DE102019207255A1 - Device for preloading a bearing arrangement for supporting a shaft of a drive train of a motor vehicle - Google Patents

Abstract

A device is proposed for preloading a bearing arrangement (1) for supporting a shaft (2) of a drive train of a motor vehicle, in particular a bearing arrangement (1) for supporting a pinion shaft (2) of an axle drive, an axle drive or an angular drive of a motor vehicle, which as Conical outer ring (5) is designed, which forms a conical interference fit with a bevel (8) provided on the shaft (2) or with a conical inner ring (6) provided on the shaft (2) and is prestressed.

Description

The present invention relates to a device for preloading a bearing arrangement for supporting a shaft of a drive train of a motor vehicle, in particular a bearing arrangement for supporting a pinion shaft of a final drive, an axle drive or an angular drive of a motor vehicle according to the preamble of claim 1.

Axle drives are used to transmit the torque output by a drive unit or a gearbox to the drive wheels of a motor vehicle. It is known from the prior art to use bushings or adjusting disks to set the required bearing preload of a pinion shaft of an axle drive.

Furthermore, to set the required bearing preload of a bearing arrangement for mounting a pinion shaft, plastically preloaded bushings can be used which are plastically deformed during assembly. The preload force is set via the path and geometry of the bushes.

Disadvantageously, the assembly and use of such sockets results in a high load on the pinion shaft, the assembly proving to be costly. In order to enable the use of a plastically pre-stressed bush, the pinion shaft is strongly notched on the axial contact of the bush, with the bending moment being highest in this area, which corresponds to the area of a critical radius. In addition, the characteristic curve drops sharply and becomes fully plastic above a value, so that the bushing reduces the bearing preload, which leads to a reduction in service life.

Another disadvantage is that the different torsional stiffness of the materials causes a relative movement that leads to a perceptible squeak; Furthermore, a new geometry of the bushing is required to change the pretensioning force, the space required for the bushing being larger and also reducing the outer diameter of the drive shaft.

The present invention is based on the object of specifying a device for preloading a bearing arrangement for supporting a shaft of a drive train of a motor vehicle, in particular a bearing arrangement for supporting a pinion shaft of an axle drive, an axle drive or an angular drive of a motor vehicle.

This object is achieved by the features of claim 1. Further embodiments and advantages according to the invention emerge from the subclaims.

Accordingly, a device for preloading a bearing arrangement for supporting a shaft of a drive train of a motor vehicle, in particular a bearing arrangement for supporting a pinion shaft of an axle drive, an axle drive or an angular drive of a motor vehicle, is proposed, which is designed as a conical outer ring that is connected to a shaft provided chamfer or with a conical inner ring provided on the shaft forms a conical interference fit and is plastically pretensioned.

The outer cone ring is preloaded by pressing, which generates a non-linear displacement-preload force characteristic. In the event that a conical inner ring is provided on the shaft, this is supported, viewed axially, on a shoulder of the shaft.

The pre-tensioning force and the non-linear displacement-pre-tensioning force characteristic curve are clearly determined by the cone angle of the cone connection, which assumes values above 0 °, the coefficient of friction in the cone connection, the material of the cone outer ring, the pressing path of the cone connection and the area of the cone outer ring ; Changes to the preload force can easily be carried out by changing the influencing parameters mentioned.

According to the invention, the path-pretensioning force characteristic curve can also be set as a function of the contour of the surfaces of the conical outer ring and the conical inner ring or the chamfer.
With the concept according to the invention, a bearing preload with a predetermined preload force and press-in path can be set using suitable values of the influencing parameters.

Squeaking is advantageously avoided by the concept according to the invention, since a relative movement of the two conical rings to one another is excluded. In addition, the pre-tensioning force does not decrease with increasing travel, since a collapse of the conical outer ring is excluded, with the setting of the bearing and the rolling torque being process-reliable.

Furthermore, the device according to the invention for preloading a bearing arrangement reduces the manufacturing costs and possibly also the assembly costs compared with the solutions known from the prior art. Another advantage is that the overall length of the conical outer ring is short, so that, viewed axially, installation space is made available. In addition, the strength of the shaft is increased since there is no notch point on the shaft and thus the critical radius is no longer required.

• 1: Eine schematische Schnittansicht einer nach dem Stand der Technik ausgeführten Vorrichtung zum Vorspannen einer Lageranordnung zur Lagerung einer Ritzelwelle eines Achsgetriebes eines Kraftfahrzeugs;
• 2: Eine schematische Schnittansicht einer ersten Ausführungsform einer gemäß der Erfindung ausgeführten Vorrichtung zum Vorspannen einer Lageranordnung zur Lagerung einer Ritzelwelle eines Achsgetriebes eines Kraftfahrzeugs; und
• 3: Eine schematische Schnittansicht einer zweiten Ausführungsform einer gemäß der Erfindung ausgeführten Vorrichtung zum Vorspannen einer Lageranordnung zur Lagerung einer Ritzelwelle eines Achsgetriebes eines Kraftfahrzeugs.

The invention is explained in more detail below with reference to the accompanying figures. The components relevant to the invention are provided with reference symbols. Show it:

• 1 : A schematic sectional view of a device designed according to the prior art for preloading a bearing arrangement for supporting a pinion shaft of an axle drive of a motor vehicle;
• 2 : A schematic sectional view of a first embodiment of a device designed according to the invention for preloading a bearing arrangement for mounting a pinion shaft of an axle drive of a motor vehicle; and
• 3 : A schematic sectional view of a second embodiment of a device designed according to the invention for preloading a bearing arrangement for mounting a pinion shaft of an axle drive of a motor vehicle.

In 1 is a device for preloading a bearing assembly 1 for mounting a pinion shaft 2 shown in which a plastically pre-stressed bush 3 is used, which is plastically deformed during assembly. The preload force is determined by the path and geometry of the bushing 3 set.

To use the plastically pre-stressed bushing 3 to enable, has the pinion shaft 2 on the axial contact of the bush 3 on the pinion shaft 2 a notch 4th on, whereby the bending moment is highest in this area. The pinion shaft 2 is by using the socket 3 exposed to high stress, being through the notch point 4th the strength of the pinion shaft 2 is reduced. Furthermore, the characteristic curve drops sharply, so that the socket 3 above a certain value for those on the socket 3 acting axial force can decrease, which leads to a higher load on the bearings and reduces their service life.

According to the invention and referring to 2 is according to the invention a device for preloading a bearing arrangement 1 for mounting a pinion shaft 2 proposed which as a cone outer ring 5 is executed, which with one on the pinion shaft 2 provided cone inner ring 6th forms a conical interference fit and is prestressed. How out 2 can be seen, the inner cone ring is supported 6th viewed axially on one shoulder 7th the pinion shaft 2 from.

In the context of a further embodiment of the invention and with reference to 3 forms the outer cone ring 5 with one on the pinion shaft 2 provided bevel 8th a conical interference fit. According to the invention, the conical outer ring 5 preloaded by pressing in, creating a non-linear characteristic.

Within the scope of further, not shown embodiments of the invention, several devices designed according to the invention for preloading a bearing arrangement can be combined. It is also possible to use at least one pipe section that can be pressed onto a cone in order to additionally strengthen the conical interference fit.

Furthermore, viewed radially, one or more cylinder disks can be arranged one above the other above the conical outer ring, which are connected to each other or with the conical outer ring in a force-locking manner by static friction, the cylinder disks each having a different distance from the bearing arrangement before the preloading process. To preload a bearing arrangement, depending on the path, the cylinder disks are moved one after the other and then the conical outer ring axially, whereby the path-preload force characteristic can be influenced in a targeted manner.

List of reference symbols

1

Bearing arrangement

2

Shaft, pinion shaft

3

Rifle

4th

Notch

5

Cone outer ring

6

Inner cone ring

7th

shoulder

8th

chamfer

Claims (6)

Device for preloading a bearing arrangement (1) for supporting a shaft (2) of a drive train of a motor vehicle, in particular a bearing arrangement (1) for supporting a pinion shaft (2) of an axle drive, an axle drive or an angular drive of a motor vehicle, characterized in that it is as Conical outer ring (5) is designed, which forms a conical interference fit with a bevel (8) provided on the shaft (2) or with a conical inner ring (6) provided on the shaft (2) and is prestressed. Device for preloading a bearing arrangement (1) for mounting a shaft (2) of a drive train of a motor vehicle according to Claim 1 , characterized in that the cone Inner ring (6), viewed axially, is supported on a shoulder (7) of the shaft (2). Device for preloading a bearing arrangement (1) for mounting a shaft (2) of a drive train of a motor vehicle according to Claim 1 or 2 , characterized in that the conical outer ring (5) is preloaded by being pressed in, whereby a non-linear path-preload force characteristic is generated. Device for preloading a bearing arrangement (1) for mounting a shaft (2) of a drive train of a motor vehicle according to Claim 3 , characterized in that the preload force and the non-linear path-preload force characteristic curve are clearly determined by the cone angle of the cone connection, the coefficient of friction in the cone connection, the material of the cone outer ring, the press-on path of the cone connection and the area of the cone outer ring. Device for preloading a bearing arrangement (1) for mounting a shaft (2) of a drive train of a motor vehicle according to Claim 3 , characterized in that the non-linear displacement-preload force characteristic is also set as a function of the contour of the surfaces of the conical outer ring and the conical inner ring or the chamfer. Device for preloading a bearing arrangement (1) for mounting a shaft (2) of a drive train of a motor vehicle, according to one of the preceding claims, characterized in that viewed radially above the conical outer ring (5) one or more cylinder disks are arranged one above the other, which are through Static friction with each other or with the conical outer ring (5) are frictionally connected, the cylinder disks each having a different distance from the bearing arrangement (1) before the preloading process, the cylinder disks one after the other and then depending on the path to preload the bearing assembly (1) the cone outer ring can be moved axially, whereby the path-preload force characteristic can be specifically influenced.

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