Maintenance-free hub step bearing of drive axle

Abstract

The utility model relates to a maintenance-free hub step bearing of a drive axle, which comprises a large outer bearing and a small inner bearing which are connected to form a step bearing with a small end and a large end. The outer bearing comprises an outer bearing outer ring and an outer bearing inner ring, the inner bearing comprises an inner bearing outer ring and an inner bearing inner ring, and the outer bearing inner ring and the inner bearing inner ring are connected through a fixing ring. The inner bearing is larger in specification, thereby improving dynamic load and service life of the bearing. The hub unit adopts a maintenance-free structure, and is simple to assemble and convenient to operate. The step bearing unit with the maintenance-free hub is suitable for commercial tractors and trucks, and can be realized without damaging the original chassis arrangement of the whole truck.

Description

Technical Field

[0001] This utility model relates to a bearing, and more particularly to a maintenance-free stepped bearing for a drive axle hub. Background Technology

[0002] Currently, to achieve long-term maintenance or even maintenance-free operation, the rear drive axles of commercial tractors generally use grease-lubricated, maintenance-free bearing units in the wheel hubs. However, due to structural and functional limitations, existing grease-lubricated wheel hub bearing units often use the same size and model for both the inner and outer bearings, without differentiation in terms of strength. Given the complex and variable operating conditions of vehicles in China, this bearing unit structure carries the risk of reduced reliability and maintenance mileage.

[0003] High reliability and maintenance-free operation are the themes of future development for commercial tractor vehicles. The rear drive axle hub unit plays a supporting and load-bearing role in the whole vehicle and drives the wheels to rotate. It is in the most severe environment in the commercial vehicle operating chassis. Only with higher reliability can we achieve the goal of "less maintenance, less station visits, and more operation" and reduce the total cost of ownership (TCO) of the whole vehicle operation for customers. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide a maintenance-free stepped bearing for drive axles, which achieves high stability and high reliability, based on the shortcomings of the existing technology.

[0005] The technical solution to the above technical problem is: a maintenance-free stepped bearing for a drive axle hub, comprising an outer bearing of one large size and an inner bearing of one small size, wherein the outer bearing and the inner bearing are connected to form a stepped bearing with one small end and one large end.

[0006] A further technical solution of this utility model is as follows: the outer bearing includes an outer bearing outer ring and an outer bearing inner ring, and the inner bearing includes an inner bearing outer ring and an inner bearing inner ring. The outer bearing inner ring and the inner bearing inner ring are connected by a retaining ring. An intermediate sealing ring is provided at the connection between the outer bearing and the inner bearing. An O-ring is provided at the assembly point of the inner bearing and the shaft tube.

[0007] The stepped bearing is equipped with an oil seal. The outer bearing has an outer oil seal on its inner ring, and the inner bearing has an inner oil seal on its inner ring.

[0008] Due to the adoption of the above technical solution, the maintenance-free wheel hub stepped bearing of this utility model has the following beneficial effects:

[0009] 1. This utility model adopts a stepped bearing unit structure. When the drive axle bears the entire vehicle load, the inner bearing accounts for more than 60% of the force. The inner bearing uses a larger specification to improve dynamic load and bearing life. The wheel hub unit of this utility model adopts a maintenance-free structure, is simple to assemble, and easy to operate. This maintenance-free stepped bearing unit for wheel hubs is suitable for commercial tractor trucks and cargo trucks, and can be implemented without damaging the original vehicle chassis layout.

[0010] 2. This utility model features strong versatility, simple structure, convenient manufacturing, high reliability, and long service life, which can greatly reduce the number of times users need to visit the maintenance station, thereby achieving the goal of reducing operating costs and improving user experience. The rounded corners of the bearing inside the shaft tube of this utility model can be thickened for optimization, further improving reliability and service life.

[0011] The technical features of a maintenance-free wheel hub stepped bearing for a drive axle of this utility model will be further described below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0012] Figure 1 : A schematic diagram of a maintenance-free wheel hub stepped bearing for a drive axle.

[0013] Figure 2 : A schematic diagram of the installation state of a maintenance-free wheel hub stepped bearing for a drive axle.

[0014] In the above figures, the reference numerals are explained as follows:

[0015] 1-Outer bearing, 2-Inner bearing, 3-Outer oil seal, 4-Outer bearing outer ring, 5-Outer bearing inner ring, 6-Inner bearing outer ring, 7-Inner bearing inner ring, 8-Inner oil seal, 9-O-ring seal, 10-Intermediate seal, 11-Retaining ring, 12-Wheel hub, 13-Shaft tube, 14-Anti-friction washer, 15-Locking nut, 16-Wheel bolt, 17-Drive axle half-shaft, 18-Bolt. Detailed Implementation

[0016] A maintenance-free stepped bearing for a drive axle hub includes an outer bearing 1 (larger than the inner bearing 2) and an inner bearing 2 (lower than the outer bearing 1). The outer and inner bearings are connected to form a stepped bearing with one end smaller than the other. The outer bearing includes an outer ring 4 and an inner ring 5, and the inner bearing includes an outer ring 6 and an inner ring 7. The inner rings 5 ​​and 7 are connected by a retaining ring, and an intermediate sealing ring is provided at the connection between the outer and inner bearings. An O-ring is provided at the assembly point of the inner bearing and the shaft tube. In the outer and inner bearings, the diameter of the outer bearing is smaller than that of the inner bearing. The larger diameter of the inner bearing results in a larger cross-sectional area, and under the same load conditions, it has higher strength, greater dynamic load, and a longer service life compared to a bearing with a smaller inner diameter.

[0017] Specifically, the bearing unit includes an outer oil seal 3, an outer bearing outer ring 4, an outer bearing inner ring 5, an inner bearing outer ring 6, an inner bearing inner ring 7, an inner oil seal 8, an O-ring seal 9, an intermediate sealing ring 10, and a locating ring 11. The outer bearing outer ring 4 is mounted on the outer bearing inner ring 5 via ball bearings, and the inner bearing outer ring 6 is mounted on the inner bearing inner ring 7 via ball bearings. The outer bearing inner ring 5 and the inner bearing inner ring 7 are connected by a retaining ring and sealed with a sealing ring. The outer bearing inner ring 5 and the inner bearing inner ring 7 form a stepped bearing unit with a stepped structure that is smaller at one end and larger at the other. In the stepped bearing unit, the outer bearing is the smaller bearing, and the inner bearing is the larger bearing. Oil seals are added to both the outer bearing inner ring 5 and the inner bearing inner ring 7 for sealing; that is, the outer bearing inner ring 5 is equipped with an outer oil seal 3, and the inner bearing inner ring 7 is equipped with an inner oil seal 8. An O-ring seal is used at the assembly point of the inner bearing and the shaft tube to prevent lubricating oil from entering and contaminating the grease.

[0018] When assembling the stepped bearing unit, only the lock nut needs to be tightened; no adjustment of bearing clearance is required, making assembly simple and convenient. The outer ring of the stepped bearing unit is press-fitted onto the wheel hub 12 (i.e., the outer rings of the large and small bearings are press-fitted onto the wheel hub 12), and the inner ring of the stepped bearing unit is assembled onto the axle tube 13 (the inner rings of the large and small bearings are assembled onto the axle tube 13). Anti-friction shims 14 and lock nuts 15 are used for tightening. Wheel bolts 16 are press-fitted into the mounting holes of the wheel hub 12, and the drive axle half-shaft 17 is fixed to the wheel hub 12 by bolts 18. When the vehicle is working, the drive axle half-shaft is stressed, driving the wheel hub to rotate. The wheel hub then drives the tires via the wheel bolts. The stepped bearing reduces friction, improving operating efficiency. By using stepped inner and outer large and small bearings, complex operating conditions are addressed, improving overall vehicle reliability. Thickening and optimization of the axle tube fillet reduces the risk of breakage. The stepped bearing unit achieves high reliability, high maintenance-free operation, and high performance for the entire vehicle.

Claims

1. A drive axle maintenance-free hub step bearing characterized by: It comprises a big and small outer bearing and inner bearing, the outer bearing and inner bearing are connected to form a stepped bearing with one end small and one end big; the outer bearing comprises an outer bearing outer ring and an outer bearing inner ring, the inner bearing comprises an inner bearing outer ring and an inner bearing inner ring, the outer bearing inner ring and the inner bearing inner ring are connected through a fixed ring; an intermediate sealing ring is arranged at the connecting position of the outer bearing and the inner bearing.

2. A maintenance-free hub step bearing for a drive axle as set forth in claim 1, characterized in that: An O-shaped sealing ring is arranged at the assembling position of the inner bearing and the shaft tube.

3. A maintenance-free hub step bearing for a drive axle as set forth in claim 1, characterized in that: An oil seal is arranged on the stepped bearing.

4. A maintenance-free hub step bearing for a drive axle as set forth in claim 3 wherein: An outer oil seal is arranged on the outer bearing inner ring, and an inner oil seal is arranged on the inner bearing inner ring.

Images