A sealing structure for a wheel hub bearing

Abstract

A sealing structure of a wheel hub bearing comprises a flange and a flange outer ring, a sealing assembly is arranged between the flange and the flange outer ring, the sealing assembly comprises a sealing cover and a sealing ring, the sealing cover rotates together with the flange, the sealing ring is fixed to the flange outer ring and is stationary compared to the flange, a sealing lip is arranged on the sealing ring towards the sealing cover to form a sealing contact with the sealing cover, a clamping column is arranged on the flange outer ring, a U-shaped clamping groove with its opening facing the axial direction is arranged on the sealing ring corresponding to the clamping column, and the clamping groove cooperates with the clamping column to prevent the sealing ring from axially and radially offsetting during the operation of the wheel hub bearing. The beneficial effect of the present invention is that hiding the sealing lip between the sealing cover and the sealing ring can not only reduce the interference of external influences on the sealing lip as much as possible through the space design between the sealing cover and the sealing ring, but also because the sealing lip directly contacts the sealing cover instead of the flange, it can also prevent the wear of the sealing contact of the sealing lip caused by rust of the flange at the same time.

Description

Technical Field

[0001] The present invention relates to the field of sealing structures, and in particular to a sealing structure of a hub bearing. Background Art

[0002] The sealing structure of a wheel hub bearing is crucial for preventing the intrusion of external sediment, dust, and moisture into the bearing and preventing grease leakage. High-performance seals must offer excellent grease leakage resistance, as well as excellent heat resistance, mud, and sewage resistance. Sealing structures have evolved from single-piece to two-piece seals. Currently, the most commonly used seal is the integral seal, consisting of a dust cover and a sealing ring. This integral seal structure is widely used for its low friction torque, simple structure, easy assembly, and excellent sealing performance.

[0003] Chinese patent document CN115929797A discloses a wheel hub bearing sealing structure comprising a bearing, a sealing ring, and a flange. The sealing ring is fitted over the outer circumference of the bearing, with the inner circumference of the end portion contacting the outer circumference of the bearing. The flange is fitted over the end of the bearing and connected to the bearing, with the sealing ring located between the flange and the bearing. The sealing ring comprises a first sealing portion, the flange comprises a first pressing portion, and the first pressing portion is pressed against the first sealing portion. The sealing ring comprises a second sealing portion, the flange comprises a second pressing portion, and the second pressing portion is pressed against the second sealing portion. The sealing ring comprises a third sealing portion, the flange comprises a third pressing portion, and the third pressing portion is pressed against the third sealing portion.

[0004] The above solution enhances waterproof and dustproof performance by creating a sealed contact between multiple sealing parts and the flange. However, this solution has the following drawbacks: First, due to the excessive number of sealing parts, the rotational torque generated during rotation exceeds the low torque requirement of existing new energy vehicles; second, the contact points between the sealing parts and the flange are exposed to environmental influences, causing wear of the sealing parts at the contact points due to cement, sand, etc., and the flange, due to its material, is prone to rust when exposed to water vapor, further wearing the sealing parts, affecting the sealing effect of the sealing parts. Summary of the Invention

[0005] In view of the deficiencies in the prior art, the present invention provides a sealing structure for a hub bearing that can reduce the impact of environmental factors on the sealing contact.

[0006] To achieve the above-mentioned purpose, the technical solution of the present invention is as follows: A sealing structure of a wheel hub bearing, comprising a flange and a flange outer ring, a sealing assembly is arranged between the flange and the flange outer ring, the sealing assembly comprises a sealing cover and a sealing ring, the sealing cover is fixed to the flange and rotates with the flange, the sealing ring is fixed to the flange outer ring and is stationary compared to the flange, a sealing lip is provided on the sealing ring facing the sealing cover to form a sealing contact therewith, a clamping column is provided on the flange outer ring, and a U-shaped clamping groove with its opening facing axially is provided on the sealing ring corresponding to the clamping column, the clamping groove cooperates with the clamping column to prevent the sealing ring from axially and radially offset during the operation of the wheel hub bearing.

[0007] The beneficial effects of the present invention are as follows: hiding the sealing lip between the sealing cover and the sealing ring can not only reduce the interference of external influences on the sealing lip as much as possible through the space design between the sealing cover and the sealing ring, but also prevent the wear of the sealing contact of the sealing lip caused by rust of the flange due to the direct contact of the sealing lip rather than the flange; in addition, since the sealing lip is arranged between the sealing cover and the sealing ring and the sealing cover and the sealing ring are respectively fixed to the flange and the flange outer ring, the number of sealing lips used for sealing can be effectively reduced to reduce the rotational torque generated during the rotation process; finally, since only the sealing cover in the sealing assembly will rotate, the torque generated during the rotation is transmitted from the sealing lip to the sealing ring, but the transmission torque can be absorbed due to the cooperation between the sealing ring and the flange outer ring through the clamping column and the clamping groove, so as to prevent the contact position of the sealing lip and the sealing cover from being offset and failing.

[0008] Furthermore, the sealing ring includes a frame and a water retaining lip provided on the frame, the two end faces of the clamping groove in radial contact with the clamping column are the frame and the water retaining lip respectively, and the frame and the water retaining lip form an interference fit with the clamping column respectively.

[0009] The interference fit formed between the frame and the water retaining lip and the clamping column can effectively prevent the sealing lip from radial deviation, and effectively ensure that the sealing lip will not fail in the operation process.

[0010] Furthermore, a plurality of contact protrusions are provided on the water retaining lip, and an interference fit is formed between each of the contact protrusions and the clamping column.

[0011] In the present application, the water retaining lip and the sealing lip can naturally be made of an elastic material. Therefore, the contact protrusions provided on the water retaining lip can not only enhance the friction between the water retaining lip and the clamping column, but also absorb the radial vibration generated by the sealing ring, thereby stabilizing the position of the sealing ring to prevent the sealing lip from shifting during operation.

[0012] Furthermore, the sealing ring is provided with a water-blocking lip located between the sealing ring and the sealing cover. The water-blocking lip and the water-retaining lip form a flow-blocking space, and the flow-blocking space is located above the sealing lip in the radial direction.

[0013] The flow-blocking space further improves the working environment of the sealing lip. Even if external impurities such as water, mud and sand enter the space between the sealing cover and the sealing ring, they will be blocked by the flow-blocking space and will not affect the sealing lip protected by the flow-blocking space. This further reduces the environmental impact on the sealing lip during operation, thereby improving the sealing stability and the service life of the hub bearing.

[0014] Furthermore, the water-blocking lip is arranged to be inclined toward the axial direction away from the outer ring of the flange, and a water-blocking protrusion extending in the radial direction is provided at the end of the water-blocking lip away from the sealing ring.

[0015] The inclined water-blocking lip and the water-blocking protrusion at its end form another labyrinth at the end of the flow-blocking space, thereby further improving the function of the flow-blocking space in preventing external impurities from affecting the sealing lip.

[0016] Furthermore, the flow blocking space includes a first flow blocking area and a second flow blocking area which are connected to form an L-shape. The first flow blocking area is close to the water blocking lip and is arranged axially. The second flow blocking area is close to the water blocking lip and has several reflux grooves on the side close to the sealing ring.

[0017] After the external fluid enters the flow-blocking space, it will first enter the first flow-blocking area arranged along the axial extension. At this time, the centrifugal force will make it difficult for the external fluid to enter the second flow-blocking area even if it enters the flow-blocking space; even if the external fluid enters the second flow-blocking area, the several reflux grooves arranged in the second flow-blocking area will form several small mazes, thereby further preventing the external fluid from affecting the sealing effect of the sealing lip.

[0018] Furthermore, a flow channel leading from the outside to the first flow blocking area is formed between the sealing cover and the water retaining lip. The end surface of one side of the flow channel formed by the water retaining lip is inclined, and the inclined setting makes the cross-sectional width of the flow channel gradually decrease toward the first flow blocking area.

[0019] The end face of one side of the flow channel formed by the water retaining lip is arranged to extend radially, thereby effectively preventing external fluid from invading the flow resistance space along the axial direction, and the end face of one side of the flow channel formed by the water retaining lip is arranged to be inclined, and the inclined setting makes the cross-sectional width of the flow channel gradually shrink toward the first flow resistance area. Since it is in a relatively static state, the width of its contracted cross-sectional width will not change, thereby better preventing external fluid from invading.

[0020] Furthermore, the sealing cover is provided with a contact plate which does not form contact with the flange, the sealing lip forms a sealing contact with the contact plate, and the contact area between the sealing lip and the contact plate increases as the sealing lip moves toward the axial direction of the flange outer ring.

[0021] The contact plate, which is not in contact with the flange, effectively reduces the contact area between the sealing cover and the flange, thereby reducing friction if the flange and the sealing cover become loose. Furthermore, the contact plate forms the skeleton of the sealing cover, which is typically made of rust-resistant SUS430 steel. Even if external fluid breaks through the flow barrier and enters the sealing lip, it will not rust the contact plate and cause excessive wear on the sealing lip. Furthermore, if external fluid enters the sealing lip, the pressure exerted by its own weight on the sealing lip increases the contact area between the sealing lip and the contact plate, thereby partially offsetting any wear on the sealing lip caused by the external fluid.

[0022] Furthermore, the contact plate and the sealing lip are both arranged at an inclination, and after the sealing lip forms a sealing contact with the contact plate, the sealing lip is arranged at an inclination toward the axial direction away from the outer ring of the flange.

[0023] The angled sealing lip more effectively fits the contact plate, forming a tight seal and reducing the intrusion of external contaminants and moisture. Furthermore, the angled design helps to remove impurities such as mud and sand from the contact area during wheel hub rotation, reducing wear between the sealing lip and the contact plate and extending the service life of the seal assembly. Furthermore, the angled design of the sealing lip reduces both its size and the contact area with the contact plate, thereby reducing friction and wear, and minimizing energy loss. Furthermore, the angled sealing lip better distributes pressure from the contact plate, reducing localized stress concentration and enhancing the durability of the seal assembly.

[0024] Furthermore, the sealing cover also includes sealing protrusions and anti-slip plates on the upper and lower sides of the contact plate in the radial direction. After the sealing protrusions form a sealing contact with the flange, the sealing protrusions are inclined toward the axial direction away from the flange; the anti-slip plate is arranged along the axial direction and an interference fit is formed between the anti-slip plate and the flange. A clamping portion is provided at the end of the anti-slip plate away from the contact plate, and a corresponding clamping portion on the flange is provided with a clamping groove that cooperates with it to form a clamping fixation.

[0025] After the sealing protrusion forms a sealing contact with the flange, it is tilted away from the flange's axis. This enhances sealing performance and effectively prevents the intrusion of contaminants and moisture, providing initial protection for the contact plate and reducing the possibility of material deterioration from external contact. Furthermore, the axial placement of the anti-slip plate and its interference fit with the flange provide additional fixing strength, preventing the sealing cover from shifting or falling off during bearing operation. The design of the clip and slot further ensures the stable fixation between the anti-slip plate and the flange. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a cross-sectional view of embodiment 1 of the present invention;

[0027] Figure 2 This is a partial enlarged view of the sealing component of Example 1 of the present invention;

[0028] Figure 3 This is a partial enlarged view of the clamping post of Example 1 of the present invention;

[0029] Figure 4 This is a partial enlarged view of the flow-blocking space in Example 1 of the present invention;

[0030] Figure 5 This is a partial enlarged view of the anti-slip plate of Example 1 of the present invention;

[0031] Figure 6 This is a partial enlarged view of the sealing convex point of Example 1 of the present invention;

[0032] Figure 7 This is a schematic diagram of the dimensions of various locations of the flow-blocking space in Example 1 of the present invention;

[0033] Figure 8 This is a partial enlarged view of the flow-blocking space in Example 2 of the present invention.

[0034] Description of the drawings: 1-flange; 11-slot; 2-flange outer ring; 21-clamping column; 3-sealing assembly; 31-sealing cover; 311-sealing cover frame; 3111-contact plate; 3112-anti-slip plate; 3113-clamping portion; 3114-protruding point; 312-sealing component; 3121-sealing protrusion; 3122-sealing retaining ring; 32-sealing ring; 321-sealing ring frame; 322-water-blocking lip; 3221-contact protrusion; 323-water-blocking lip; 3231-water-blocking protrusion; 324-sealing lip; 325-clamping groove; 33-flow-blocking space; 331-first flow-blocking area; 332-second flow-blocking area; 333-return groove; 3331-flat surface; 3332-arc surface; 334-flow channel. DETAILED DESCRIPTION

[0035] Embodiment 1 of the present invention is a sealing structure of a hub bearing as shown in FIG. Figure 1-7 As shown: it includes a flange 1, a flange outer ring 2 and a sealing assembly 3. The sealing assembly 3 includes a sealing cover 31 fixed to the flange 1 and rotating therewith, and a sealing ring 32 fixed to the flange outer ring 2 and stationary relative to the flange 1.

[0036] The sealing cover 31 includes a sealing cover frame 311 made of SUS430 and a sealing component 312 made of NBR, which is arranged on the sealing cover frame 311. The sealing cover frame 311 includes a contact plate 3111 and an anti-slip plate 3112. The sealing component 312 includes a sealing bump 3121 and a sealing retaining ring 3122. The sealing retaining ring 3122, the sealing bump 3121, the contact plate 3111, and the anti-slip plate 3112 are arranged radially from top to bottom on the sealing cover 31.

[0037] The sealing ring 32 includes a sealing ring frame 321 made of SPCC and a water-blocking lip 322, a water-blocking lip 323, and a sealing lip 324 made of NBR, respectively, disposed on the sealing ring frame 321. The water-blocking lips 322, 323, and sealing lips 324 are radially arranged from top to bottom on the sealing ring 32. A flow-blocking space 33 is formed between the water-blocking lips 323 and 322 to prevent the intrusion of external fluids.

[0038] The present embodiment is described below from the radial direction of the sealing component 3 from top to bottom:

[0039] A flow channel 334 is formed between the sealing ring 3122 and the water-blocking lip 322, leading from the outside to the flow-blocking space 33. The end face of the flow channel 334 formed by the water-blocking lip 322 is inclined, and this inclination causes the cross-sectional width of the flow channel 334 to gradually decrease toward the flow-blocking space 33. The flow-blocking space 33 includes a first flow-blocking area 331 and a second flow-blocking area 332 that are connected to form an L-shape. The first flow-blocking area 331 is connected to the flow channel 334 and is distributed along the axial direction. The second flow-blocking area 332 is close to the water-blocking lip 323 and has a plurality of return grooves 333 on the side close to the sealing ring 32. The dimensions of each part of the flow-blocking space 33 are as follows: Figure 7 As shown, the cross-sectional width of the flow channel 334 (ie Figure 7 A) is 0.4-1.2 mm, and the cross-sectional width of the first flow-blocking area 331 and the second flow-blocking area 332 (i.e. Figure 7(B and C) are 0.4-1.0 mm. The sealing ring 32 has a U-shaped, axially-oriented snap-in groove 325 formed radially between the water-retaining lip 322 and the water-blocking lip 323. A snap-in post 21 is provided on the flange outer ring 2 corresponding to the snap-in groove 325. The two radially contacting end surfaces of the snap-in groove 325 and the snap-in post 21 are the sealing ring skeleton 321 and the water-retaining lip 322, respectively. The water-retaining lip 322 is provided with a plurality of contact protrusions 3221, each of which forms an interference fit with the snap-in post 21, thereby forming an interference fit between the water-retaining lip 322 and the snap-in post 21. On the other side of the snap-in groove 325, the sealing ring skeleton 321 also forms an interference fit with the snap-in post 21. The end of the flow-blocking space 33 within the sealing cover 31 and sealing ring 32 is a water-blocking lip 323, which is tilted away from the axis of the flange outer ring 2. A radially extending water-blocking protrusion 3231 is provided at the end of the water-blocking lip 323, away from the sealing ring 32. The sealing ring 32 has a sealing lip 324 radially below the water-blocking lip 323. This lip forms a sealing contact with a similarly tilted contact plate 3111, which is not in contact with the flange 1. After the sealing contact with the contact plate 3111 is established, the sealing lip 324 is tilted away from the axis of the flange outer ring 2.

[0040] On one side of the sealing cover 31, after a sealing contact is formed between the sealing protrusion 3121 and the flange 1, the sealing protrusion 3121 is tilted toward the axial direction away from the flange 1 to protect the contact plate 3111 and the anti-slip plate 3112 located radially below it (the design of the contact plate 3111 has been mentioned above and will not be elaborated on here). The anti-slip plate 3112 is distributed along the axial direction and an interference fit is formed between the anti-slip plate 3112 and the flange 1. A clamping portion 3113 is provided at the end of the anti-slip plate 3112 away from the contact plate 3111, and a corresponding clamping groove 11 is provided on the flange 1 to cooperate with the clamping portion 3113 to form a clamping fixation.

[0041] During actual operation of this embodiment, the sealing cover 31 is driven to rotate by the flange 1, while the flange outer ring 2 and the sealing ring 32 are stationary relative to the flange 1 and the sealing cover 31, so that only the sealing lip 324 generates a rotational torque during the rotation process, thereby reducing the contact torque generated by the sealing contact during operation; in addition, the flow-blocking space 33 can prevent the external fluid from affecting the sealing lip 324 during operation, thereby providing a good working environment for the sealing lip 324.

[0042] The sealing structure of a hub bearing in the embodiment 2 of the present invention is different from that in the embodiment 1 as follows: Figure 8As shown, several protrusions 3114 are circumferentially arranged on the sealing cover frame 311. Each protrusion 3114 can contact the water-blocking lip 323, and the contact point between the protrusion 3114 and the water-blocking lip 323 is located at the connection between the end of the water-blocking lip 323 and the water-blocking protrusion 3231. Several reflow grooves 333 are provided on one side of the second flow-blocking region 332. The side near the water-blocking lip 323 is configured as a flat surface 3331, and an arcuate surface 3332 is formed opposite the flat surface 3331.

[0043] During use, the sealing cover 31 rotates relative to the sealing ring 32. When the sealing cover 31 rotates until the protruding point 3114 contacts the water-blocking lip 323, the contact force causes the water-blocking lip 323 to bounce, thereby repelling external fluid that has reached it due to centrifugal force into the reflow groove 333. As an optimization, the reflow groove 333 closest to the water-blocking lip 323 can be positioned in the direction of the torque generated by the contact between the protruding point 3114 and the water-blocking lip 323. When the external fluid reaches the reflow groove 333, the curved surface 3332 on the side away from the water-blocking lip 323 acts to collect the external fluid. As the vibration generated by the contact between the protruding point 3114 and the water-blocking lip 323 is transmitted to the reflow groove 333, the flat surface 3331 vibrates, throwing the fluid in the reflow groove 333 out into the reflow groove 333 further away from the water-blocking lip, thus circulating the external fluid away from the second flow-blocking area 332.

[0044] The above embodiment is only one preferred embodiment of the present invention. Common changes and substitutions made by those skilled in the art within the scope of the technical solution of the present invention are all included in the protection scope of the present invention.

Claims

1. A sealing structure of a hub bearing, comprising a flange and a flange outer ring, a sealing assembly is arranged between the flange and the flange outer ring, the sealing assembly comprises a sealing cover and a sealing ring, the sealing cover is fixed to the flange and rotates with the flange, the sealing ring is fixed to the flange outer ring and is stationary compared to the flange, characterized in that: The sealing ring is provided with a sealing lip which forms a sealing contact with the sealing cover in the direction of the sealing ring, and a clamping column is provided on the outer ring of the flange, and a U-shaped clamping groove with its opening facing the axial direction is provided on the sealing ring corresponding to the clamping column, and the clamping groove cooperates with the clamping column to prevent the sealing ring from axially and radially offsetting during the operation of the wheel hub bearing; the sealing ring comprises a skeleton and a water retaining lip provided on the skeleton, the part of the water retaining lip extending along the axial direction is wrapped with the skeleton, and the two end surfaces of the clamping groove which contact with the clamping column in the radial direction are the skeleton and the water retaining lip respectively, and the skeleton and the part of the water retaining lip wrapped with the skeleton form an interference fit with the clamping column respectively; the sealing cover is provided with a contact plate which does not form contact with the flange, and a sealing contact is formed between the sealing lip and the contact plate, and the contact area between the sealing lip and the contact plate increases as the sealing lip moves toward the axial direction of the outer ring of the flange; the sealing cover also includes The sealing protrusions and anti-slip plates are arranged on the upper and lower sides of the contact plate in the radial direction. After the sealing protrusions form a sealing contact with the flange, the sealing protrusions are inclined toward the axial direction away from the flange; the contact plate and the sealing lip are both inclined. After the sealing lip forms a sealing contact with the contact plate, the sealing lip is inclined toward the axial direction away from the outer ring of the flange; the anti-slip plate is arranged in the axial direction and an interference fit is formed between the anti-slip plate and the flange. A clamping portion is arranged at the end of the anti-slip plate away from the contact plate, and a corresponding clamping portion on the flange is provided with a clamping groove that cooperates with it to form a clamping fixation; the sealing cover frame includes a vertical plate, and a space for the sealing protrusion to be tilted and deformed is provided between the sealing protrusions and the vertical plate. A plurality of protrusions are arranged on the sealing cover frame along the circumferential direction, each of which can contact the water-blocking lip, and the contact point between the protrusion and the water-blocking lip is located at the connection between the end of the water-blocking lip and the water-blocking protrusion; A plurality of reflow grooves arranged on one side of the second flow blocking area have a flat surface on one side close to the water blocking lip, and an arc surface is formed opposite to the flat surface.

2. A wheel hub bearing sealing structure according to claim 1, characterized in that: A plurality of contact protrusions are arranged on the water retaining lip, and an interference fit is formed between each of the contact protrusions and the clamping column.

3. The sealing structure of a hub bearing according to claim 1, characterized in that: The sealing ring is provided with a water blocking lip located between the sealing ring and the sealing cover. The water blocking lip and the water retaining lip form a flow blocking space, and the flow blocking space is located above the sealing lip in the radial direction.

4. A wheel hub bearing sealing structure according to claim 3, characterized in that: The water blocking lip is arranged to be inclined toward the axial direction away from the outer ring of the flange, and a water blocking protrusion extending in the radial direction is arranged at the end of the water blocking lip away from the sealing ring.

5. The sealing structure of a hub bearing according to claim 3, characterized in that: The flow blocking space includes a first flow blocking area and a second flow blocking area which are connected to form an L shape. The first flow blocking area is close to the water blocking lip and is arranged along the axial direction. The second flow blocking area is close to the water blocking lip and has a plurality of reflux grooves arranged on the side close to the sealing ring.

6. A wheel hub bearing sealing structure according to claim 5, characterized in that: A flow channel leading from the outside to the first flow blocking area is formed between the sealing cover and the water retaining lip. The end surface of one side of the flow channel formed by the water retaining lip is inclined and the inclined setting makes the cross-sectional width of the flow channel gradually decrease toward the first flow blocking area.

Images