Bearing unit

The invention refers to a bearing unit for driven or non-driven wheels of vehicles. The unit incorporates an inner member (5), an outer member (1) with intermediary rolling bodies (2) and retainer (10) and seals (11). The inner member (5) is provided with a flange-like member (7) for attachment of the unit to a wheel or to a vehicle. The invention is characterized thereby that the flange-like member (7), which extends radially outside the rolling bodies (2), has recesses (14), which make it possible to mount and inspect the retainer (10) and/or the seal (11) from the exterior of the flange-like member (7).

BACKGROUND AND SUMMARY OF THE INVENTION 
The present invention refers to a bearing unit for driven or non-driven 
wheels of vehicles or the like. 
Wheels e.g. for motor cars are conventionally supported on rolling bearings 
arranged on a shaft pivot. As such an assembly it is necessary accurately 
to machine a number of contact surfaces of the bearings, the shaft pivot 
or the surrounding housing or hub and to adjust the bearings to a correct 
preload in situ. 
In later years it has been suggested to substitute the conventional 
supporting method by arranging a bearing unit, which incorporates bearing 
as well as wheel hub. This unit can be attached directly to a supporting 
portion of the vehicle and the wheel can be fitted directly to the part of 
the unit intended for rotation. A plurality of types of such units are 
presently known, and one of them is described e.g. in British Patent 
Specification No. 1.519.048. 
The unit described in this patent consists of a rotatable inner member 3, a 
stationary outer member 2 and a two-row angular contact ball bearing 10. 
The bearing as shown is provided with a double retainer 11, which encloses 
both rows of balls. The unit is furthermore provided with two seals 12 and 
13 of which seal 13 has been given a particular design, whereas the easily 
accessible seal 12 is of conventional type. 
In assembling a bearing unit of this type, it is necessary to use the so 
called Konrad assembly, which means that the outer and inner rings are 
given an eccentric position in relation to each other during the 
introduction of the balls, whereupon the rings are brought to concentric 
position relative to each other and the retainer is inserted from one 
side, i.e. from the right hand side as shown in the drawing figure. It is 
thus necessary that the retainer is of the so called snap-type. It is also 
necessary that the seal 13 is made of such an elastic material that it 
will not impede an eccentric dislocation of the outer and inner rings 
relative to each other during the introduction of the balls. It is easily 
realized at a glance at the drawings that the seal 13 must be fixed to the 
outer ring 2 prior to the assembly of the bearing unit. 
It has since long been a desideratum to be able to use a conventional seal 
at this bearing unit also in the space adjacent the inner and outer race 
rings, and to be able to use a separate retainer for each row of balls. A 
common seal, as for example the seal 12 is rigid, and it can therefore not 
be fixed to the outer ring prior to a Konrad-assembly, since it will 
prevent an eccentric dislocation of the inner and outer rings relative to 
each other. A further study of the drawings of said specification shows 
furthermore that it is impossible to introduce a retainer for the left 
hand row of balls, as there is no space for displacing the retainer to the 
left prior to the assembly. 
This problem has according to the present invention been solved and it has 
been provided a bearing unit for driven or non-driven wheels of vehicles 
or the like, which incorporates a radially inner member and a radially 
outer member have confronting raceways for a plurality of rolling bodies 
or elements, retainer and seals arranged therebetween, whereby at least 
the radially inner member is provided with flange-like members for 
attachment of the unit to the wheel or the vehicle or the like, and which 
is characterized thereby that the flange-like member, which extends 
radially outwardly beyond the rolling bodies, is provided with recesses 
which make possible mounting and inspection of retainer and/or seals from 
the exterior of the flange-like member. 
Further features of the invention are defined in the sub-claims. 
By means of the present invention is it possible by aid of a simple tool to 
push the retainer and the seal, or if a double retainer is used, only the 
seal, into the bearing from the flange side. 
As to the seal it is besides the simplfied assembly also gained that it is 
possible to use a rigid seal of conventional type, as the seal does not 
have to be inserted during the Konrad-assembly.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
In FIG. 1 is shown a bearing unit having an outer race ring 1, which is 
common for both ball rows 2 of a two-row angular contact ball bearing. The 
outer race ring is equipped with a flange 3 provided with bolt bores 4 for 
the attachment to the vehicle. 
Inside the ball rows 2 there is arranged an inner rotatable member 5, which 
incorporates one half of a driving joint 6 and a flange-like member 7. The 
inner and outer rotatable members have confronting raceways for the 
rolling elements. The flange-like member 7 is equipped with bolt bores for 
fitting of wheel and brake disc. For guiding the wheel and the brake disc 
there is provided a tubular projection 9 at the inner member 5. 
Both rows of balls are retained in position by means of similar single 
retainers 10, which are each snapped onto the ball rows one from each 
direction. Similar seals 11 at each side of the ball rows prevent 
penetration of dirt and the like into the annular space for the rolling 
elements. As shown in the figure the distance D between the flange-like 
member 7 and the outer race ring 1 has been made so large that there is 
room for a retainer 10 between the flange-like member 7 and the ball row 
shown to the left in the drawing. The retainers and seals are during the 
inserting of the balls retracted in opposite directions in the drawings. 
In FIG. 2 is more clear shown how the flange-like member 7 consists of a 
plurality of circumferentially spaced lugs 12 with intermediate recesses 
14 which expose and permit access to the seals and retainers from 
exteriorly of the flange member 7. Other reference numerals are the same 
as those in FIG. 1. It is evident that it is easy to reach the seal 11, 
which is almost completely exposed on the drawing, through the recesses 
14. 
In one of the attachment lugs 12 there has been drilled a bore 13 for 
attachment of a conventional brake disc or brake drum (not shown), so that 
the wheel can be removed independently. 
FIG. 3 shows another embodiment of the invention, in which the flange-like 
member more clearly has been made in form of a flange and where recesses 
14 in form of openings in the flange have been arranged to give access for 
pushing retainer and seal 11 into the bearing. 
The device according to the present invention gives, as already mentioned, 
the advantage as compared to earlier similar devices that single retainers 
and standardized, rigid seals can be used and that the assembly will thus 
be simple and easy to assemble and disassemble. As the flange-like member 
consists of four lugs only it is furthermore achieved the advantage, that 
the heat transfer from brake disc or brake drum to the bearing will be 
less than with earlier similar designs. This depends on a smaller metallic 
contact surface between flange and brake disc or brake drum and a better 
air cooling in the larger space between the flange and ball rows. Due to 
the fact that the flange has been provided with large recesses the weight 
will be lower. At the dimension shown in the drawings an amount of about 
0,7 kg of steel is saved as compared with a flange having no other 
recesses than the bolt bores. 
The invention is not limited to the embodiments shown but can be modified 
in different ways within the scope of the claims.