A guide for a magneto-rheological shock absorber

Abstract

This utility model discloses a guide for a magnetorheological damper, including a guide housing with an inner end and an outer end. The guide housing contains a dustproof sealing assembly, an outer oil seal assembly, a bushing assembly, and an inner oil seal assembly. The bushing assembly includes a bushing mounting cavity and a lubricating fluid cavity that are interconnected. A bushing mounting seat is provided within the bushing mounting cavity, and a bushing is provided within the bushing mounting seat. The bushing and piston rod are slidably fitted. A pressure-reducing channel and a balance channel are provided circumferentially on the bushing mounting seat, and the pressure-reducing channel and the balance channel are interconnected through the bushing mounting cavity. This invention solves the problem that existing dampers experience thermal expansion and contraction during high-speed operation, resulting in internal air pressure expansion and pressure inconsistency between the upper and lower ends. Thermal expansion generates gas or bubbles, and some of this gas enters the guide through the lower guide oil seal and cannot escape, increasing the internal pressure of the guide and thus increasing friction, causing noise and vibration.

Description

Technical Field

[0001] This utility model relates to the field of magnetorheological damper technology, specifically a guide for a magnetorheological damper. Background Technology

[0002] Magnetorheological dampers contain magnetorheological fluid, which is greatly affected by temperature changes. When the temperature is high, the fluid expands and generates a large positive pressure inside, while when the temperature is low, the fluid contracts and generates a large negative pressure. Traditional guides seal the various cavities to maintain a sealing effect. However, the contact area between the bushing and the piston rod is the largest, resulting in the greatest frictional heating effect and thus a large expansion effect in this area. The cavities between two adjacent cavities are oil-sealed, and the expansion effect caused by frictional heating is small. Therefore, a pressure difference exists, and the frictional force at the upper and lower ends of the guide bushing is inconsistent, causing additional wear on one end. At the same time, the air bubbles caused by heating further increase the internal air pressure and increase the friction.

[0003] Chinese patent document CN202211172734.9 discloses a guide assembly including a guide and a guide bushing. The guide includes a through hole extending through it axially, and has a first end and a second end opposite to each other axially. The through hole includes a first hole and a second hole communicating with each other. The diameter of the first hole is smaller than the diameter of the second hole, and the second hole is located at the first end of the guide, with the first hole located on the side of the second hole closer to the second end. A first groove is provided on the sidewall of the second hole, and the guide bushing is located within the second hole and fits against the sidewall of the second hole outside the first groove, such that the first groove forms a channel connecting the exterior of the guide with the interior space of the guide.

[0004] The magnetorheological fluid in the reservoir of the shock absorber undergoes thermal expansion and contraction during high-speed movement, inevitably resulting in the presence of gas or air bubbles. Some of this gas enters the guide valve through the lower guide valve oil seal and cannot escape, increasing the internal pressure and friction, causing noise and vibration, and affecting the shock absorber's performance and stability. Low friction and high durability cannot be simultaneously achieved. Therefore, it is necessary to design a guide valve structure for a low-internal-pressure magnetorheological shock absorber to improve sealing and reduce the risk of oil and gas leakage. Utility Model Content

[0005] The purpose of this invention is to provide a guide for a magnetorheological damper, which aims to improve the existing damper's performance during high-speed operation. Due to thermal expansion and contraction, the internal air pressure expands with heat, and the air pressure at the upper and lower ends is inconsistent. Thermal expansion generates gas or bubbles, and some gas enters the guide through the lower guide's oil seal and cannot be discharged. This increases the internal pressure of the guide, thereby increasing friction and causing noise and vibration.

[0006] This utility model is implemented as follows: a guide for a magnetorheological damper includes a guide housing, the guide housing includes an inner end and an outer end, and a connecting hole is provided between the inner end and the outer end for placing a piston rod. In the direction from the outer end to the inner end, the aforementioned guide housing is provided with a dustproof sealing assembly, an outer oil seal assembly, a bushing assembly, and an inner oil seal assembly. The aforementioned bushing assembly includes a bushing mounting cavity and a lubricating fluid cavity that are interconnected. A bushing mounting seat is provided in the aforementioned bushing mounting cavity. The aforementioned lubricating fluid cavity is filled with lubricating oil. A bushing is provided in the aforementioned bushing mounting seat. The aforementioned bushing is in sliding fit with the piston rod. A pressure reducing channel and a balance channel are provided in the circumferential direction of the aforementioned bushing mounting seat. The aforementioned pressure reducing channel and the balance channel are interconnected through the aforementioned bushing mounting cavity. The guide housing described above is also provided with a limit snap ring and multiple outer sealing strips on its side wall.

[0007] As one embodiment of the present invention, the dustproof sealing assembly includes a dustproof sealing groove and a dustproof sealing ring. The dustproof sealing ring includes a conical isolation cover and an annular connecting part. The end of the annular connecting part is engaged with the side wall of the dustproof sealing groove.

[0008] As one embodiment of the present invention, the above-mentioned external oil seal assembly includes an external oil seal cavity and an external oil seal ring. The external oil seal cavity and the dustproof sealing groove are connected by a connecting hole. The external oil seal ring includes an annular snap-fit ​​part and a U-shaped sealing ring. One end of the U-shaped sealing ring abuts against the piston rod, and the other end of the U-shaped sealing ring abuts against the side wall of the external oil seal cavity.

[0009] In one embodiment of this utility model, the bushing mounting base is an annular structure, comprising an outer ring and an inner ring. The bushing is snapped onto the inner ring of the bushing mounting base. A balance cavity is formed between the lower surface of the outer oil seal assembly and the upper surface of the bushing mounting base. The pressure-reducing channel is disposed on the outer ring and communicates with the balance cavity. The upper and lower ends of the inner ring are also provided with flow-guiding chamfers. The balance channel is located between the bushing mounting base and the bushing.

[0010] As one embodiment of the present invention, the aforementioned voltage reduction channel includes a middle transverse channel and several lower connecting channels and upper connecting channels connected to the middle transverse channel. The aforementioned middle transverse channel is located in the middle of the aforementioned outer ring, and the aforementioned middle transverse channel is arranged around the aforementioned outer ring and connected end to end.

[0011] In one embodiment of this utility model, the number of the lower connecting channels and the upper connecting channels are equal and there are two or more of each. The lower connecting channels or the upper connecting channels are evenly arranged in the circumferential direction of the outer ring, and the lower connecting channels and the upper connecting channels are spaced apart.

[0012] In one embodiment of this utility model, the depth of each of the aforementioned lower connecting channels and upper connecting channels is greater than the depth of the aforementioned intermediate transverse channel.

[0013] As one embodiment of this utility model, the inner wall of the bushing mounting cavity is provided with a plurality of upper conical grooves and lower conical grooves spaced apart vertically. The lengths of the upper conical grooves and lower conical grooves are the same as the lengths of the upper connecting channel and the lower connecting channel, respectively, and their quantities correspond one-to-one.

[0014] As one embodiment of this utility model, the inner oil seal assembly includes an inner oil seal cavity and an inner oil seal mounting base. An inner oil seal ring is snapped onto the inner oil seal mounting base, and the inner oil seal ring is sleeved on the piston rod.

[0015] As one embodiment of this utility model, a guide buffer is provided on the inner end of the guide housing.

[0016] The beneficial effects of this utility model are: 1. The bushing mounting base of this utility model is provided with a pressure reduction channel and a balance channel, which expands the internal space of the guide and increases the fluidity of the internal space. During the operation of the shock absorber, the internal air pressure can be kept consistent quickly, and the pressure on the upper and lower contact surfaces of the shock absorber piston rod is the same, maintaining stable friction. This reduces the loss caused by friction imbalance and increases the service life of the guide. 2. The bushing mounting base of this utility model is provided with a pressure reducing channel, which can not only allow gas to flow and balance the gas pressure, but also absorb and release the internal stress of the guide bushing mounting base, thereby improving the fatigue life of the guide. 3. This utility model is equipped with a multi-layer sealing structure, including an outer sealing strip, a dustproof sealing component, an outer oil seal component, and an inner oil seal component, which improves the overall sealing effect and reduces the risk of oil and gas leakage. Attached Figure Description

[0017] The accompanying drawings, which form part of this utility model, are used to provide a further understanding of the utility model, making other features, objects, and characteristics of the utility model more apparent. The illustrative embodiments of the utility model and their descriptions are used to explain the utility model and do not constitute an undue limitation of the utility model.

[0018] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is an internal sectional view of the present invention; Figure 3 This is a cross-sectional schematic diagram of the guide housing of this utility model; Figure 4 This is a schematic diagram of the internal structure of this utility model; Figure 5 This is a schematic cross-sectional view of the overall structure of this utility model; Figure 6 yes Figure 5 Enlarged view of some of the structures in the image; Figure 7 This is a schematic diagram of the structure of the bushing mounting base of this utility model; Figure 8 This is a structural schematic diagram of Embodiment 2 of the present invention; Figure 9 This is a structural schematic diagram of Embodiment 3 of the present invention; In the figure: 1. Guide housing; 10. Connecting hole; 11. Inner end; 12. Outer end; 13. Piston rod; 14. Guide buffer; 15. Limiting snap ring; 16. Outer sealing strip; 2. Dustproof sealing assembly; 20. Dustproof sealing groove; 21. Dustproof sealing ring; 211. Conical isolation cover; 212. Annular connecting part; 3. Outer oil seal assembly; 30. Outer oil seal cavity; 31. Outer oil seal ring; 311. Annular snap-fit ​​part; 312. U-shaped sealing ring; 3. Balance chamber. 20; Bushing assembly 4; Bushing mounting cavity 40; Upper conical groove 401; Lower conical groove 402; Lubricating fluid cavity 41; Inner oil seal assembly 5; Inner oil seal cavity 50; Inner oil seal mounting seat 51; Inner oil seal ring 52; Bushing mounting seat 6; Outer ring 61; Pressure reducing channel 60; Intermediate transverse channel 601; Lower connecting channel 602; Upper connecting channel 603; Inner ring 62; Flow guide chamfer 621; Bushing 7; Balance channel 70. Detailed Implementation

[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0020] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0021] Example 1: As Figure 1-7As shown, this utility model provides a guide for a magnetorheological damper, which solves the problem that during the operation of the magnetorheological damper, frictional heating causes internal air pressure to expand due to heat, resulting in inconsistent air pressure at the upper and lower ends. At the same time, long-term high-speed operation generates air bubbles, which increases the pressure inside the guide, increases the friction between the bushing and the piston rod, increases wear, increases the overall wear of the guide, reduces its service life, and easily causes instability of the damper.

[0022] This invention mainly establishes an internal circulation channel in the guide to ensure consistent air pressure at both ends of the bushing, thereby guaranteeing consistent friction. At the same time, it increases the internal space to avoid friction-induced heating or bubble formation, which would increase friction and lead to increased wear.

[0023] like Figure 1-2 As shown, the guide of this magnetorheological damper mainly includes a guide housing 1, which includes an inner end 11 and an outer end 12. A connecting hole 10 is provided between the inner end 11 and the outer end 12 for placing the piston rod 13. In the direction from the outer end 12 to the inner end 11, a dustproof sealing assembly 2, an outer oil seal assembly 3, a bushing assembly 4, and an inner oil seal assembly 5 are provided inside the guide housing 1.

[0024] like Figure 2 As shown, the guide of the magnetorheological damper includes a guide housing 1, with a connecting hole 10 between its inner end 11 and outer end 12 for the piston rod 13 to pass through. Along the direction from the outer end 12 to the inner end 11, a dustproof sealing assembly 2 is used to prevent external dust from entering the interior of the guide, while an outer oil seal assembly 3 and an inner oil seal assembly 5 are used to prevent the internal magnetorheological fluid from flowing out.

[0025] like Figures 3-4 As shown, the dustproof sealing assembly 2 includes a dustproof sealing groove 20 and a dustproof sealing ring 21. The dustproof sealing ring 21 includes a conical isolation cover 211 and an annular connecting part 212. The end of the annular connecting part 212 is engaged with the side wall of the dustproof sealing groove 20. The conical isolation cover 211 is tilted outward to effectively block external dust from entering.

[0026] like Figures 4-5 As shown, the outer oil seal assembly 3 includes an outer oil seal cavity 30 and an outer oil seal ring 31. The outer oil seal cavity 30 and the dustproof sealing groove 20 are connected by a connecting hole 10. The outer oil seal ring 31 includes an annular snap-fit ​​part 311 and a U-shaped sealing ring 312. One end of the U-shaped sealing ring 312 abuts against the piston rod 13, and the other end of the U-shaped sealing ring 312 abuts against the side wall of the outer oil seal cavity 30, forming a highly efficient sealing effect and preventing leakage of internal lubricating oil.

[0027] The bushing assembly 4 includes a bushing mounting cavity 40 and a lubricating fluid cavity 41 that are interconnected. A bushing mounting seat 6 is provided in the bushing mounting cavity 40, and the lubricating fluid cavity 41 is filled with lubricating oil. A bushing 7 is provided in the bushing mounting seat 6. The bushing 7 is slidably fitted with the piston rod 13. A pressure reducing channel 60 is provided on the side wall of the bushing mounting seat 6. The pressure reducing channel 60 balances the pressure at both ends of the bushing 7, ensuring that the friction at both ends of the bushing 7 is consistent and that the lubrication is uniform, thus reducing wear.

[0028] Specifically, such as Figures 5-7 As shown, the bushing mounting base 6 has an annular structure, including an outer ring 61 and an inner ring 62. The bushing 7 is snapped into the inner ring 62 of the bushing mounting base 6. A balance cavity 320 is formed between the lower surface of the outer oil seal assembly 3 and the upper surface of the bushing mounting base 6. The pressure reduction channel 60 is disposed on the outer ring 61 and communicates with the balance cavity 320. The upper and lower ends of the inner ring 62 are also provided with flow guiding chamfers 621. The balance channel 70 is located between the bushing mounting base 6 and the bushing 7.

[0029] This invention mainly establishes an internal circulation channel to ensure consistent air pressure at both ends of the bushing, thereby guaranteeing consistent friction. At the same time, it increases the internal space to avoid friction-induced heating or bubble formation, which would increase friction and lead to increased wear.

[0030] like Figure 7 As shown, the step-down channel 60 includes a central transverse channel 601 and several lower connecting channels 602 and upper connecting channels 603 connected to the central transverse channel 601. The central transverse channel 601 is located in the middle of the outer ring 61 and is arranged around the outer ring 61 with its ends connected. The central transverse channel 601 is shaped like an annular groove to connect the lower connecting channels 602 and upper connecting channels 603. The lengths of both the lower connecting channels 602 and upper connecting channels 603 are greater than half the length of the outer ring 61.

[0031] To ensure smooth gas flow, the number of lower connecting channels 602 and upper connecting channels 603 is equal and there are more than two of each. Each lower connecting channel 602 or upper connecting channel 603 is evenly arranged in the circumferential direction of the outer ring 61, and each lower connecting channel 602 and upper connecting channel 603 is spaced apart.

[0032] In this embodiment, there are three lower connection channels 602 and three upper connection channels 603. The lower connection channels 602 are spaced 120 degrees apart, and the lower connection channels 602 and the upper connection channels 603 are spaced 60 degrees apart.

[0033] According to the ideal gas law in thermodynamics, based on PV=nRT, at the same temperature T, increasing V and decreasing P reduces the internal pressure of the guide, thereby reducing friction. Therefore, the depths of each lower connecting channel 602 and upper connecting channel 603 are greater than the depth of the middle transverse channel 601. By increasing the depth, the overall volume of the bushing mounting cavity 40 connected to the lower connecting channel 602 and the volume of the balance cavity 320 connected to the upper connecting channel 603 are increased to disperse the pressure effect caused by the temperature rise.

[0034] The lower connecting channel 602 and the upper connecting channel 603 are located on the upper and lower sides of the middle transverse channel 601, respectively. There are more than two of each channel, and they are evenly distributed circumferentially. Their depth is greater than that of the middle transverse channel 601. The lower connecting channels 602 and the upper connecting channels 603 are arranged alternately to ensure uniform diffusion of the lubricant.

[0035] like Figures 3-6 As shown, in order to further increase the internal space and facilitate gas flow, the inner wall of the bushing mounting cavity 40 is provided with a number of upper conical grooves 401 and lower conical grooves 402 spaced apart vertically. The lengths of the upper conical grooves 401 and lower conical grooves 402 are the same as the lengths of the upper connecting channel 603 and the lower connecting channel 602, and their numbers correspond one-to-one. The upper conical grooves 401 and lower conical grooves 402 are respectively embedded in the inner wall of the bushing mounting cavity 40, further increasing the space inside the balance cavity 320 and the bushing mounting cavity 40.

[0036] The inner oil seal assembly 5 includes an inner oil seal cavity 50 and an inner oil seal mounting base 51. The inner oil seal ring 52 is snapped into the mounting base 51 and sleeved on the piston rod 13 to prevent internal lubricant leakage and to prevent magnetorheological fluid from entering the guide.

[0037] A guide buffer 14 is provided on the inner end 11 of the guide housing 1. The guide buffer 14 is used to absorb the impact force of the piston rod 13 and the piston during the movement process, and plays a protective role.

[0038] The limiting snap ring 15 is used to fix the position of the guide housing 1, and the outer sealing strip 16 enhances the sealing between the outer guide housing 1 and the shock absorber housing.

[0039] Example 2: Based on Example 1, as follows Figure 8 As shown, there are four lower connecting channels 602 and four upper connecting channels 603 inside the bushing mounting base 6. The length of both the lower connecting channels 602 and the upper connecting channels 603 is greater than half the length of the outer ring 61.

[0040] Example 3: Based on Example 1 or 2, such as Figure 9As shown, there are four lower connecting channels 602 and four upper connecting channels 603 inside the bushing mounting base 6. The lengths of the lower connecting channels 602 and the upper connecting channels 603 are shortened, and the lengths of the lower connecting channels 602 and the upper connecting channels 603 are equal to half the length of the outer ring 61.

[0041] Furthermore, the technical solutions of the various embodiments of this utility model can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by this utility model.

[0042] The above-described embodiments are merely illustrative of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of this utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and these all fall within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the appended claims.

Claims

1. A guide for a magnetorheological damper, characterized in that, The guide housing (1) includes an inner end (11) and an outer end (12), and a connecting hole (10) is provided between the inner end (11) and the outer end (12), the connecting hole (10) being used to place the piston rod (13). In the direction from the outer end (12) to the inner end (11), the guide housing (1) is provided with a dustproof sealing assembly (2), an outer oil seal assembly (3), a bushing assembly (4) and an inner oil seal assembly (5). The bushing assembly (4) includes a bushing mounting cavity (40) and a lubricating fluid cavity (41) that are connected to each other. A bushing mounting seat (6) is provided in the bushing mounting cavity (40). The lubricating fluid cavity (41) is filled with lubricating oil. A bushing (7) is provided in the bushing mounting seat (6). The bushing (7) is slidably fitted with the piston rod (13). A pressure reducing channel (60) and a balance channel (70) are provided in the circumferential direction of the bushing mounting seat (6). The pressure reducing channel (60) and the balance channel (70) are connected to each other through the bushing mounting cavity (40). The guide housing (1) is also provided with a limit snap ring (15) and multiple outer sealing strips (16) on its side wall.

2. The guide of a magnetorheological damper according to claim 1, characterized in that, The dustproof sealing assembly (2) includes a dustproof sealing groove (20) and a dustproof sealing ring (21). The dustproof sealing ring (21) includes a conical isolation cover (211) and an annular connecting part (212). The end of the annular connecting part (212) is engaged with the side wall of the dustproof sealing groove (20).

3. The guide of a magnetorheological damper according to claim 2, characterized in that, The external oil seal assembly (3) includes an external oil seal cavity (30) and an external oil seal ring (31). The external oil seal cavity (30) and the dustproof sealing groove (20) are connected by a connecting hole (10). The external oil seal ring (31) includes an annular snap-fit ​​part (311) and a U-shaped sealing ring (312). One end of the U-shaped sealing ring (312) abuts against the piston rod (13), and the other end of the U-shaped sealing ring (312) abuts against the side wall of the external oil seal cavity (30).

4. The guide of a magnetorheological damper according to claim 3, characterized in that, The bushing mounting base (6) is an annular structure. The bushing mounting base (6) includes an outer ring (61) and an inner ring (62). The bushing (7) is snapped onto the inner ring (62) of the bushing mounting base (6). A balance cavity (320) is formed between the lower surface of the outer oil seal assembly (3) and the upper surface of the bushing mounting base (6). The pressure reducing channel (60) is disposed on the outer ring (61) and communicates with the balance cavity (320). The upper and lower ends of the inner ring (62) are also provided with flow guiding chamfers (621). The balance channel (70) is located between the bushing mounting base (6) and the bushing (7).

5. The guide of a magnetorheological damper according to claim 4, characterized in that, The step-down channel (60) includes a middle transverse channel (601) and several lower connecting channels (602) and upper connecting channels (603) connected to the middle transverse channel (601). The middle transverse channel (601) is located in the middle of the outer ring (61). The middle transverse channel (601) is arranged around the outer ring (61) and connected end to end.

6. The guide of a magnetorheological damper according to claim 5, characterized in that, The number of lower connecting channels (602) and upper connecting channels (603) is equal and there are more than two of each. Each of the lower connecting channels (602) or upper connecting channels (603) is evenly arranged in the circumferential direction of the outer ring (61), and each of the lower connecting channels (602) and upper connecting channels (603) is spaced apart.

7. The guide of a magnetorheological damper according to claim 6, characterized in that, The depth of each of the lower connecting channels (602) and the upper connecting channels (603) is greater than the depth of the middle transverse channel (601).

8. The guide of a magnetorheological damper according to claim 7, characterized in that, The inner wall of the bushing mounting cavity (40) is provided with a plurality of upper conical grooves (401) and lower conical grooves (402) spaced apart vertically. The lengths of the upper conical grooves (401) and lower conical grooves (402) are the same as the lengths of the upper connecting channel (603) and lower connecting channel (602), and their quantities correspond one-to-one.

9. The guide of a magnetorheological damper according to claim 1, characterized in that, The inner oil seal assembly (5) includes an inner oil seal cavity (50) and an inner oil seal mounting seat (51). An inner oil seal ring (52) is snapped onto the inner oil seal mounting seat (51) and the inner oil seal ring (52) is sleeved on the piston rod (13).

10. The guide of a magnetorheological damper according to claim 1, characterized in that, A guide buffer (14) is provided on the inner end (11) of the guide housing (1).

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