A shock absorber oil seal guide assembly with multi-stage sealing

Abstract

A multi-stage sealing shock absorber oil seal guide assembly includes a guide, a guide hole at the center of the guide, and a piston rod matching the guide hole. The guide is fitted with an annular oil seal seat. An annular limiting portion extends inward from the inner wall of the upper end port of the oil seal seat, through which the piston rod passes. Between the guide and the limiting portion, along the upward movement direction of the piston rod, a step seal, a first oil seal, and a second oil seal are sequentially arranged. An annular limiting step is provided on the inner wall of the middle portion of the oil seal seat. An annular guide cover plate is provided between the limiting step and the upper end face of the guide. An annular sealing groove is provided at the upper opening of the guide hole. This multi-stage sealing shock absorber oil seal guide assembly can form multiple seals, preventing oil leakage and the intrusion of external impurities even if one seal fails.

Description

Technical Field

[0001] This utility model relates to the field of automotive shock absorbers, and in particular to a shock absorber oil seal guide assembly with multi-stage sealing. Background Technology

[0002] In automotive shock absorbers, the oil seal guide assembly is a core component ensuring its sealing performance and motion accuracy. This assembly is installed at the inlet of the shock absorber's inner cylinder and consists of two key parts: a guide and an oil seal. The guide provides radial support and linear motion guidance for the piston rod, preventing piston rod wobbling or friction against the inner cylinder wall. The oil seal, through an interference fit between its elastic sealing lip and the piston rod, dynamically seals the high-pressure oil in the inner cylinder, preventing leakage.

[0003] However, the oil pressure inside the cylinder can seep through the micro-gap between the piston rod and the guide inner hole to the back of the oil seal, causing the oil seal to be subjected to unidirectional high-pressure impact for a long time. This eventually leads to irreversible plastic deformation of the oil seal under high pressure, and the interference force between the sealing lip and the piston rod is reduced. At the same time, the oil pressure will increase the contact stress between the lip and the piston rod, aggravating friction and wear, and eventually causing the seal to fail. The oil seal guide assembly of traditional shock absorbers uses a single oil seal design. Once the oil seal fails, it will not only cause oil leakage, resulting in a decrease in damping force and a deterioration in vehicle handling and comfort, but also allow external impurities to enter along the leakage path, wear the piston rod and guide, and cause abnormal noise or even jamming. Summary of the Invention

[0004] The present invention aims to solve the existing technical problem by providing a shock absorber oil seal guide assembly with multi-stage sealing, which can form multiple seals and prevent oil leakage and intrusion of external impurities even if one of the seals fails.

[0005] The technical solution adopted by this utility model to solve the above-mentioned technical problems is as follows:

[0006] This utility model discloses a shock absorber oil seal guide assembly with multi-stage sealing, including a guide, a guide hole located at the center of the guide, and a piston rod matching the guide hole. The guide is fitted with an annular oil seal seat. An annular limiting part extends inward from the inner wall of the upper end port of the oil seal seat, and the piston rod passes through the limiting part. A step seal, a first oil seal, and a second oil seal are sequentially arranged between the guide and the limiting part along the upward movement direction of the piston rod. An annular limiting step is provided on the inner wall of the middle part of the oil seal seat. An annular guide cover plate is provided between the limiting step and the upper end face of the guide. An annular sealing groove is provided at the upper end of the guide hole. The step seal is located in the sealing groove. An annular positioning part extends from the inner edge of the guide cover plate towards the step seal, and the positioning part presses the step seal against the lower side wall of the sealing groove.

[0007] The step seal consists of a main sealing ring fitted around the piston rod and an O-ring fitted around the main sealing ring; the outer circumferential surface of the O-ring is in contact with the inner circumferential surface of the sealing groove; and the inner wall of the main sealing ring is in contact with the outer wall of the piston rod.

[0008] The inner wall of the lower end of the main sealing ring is provided with an annular auxiliary groove; the outer wall of the upper end of the main sealing ring is provided with an annular auxiliary notch; the upper surface of the main sealing ring and the upper surface of the O-ring are both in contact with the lower surface of the positioning part; the lower surface of the positioning part is provided with an annular protrusion, and the lower end of the annular protrusion presses against the inner wall of the lower side of the auxiliary notch.

[0009] The lower inner wall of the guide hole is provided with an annular oil blocking groove; a bushing is provided inside the oil blocking groove and is fitted outside the piston rod.

[0010] The inner edge of the first oil seal is folded downward to form a first sealing lip outside the piston rod; the inner edge of the second oil seal is folded upward to form a second sealing lip outside the piston rod; the first oil seal is located between the lower surface of the second oil seal and the upper surface of the guide cover plate.

[0011] The guide is provided with an annular groove on the upper outer wall inside the oil seal seat and on the lower outer wall through which it extends into the oil seal seat. A matching sealing ring is provided in the annular groove. The guide is provided with an annular positioning step on the middle outer wall.

[0012] The beneficial effects of this utility model are:

[0013] Compared with existing technologies, the first seal formed by the multi-stage sealing shock absorber oil seal guide assembly of this utility model not only ensures the sealing effect but also intercepts most of the oil pressure. This allows the first oil seal (as the second seal) and the second oil seal (as the third seal) to operate in a low-pressure environment. The first and second oil seals only need to handle minor oil leakage, minimizing the sealing difficulty. At the same time, the presence of the second oil seal prevents external impurities from entering, providing a dustproof effect. The presence of three seals can minimize oil leakage. Even if one seal fails, the other two seals can still prevent leakage. The collaborative design of the first-stage pressure-bearing seal of the step seal and the redundant seal of the double oil seals effectively solves the failure problem of traditional single oil seals caused by high-pressure penetration. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of the shock absorber oil seal guide assembly with multi-stage sealing of this utility model;

[0015] Figure 2 yes Figure 1 An enlarged view of part A;

[0016] Figure 3This is a schematic diagram of the structure of a shock absorber using the multi-stage sealing shock absorber oil seal guide assembly of this utility model. Detailed Implementation

[0017] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0018] Please see Figures 1 to 3 This utility model provides a shock absorber oil seal guide assembly with multi-stage sealing, including a guide 1, a guide hole 2 located at the center of the guide 1, and a piston rod 3 matching the guide hole 2. The guide 1 is fitted with an annular oil seal seat 4. An annular limiting part 5 extends inward from the inner wall of the upper end port of the oil seal seat 4, and the piston rod 3 passes through the limiting part 5. A step seal 6, a first oil seal 7, and a second oil seal 8 are sequentially arranged between the guide 1 and the limiting part 5 along the upward movement direction of the piston rod 3. An annular limiting step 9 is provided on the inner wall of the middle part of the oil seal seat 4. An annular guide cover plate 10 is provided between the limiting step 9 and the upper end face of the guide 1. An annular sealing groove 11 is provided at the upper end opening of the guide hole 2. The step seal 6 is located in the sealing groove 11. An annular positioning part 12 extends from the inner edge of the guide cover plate 10 toward the step seal 6, and the positioning part 12 presses the step seal 6 onto the lower side wall of the sealing groove 11.

[0019] The step seal 6 consists of a main sealing ring 601 fitted around the piston rod 3 and an O-ring 602 fitted around the main sealing ring 601; the outer circumferential surface of the O-ring 602 is in contact with the inner circumferential surface of the sealing groove 11; the inner wall of the main sealing ring 601 is in contact with the outer wall of the piston rod 3.

[0020] The inner wall of the lower end of the main sealing ring 601 is provided with an annular auxiliary groove 13; the outer wall of the upper end of the main sealing ring 601 is provided with an annular auxiliary notch 14; the upper surface of the main sealing ring 601 and the upper surface of the O-ring 602 are both in contact with the lower surface of the positioning part 12; the lower surface of the positioning part 12 is provided with an annular protrusion 15, and the lower end of the annular protrusion 15 presses against the lower inner wall of the auxiliary notch 14.

[0021] The lower inner wall of the guide hole 2 is provided with an annular oil blocking groove 16; a bushing 17 is provided inside the oil blocking groove 16 and is fitted outside the piston rod 3.

[0022] The inner edge of the first oil seal 7 is folded downward to form a first sealing lip 18 outside the piston rod 3; the inner edge of the second oil seal 8 is folded upward to form a second sealing lip 19 outside the piston rod 3; the first oil seal 7 is located between the lower surface of the second oil seal 8 and the upper surface of the guide cover plate 10.

[0023] The guide 1 is provided with an annular groove 20 on the upper outer wall inside the oil seal seat 4 and on the lower outer wall through which the guide 1 extends to the oil seal seat 4. A matching sealing ring 21 is provided in the annular groove 20. The guide 1 is provided with an annular positioning step 22 on the middle outer wall.

[0024] The method of using this utility model is as follows:

[0025] The upper end of the inner cylinder 23 can be directly fitted onto the guide 1 and pressed against the positioning step 22. At this time, the sealing ring 21 on the lower end of the guide 1 can ensure the sealing between the inner wall of the inner cylinder 23 and the outer wall of the guide 1, while the sealing ring 21 on the upper end of the guide 1 can ensure the sealing between the outer wall of the guide 1 and the inner wall of the oil seal seat 4. The oil seal seat 4 can be fixed to the upper end port of the inner cylinder 23 by seam welding. The inner cylinder outer shell 24 is fitted onto the inner cylinder 23, while the outer cylinder 25 of the shock absorber is fitted onto the inner cylinder outer shell 24.

[0026] When the piston rod 3 of the shock absorber moves upward with the piston 301, the oil in the inner cylinder 23 is squeezed into the gap between the outer wall of the piston rod 3 and the inner wall of the guide hole 2. Finally, the oil pressure acts on the main sealing ring 601 of the step seal 6 and pushes upward to the upper groove of the auxiliary groove 13. At this time, the inner wall of the main sealing ring 601 is further pressed against the outer wall of the piston rod 3 under pressure, further enhancing the sealing effect. The presence of the O-ring 602 can elastically compensate for the wear of the main sealing ring 601, and at the same time ensure the sealing of the outer ring of the main sealing ring 601, preventing oil from leaking upward through the outer ring of the main sealing ring 601.

[0027] The first seal formed by Step Seal 6 not only ensures the sealing effect but also intercepts most of the oil pressure, allowing the first oil seal 7 (as the second seal) and the second oil seal 8 (as the third seal) to operate in a low-pressure environment. The first oil seal 7 and the second oil seal 8 only need to handle minor oil leakage, minimizing the sealing difficulty. At the same time, the presence of the second oil seal 8 can prevent the intrusion of external impurities, providing a dustproof effect. The presence of three seals can minimize the occurrence of oil leakage. Even if one seal fails, the other two seals can still provide a leak-proof effect. Through the synergistic design of the Step Seal 6's primary pressure-bearing seal and the redundant seals of the double oil seals, the failure problem caused by high-pressure penetration of traditional single oil seals is effectively solved.

[0028] The upper surfaces of the main sealing ring 601 and the O-ring 602 are both in contact with the lower surface of the positioning part 12, thereby ensuring that the guide cover plate 10 can press the step seal 6 composed of the main sealing ring 601 and the O-ring 602 tightly into the sealing groove 11, further ensuring the pressure bearing effect and sealing effect of the step seal 6. The lower end of the annular protrusion 15 on the lower surface of the positioning part 12 presses against the lower inner wall of the auxiliary notch 14. The presence of the annular protrusion 15 can limit the deformation of the main sealing ring 601 when the inner wall of the main sealing ring 601 is pressed further against the outer wall of the piston rod 3, further ensuring the sealing effect of the main sealing ring 601.

[0029] The lower inner wall of the guide hole 2 is provided with an annular oil blocking groove 16. Inside the oil blocking groove 16 is a bushing 17 that is attached to the piston rod 3. The bushing 17 can not only guide the piston rod 3 when it moves, but also intercept most of the oil when the oil leaks toward the step seal, thereby reducing the actual oil pressure borne by the step seal 6.

[0030] The inner edge of the first oil seal 7 is folded downward to form a first sealing lip 18 outside the piston rod 3. When oil leaks upward, the oil will accumulate on the outer ring of the first sealing lip 18. At this time, the oil pressure will further press the inner wall of the first sealing lip 18 tightly against the outer wall of the piston rod 3, further enhancing the sealing effect of the first oil seal 7. The second oil seal 8 can further seal above the first oil seal 7, while the presence of the second sealing lip 19 can intercept external impurities and prevent the intrusion of external impurities.

Claims

1. A shock absorber oil seal guide assembly having a multi-stage seal comprising a guide, a guide hole disposed in the center of the guide, and a piston rod matching the guide hole, characterized in that: The guide is fitted with an annular oil seal seat; an annular limiting part extends inward from the inner wall of the upper end port of the oil seal seat, through which the piston rod passes; between the guide and the limiting part, a step seal, a first oil seal, and a second oil seal are sequentially arranged along the upward movement direction of the piston rod; an annular limiting step is provided on the inner wall of the middle part of the oil seal seat; an annular guide cover plate is provided between the limiting step and the upper end face of the guide; an annular sealing groove is provided at the upper end opening of the guide hole; the step seal is located in the sealing groove; an annular positioning part extends from the inner edge of the guide cover plate toward the step seal, and the positioning part presses the step seal against the lower side wall of the sealing groove.

2. The shock absorber oil seal guide assembly with multi-stage sealing according to claim 1, characterized in that: The step seal consists of a main sealing ring fitted around the piston rod and an O-ring fitted around the main sealing ring; the outer circumferential surface of the O-ring is in contact with the inner circumferential surface of the sealing groove; and the inner wall of the main sealing ring is in contact with the outer wall of the piston rod.

3. A shock absorber oil seal guide assembly having multiple levels of sealing as defined in Claim 2, wherein: The inner wall of the lower end of the main sealing ring is provided with an annular auxiliary groove; the outer wall of the upper end of the main sealing ring is provided with an annular auxiliary notch; the upper surface of the main sealing ring and the upper surface of the O-ring are both in contact with the lower surface of the positioning part; the lower surface of the positioning part is provided with an annular protrusion, and the lower end of the annular protrusion presses against the inner wall of the lower side of the auxiliary notch.

4. A shock absorber oil seal guide assembly having multiple levels of sealing as defined in Claim 1, wherein: The lower inner wall of the guide hole is provided with an annular oil blocking groove; a bushing is provided inside the oil blocking groove and is fitted outside the piston rod.

5. A shock absorber oil seal guide assembly having multiple levels of sealing as defined in claim 1, wherein: The inner edge of the first oil seal is folded downward to form a first sealing lip outside the piston rod; the inner edge of the second oil seal is folded upward to form a second sealing lip outside the piston rod; the first oil seal is located between the lower surface of the second oil seal and the upper surface of the guide cover plate.

6. A shock absorber oil seal guide assembly having multiple levels of sealing as defined in claim 1, wherein: The guide is provided with an annular groove on the upper outer wall inside the oil seal seat and on the lower outer wall through which it extends into the oil seal seat. A matching sealing ring is provided in the annular groove. The guide is provided with an annular positioning step on the middle outer wall.

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