Highly sealed long life automotive wheel hub bearing

Abstract

This invention discloses a high-sealing, long-life automotive wheel hub bearing, belonging to the field of bearing technology. The invention includes an inner ring body fixedly mounted on a shaft, an outer ring body disposed on the outer side of the inner ring body, and balls disposed between the inner and outer ring bodies, with the outer sides of the balls positioned by a cage. Pre-set holes are provided on both sides of the inner and outer ring bodies, and an oil reservoir assembly for automatic oil replenishment driven by heat is fixedly installed inside the pre-set holes. Sealing plates are fixedly installed at both ends of the inner ring body, and a first sealing adhesive for oil adjustment and delivery is fixedly bonded to the outer side of the sealing plates. A second sealing adhesive is fixedly installed at both ends of the outer ring body. This high-sealing, long-life automotive wheel hub bearing can employ different sealing methods when the vehicle is moving and stationary, effectively improving the sealing and dust prevention effect at the bearing, and can adaptively add oil during use.

Description

Technical Field

[0001] This invention relates to the field of bearing technology, specifically to a high-sealing, long-life automotive wheel hub bearing. Background Technology

[0002] Automotive wheel bearings are one of the key components of a car. Their main functions are to bear weight and provide precise guidance for the rotation of the wheel hub.

[0003] The prior art (Chinese patent application number: 202221066116.1, application date: 2022-05-06) discloses an automotive wheel hub bearing with good sealing and dustproof performance, including an outer bearing ring and an inner bearing ring. A bearing assembly is rotatably connected to the inner surface of the outer bearing ring, and the inner bearing ring is rotatably connected to the inner surface of the bearing assembly. A sealing sleeve is threadedly fixed to one end of the outer bearing ring, and a sealing device is tumbledly connected to the inner surface of the sealing sleeve. The sealing device is in contact with the inner bearing ring, and the sealing device includes a fixing block, a protective washer, a rotating groove, a ball retainer, and rolling balls. This design helps to seal the bearing connection, preventing dust from mixing with the bearing lubricating oil. Such a mixture easily attracts dirt and other hard particles, which can enter the bearing, damaging its internal structure and ultimately causing damage. Existing technology (Chinese patent application number: 202221470606.8, application date: 2022-06-13) discloses a long-life automotive wheel hub bearing, including a main shaft. A hub flange is fixedly mounted at one end of the main shaft. The outer side of the main shaft has an inverted conical structure, and rollers are evenly mounted on the outer side of the main shaft. An annular structure is formed between the rollers on the outer side of the main shaft. The oil reservoir has an outer ring fitted around the outside of the main shaft, with the inner side of the outer ring contacting the rollers. A sealing ring is fitted at one end of the main shaft, with one side of the sealing ring pressing against one side of the outer ring. By using inclined rollers and vertically installed balls, the load-bearing capacity during use is improved, thereby enhancing the stability of the rotation between the outer ring and the main shaft. The oil reservoir fills the interior of the oil reservoir during use, facilitating the storage of more lubricating grease. Furthermore, the centrifugal force during use helps to squeeze the lubricating grease between the rollers, achieving a high lubrication effect, reducing wear, and extending service life.

[0004] While existing sealing devices for automotive wheel hub bearings can achieve a certain sealing effect during use, they are prone to wear during rotation, which is not conducive to achieving a long-term sealing effect. Consequently, they cannot provide sufficient sealing and dust prevention when the vehicle is in motion or stationary, thus exhibiting certain defects in use. Summary of the Invention

[0005] The purpose of this invention is to provide a high-sealing, long-life automotive wheel bearing to solve the problem mentioned in the background art that although the sealing devices of current automotive wheel bearings on the market can achieve a certain sealing effect during use, they are prone to wear during rotation, which is not conducive to achieving a long-term sealing effect and thus cannot provide sufficient sealing and dust prevention when the vehicle is in motion or stationary.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a high-sealing, long-life automotive wheel hub bearing, comprising an inner ring body fixedly mounted on a shaft, an outer ring body disposed on the outer side of the inner ring body, and balls disposed between the inner ring body and the outer ring body, wherein the outer side of the balls is positioned by a cage, and both the inner ring body and the outer ring body are oil-impregnated porous bearing structures.

[0007] The inner and outer rings have pre-set holes on both sides, and an oil storage component that automatically replenishes oil by being driven by heat is fixedly installed inside the pre-set holes. Sealing sheets are fixedly installed at both ends of the inner ring, and a first sealing adhesive for oil adjustment and transportation is fixedly bonded to the outside of the sealing sheets. A second sealing adhesive is fixedly installed at both ends of the outer ring. The first sealing adhesive also has a bonding part and a collecting part for improving surface sealing. Adhesive blocks are evenly fixed to the outside of the first sealing adhesive.

[0008] Preferably, the oil storage assembly includes a fixed cylinder embedded and fixedly installed inside a preset hole, and a movable cylinder is sleeved on the inner side of the fixed cylinder. A sealing screw is threaded to one end of the fixed cylinder opening, and the inner side of the movable cylinder is pre-filled with lubricating oil.

[0009] Preferably, a memory metal strip is fixedly connected between the outer ends of the fixed cylinder and the movable cylinder, and the memory metal strip is bent. Under the action of heat, the memory metal strip deforms and drives the movable cylinder to rotate.

[0010] Preferably, both the fixed cylinder and the movable cylinder are provided with oil seepage holes evenly distributed, and the initial positions of the oil seepage holes on the fixed cylinder and the movable cylinder are staggered. During the rotation of the movable cylinder, the oil seepage holes on the fixed cylinder gradually connect with the oil seepage holes on the movable cylinder. At the same time, the oil inside the movable cylinder is transported through the porous structure on the inner and outer ring bodies.

[0011] Preferably, a spring is fixedly connected to one end of the sealing screw inside the fixed cylinder, and a rotating component is fixedly connected to the other end of the spring. A pushing ring is rotatably installed on the outer side of the rotating component. The pushing ring is sealed against the inner wall of the movable cylinder. Sealing sheets that fit together and seal are evenly fixedly installed on the inner side of the pushing ring. A limiting frame is fixedly installed on the inner wall of the pushing ring, and the limiting frame restricts the rotation direction of the sealing sheets.

[0012] Preferably, the inner side of the first sealing colloid is a cavity structure, and the outer wall of the first sealing colloid is uniformly and integrally provided with a colloid block, and the outer wall of the colloid block is set with an inclined structure. At the same time, during the rotation of the first sealing colloid, the colloid block pushes the outer side of the first sealing colloid to deform under the action of air pressure, so as to realize the compression of the cavity inside the first sealing colloid.

[0013] Preferably, the second sealing adhesive has an arc-shaped cross-section, and the first sealing adhesive has an arc-shaped cross-section near the side wall of the second sealing adhesive. The arc surfaces of the first and second sealing adhesives are aligned. The bonding portion has an annular structure. In its initial state, the bonding portion is bonded to the second sealing adhesive to achieve a seal. When the outer side of the first sealing adhesive deforms, the bonding portion is driven to detach from the second sealing adhesive to reduce friction.

[0014] Preferably, the outer arc wall of the first sealing colloid is provided with an annular oil-drawing hole, and a first film is integrally provided on the inner side of the first sealing colloid, and the first film is attached to and covers the oil-drawing hole. At the same time, when the first sealing colloid elastically recovers, excess oil inside the outer ring is drawn out through the oil-drawing hole.

[0015] Preferably, the first sealing colloid has oil drain holes evenly distributed on the side facing the second sealing colloid, and a second film is uniformly and integrally disposed on the outer side of the first sealing colloid, and the second film covers the outer side of the oil drain holes to achieve a seal. At the same time, when the first sealing colloid deforms, the oil drain holes are discharged to the outer side of the collection part. The inner side of the first sealing colloid is pre-stored with lubricating oil, and the level of the lubricating oil inside the first sealing colloid is higher than the lowest oil drain hole.

[0016] Compared with the prior art, the beneficial effects of the present invention are: the high-sealing and long-life automotive wheel hub bearing can adopt different sealing methods when the vehicle is running and stopped, effectively improving the sealing and dustproof effect at the bearing, and can adaptively add oil during use, as detailed below;

[0017] 1. Equipped with a fixed cylinder, a movable cylinder, and a shape memory metal strip, when the bearing is not sufficiently lubricated during operation, the temperature inside the bearing will rise due to friction. At this time, the shape memory metal strip will deform under the action of heat, thereby driving the movable cylinder inside the fixed cylinder to rotate, so that the oil seepage holes on the fixed cylinder and the movable cylinder gradually overlap. At the same time, the push ring will move under the action of spring force, thereby pressurizing the oil, so that the lubricating oil can penetrate and be transported through the porous structure on the inner and outer rings, achieving automatic oiling.

[0018] 2. The bearing is provided with a first sealing compound, a second sealing compound, and an adhesive part. The arc-shaped parts corresponding to the first and second sealing compounds can reduce the chance of dust entering the inner side of the bearing. At the same time, when the vehicle is not running, the adhesive part is attached to the first sealing compound, so that the two can fully seal the inner and outer rings. When the vehicle is running, the inner ring drives the first sealing compound to rotate, which can cause the first sealing compound to undergo elastic deformation under the drive of the rubber block, thereby causing the adhesive part to detach from the second sealing compound and avoiding wear between the first and second sealing compounds.

[0019] 3. It is equipped with a collection section, an oil drain hole, and an oil suction hole. As the first sealing colloid rotates and deforms, it will discharge the lubricating oil stored inside through the oil drain hole, so that the oil is stored on the outside of the collection section. At the same time, with the centrifugal force of rotation, the oil can form an oil film structure between the second sealing colloid and the collection section, so that a certain sealing and dust-blocking structure is formed between the second sealing colloid and the collection section, ensuring the sealing effect of the bearing during vehicle operation. When the first sealing colloid is restored, it can automatically extract excess oil from the bearing through the oil suction hole, avoiding excessive oil and increased heat generation. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the main structure of the present invention;

[0021] Figure 2 This is a schematic diagram of the ball and cage mounting structure of the present invention;

[0022] Figure 3 This is a schematic cross-sectional view of the present invention;

[0023] Figure 4 For the present invention Figure 3 Enlarged structural diagram at point A;

[0024] Figure 5 This is a schematic cross-sectional view of the fixed cylinder structure of the present invention;

[0025] Figure 6 This is a schematic cross-sectional view of the fixed cylinder and the movable cylinder of the present invention;

[0026] Figure 7 This is a schematic diagram of the connection structure between the push ring and the sealing film of the present invention;

[0027] Figure 8 This is a schematic diagram of the three-dimensional structure of the first sealing colloid of the present invention;

[0028] Figure 9 For the present invention Figure 8 Enlarged structural diagram at point B.

[0029] In the diagram: 1. Inner ring; 2. Outer ring; 3. Ball bearing; 4. Cage; 5. Preset hole; 6. Fixed cylinder; 7. Moving cylinder; 8. Oil seepage hole; 9. Memory metal strip; 10. Sealing screw; 11. Spring; 12. Rotating component; 13. Push ring; 1301. Limiting frame; 14. Sealing film; 15. Sealing sheet; 16. First sealing adhesive; 17. Second sealing adhesive; 18. Adhesive part; 19. Collection part; 20. Adhesive block; 21. Oil drain hole; 22. Oil suction hole; 23. First film; 24. Second film. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] Example 1: Existing automotive wheel hub bearings are inconvenient to adjust lubricating oil levels according to bearing friction conditions, resulting in insufficient timely replenishment of bearing oil and thus easily leading to bearing wear and reduced lifespan. To solve this technical problem, this example discloses the following technical content, please refer to... Figures 1-3 and Figures 5-7 As shown; a high-sealing, long-life automotive wheel hub bearing includes an inner ring body 1 fixedly mounted on a shaft, an outer ring body 2 disposed on the outer side of the inner ring body 1, and balls 3 disposed between the inner ring body 1 and the outer ring body 2. The outer side of the balls 3 is positioned by a cage 4. Both the inner ring body 1 and the outer ring body 2 are oil-impregnated porous bearing structures. Pre-set holes 5 are opened on both sides of the inner ring body 1 and the outer ring body 2. An oil storage component that automatically replenishes oil by heat is fixedly installed on the inner side of the pre-set holes 5. The oil storage component includes a fixed cylinder 6 embedded and fixedly installed on the inner side of the pre-set holes 5. A movable cylinder 7 is sleeved on the inner side of the fixed cylinder 6. A sealing screw 10 is threaded to one end of the cylinder opening of the fixed cylinder 6. The inner side of the movable cylinder 7 is pre-filled with lubricating oil. A shape memory metal strip 9 is fixedly connected between the outer ends of the fixed cylinder 6 and the movable cylinder 7. The shape memory metal strip 9 is bent and deforms under heat, pushing the movable cylinder 7 to rotate.

[0032] Both the fixed cylinder 6 and the movable cylinder 7 have oil seepage holes 8 evenly distributed on them. The initial positions of the oil seepage holes 8 on the fixed cylinder 6 and the movable cylinder 7 are staggered. During the rotation of the movable cylinder 7, the oil seepage holes 8 on the fixed cylinder 6 gradually connect with the oil seepage holes 8 on the movable cylinder 7. At the same time, the oil inside the movable cylinder 7 is transported through the porous structure on the inner ring body 1 and the outer ring body 2. The sealing screw 10 is fixedly connected to a spring 11 at one end inside the fixed cylinder 6, and the other end of the spring 11 is fixedly connected to a rotating part 12. A push ring 13 is rotatably installed on the outer side of the rotating part 12. The push ring 13 is sealed and fitted against the inner wall of the movable cylinder 7. The inner side of the push ring 13 is evenly fixedly installed with sealing films 14 that fit and seal each other. A limiting frame 1301 is fixedly installed on the inner wall of the push ring 13, and the limiting frame 1301 restricts the rotation direction of the sealing film 14.

[0033] When the vehicle is in motion, the inner ring 1 rotates at high speed. When the oil inside the bearing is insufficient, the bearing operating temperature gradually increases. At this time, the shape memory metal strip 9 will deform under the influence of temperature. During the deformation process, the shape memory metal strip 9 will drive the movable cylinder 7 inside the fixed cylinder 6 to rotate. At this time, the oil seepage holes 8 on the fixed cylinder 6 and the movable cylinder 7 gradually overlap, allowing the oil to contact the inner ring 1 and the outer ring 2 through the oil seepage holes 8. Then, it will permeate and be transported through the porous structure of the inner ring 1 and the outer ring 2. At the same time, the pushing ring 13 and the sealing film 14 will slide along the inner side of the movable cylinder 7 under the elastic force of the spring 11, thereby pressurizing the lubricating oil and accelerating the oil penetration. When the oil is replenished and the bearing operating temperature gradually decreases, the shape memory metal strip 9 will return to its original shape, thereby pulling the movable cylinder 7 to return to its original rotation. At this time, the oil seepage holes 8 on the fixed cylinder 6 and the movable cylinder 7 will interlock and block each other, thereby stopping the continued addition of oil and effectively extending the service life of the automotive wheel hub bearing.

[0034] Example 2: The technical content disclosed in this example is a further improvement based on Example 1. Existing automotive wheel hub bearings suffer from problems such as the sealing cap failing to provide a sufficient seal or the sealing cap being prone to wear, resulting in inadequate dust prevention. To further solve this technical problem, this example discloses the following technical content: Figures 3-4 and Figures 8-9As shown; sealing sheets 15 are fixedly installed at both ends of the inner ring 1, and a first sealing adhesive 16 for oil adjustment and conveying is fixedly bonded to the outer side of the sealing sheet 15. A second sealing adhesive 17 is fixedly installed at both ends of the outer ring 2. The first sealing adhesive 16 also has an adhesive part 18 and a collection part 19 for improving surface sealing. Adhesive blocks 20 are uniformly fixed to the outer side of the first sealing adhesive 16. The inner side of the first sealing adhesive 16 has a cavity structure, and adhesive blocks 20 are uniformly and integrally formed on the outer wall of the first sealing adhesive 16. 0. Furthermore, the outer wall of the adhesive block 20 is designed with a sloping structure. Simultaneously, during the rotation of the first sealing adhesive 16, the adhesive block 20 deforms on the outer side of the first sealing adhesive 16 under air pressure, thereby compressing the inner cavity of the first sealing adhesive 16. The cross-section of the second sealing adhesive 17 is arc-shaped, and the cross-section of the side wall of the first sealing adhesive 16 near the second sealing adhesive 17 is also arc-shaped. The arc surfaces of the first and second sealing adhesives 16 and 17 are aligned, and the fitting portion 18 has an annular structure. The first sealing compound 16 is configured such that the bonding part 18 initially adheres to the second sealing compound 17 to achieve a seal. When the outer side of the first sealing compound 16 deforms, the bonding part 18 is driven to detach from the second sealing compound 17 to reduce friction. An annular oil-drawing hole 22 is provided on the outer arc wall of the first sealing compound 16, and a first adhesive sheet 23 is integrally formed on the inner side of the first sealing compound 16, with the first adhesive sheet 23 adhering to and covering the oil-drawing hole 22. Simultaneously, when the first sealing compound 16 elastically recovers, oil is drawn from the inner side of the outer ring 2 through the oil-drawing hole 22. Excess oil is drained through oil drain holes 21 evenly distributed on the side of the first sealing colloid 16 facing the second sealing colloid 17. A second film 24 is uniformly and integrally disposed on the outer side of the first sealing colloid 16, and the second film 24 covers the outer side of the oil drain holes 21 to achieve a seal. At the same time, when the first sealing colloid 16 deforms, it drains through the oil drain holes 21 to the outer side of the collection part 19. Lubricating oil is pre-stored on the inner side of the first sealing colloid 16, and the level of the lubricating oil on the inner side of the first sealing colloid 16 is higher than the lowest oil drain hole 21.

[0035] When the vehicle is parked, the fitting part 18 is attached to the second sealing adhesive 17, thereby enabling the first sealing adhesive 16, the second sealing adhesive 17, and the fitting part 18 to provide a sufficient static seal between the inner ring body 1 and the outer ring body 2, preventing external dust and other impurities from entering the bearing and accelerating wear. When the vehicle is in motion, the inner ring body 1 will drive the first sealing adhesive 16 to rotate at high speed through the sealing plate 15. At this time, the rubber block 20 on the outside of the first sealing adhesive 16 will push the first sealing adhesive 16 to undergo elastic deformation under air pressure, thereby deforming the cavity inside the first sealing adhesive 16. At this time, the first sealing adhesive 16 can discharge lubricant into the collection part 19 through the oil drain hole 21. As the first sealing colloid 16 and the collecting part 19 rotate at high speed, a dust-blocking structure is formed between them due to the lubricating oil. At the same time, the corresponding curved structures on the first sealing colloid 16 and the second sealing colloid 17 can further improve the dynamic dust prevention at the bearing during vehicle operation. When the vehicle stops, the first sealing colloid 16 will elastically recover, so that the first sealing colloid 16 can automatically draw excess lubricating oil from the inside of the bearing through the oil suction hole 22, avoiding excessive oil and increasing rotational resistance, and preventing excessive heat generation. The first film 23 and the second film 24 can block the oil drain hole 21 and the oil suction hole 22 to realize a one-way valve structure.

[0036] The contents not described in detail in this specification are existing technologies known to those skilled in the art.

[0037] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A high-sealing, long-life automotive wheel hub bearing, comprising an inner ring body (1) fixedly mounted on a shaft, an outer ring body (2) provided on the outer side of the inner ring body (1), and balls (3) provided between the inner ring body (1) and the outer ring body (2), and the outer side of the balls (3) being positioned by a cage (4), while both the inner ring body (1) and the outer ring body (2) are oil-impregnated porous bearing structures; Its features are, The inner ring (1) and outer ring (2) are provided with preset holes (5) on both sides, and an oil storage component that automatically replenishes oil by heat is fixedly installed on the inner side of the preset holes (5). The two ends of the inner ring (1) are fixedly installed with sealing sheets (15), and the outer side of the sealing sheets (15) is fixedly bonded with a first sealing adhesive (16) for oil adjustment and transportation. The two ends of the outer ring (2) are fixedly installed with a second sealing adhesive (17). At the same time, the first sealing adhesive (16) is also provided with a bonding part (18) and a collecting part (19) for improving the surface sealing performance. The outer side of the first sealing adhesive (16) is uniformly fixed with adhesive blocks (20).

2. The high-sealing, long-life automotive wheel hub bearing according to claim 1, characterized in that: The oil storage assembly includes a fixed cylinder (6) embedded and fixedly installed inside a preset hole (5), and a movable cylinder (7) is sleeved on the inner side of the fixed cylinder (6). A sealing screw (10) is threaded to one end of the cylinder opening of the fixed cylinder (6), and the inner side of the movable cylinder (7) is pre-filled with lubricating oil.

3. The high-sealing, long-life automotive wheel hub bearing according to claim 2, characterized in that: A memory metal strip (9) is fixedly connected between the outer ends of the fixed cylinder (6) and the movable cylinder (7), and the memory metal strip (9) is bent. Under the action of heat, the memory metal strip (9) deforms and pushes the movable cylinder (7) to rotate.

4. The high-sealing, long-life automotive wheel hub bearing according to claim 3, characterized in that: Oil seepage holes (8) are evenly provided on both the fixed cylinder (6) and the movable cylinder (7), and the initial positions of the oil seepage holes (8) on the fixed cylinder (6) and the movable cylinder (7) are staggered. During the rotation of the movable cylinder (7), it gradually connects with the oil seepage holes (8) on the fixed cylinder (6). At the same time, the oil inside the movable cylinder (7) is transported through the porous structure on the inner ring body (1) and the outer ring body (2).

5. The high-sealing, long-life automotive wheel hub bearing according to claim 2, characterized in that: The sealing screw (10) is fixedly connected to a spring (11) at one end inside the fixed cylinder (6), and a rotating part (12) is fixedly connected to the other end of the spring (11). A push ring (13) is rotatably installed on the outer side of the rotating part (12). The push ring (13) is sealed against the inner wall of the movable cylinder (7). A sealing film (14) is evenly fixedly installed on the inner side of the push ring (13). A limiting frame (1301) is fixedly installed on the inner wall of the push ring (13), and the limiting frame (1301) restricts the rotation direction of the sealing film (14).

6. The high-sealing, long-life automotive wheel hub bearing according to claim 1, characterized in that: The inner side of the first sealing colloid (16) is a cavity structure, and the outer wall of the first sealing colloid (16) is uniformly and integrally provided with a colloid block (20), and the outer wall of the colloid block (20) is set with a sloping structure. At the same time, during the rotation of the first sealing colloid (16), the colloid block (20) is pushed by air pressure to deform the outer side of the first sealing colloid (16) so as to achieve the compression of the cavity inside the first sealing colloid (16).

7. A high-sealing, long-life automotive wheel hub bearing according to claim 6, characterized in that: The second sealing colloid (17) has an arc-shaped cross-section, and the first sealing colloid (16) has an arc-shaped cross-section near the side wall of the second sealing colloid (17). The arc surfaces of the first sealing colloid (16) and the second sealing colloid (17) are aligned. The bonding part (18) has an annular structure. In the initial state, the bonding part (18) is bonded to the second sealing colloid (17) to achieve a seal. When the outer side of the first sealing colloid (16) deforms, the bonding part (18) is driven to detach from the second sealing colloid (17) to reduce friction.

8. A high-sealing, long-life automotive wheel hub bearing according to claim 6, characterized in that: The first sealing colloid (16) has an annular oil-drawing hole (22) on its outer arc wall, and a first film (23) is integrally provided on the inner side of the first sealing colloid (16). The first film (23) is attached to and covers the oil-drawing hole (22). At the same time, when the first sealing colloid (16) elastically recovers, it draws out the excess oil from the inner side of the outer ring body (2) through the oil-drawing hole (22).

9. A high-sealing, long-life automotive wheel hub bearing according to claim 6, characterized in that: The first sealing colloid (16) has oil drain holes (21) evenly opened on the side facing the second sealing colloid (17), and a second film (24) is evenly and integrally disposed on the outer side of the first sealing colloid (16). The second film (24) covers the outer side of the oil drain hole (21) to achieve sealing. At the same time, when the first sealing colloid (16) deforms, it is discharged to the outer side of the collection part (19) through the oil drain hole (21). The inner side of the first sealing colloid (16) is pre-stored with lubricating oil, and the liquid level of the lubricating oil inside the first sealing colloid (16) is higher than the lowest oil drain hole (21).

Images