Sealing structure of hub bearing

Abstract

A sealing structure of a hub bearing comprises a flange plate and a flange outer ring, a sealing assembly is arranged between the flange plate and the flange outer ring and comprises a sealing cover and a sealing ring, the sealing cover rotates along with the flange plate, and the sealing ring is fixed to the flange outer ring and is static relative to the flange plate. A sealing lip in sealing contact with the sealing ring is arranged on the sealing ring in the direction facing the sealing cover, a clamping column is arranged on the flange outer ring, a U-shaped clamping groove is formed in the position, corresponding to the clamping column, of the sealing ring, and an opening of the clamping groove faces the axial direction. And the clamping grooves are matched with the clamping columns so as to prevent the sealing rings from axially and radially deviating in the running process of the hub bearing. The sealing structure has the beneficial effects that the sealing lip is hidden between the sealing cover and the sealing ring, so that the interference of external influence on the sealing lip can be reduced as much as possible through the space design between the sealing cover and the sealing ring; as the sealing lip is in direct contact with the sealing cover, the flange can be prevented from being rusted, and the abrasion influence on the sealing contact part of the sealing lip can be prevented.

Description

Technical Field

[0001] The 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 the wheel hub bearing is crucial to prevent external sand, dust and water vapor from invading the bearing and preventing grease leakage. High-performance seals must have good grease leakage prevention performance, and must also have good heat resistance, mud and sewage resistance. The development of the sealing structure has gone through a process from a single-piece sealing structure to a double-piece sealing structure. Currently, the most commonly used is the integral sealing structure, that is, a sealing structure with a dust cover and a sealing ring. This integral sealing structure is widely used for its low friction torque, simple structure, easy assembly and good sealing effect.

[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 sleeved on the outer periphery of the bearing and the inner peripheral surface of the port part is in contact with the outer periphery of the bearing; the flange is sleeved on the end of the bearing and connected to the bearing, and the sealing ring is located between the flange and the bearing; the sealing ring has a first sealing portion, the flange has a first pressing portion, and the first pressing portion is pressed on the first sealing portion; the sealing ring has a second sealing portion, the flange has a second pressing portion, and the second pressing portion is pressed on the second sealing portion; the sealing ring has a third sealing portion, the flange has a third pressing portion, and the third pressing portion is pressed on the third sealing portion.

[0004] The above scheme forms a sealing contact between multiple sealing parts and flanges to enhance the waterproof and dustproof effect. However, the above scheme has the following shortcomings: first, due to the excessive number of sealing parts, the rotational torque generated during the rotation process will be greater than the low torque requirement of existing new energy vehicles; second, the contact positions between the sealing parts and the flanges are all exposed to environmental influences, which will not only cause wear of the sealing parts due to cement or sand, but also the flanges are prone to rust when exposed to water vapor due to their material problems, which will further cause wear to the sealing parts, thereby 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 which can reduce the influence 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 plate and a flange outer ring, a sealing assembly is arranged between the flange plate and the flange outer ring, the sealing assembly comprises a sealing cover and a sealing ring, the sealing cover is fixed to the flange plate and rotates with the flange plate, the sealing ring is fixed to the flange outer ring and is stationary compared to the flange plate, 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, and a U-shaped clamping groove with its opening facing the axial direction is arranged 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 transmitted 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 arranged on the frame, and the two end faces of the clamping groove and the clamping column in radial contact 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 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 sealing during operation.

[0010] Furthermore, 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.

[0011] In the present application, the water retaining lip, the sealing lip, etc. can naturally be made of elastic materials. Therefore, the contact protrusions arranged 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 deflecting 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 choke space further improves the working environment of the sealing lip. Even if external impurities such as water flow, mud and sand enter the space between the sealing cover and the sealing ring, they will be blocked by the choke space and will not act on the sealing lip protected by the choke space, thereby further reducing the environmental impact on the sealing lip during operation, improving the sealing stability and the service life of the wheel 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 arranged at the end of the water blocking lip away from the sealing ring.

[0015] The water-blocking lip is arranged obliquely and the water-blocking protrusion is located at the end thereof, so that the flow-blocking space forms another labyrinth at its end point, 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, and 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.

[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, several small mazes will be formed due to the several reflux grooves arranged in the second flow-blocking area, so as to further prevent 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 blocking 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 arrangement makes the cross-sectional width of the flow channel gradually shrink toward the first flow blocking 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, a contact plate which is not in contact with the flange is provided on the sealing cover, 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 flange outer ring.

[0021] The contact plate that is not in contact with the flange can effectively reduce the contact area between the sealing cover and the flange, so as to reduce the friction between the two when the flange and the sealing cover become loose. In addition, the contact plate is part of the skeleton of the sealing cover, and the skeleton of the sealing cover is usually made of SUS430 with better rust resistance. Even if external fluid breaks through the flow-blocking space and enters the sealing lip, the contact plate will not rust and cause excessive wear on the sealing lip. Moreover, if the external fluid enters the sealing lip, the pressure exerted on the sealing lip by its own gravity will increase the contact area between the sealing lip and the contact plate, thereby offsetting part of the wear of 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 an axial direction away from the outer ring of the flange.

[0023] The inclined sealing lip can fit the contact plate more effectively, forming a tight seal and reducing the intrusion of external pollutants and moisture. In addition, the inclined design helps to throw impurities such as mud and sand out of the contact area when the wheel hub rotates, reducing the wear between the sealing lip and the contact plate and extending the service life of the sealing assembly. Furthermore, due to the inclined design of the sealing lip, the size of the sealing lip can be reduced while also reducing the contact area with the contact plate, thereby reducing friction and wear and reducing energy loss. In addition, the inclined sealing lip can better disperse the pressure under the pressure of the contact plate, reduce local stress concentration, and improve the durability of the sealing 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 axial direction of the flange, which enhances the sealing performance and effectively prevents the intrusion of pollutants and moisture, thereby forming a preliminary protection for the contact plate to reduce the possibility of material deterioration when it contacts the outside world. At the same time, the axial setting of the anti-slip plate and the interference fit with the flange provide additional fixing strength to prevent the sealing cover from shifting or falling off during the operation of the bearing. The design of the clamping part and the slot further ensures the fixing stability 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; Figure 2 This is a partial enlarged view of the sealing component of Example 1 of the present invention; Figure 3 This is a partial enlarged view of the clamping post of Example 1 of the present invention; Figure 4 This is a partial enlarged view of the flow-blocking space in Example 1 of the present invention; Figure 5 This is a partial enlarged view of the anti-slip plate of Example 1 of the present invention; Figure 6 This is a partial enlarged view of the sealing convex point of Example 1 of the present invention; 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; Figure 8 It is a partial enlarged view of the flow-blocking space in Example 2 of the present invention.

[0027] 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 part; 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

[0028] Embodiment 1 of the present invention is a sealing structure of a hub bearing as shown in Figure 1-7 As shown: it includes a flange 1, a flange outer ring 2 and a sealing assembly 3, wherein 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.

[0029] The sealing cover 31 includes a sealing cover frame 311 made of SUS430 and a sealing component 312 made of NBR arranged on the sealing cover frame 311. The sealing cover frame 311 includes a contact plate 3111 and an anti-slip plate 3112, and the sealing component 312 includes a sealing convex point 3121 and a sealing retaining ring 3122, and the sealing retaining ring 3122, the sealing convex point 3121, the contact plate 3111 and the anti-slip plate 3112 are distributed on the sealing cover 31 from top to bottom along the radial direction.

[0030] 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, which are respectively arranged on the sealing ring frame 321, and the water-blocking lip 322, the water-blocking lip 323 and the sealing lip 324 are distributed from top to bottom along the radial direction on the sealing ring 32. A flow-blocking space 33 is formed between the water-blocking lip 323 and the water-blocking lip 322 to prevent the intrusion of external fluid.

[0031] The present embodiment is described below from the top to the bottom along the radial direction of the sealing component 3: A flow channel 334 leading from the outside to the flow blocking space 33 is formed between the sealing baffle ring 3122 and the water blocking lip 322. The end surface of one side of the flow channel 334 formed by the water blocking lip 322 is inclined, and the inclined setting makes the cross-sectional width of the flow channel 334 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 is provided with a plurality of reflow grooves 333 on the side close to the sealing ring 32. The sizes of the various parts of the flow blocking space 33 are as follows: Figure 7 As shown, the cross-sectional width of the flow channel 334 (i.e. 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 7B and C) are 0.4-1.0mm. The sealing ring 32 is located between the water retaining lip 322 and the water blocking lip 323 in the radial direction, and a U-shaped clamping groove 325 with its opening facing the axial direction is formed. A clamping column 21 is arranged on the flange outer ring 2 corresponding to the clamping groove 325. The two end faces of the clamping groove 325 and the clamping column 21 in radial contact are the sealing ring skeleton 321 and the water retaining lip 322, respectively. A plurality of contact convex points 3221 are arranged on the water retaining lip 322, and each contact convex point 3221 forms an interference fit with the clamping column 21, so that an interference fit is formed between the water retaining lip 322 and the clamping column 21. On the other side of the clamping groove 325, the sealing ring skeleton 321 also forms an interference fit with the clamping column 21. The end of the flow blocking space 33 located within the sealing cover 31 and the sealing ring 32 is a water blocking lip 323, which is inclined toward the axial direction away from the flange outer ring 2, and a water blocking protrusion 3231 extending in the radial direction is provided at the end of the water blocking lip 323 away from the sealing ring 32. The sealing ring 32 is provided with a sealing lip 324 radially below the water blocking lip 323, and the sealing lip 324 forms a sealing contact with the contact plate 3111 which is also inclined and not in contact with the flange 1, and after the sealing lip 324 forms a sealing contact with the contact plate 3111, the sealing lip 324 is inclined toward the axial direction away from the flange outer ring 2.

[0032] 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 inclined 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 clamping groove 11 is provided on the flange 1 to cooperate with the clamping portion 3113 to form a clamping fixation.

[0033] 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 the operation; in addition, the flow-blocking space 33 can prevent the external fluid from affecting the sealing lip 324 during the operation, thereby providing a good working environment for the sealing lip 324.

[0034] Embodiment 2 of the present invention is a sealing structure of a hub bearing, which is different from Embodiment 1 as follows: Figure 8As shown in the figure, a plurality of protrusions 3114 are arranged on the sealing cover frame 311 along the circumferential direction, each of the protrusions 3114 can contact the water blocking lip 323, and the contact point between the protrusions 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. A plurality of reflow grooves 333 arranged on one side of the second flow blocking area 332 are arranged with a flat surface 3331 on the side close to the water blocking lip 323, and an arc surface 3332 is formed opposite to the flat surface 3331.

[0035] During use of this embodiment, the sealing cover 31 rotates relative to the sealing ring 32, and 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, so as to bounce the external fluid that reaches there by centrifugal force into the reflux groove 333. As an optimization method, a reflux groove 333 closest to the water blocking lip 323 can be set in the direction of the torque generated after the protruding point 3114 contacts the water blocking lip 323. When the external fluid reaches the reflux groove 333, the arc surface 3332 away from the side of the water blocking lip 323 has the function of collecting the external fluid, and as the protruding point 3114 contacts the water blocking lip 323 to transmit the vibration generated by the contact to the reflux groove 333, the flat surface 3331 will vibrate, and the fluid in the reflux groove 333 will be thrown out into the reflux groove 333 further away from the water blocking lip, so as to circulate and keep the external fluid away from the second flow blocking area 332.

[0036] The above embodiment is only one of the preferred specific embodiments 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 facing the sealing cover to form a sealing contact therewith, the outer ring of the flange is provided with a clamping column, and the sealing ring is provided with a U-shaped clamping groove with its opening facing the axial direction corresponding to the clamping column, and the clamping groove cooperates with the clamping column to prevent the sealing ring from axial and radial displacement during the operation of the wheel hub bearing.

2. A wheel hub bearing sealing structure according to claim 1, characterized in that: The sealing ring comprises a frame and a water retaining lip arranged 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 respectively form an interference fit with the clamping column.

3. A wheel hub bearing sealing structure according to claim 2, 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.

4. A wheel hub bearing sealing structure according to claim 2, 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.

5. A wheel hub bearing sealing structure according to claim 4, 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.

6. A wheel hub bearing sealing structure according to claim 4, 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.

7. A wheel hub bearing sealing structure according to claim 6, 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.

8. The sealing structure of a hub bearing according to claim 1, characterized in that: The sealing cover is provided with a contact plate which is not in 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 flange outer ring.

9. A wheel hub bearing sealing structure according to claim 8, characterized in that: The contact plate and the sealing lip are both arranged at an inclination. 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.

10. The sealing structure of a hub bearing according to claim 8, characterized in that: 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 groove is provided on the flange to cooperate with the clamping portion to form a clamping fixation.

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