Wheel bearing connector and seal unit

To permit a reliable, compact, low vibration, lightweight wheel bearing unit having a small number of components and useful for the driven wheels of a motor vehicle, there is a connecting part fastened between the bearing arrangement on the wheel flange and a joint bell at the wheel hub and the connecting part extending between them providing elastic damping by the construction thereof.

BACKGROUND OF THE INVENTION 
The invention relates to a wheel bearing unit of simple construction with a 
bearing arrangement and a joint bell, and particularly relates to a 
connection between these two elements. 
DESCRIPTION OF THE RELATED ART 
Wheel bearing units for motor vehicles are known, for example, from FAG 
Publication No. 05119DA entitled "Kraftfahrzeug-Radlagerungen" 
Motor-vehicle wheel bearing arrangements!. The bearing arrangement and 
the joint bell are generally braced against one another and are secured 
together by a screw connection. The primary task of the screw connection 
is to hold the bearing inner races together, particularly during 
cornering, and to fix the joint axially against the bearing. 
The wheel bearing arrangement in German Patent 2,542,917 is capable of 
being fitted with ABS. Its pulse ring is integrated as a metallic insert 
into the bearing seal. German Patent 4,134,434 proposes to design the 
pulse generator as axial toothing on the wheel bearing carrier. Moreover, 
German Offenlegungsschrift 3,126,192 discloses a bearing unit in which the 
joint bell is manufactured from fiber reinforced plastic. However, a 
bearing unit of this kind is not suitable for the transmission of high 
power. 
To decouple and damp vibrations from the drive shafts, the joint bell and 
the wheel bearing arrangement are usually screwed together axially. The 
disadvantages of the screw connection are that it is complex and expensive 
in its manufacture and assembly, the connection is heavy and there are 
risks of the formation of fretting corrosion or wear and of corrosion 
between the bearing arrangement and the joint bell. 
SUMMARY OF THE INVENTION 
It is an object of the present invention to further develop a wheel bearing 
unit of the type herein described such that a compact, reliable, low 
vibration and light weight unit is formed from a small number of 
components and also to permit a construction which is advantageous in its 
manufacture and assembly. 
The object is achieved by the features now described. The connecting part 
is fastened positively to the joint bell and the bearing arrangement on 
the wheel flange. This positive connection can be made using projections 
on the connecting element which stop at the grooves in the bearing 
arrangement and/or the joint bell. The connecting element may also serve 
as a sealing element, a damping element, a slinger disk and/or signal 
generator. Embedded magnetic or ferromagnetic material in the connecting 
element may serve as the signal generator. The connecting element is 
preferably of T-shaped cross section including a leg that extends between 
the bearing element of the wheel flange and the bell on the hub. The 
connecting element is preferably of plastic material or of elastic design. 
The connecting element between the bearing arrangement and the joint bell 
is a T-shaped seal, which not only prevents the penetration of dirt and 
water and hence the formation of rust, but simultaneously serves as an 
axial retaining, fixing and damping means without involving expensive 
manufacture and assembly. It can, in addition, also assume the function of 
signal generation in the radial or axial direction. An elastic recess or 
an axial spring element can be provided in the region of contact between 
the joint bell and the bearing arrangement in order to achieve freedom 
from play. 
Other objects and features of the present invention are explained with 
reference to an exemplary embodiment and will become apparent from the 
following description of the invention which refers to the accompanying 
drawings.

DETAILED DESCRIPTION OF THE INVENTION 
In FIG. 1 a bearing arrangement 1 cooperates with a joint bell 2. The joint 
bell can be designed either as a fixed or a mobile joint. A connecting 
element 3 is arranged between the bearing arrangement and the joint bell. 
The element 3 is fastened to the bearing 1 and to the joint bell 2 by 
means of projections 4 which snap into grooves 5 preformed in the bearing 
and the bell. For signal generation, e.g. for detecting the wheel speed, 
the connecting element 3 is provided with embedded magnetic or 
ferromagnetic elements 6 which extend radially or axially. It is also 
possible for a ferromagnetic ring or flange with gaps to be provided 
instead of the embedded elements. 
As can be seen from FIG. 2, the connecting element 3 extends radially 
inward in the region between the bearing arrangement and the joint bell 
where the element 3 forms an elastic projection 7. To achieve freedom from 
play, the projection is provided after assembly with elastic recesses or 
it has an axial spring 8. 
To transmit torque to the vehicle wheel, the joint bell 2 and the wheel 
flange 9 are provided with radial toothing 10. The inner races of the 
bearing arrangement 1 are connected rigidly and permanently to the wheel 
hub 9 by a positive connection produced by roll riveting. 
Although the present invention has been described in relation to a 
particular embodiment thereof, many other variations and modifications and 
other uses will become apparent to those skilled in the art. It is 
preferred, therefore, that the present invention be limited not by the 
specific disclosure herein, but only by the appended claims.