The invention relates primarily to the field of work machinery or work vehicles, such as wheel loaders, dumpers (frame-steered vehicles), backhoes (excavator- loaders) and excavators. The present invention is furthermore intended for such work machinery of smaller dimensions (and lower weight), in particular for so- called"compact equipment".

The device for supporting a hub usually comprises a planetary gear set and forms a so-called final drive, or hub-mounted reduction gear. The wheel is then arranged rotationally locked on a hub and the planetary gear set is connected between a drive shaft and the hub. The drive shaft is driven by an angular gear, or center gear, which is in turn driven by the vehicle engine by way of a transmission system.

Arranging a planetary gear set on each drive wheel in this way produces a reduction in rotational speed from the drive shaft to the hub and an increase in torque from the drive shaft to the hub.

DESCRIPTION OF THE PRIOR ART The patent application WO 03/039900 describes an arrangement for supporting a wheel of a work vehicle.

The bearing here comprises a row of balls, which are accommodated in bearing races formed directly in the hub and in a housing part.

SUMMARY OF THE INVENTION An object of the invention is to provide a bearing device for a wheel, which creates the prerequisites for a device which is cost-effective to produce and is especially suited to lightweight work vehicles.

This object is achieved in that the roller bearing comprises a plurality of cable-like annular elements, which are arranged at an interval from one another and which together define a raceway in which a plurality of roller bodies are received. This bearing solution furthermore creates the prerequisites for a reduction in the number of constituent parts and makes the device more compact.

According to one embodiment of the invention the roller bearing comprises four cable-like annular elements and these are arranged so that they form the corners of a rectangle around the roller bodies. This provides a stable bearing arrangement in operation of the vehicle.

According to a further embodiment of the invention the hub comprises at least one seat for receiving a first of the cable-like elements, and the support part comprises at least one seat for receiving a second of the cable-like elements. This results in a stable bearing arrangement which creates the prerequisites for a long service life.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described in more detail below with reference to the embodiments shown in the drawings attached, in which Fig. 1 shows a schematic cross-sectional view of the device and

Fig. 2 shows a schematic perspective view of the roller bearing in Fig. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Fig. 1 shows a schematic side view of the device 1 for supporting a hub. The device 1 is arranged at one end of the axle casing or housing 3 of a wheel axle 2. A drive shaft 4 extends inside the axle casing 3. The drive shaft 4 is provided at one end 5 with a hub- mounted reduction gear 6 in the form of a planetary gear set. At its other end the drive shaft 4 is operatively connected to a center gear (not shown), which is driven by the engine of the vehicle via a prop shaft.

In accordance with the conventional art the planetary gear set 6 comprises a sun gear 7, a plurality of planet gears 8 and an internal ring gear 9, which are drive-connected to one another by way of gear teeth.

The device 1 comprises a hub 11, which also forms a planet carrier, which is designed to hold the planet gears 8. The planet gears 8 are more specifically supported on pins projecting axially from the hub 11.

In the preferred embodiment there are three planet gears 8, but one, two, four or more planet gears can be accommodated without departing from the scope of the invention.

The hub 11 is intended to carry a wheel (not shown) and is supported radially outside and against a support part 12. The support part 12 forms a section of the axle casing 3. In the embodiment shown the hub comprises an annular part 13 and a disk-shaped cover 14 fixedly connected to the annular part 13. The annular part 13 is arranged radially outside and supported against the axle housing. The annular part 13 and the disk-shaped cover 14 are securely connected together by way of a screwed connection 15. The cover 14 is arranged axially outside the planetary gear set 6 and

protects this from the external environment. The hub 11, and more specifically the cover 14, comprises said projecting pins, which form the planet carrier. The wheel is secured on the hub 11 by a conventional fastening arrangement (not shown), usually a bolted connection.

The device further comprises a brake device 16. The brake device 16 comprises a wet brake in the form of a disk brake. The brake device 16 comprises two sets of brake disks, which in operation rotate in relation to one another. A first set of brake disks (stator disks) is connected to a static part 18, in the form of the axle casing 3, arranged radially outside the planet carrier 11. The connection consists of a plurality, suitably four, pins 17 which are arranged in correspondingly shaped openings or drilled holes in the axle housing 3. The holes and hence the pins 17 are evenly distributed in the circumferential direction of the device. The stator disks are designed with correspondingly shaped openings at their periphery for the pins. As an alternative to the pinned connection a splined connection is also feasible. A second set of brake disks is rotationally locked to the drive shaft 4. The connection consists of a splined connection 19.

The brake disks are displaceable in the axial direction of said pins 17 or splined connection 19. Every other brake disk conventionally belongs to the first set and every second brake disk to the second set.

The brake device 16 further comprises a brake piston 26 for applying the brake by pressing the brake disks together, thereby increasing the friction between them.

Coupled to the brake piston is a duct 27 for delivering oil for application of the brake. On the opposite side of the brake disks to the brake piston 26, the internal ring gear 9 forms a pressure surface, or counter- surface, against which the disks are brought when applying the brake. A locking ring 28 is arranged

axially outside the internal ring gear 9 for locking this to the axle housing 3. A seal 29 is furthermore arranged between the hub 11 and the axle housing 3 for sealing off the space for the roller bearing 20.

A roller bearing 20 is arranged between the hub 13 and the axle casing 3, see Fig. 2. The roller bearing comprises a plurality of wire or cable-like, annular elements 21, which are arranged at a distance from another and which together define a raceway, in which a plurality of roller bodies 22 are received. Each of the cable-like elements 21 has a circular annular shape, viewed in the axial direction of the device.

Each of the cable-like elements 21 furthermore has an essentially circular cross-sectional shape.

The cable-like elements 21 are distributed at essentially equal intervals around the roller bodies 22. According to the embodiment shown in Fig. 2, the roller bearing 20 comprises four cable-like, annular elements 21 and these are arranged so that they form the corners of a rectangle around the roller bodies 22.

Each of the cable-like, elongate elements 21 comprises an internal seat 23 for contact with the roller bodies 22. The cable-like elements 21 may be made, for example, of hardened steel, preferably spring steel.

The cable-like elements 21 are furthermore fastened radially outwards to the hub 13 and radially inwards to the axle casing 3. The hub 11 comprises at least one seat 24 for receiving the two radially outer cable-like elements. These two cable-like elements therefore bear with an outer surface against the hub 13.

The support part (the axle housing) 12 comprises a seat 25 for receiving the two radially inner cable-like elements 21. These two cable-like elements therefore bear with an outer surface against the support part 12.

All cable-like elements 21 therefore bear with an inner surface against the roller bodies 22.

Such a bearing is often termed a four-point bearing in that four surfaces are ground for contact with the balls, see the seats 23 in the cable-like elements 21.

The term"race"is intended to signify that a surface area is formed for receiving the roller bodies 22.

This surface area usually has an arched or angled shape.

The roller bodies 22 consist of balls or rollers, which are distributed around the raceway along a circular path.

The roller bearing comprises a holder 26 for holding the roller bodies 22 at a distance from one another along the raceway. The holder 26 here comprises an elongate belt with openings for the roller bodies 22.

The holder 26 is made of a plastic material, for example, such as a thermoplastic or thermosetting plastic, preferably polyamide.

The scope of the term annular shape of the cable-like elements encompasses not only closed shapes but also the existence of interruptions in the circumferential direction.

The invention must not be regarded as being limited to the exemplary embodiments described above, a number of further variants and modifications being feasible without departing from the scope of the following claims.