenly distributed. The threaded clamping replaces the traditional interference fit, eliminating the risk of plastic air chamber deformation caused by pressing force deviation, while reducing the processing accuracy requirements.

[0026] The above-mentioned air spring sliding column assembly can be further configured as follows: the mounting mechanism includes a load-bearing mounting portion arranged at one end of the piston rod corresponding to the load-bearing member, a second threaded portion and a nut threadedly connected to the second threaded portion, the load-bearing mounting portion and the connecting end of the piston rod form a load-bearing step portion, the load-bearing member is sleeved on the load-bearing mounting portion, one end of which is abutted against the load-bearing step portion, and the other end is locked on the load-bearing mounting portion by a nut.

[0027] By adopting the above technical solution, in order to meet the needs of installing an empty spring for a built-in valve / magnetorheological shock absorber, the upper end of the shock absorber piston rod needs to extend the wiring harness for damping control, so a special structure is required to seal the piston rod and the top rubber. The installation mechanism cooperates with the nut through the stepped structure of the load-bearing mounting part to disperse the axial load of the piston rod to the step surface of the bearing part, avoiding single-point stress concentration. The nut locks the bearing part through the second threaded part to achieve stable detachable assembly.

[0028] The above-mentioned air spring sliding column assembly can be further configured as follows: the surface of the bearing member corresponding to the bearing mounting portion is provided with a first step portion and a second step portion arranged in a continuous step shape, a clamping groove is formed between the first step portion and the bearing mounting portion, a second sealing groove is formed between the second step portion and the bearing mounting portion, a clamping cover is provided in the clamping groove, a second sealing ring is provided in the second sealing groove, one end of the clamping cover is arranged in the clamping groove and abuts against a nut, and the other end is inserted into the second sealing groove to apply the pre-tightening force of the nut to the bearing member.

[0029] By adopting the above technical solution, the nut locks the carrier through the second threaded portion. The stepped surface formed by the first step portion and the second step portion increases the contact area between the carrier and the piston rod, disperses the dynamic load, and reduces the risk of interface wear. The clamping cover transfers the pre-tightening force of the nut to the carrier through the clamping groove, avoids local stress concentration caused by single-point force, and ensures uniform pressure distribution at the connection interface between the carrier and the piston rod. The second sealing ring fills the second sealing groove to improve air tightness. Combined with the physical clamping effect of the clamping cover, a double sealing barrier is formed. The clamping cover is embedded in the clamping groove and extends to the second sealing groove to form an axial mechanical locking structure to prevent the nut from loosening under vibration load and improve connection reliability.

[0030] The utility model is further described below in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a cross-sectional schematic diagram of an embodiment of the utility model.

[0032] Figure 2 It is a cross-sectional schematic diagram of the air spring part of an embodiment of the utility model.

[0033] Figure 3 for Figure 2 Enlarged view of point A. DETAILED DESCRIPTION

[0034] like Figures 1 to 3 As shown, an air spring sliding column assembly includes an air spring 23 and an integrated shock absorber 20. The air spring 23 is composed of an upper air chamber upper part 25, an upper air chamber lower part 12, an unwinding piston 16 and an air bag 231 made of an elastomer. The air bag 231 is fixed between the upper air chamber upper part 25, the upper air chamber lower part 12 and the unwinding piston 16 in a pressure-tight manner to form a volume elastic pressure chamber filled with compressed air. The shock absorber 20 includes a shock absorber tube 19 and a piston rod 24 that can be movably inserted into the shock absorber tube 19. One end of the piston rod 24 is connected to the top rubber assembly through a mounting mechanism. The top rubber assembly is accommodated in the upper air chamber upper part 25, including a bearing part 10, a top rubber 3 and an exoskeleton 2. One end of the top rubber 3 is vulcanized and bonded to the bearing part 10, and the other end is vulcanized and bonded to the exoskeleton 2 to form a stable elastic interface. An upper top cover 4 is provided above the exoskeleton 2, and a radially outward-turned flange portion 21 is provided at one end thereof facing the upper top cover 4. The upper top cover 4 is detachably connected to the upper air chamber upper part 25 by threads, and abuts against the upper end surface of the flange portion 21, and the lower end surface of the flange portion 21 abuts against the upper air chamber upper part 25. A gap 22 of 1-5 mm is formed between the lower end of the exoskeleton 2 and the bottom of the upper air chamber upper part 25 to avoid direct contact and friction between the plastic air chamber and the exoskeleton.

[0035] like Figure 2As shown, the upper air chamber upper part 25 adopts a metal-plastic composite design, including an upper air chamber insert 5 made of metal material and an upper air chamber plastic air chamber 6 made of plastic material. The upper air chamber insert 5 is embedded in the plastic air chamber 6, and one end thereof passes through the plastic air chamber 6 and is threadedly connected to the upper top cover 4 to form a stable compression force transmission path. The plastic air chamber 6 covers the upper air chamber insert 5 at the bottom and abuts against the outer peripheral surface of the outer frame 2, and is fixed to the upper air chamber insert 5 through the annular clamping portion 621. The lower end surface of the flange portion 21 directly abuts against the upper air chamber insert 5 to ensure rigid force transmission and prevent the plastic air chamber 6 from being subjected to concentrated loads. The upper air chamber insert 5 is directed toward A limiting bearing portion 51 is provided on one side of the top rubber assembly, and the plastic air chamber 6 is correspondingly covered to form a plastic limiting portion 61. The two cooperate with the exoskeleton 2 to form a floating cavity 41 for axial micro-movement of the top rubber assembly to absorb the dynamic impact of the shock absorber. A suspension portion 26 is provided at one end of the exoskeleton 2 away from the flange portion 21, and a gap 22 is reserved between the plastic limiting portion 61 to further isolate vibration transmission. A first sealing groove is provided at one end of the exoskeleton 2 corresponding to the plastic blocking portion 62, and a first sealing ring 8 is built in to block gas leakage along the interface between the exoskeleton 2 and the plastic air chamber 6. The bearing member 10 is connected to the piston rod 24 through a mounting mechanism.

[0036] like Figure 3 As shown, the bearing mounting portion 241 of the piston rod 24 is provided with a bearing step portion 243, and the bearing member 10 is sleeved on the mounting portion 241, with one end abutting the step portion 243 and the other end locked by the nut 7. The surface of the bearing member 10 is provided with a first step portion 101 and a second step portion 102 in a continuous step shape, which respectively form a clamping groove 91 and a second sealing groove 111 with the mounting portion 241, and a clamping cover 9 and a second sealing ring 11 are built in. One end of the clamping cover 9 abuts the nut 7, and the other end extends to the second sealing groove 111 to clamp the second sealing ring 11, so as to evenly transfer the nut preload force to the bearing member 10, thereby forming a progressive sealing barrier.

[0037] like Figure 1-Figure 3 As shown, the air spring strut assembly of the utility model is connected by threading the upper cover 4 to tighten the flange portion 21 of the outer frame 2, replacing the traditional interference fit and eliminating the long-term compression wear of the top glue 3. The composite structure of the metal insert 5 and the plastic air chamber 6 takes into account both strength and lightness. The gap 22 is designed to block plastic friction and accommodate thermal expansion. The floating cavity 41 is installed in coordination with the sealing ring and the clamping cover to improve the high-pressure sealing reliability and dynamic load adaptability. This solution systematically solves the problems of top glue wear, loosening of plastic parts and sealing failure, and significantly reduces processing and assembly costs.

Claims

1. An air spring sliding column assembly, comprising an air spring and an integrated shock absorber, the air spring comprising an upper air chamber upper piece, an upper air chamber lower piece, an unwinding piston and an air bag, the air bag of the air spring being made of an elastomeric material and being fixed between the upper air chamber upper piece, the upper air chamber lower piece and the unwinding piston in a pressure-tight manner to form a volume elastic pressure chamber filled with compressed air, the shock absorber comprising a shock absorber tube and a piston rod movably inserted into the shock absorber tube, one end of the piston rod being connected to a top glue assembly through a mounting mechanism, the top glue assembly being accommodated in the upper air chamber upper piece, the top glue assembly comprising a bearing member, a top glue and an outer frame, one end of the top glue being engaged with the bearing member, and the other end being engaged with the outer frame, an upper top cover being provided above the top glue assembly, and an end of the outer frame facing the upper top cover being provided with a radially outward-turned flange portion, characterized in that: The upper cover is detachably connected to the upper air chamber upper piece, the lower end surface of the flange portion abuts against the upper air chamber upper piece, and a gap exists between the lower end of the outer frame and the bottom space of the upper air chamber upper piece.

2. The air spring strut assembly according to claim 1, characterized in that: The upper air chamber upper part includes an upper air chamber insert made of metal material and embedded in the upper air chamber upper part, and an upper air chamber plastic air chamber made of plastic and fixedly connected to the upper air chamber insert. The upper air chamber plastic air chamber covers the upper air chamber insert at the bottom and is arranged against the outer peripheral surface of the exoskeleton. One end of the upper air chamber insert passes through the upper air chamber plastic air chamber and is detachably connected to the upper top cover. The lower end surface of the flange part is arranged against the upper air chamber insert.

3. The air spring strut assembly according to claim 2, characterized in that: The upper air chamber insert is provided with a limiting bearing part toward the bottom of the top glue assembly, and the upper air chamber plastic chamber is covered with a plastic limiting part at the corresponding limiting bearing part. The plastic limiting part cooperates with the upper top cover to form a floating cavity for the top glue assembly to rise and fall axially. A suspension part is provided at one end of the outer skeleton away from the flange part, and there is the gap in the space between the suspension part and the plastic limiting part.

4. The air spring strut assembly according to claim 3, characterized in that: A plastic baffle is provided at the outer peripheral surface of the outer frame corresponding to the upper air chamber plastic chamber. One end of the plastic baffle is against the outer frame, and the other end is fixedly connected to the upper air chamber insert through an annular clamping part. One end of the flange of the outer frame extends out of the plastic baffle and is fixed against the upper air chamber insert.

5. The air spring strut assembly according to claim 4, characterized in that: A first sealing groove is provided at one end of the outer frame corresponding to the plastic baffle portion, and a first sealing ring is provided in the first sealing groove to abut against the plastic baffle portion.

6. The air spring strut assembly according to claim 2, characterized in that: The top rubber is fixed to the outer frame by vulcanization, and the top rubber is fixed to the bearing component by vulcanization.

7. The air spring strut assembly according to claim 3, characterized in that: The distance of the gap is 1-5 mm.

8. An air spring strut assembly according to any one of claims 2 to 7, characterized in that: The upper air chamber insert is provided with a first threaded portion at a position corresponding to the upper top cover, and the upper top cover is threadedly connected to the upper air chamber insert and cooperates with the upper air chamber insert to clamp the flange portion.

9. An air spring strut assembly according to any one of claims 1 to 7, characterized in that: The mounting mechanism includes a load-bearing mounting portion arranged at one end of the piston rod corresponding to the load-bearing member, a second threaded portion and a nut threadedly connected to the second threaded portion. The load-bearing mounting portion and the connecting end of the piston rod form a load-bearing step portion. The load-bearing member is sleeved on the load-bearing mounting portion, one end of which is against the load-bearing step portion, and the other end is locked on the load-bearing mounting portion by the nut.

10. The air spring strut assembly according to claim 9, characterized in that: The surface of the bearing member corresponding to the bearing mounting portion is provided with a first step portion and a second step portion which are arranged in a continuous step shape, a clamping groove is formed between the first step portion and the bearing mounting portion, a second sealing groove is formed between the second step portion and the bearing mounting portion, a clamping cover is provided in the clamping groove, a second sealing ring is provided in the second sealing groove, one end of the clamping cover is arranged in the clamping groove and abuts against the nut, and the other end is inserted into the second sealing groove to apply the pre-tightening force of the nut to the bearing member.

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