GB2033976A - A Method of Manufacturing a Ring Bearing Element - Google Patents

Abstract

A method of manufacturing a ring bearing element comprises the steps of deforming an elongate strip to produce a strip with a cross-section having a first limb (7) for defining a bearing track (8) and a second curved limb (5), integral with the first limb (7), which limbs mutually merge along a region extending axially of the strip and have free end portions generally disposed in a common plane and which at the region of merging the limbs (5, 7) extend substantially perpendicularly to each other and to the axis of the strip, uniting the axial end portions of the strip with each other to produce a ring and thereafter straightening the second limb (5). <IMAGE>

Description

SPECIFICATION A Method of Manufacturing a Ring Bearing Element The present invention relates to a method of manufacturing a ring bearing element of for example a bearing race particularly for link mounts of vehicle trailers.

German Democratic Republic commercial patent 29 375, class 63a, 12 discloses ball link mounts for trailers, which utilize commercially known angular profile material, the ball track of which is shaped cold after bending, aligning and welding the material into a ring. It is attained thereby, that relatively little effort is invested in the manufacture of the semi-product and the necessary deformation work is undertaken only during or after the bending operation, thus in the range of the stage of application of the starting material. These undisputed economic advantages in the production of the semi-product have however substantial technical defects as a consequence of cold shaping, for example as a result of rolling of the ball track.

Due to the large cold deformation, only material can be used which do not assure an optimum limiting useful life of the ball track.

Additionally, constructional compromises are necessary at the loadable looping angle of the ball track, since the transitions from the radius of curvature to the pitch plane of the ball track possess large radii for technological reasons.

By reason of the additional loading of the ball link mounts by tilting moments and inertia forces, especially through vertical force components in the transmission of the shape-locking securing forces between an upper link mount ring and a lower link mount ring, a play-free mounting in every plane of loading is necessary, which can not be attained satisfactorily from the state of the art disclosed in German Democratic Republic patent 29 375.

German Democratic exclusive patent 25 095, international class B 23p 15/00, discloses a process, by which a steel blank is reshaped by bending and welding into an endless ring, is subsequently clamped in between two planar pressure surfaces which permitting sliding of the ring in its plane and is stressed in this clamped position by the influence of radial forces over the entire circumference tangentially to above the flow limit. The ring is finished in shape into an exactly planar stress-free ring calibrated in diameter.

The above proposal is concerned with an apparatus for the stretching of the ring finished in shape, while there is no concrete contribution to the shaping of the starting material.

According to the present invention there is provided a method of manufacturing a ring bearing element comprising the steps of deforming an elongate strip to produce a first limb for defining a bearing track and a second curved limb, integral with the first limb, which limbs mutually merge along a region extending axially of the strip and have free end portions generally disposed in a common plane and which at the region of merging extend substantially perpendicularly to each other and to the axis of the strip, uniting the axial end portions of the strip with each other to produce a ring and thereafter straightening-the second limb.

The deforming operation may comprise hot rolling of steel rod.

The method may comprise so providing bearing journalling lines in the first limb as to leave spaces between surface portions of the track and a bearing when disposed in the track.

The lines may be provided before uniting the axial ends of the strip.

The lines may be provided after uniting the axial end portions of the strip.

The lines may be provided by rolling.

The rolling of the lines may be performed hot.

Embodiments of the present invention will now be more particularly described by way of example and with reference to the accompanying drawings in which: Fig. 1 shows a ball link mount with an upper and a lower ring of similar profile, Fig. 2 shows a ball link mount with an upper and lower ring of dissimilar profile, Fig. 3 shows the cross-section of a hot-rolled profile member for a ring shown in Fig. 1, Fig. 4 shows the cross-section of a hot-rolled profile member for the lower ring shown in Fig. 2, Fig. 5 shows the cross-section of the ball link mount shown in Fig. 1 after bending round of the profile members.

Fig. 6 shows the cross-section of the ball link mount shown in Fig. 2 after bending round of the profile members, and Fig. 7 shows the cross-section of the ball track after rolling of the carrying lines.

An embodiment having a generally Z-shaped profile is shown in Fig. 1 and comprises two like ring elements or profile members as shown in Fig.

3. The upper link mount ring 1 and the lower link mount ring 2 have the same cross-section 13 and are therefore bent round in opposite direction as shown in Fig. 6. This bending round takes place in such a manner that the unprofiled cross-section 13 of the lower link mount ring 2 points towards the centre of the link mount, while the unprofiled cross-section 1 3 of the upper link mount ring 1 points away from the centre of the link mount.

An embodiment havirig a generally shaped profile comprises the two dissimilar profile members shown in Fig. 3 and Fig. 4, arranged as shown in Fig. 5.

In, for example, the embodiment shown in Fig.

1, the profile members are profiled by hot rolling and cut to length from the rod. Through the bending of the profile members, for example by a three-roller bending machine, an open ring is subsequently produced, both the ends of which are undetachably connected by welding into a closed ring. Through subsequent profiling, for example rolling, the limb 5 is brought into the position 9 so that the limbs 5 and 7 together enclose a right angle 16 opposite the inside radius 6. Simultaneously, the hot-rolled ball track profile 8 is if necessary finished in profile.

In the embodiment shown in Fig. 2, the upper link mount ring 1' comprises the profile member shown in Fig. 3 and the lower link mount ring 2' comprises the profile member shown in Fig. 4.

After the bending-round and welding, the limb 5' is brought into the position 10 and the limb 7' into the position 11' by rolling. With the lower link mount ring 2' thus obtained, both limbs of the profile member shown in Fig. 4 are residually deformed after the bending round, whilst in the case of the upper link mount ring 1' and the upper link mount ring 1, only the limb 5 is residually deformed.

Carrying lines 14 and 14' may be introduced by hot-rolling into the ball track 8, whereby free spaces 15 and 15', which can be provided from outside with grease by means of lubricant nipples 4, are provided beside these carrying lines. The carrying lines may also be, if required, finished in profile and smoothed by the described profiling.

The ball link mount rings thus provided are subsequently expanded by means of known stretching and splaying devices and the final dimension is fixed free of stress.

The upper link mount ring 1 and the upper link mount ring 2 are finally, together with the ball series 3, shape-lockingly connected with one another, closed off and secured.

The above described exemplary method provides for the manufacture of ring bearing elements for use in large ball bearing races, particularly for link mounts of vehicle trailers, by which non-cutting shaping is possible without the disadvantages associated with the prior art.

Relatively high quality material can be used and high shaping accuracy of the entire cross-section is attained without nearly as much effort being necessary as perhaps during drawing of the starting material or in stock removal.

By non-cutting shaping, preferably by hot rolling, the starting profile containing the ball track of the upper link mount ring and lower link mount ring is predeformed or finished deformed and preprofiled or finished profiled so far that no noteworthy changes in cross-section of the profile are necessary through the following non-cutting processes such as bending round, welding, rolling, stretching and aligning, but simultaneously with the bending round of the upper ball link mount ring and the lower link mount ring merely a residual deformation of the position of the limbs of the ball bearing races to one another takes place.

Claims (10)

Claims

1. A method of manufacturing a ring bearing element comprising the steps of deforming an elongate strip to produce a first limb for defining a bearing track and a second curved limb integral with the first limb, which limbs mutually merge along a region extending axially of the strip and have free end portions generally disposed in a common plane and which at the region of merging extend substantially perpendicularly to each other and to the axis of the strip, uniting the axial end portions of the strip with each other to produce a ring and thereafter straightening the second limb.

2. A method as claimed in claim 1, wherein the deforming operation comprises hot rolling of steel rod.

3. A method as claimed in either claim 1 or claim 2, comprising so providing bearing journalling lines in the first limb as to leave spaces between surface portions of the track and a bearing when disposed in the track.

4. A method as claimed in claim 3, wherein the lines are provided before uniting the axial ends of the strip.

5. A method as claimed in claim 3, wherein the lines are provided after uniting the axial end portions of the strip.

6. A method as claimed in any one of claims 3 to 5, wherein the lines are provided by rolling.

7. A method as claimed in claim 6, wherein the rolling of the lines is performed hot.

8. A method of manufacturing a ring bearing element, substantially as hereinbefore described with reference to Figs. 1 to 6 of the accompanying drawings.

9. A method of manufacturing a ring bearing element, substantially as hereinbefore described with reference to Figs. 1 to 7 of the accompanying drawings.

10. A ring bearing comprising a ring bearing element manufactured by the method as claimed in any one of the preceding claims.