CN110576736A

CN110576736A - Wheel hub drive arrangement and vehicle

Info

Publication number: CN110576736A
Application number: CN201810594521.2A
Authority: CN
Inventors: 王荣偲; 钟泽成
Original assignee: Schaeffler Technologies AG and Co KG
Current assignee: Schaeffler Technologies AG and Co KG
Priority date: 2018-06-11
Filing date: 2018-06-11
Publication date: 2019-12-17

Abstract

The invention discloses a wheel hub driving device for a vehicle and the vehicle, the wheel hub driving device comprises: the electric motor comprises a motor, a speed reducer, a flange shaft and a hub, wherein the motor drives the flange shaft through the speed reducer, the flange shaft is connected with the hub in a torque-proof mode, the flange shaft is composed of a flange plate used for being connected with the hub and a supporting shaft used for supporting the speed reducer, a sealing device is arranged in a radial space between the flange plate and a motor shell of the motor, a gap is reserved in an axial space between the flange plate and the motor shell, and a thrust ball bearing is arranged in the gap in order to avoid inclination of the flange shaft when the vehicle runs.

Description

Wheel hub drive arrangement and vehicle

Technical Field

The invention relates to a wheel hub drive for a vehicle, comprising: the motor comprises a motor, a speed reducer, a flange shaft and a hub, wherein the motor drives the flange shaft through the speed reducer, the flange shaft is connected with the hub in a torque-proof manner, the flange shaft is composed of a flange plate used for being connected with the hub and a supporting shaft used for supporting the speed reducer and a motor shell of the motor by means of a hub bearing, a sealing device is arranged in a radial space between the flange plate and the motor shell, and a gap is reserved in an axial space between the flange plate and the motor shell.

Background

New energy automobiles become a main direction of future development of the automobile industry, the driving technology of new energy automobiles is greatly different from the driving technology of internal combustion engine automobiles, and one type of driving technology has good development prospect, namely the hub motor technology. The wheel hub motor technology is also called as the wheel built-in motor technology, and the most important characteristic is that the power, transmission and braking devices are integrated into the contour, so that the mechanical part of the electric vehicle is greatly simplified.

A hub drive is known from CN 105691185 a. Such a wheel hub driving apparatus includes a motor, a housing for holding the motor, a flange shaft for driving a wheel to rotate, and a sealing device for preventing foreign materials from entering and internal lubricating oil from leaking. Since the flange shaft is connected to the wheel via the hub and a gap may exist between the flange shaft and the housing, during driving, particularly when cornering, the flange shaft may deflect due to changes in load, which may cause the sealing device to fail, thereby affecting the operation of the internal electric motor.

Disclosure of Invention

The present invention is therefore based on the object of providing an improved hub drive which makes it possible to avoid a severe tilting of the flange shaft under operating load.

The technical problem is solved by a hub drive for a vehicle, comprising: the motor comprises a motor, a speed reducer, a flange shaft and a hub, wherein the motor drives the flange shaft through the speed reducer, the flange shaft is connected with the hub in a torque-proof mode, the flange shaft is composed of a flange plate used for being connected with the hub and a supporting shaft used for supporting the speed reducer, a sealing device is arranged in a radial space between the flange plate and a motor shell of the motor, and a gap is reserved in an axial space between the flange plate and the motor shell. In order to avoid tilting of the flange shaft during driving of the vehicle, a thrust ball bearing is arranged in the recess. Since the thrust ball bearing is supported between the flange of the flange shaft and the stationary motor housing, tilting of the flange is prevented. Preferably, the outer ring of the thrust ball bearing is attached to the flange plate, and the inner ring of the thrust ball bearing is attached to the motor shell, so that the thrust ball bearing occupies the axial space between the flange plate and the motor shell, collision between the flange plate and the thrust ball bearing when the flange plate inclines is avoided, and the NVH performance of a vehicle is improved. It is further preferred that the thrust ball bearing is fitted with radial play on the bearing shaft and is clamped by the flange and the motor housing, so that the thrust ball bearing is fitted between the flange and the motor housing in a very simple manner.

According to a preferred embodiment of the invention, the thrust ball bearing provided in the axial space between the flange and the motor housing is a one-way thrust ball bearing. Since the flange plate is inclined when the vehicle turns, namely, one direction of the thrust ball bearing receives axial force, only the one-way thrust ball bearing can be arranged to reduce the cost of components. Advantageously, the single-direction thrust ball bearing has a collar which bears against the flange and a raceway which bears against the motor housing in order to counteract axial forces from the flange. Preferably, the race of the thrust ball bearing is designed as a self-aligning race, so that a self-aligning washer is also required between this race and the motor. The self-aligning seat ring is combined with the self-aligning gasket to eliminate the centering error of the thrust ball bearing. Of course, a bidirectional thrust ball bearing is also contemplated.

According to a further preferred embodiment of the invention, the flange is provided with a concentric annular projection on the end face on the side facing away from the bearing axis, wherein the sealing means rests on the projection. The outer diameter of the boss is slightly smaller than that of the flange plate, so that one end of the sealing device abuts against the boss, and the other end of the sealing device abuts against the flange plate, and therefore the sealing device can be better held and is prevented from losing efficacy in the vehicle running process. Advantageously, oil-conducting openings are provided in the flange for conducting the lubricating oil flowing into the sealing arrangement back to the interior of the hub drive. When the hub driving device works, because the flange shaft is always in a rotating state, a certain amount of lubricating oil is accumulated at the sealing device under the action of centrifugal force. The lubricating oil can be reintroduced to the supporting shaft by utilizing the oil guide hole, so that the lubricating effect of the rotating part is increased, and the lubricating oil is prevented from flowing out to the external environment through the sealing device.

The object is also achieved by a vehicle having a wheel hub drive according to the above-mentioned features.

Drawings

The features of the present invention will be described in detail below with reference to preferred embodiments thereof. The attached drawings are as follows:

Fig. 1 shows a cross-sectional view of a hub drive according to the prior art;

FIG. 2 shows a perspective view of a flanged shaft according to the present invention;

Fig. 3 shows a detail of the hub drive according to the invention.

identical or functionally similar elements are provided with the same reference signs.

Detailed Description

Fig. 1 shows a cross-sectional view of a hub drive according to the prior art. The hub driving device includes a hub (not shown in fig. 1) for supporting a tire of a vehicle, a flange shaft 1, a hub bearing 7 supporting the flange shaft 1, a speed reducer 2 (planetary gear mechanism), a motor 6, a motor housing 3 for holding the motor 6, and a sealing device 5. In the motor housing 3, a rotor of the motor is arranged, which rotates the flange shaft 1 by means of the reduction gear 2, and a hub bearing 7 is arranged between the flange shaft 1 and the motor housing 3. The flange shaft 1 is composed of a flange 8 and a support shaft 9 at the end, a plurality of mounting holes 4 are provided on the flange 8, the mounting holes 4 are uniformly distributed on the circumference of the flange 8, and the flange shaft 2 is fixedly connected with a hub through the mounting holes 4. The hub bearing 7 is supported on a support shaft 9 of the flange shaft 1. When the rotor of the motor 6 rotates the flange shaft 1 through the speed reducer 2 composed of the planetary gear, the flange shaft 1 drives the wheel hub to rotate.

A sealing device 5 is arranged radially between the flange shaft 1 and the motor housing 3, which sealing device is arranged close to the hub, so that external impurities can be prevented from entering the interior of the hub drive and, at the same time, the internal lubricating oil can be prevented from flowing out to the outside environment.

Fig. 2 shows a perspective view of a flange shaft according to the invention. The flange shaft 1 is composed of a shaft-like support shaft and a disk-like flange 8. A collar 10 with a slightly smaller radius is provided on the flange 8 in the direction facing away from the bearing axis. The boss 10 is used to house the sealing device 5, as shown in figure 3 below.

Fig. 3 shows a detail of the hub drive according to the invention, enlarged in the circled portion of fig. 1, in order to more clearly show the differences between the invention and the prior art. As shown in fig. 3, a projection 10 projecting toward the outside environment is provided on the flange 8, and the sealing device 5 rests on this projection 10. A thrust ball bearing 11 is arranged in the axial gap between the flange 8 and the motor housing 3. The thrust ball bearing 11 is, in particular, a one-way thrust ball bearing, having a shaft ring 12 and a raceway ring 13. The collar 12 is seated against the flange 8, while the seat 13 is seated against the motor housing 3. The race 13 is preferably a self-aligning race, in which case a self-aligning washer is also provided between the race 13 and the motor housing 3, which cooperates with the self-aligning race to eliminate alignment errors of the thrust ball bearings. Of course, it is also conceivable to use a bidirectional thrust ball bearing here. As shown in the drawing, an oil guide opening 14 is also provided in the flange 8 for guiding the lubricating oil in the sealing device 5 back into the interior space on the right side of the flange 8, wherein the oil guide opening 14 preferably opens into the gap between the thrust ball bearing 11 and the bearing shaft 9.

Although possible embodiments have been described by way of example in the above description, it should be understood that numerous embodiment variations exist, still by way of combination of all known and easily imaginable technical features and embodiments by the skilled person. It should also be appreciated that the exemplary embodiment or exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the invention in any way. From the foregoing description, one of ordinary skill in the art will more particularly provide a technical guide to convert at least one exemplary embodiment, wherein various changes may be made, particularly in matters of function and structure of the components described, without departing from the scope of the following claims.

List of reference numerals

1 Flange shaft

2 speed reducer

3 Motor casing

4 mounting hole

5 sealing device

6 electric machine

7 hub bearing

8 flange

9 supporting axle

10 boss

11 thrust ball bearing

12 axle ring

13 seat ring

14 oil guide hole

Claims

1. A hub drive device for a vehicle, comprising: -an electric machine (6), -a speed reducer (2), -a flange shaft (1) and a hub, wherein the electric machine drives the flange shaft (1) via the speed reducer (2), the flange shaft (1) being connected to the hub in a rotationally fixed manner, wherein the flange shaft (1) is formed by a flange (8) for connection to the hub and a bearing shaft (9) that supports the speed reducer (2), wherein a sealing device (5) is provided in a radial space between the flange (8) and a motor housing (3) of the electric machine (6), a recess being left in an axial space between the flange (8) and the motor housing (3), characterized in that a thrust ball bearing (10) is arranged in the recess.

2. The wheel hub drive according to claim 1, characterized in that the outer ring of the thrust ball bearing (10) bears against the flange (8) and the inner ring of the thrust ball bearing (10) bears against the motor housing (3).

3. The wheel hub drive according to claim 2, characterized in that the thrust ball bearing (10) is arranged with radial play on the bearing shaft (9) and is clamped by the flange (8) and the motor housing (3).

4. The hub drive of claim 1, wherein the thrust ball bearing is a one-way thrust ball bearing.

5. The wheel hub drive according to claim 4, characterized in that the thrust ball bearing has a collar (11) and a race (12), the collar (11) bearing against the flange (8) and the race (12) bearing against the motor housing (3).

6. Wheel hub drive according to claim 5, characterized in that the race (12) is designed as a self-aligning race.

7. The hub drive of claim 1, wherein the thrust ball bearing is a two-way thrust ball bearing.

8. The hub drive according to claim 1, characterized in that the flange (8) is provided with a concentric annular projection (9) on the end face on the side facing away from the bearing shaft, wherein the sealing means (5) bears against the projection (9).

9. A hub drive according to claim 1, wherein oil guide holes (13) are provided in the flange plate (8) for guiding the lubricating oil flowing into the sealing means (5) back to the interior of the hub drive.

10. A vehicle, characterized in that the vehicle has a hub drive according to any one of the preceding claims.