Maintenance-free hub bearing

Abstract

The utility model discloses a kind of maintenance-free hub bearings, including outer flange, inner race, shaft sleeve and double-row rolling body, first rolling groove is set on the outer peripheral wall of inner race and the outer peripheral wall of shaft sleeve, second rolling groove is set on the inner peripheral wall of outer flange corresponding two first rolling groove positions, each first rolling groove is combined with corresponding second rolling groove to form raceway, outer flange and shaft sleeve form rolling cavity and the both ends of rolling cavity are provided with sealing element, circumferential boss is integrally integrated on the outer peripheral wall of shaft sleeve, the first rolling groove of shaft sleeve is set on circumferential boss, the outer peripheral wall of shaft sleeve initial end is provided with the adjusting structure for axially driving inner race to move relative to circumferential boss to accurately adjust bearing play and lock fixedly to inner race, the outer peripheral wall of shaft sleeve terminal end is provided with the connecting structure for making shaft sleeve and external bridge seat detachably connected.The utility model solves the problem that the existing maintenance-free hub bearing adopts double inner race structure, leading to big play adjustment dispersion, poor consistency, and assembly relies on welding, inconvenient maintenance.

Description

Technical Field

[0001] This utility model relates to the field of bearing technology, specifically to a maintenance-free wheel hub bearing. Background Technology

[0002] Maintenance-free wheel bearings are critical load-bearing components in vehicle chassis systems. Their clearance accuracy, sealing reliability, and ease of assembly and maintenance directly affect the overall vehicle's operational stability and service life. Currently, most maintenance-free wheel bearings employ a double inner ring structure. During actual assembly, the axial position of the two independent inner rings must be adjusted simultaneously by tightening lock nuts to control the bearing clearance. However, since both inner rings are adjustable, variations in manufacturing tolerances, tooling precision, and manual operation can easily lead to large dispersion and poor consistency in clearance adjustment, potentially causing premature overheating, spalling, or failure of the bearing, making it difficult to guarantee reliability. Furthermore, existing wheel bearings often use welding to fix the bushing and bearing housing. This not only makes assembly precision difficult to control but also results in a non-removable connection. Once the bearing fails, the overall replacement cost is high, and maintenance is difficult. Utility Model Content

[0003] To address the shortcomings of existing technologies, this utility model provides a maintenance-free wheel hub bearing. This addresses the problems of large dispersion and poor consistency in clearance adjustment caused by the double inner ring structure of existing maintenance-free wheel hub bearings, as well as the inconvenience of assembly due to welding.

[0004] To achieve the above objectives, this utility model provides a maintenance-free hub bearing, comprising an outer flange, an inner ring, a bushing, and double-row rolling elements. First grooves are formed on the outer peripheral walls of both the inner ring and the bushing. Second grooves are formed on the inner peripheral wall of the outer flange corresponding to the two first grooves. Each first groove combines with its corresponding second groove to form a raceway for the single-row rolling elements. A rolling cavity is formed between the outer flange and the bushing, with seals at both ends of the cavity. A circumferential boss is integrally integrated on the outer peripheral wall of the bushing. The first groove of the bushing is formed on the circumferential boss. An adjustment structure is provided on the outer peripheral wall at the beginning of the bushing for axially driving the inner ring to move relative to the circumferential boss to precisely adjust the bearing clearance and lock the inner ring in place. A connection structure is provided on the outer peripheral wall at the end of the bushing for detachably connecting the bushing to an external bridge seat.

[0005] The advantages of adopting the above technical solution are as follows: The technology utilizes the combination of an outer flange, inner ring, bushing, and double-row rolling elements. The bushing's outer circumferential wall is integrally integrated with a circumferential boss and has a first rolling groove, replacing the traditional double inner ring structure. This reduces clearance adjustment variables, lowers clearance adjustment dispersion, and improves clearance consistency. A rolling cavity is formed between the outer flange and bushing, with seals at both ends, creating a basic sealing barrier to prevent external impurities from entering the rolling cavity. An adjustment structure at the beginning of the bushing allows for axial movement of the inner ring relative to the circumferential boss, precisely adjusting and locking the bearing clearance, avoiding errors from manual adjustment. The connecting structure at the end of the bushing enables a detachable connection between the bushing and the bearing housing. Compared to traditional welding assembly methods, this structure improves assembly accuracy, simplifies disassembly and assembly processes, and reduces maintenance costs, thereby enhancing the overall reliability and adaptability of the bearing.

[0006] The present invention further includes the following features: the adjustment structure includes a locking nut sleeved on the outer peripheral wall of the beginning end of the bushing, the locking nut being threadedly connected to the outer peripheral wall of the bushing, the left side wall of the inner ring being abutted against the bottom wall of the locking nut, and the right side wall of the inner ring being abutted against the left side wall of the circumferential boss.

[0007] The advantages of adopting the above technical solution are as follows: The adjustment structure in the above technology adopts a locking nut and a threaded connection with the bushing, which is simple, compact and easy to assemble; the locking nut abuts against the left side wall of the inner ring and the right side wall of the inner ring abuts against the left side wall of the circumferential boss, forming a one-way adjustment and limiting structure. By rotating the locking nut, the relatively fixed circumferential boss of the inner ring can be moved axially. Only the position of a single inner ring needs to be adjusted, thereby reducing the adjustment steps, accurately controlling the bearing clearance, avoiding the superposition of errors when adjusting two inner rings, and ensuring the consistency of clearance. Moreover, the threaded connection has a self-locking performance, which can stably lock the position of the inner ring, prevent the axial movement of the inner ring during use, maintain the stability of the clearance, reduce the risk of early bearing failure, and improve operational reliability.

[0008] The present invention further comprises: the connecting structure including a connecting ring circumferentially formed on the outer peripheral wall of the end of the bushing; the connecting ring having a plurality of connecting bolts for threaded engagement with pre-embedded holes on the external bridge seat; the ends of the connecting bolts being threadedly connected to connecting nuts; the bottom wall of the connecting nut abutting against the inner wall of the connecting ring; the inner wall of the connecting ring being near the sealing element on the right side of the outer flange and having a clearance fit to form a sealing gap; the connecting nut being located in the sealing gap; and the top wall of the connecting nut having a clearance fit with the adjacent sealing element and combining with the sealing gap to form a first labyrinth groove.

[0009] The advantages of adopting the above technical solution are as follows: The connection structure in the above technology uses a connecting ring in conjunction with connecting bolts and connecting nuts to achieve a detachable rigid connection between the bushing and the bridge seat, replacing the traditional welding fixation. This avoids welding deformation affecting assembly accuracy, facilitates individual disassembly and replacement in case of bearing failure, and reduces maintenance costs. The inner wall of the connecting ring and the seal form a sealing gap, and the connecting nut is placed in the sealing gap. The top wall of the connecting nut and the seal form a first labyrinth groove. This labyrinth structure can provide multiple barriers against external mud, water, and dust, slowing down the rate of impurity intrusion, enhancing the sealing performance of the bearing end, and thus preventing impurities from seeping into the rolling cavity through the connection part, protecting the internal rolling elements and raceways, thereby extending the service life of the bearing.

[0010] The present invention further comprises: the sealing element consisting of an outer skeleton and an inner skeleton, both of which are covered with a rubber layer; the inner skeleton is connected to the inner peripheral wall of the outer flange; the two outer skeletons are respectively connected to the outer peripheral wall of the inner ring and the outer peripheral wall of the flange boss; the rubber layer on the inner skeleton extends integrally toward the outer skeleton and has a first sealing lip for interference fit with the inner wall of the outer skeleton; the rubber pads on the two inner skeletons extend toward the outer peripheral wall of the inner ring and the outer peripheral wall of the circumferential boss respectively and have a second sealing lip for interference fit; the inner skeleton, outer skeleton, first sealing lip and second sealing lip combine to form a second labyrinth groove.

[0011] The advantages of adopting the above technical solution are as follows: The sealing component in the above technology adopts a composite structure of an outer skeleton and an inner skeleton covered with a rubber layer. The outer skeleton and the inner skeleton provide rigid support, enhancing the structural strength and installation stability of the sealing component and preventing deformation and detachment during use. The inner skeleton is connected to the outer flange, and the outer skeleton is connected to the inner ring and the circumferential boss respectively, realizing the tight assembly of the sealing component and the various components of the bearing. The first sealing lip is interference-fitted with the inner wall of the outer skeleton to form a radial seal, blocking external impurities. The second sealing lip is interference-fitted with the outer peripheral wall of the inner ring and the circumferential boss respectively, thereby enhancing the axial sealing effect. The combination of the inner skeleton, outer skeleton, first sealing lip and second sealing lip forms a second labyrinth groove, which further blocks the intrusion of impurities through the labyrinth effect, improves the sealing reliability, reduces the leakage and deterioration of grease inside the rolling cavity, and thus ensures long-term lubrication of the bearing.

[0012] The present invention further comprises: a sealing groove is provided circumferentially on the inner peripheral wall of the inner ring, a sealing ring is provided in the sealing groove, and the inner peripheral wall of the shaft hole of the sealing ring is configured to be interference fit with the outer peripheral wall of the bushing.

[0013] The advantages of adopting the above technical solution are: in the above technology, a sealing groove is opened on the inner circumferential wall of the inner ring and a sealing ring is set. Through the interference fit between the sealing ring and the outer circumferential wall of the bushing, a radial sealing structure is formed between the inner ring and the bushing, which can effectively prevent external impurities from entering the rolling cavity through the fit gap between the inner ring and the bushing.

[0014] The present invention further comprises: a central oil seal provided between the inner ring and the circumferential boss to prevent external impurities from entering the rolling cavity through the gap between the inner ring and the circumferential boss; the central oil seal is composed of a main sealing ring in the shape of an annular shape and a secondary sealing ring in the shape of an annular shape; the secondary sealing ring is located at the connection between the inner ring and the circumferential boss and is partially interference-fitted with the inner ring and the circumferential boss respectively; the main sealing ring is sleeved on the secondary sealing ring; and the radial cross section of the main sealing ring is arranged in an "L" shape.

[0015] The advantages of adopting the above technical solution are as follows: A central oil seal is installed between the inner ring and the circumferential boss, which can precisely prevent external impurities from entering the rolling cavity through the connection gap between the inner ring and the circumferential boss, filling the sealing gap of the end seal and thus improving the internal sealing protection of the bearing. The central oil seal consists of a main sealing ring and a secondary sealing ring. The secondary sealing ring is located at the connection between the inner ring and the circumferential boss and has a partial interference fit, achieving basic sealing at the gap and preventing direct penetration of impurities. The main sealing ring is fitted onto the secondary sealing ring and has an L-shaped radial cross-section, forming a double sealing barrier in both the axial and radial directions, enhancing resistance to impurity impacts and limiting the leakage of internal grease to avoid lubrication failure. This double sealing ring combination structure improves sealing stability, adapting to minute displacements during bearing operation and ensuring long-term sealing effectiveness. Attached Figure Description

[0016] Figure 1 This is a partial sectional view of the present invention; Figure 2 This is a partial enlarged view of part A in this utility model; Figure 3 This is a partial enlarged view of part B in this utility model. Detailed Implementation

[0017] This utility model provides a maintenance-free wheel hub bearing, including an outer flange 1, an inner ring 2, a bushing 3, and double-row rolling elements 11. First grooves 21 are formed on the outer peripheral walls of the inner ring 2 and the bushing 3. Second grooves 12 are formed on the inner peripheral wall of the outer flange 1 corresponding to the two first grooves 21. Each first groove 21 combines with its corresponding second groove 12 to form a raceway 22 for the single-row rolling elements 11 to roll. A rolling cavity is formed between the outer flange 1 and the bushing 3, and seals are provided at both ends of the rolling cavity. A circumferential boss 31 is integrally integrated on the outer peripheral wall of the bushing 3. The first grooves 21 of the bushing 3 are formed on the circumferential boss 31. A circumferential boss for axially driving the inner ring 2 relative to the circumferential boss is provided on the outer peripheral wall of the beginning end of the bushing 3. The bushing 31 is a movable adjustment structure for precisely adjusting bearing clearance and locking the inner ring 2. The outer peripheral wall of the bushing 3 has a connecting structure for detachably connecting the bushing 3 to the external bridge seat. The adjustment structure includes a locking nut 32 fitted onto the outer peripheral wall of the bushing 3. The locking nut 32 is threadedly connected to the outer peripheral wall of the bushing 3. The left side wall of the inner ring 2 abuts against the bottom wall of the locking nut 32, and the right side wall of the inner ring 2 abuts against the left side wall of the circumferential boss 31. The connecting structure includes a connecting ring 33 circumferentially formed on the outer peripheral wall of the bushing 3. The connecting ring 33 has several connecting bolts 331 threadedly engaged with pre-embedded holes on the external bridge seat. The ends of the connecting bolts 331 are threaded... A connecting nut 332 is connected to the outer flange 1. The bottom wall of the connecting nut 332 abuts against the inner wall of the connecting ring 33. The inner wall of the connecting ring 33 is close to the sealing element on the right side of the outer flange 1 and forms a sealing gap with a clearance fit. The connecting nut 332 is located in the sealing gap. The top wall of the connecting nut 332 is in clearance fit with the adjacent sealing element and, together with the sealing gap, forms a first labyrinth groove 34. The sealing element is composed of an outer skeleton 4 and an inner skeleton 41. Both the outer skeleton 4 and the inner skeleton 41 are covered with a rubber layer 42. The inner skeleton 41 is connected to the inner peripheral wall of the outer flange 1. The two outer skeletons 4 are respectively connected to the outer peripheral wall of the inner ring 2 and the outer peripheral wall of the flange boss. The rubber layer 42 on the inner skeleton 41 faces the outer skeleton 4. The inner ring 41 has a first sealing lip 411 that extends integrally to form an interference fit with the inner wall of the outer frame 4. Rubber pads on the two inner frames 41 extend towards the outer peripheral wall of the inner ring 2 and the outer peripheral wall of the circumferential boss 31, respectively, and are interference-fitted with a second sealing lip 412. The inner frame 41, outer frame 4, first sealing lip 411, and second sealing lip 412 combine to form a second labyrinth groove 43. A sealing groove 22 is circumferentially formed on the inner peripheral wall of the inner ring 2, and a sealing ring 23 is disposed in the sealing groove 22. The inner peripheral wall of the shaft hole of the sealing ring 23 is interference-fitted with the outer peripheral wall of the bushing 3. A central oil seal 24 is disposed between the inner ring 2 and the circumferential boss 31 to prevent external impurities from entering the rolling cavity through the gap between the inner ring 2 and the circumferential boss 31.The central oil seal 24 consists of a main sealing ring 241 and a secondary sealing ring 242, both in annular shape. The secondary sealing ring 242 is located at the connection between the inner ring 2 and the circumferential boss 31, and is partially press-fitted with both the inner ring 2 and the circumferential boss 31. The main sealing ring 241 is fitted onto the secondary sealing ring 242, and its radial cross-section is L-shaped.

[0018] The bridge pedestal described above is designated as 5 in the accompanying drawings of the specification.

[0019] The foregoing has shown and described the basic principles and main features of this utility model, as well as its advantages. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications may be made to this utility model without departing from its spirit and scope. All such changes and modifications fall within the scope of protection of this utility model as defined by the appended claims and their equivalents.

Claims

1. A maintenance-free hub bearing, comprising an outer flange, an inner ring, a bushing, and double-row rolling elements, characterized in that: The outer peripheral wall of the inner ring and the outer peripheral wall of the bushing are both provided with first grooves. The inner peripheral wall of the outer flange is provided with second grooves corresponding to the two first grooves. Each first groove and its corresponding second groove are combined to form a raceway for a single row of rolling elements to roll. A rolling cavity is formed between the outer flange and the bushing, and a seal is provided at both ends of the rolling cavity. A circumferential boss is integrally integrated on the outer peripheral wall of the bushing. The first groove of the bushing is opened on the circumferential boss. An adjustment structure is provided on the outer peripheral wall at the beginning of the bushing for axially driving the inner ring to move relative to the circumferential boss to accurately adjust the bearing clearance and lock the inner ring. A connection structure is provided on the outer peripheral wall at the end of the bushing for detachably connecting the bushing to the external bridge seat.

2. The maintenance-free hub bearing according to claim 1, characterized in that: The adjustment structure includes a locking nut sleeved on the outer peripheral wall of the beginning end of the bushing. The locking nut is threadedly connected to the outer peripheral wall of the bushing. The left side wall of the inner ring abuts against the bottom wall of the locking nut. The right side wall of the inner ring abuts against the left side wall of the circumferential boss.

3. The maintenance-free hub bearing according to claim 1, characterized in that: The connection structure includes a connecting ring circumferentially formed on the outer peripheral wall of the end of the bushing. The connecting ring is provided with a plurality of connecting bolts for threaded engagement with pre-embedded holes on the external bridge seat. The ends of the connecting bolts are threaded with connecting nuts. The bottom wall of the connecting nut abuts against the inner wall of the connecting ring. The inner wall of the connecting ring is close to the sealing element on the right side of the outer flange and forms a sealing gap with clearance. The connecting nut is located in the sealing gap. The top wall of the connecting nut has a clearance fit with the adjacent sealing element and, together with the sealing gap, forms a first labyrinth groove.

4. The maintenance-free hub bearing according to claim 1, characterized in that: The sealing element consists of an outer skeleton and an inner skeleton, both of which are covered with a rubber layer. The inner skeleton is connected to the inner peripheral wall of the outer flange. The two outer skeletons are respectively connected to the outer peripheral wall of the inner ring and the outer peripheral wall of the flange boss. The rubber layer on the inner skeleton extends integrally towards the outer skeleton and has a first sealing lip for interference fit with the inner wall of the outer skeleton. The rubber gaskets on the two inner skeletons extend towards the outer peripheral wall of the inner ring and the outer peripheral wall of the flange boss respectively and have a second sealing lip for interference fit. The inner skeleton, outer skeleton, first sealing lip and second sealing lip combine to form a second labyrinth groove.

5. A maintenance-free hub bearing according to claim 1, characterized in that: A sealing groove is provided circumferentially on the inner peripheral wall of the inner ring, and a sealing ring is provided in the sealing groove. The inner peripheral wall of the shaft hole of the sealing ring is interference-fitted with the outer peripheral wall of the bushing.

6. The maintenance-free hub bearing according to claim 1, characterized in that: A central oil seal is provided between the inner ring and the circumferential boss to prevent external impurities from entering the rolling cavity through the gap between the inner ring and the circumferential boss. The central oil seal consists of a main sealing ring and a secondary sealing ring in an annular shape. The secondary sealing ring is located at the connection between the inner ring and the circumferential boss and is partially interference-fitted with both the inner ring and the circumferential boss. The main sealing ring is sleeved on the secondary sealing ring, and the radial cross-section of the main sealing ring is L-shaped.

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