GB1600682A - Linking device for fitting an axle bearing to a railway vehicle - Google Patents

Description

(54) LINKING DEVICE FOR FITTING AN AXLE BEARING TO A RAILWAY VEHICLE (71) We, SOCIETE ANONYME USINES EMILE HENRICOT, a body corporate organised and existing under the laws of Belgium, of 1490 Court-Saint Etienne, (Belgium) do hereby declare the invention for which we pray that a patent may be granted to us, and the process by which it is to be performed, to be particularly described in and by the following statement: The present invention pertains to a linking device for the fitting of an axle bearing on a railway vehicle of the type of which the rolling elements are axles, each of which mainly consists of a shaft upon which two wheels are keyed and which is provided with two stub axles which rotate in bearings or journal-boxes upon which the vehicle rests.

Vehicles of this type are widely used on networks all over the world. When the axles of the vehicles have not been given a sufficient possibility of orientation with respect to the longitudinal axis of the vehicle, the negotiation of curves with small radius will cause the rapid wear of the wheel flanges and of the rails, entailing considerable maintenance costs.

The means which have been suggested up till now in order to achieve the required possibility of orientation are gener ally elaborate and costly, and even rather delicate.

The purpose of the present invention is to supply a simple, efficient and economy cal solution to the above-mentioned problem.

In further accordance with the invention, this purpose is accomplished by a linking device which comprises two extra bearing surfaces, a first of which is securable functionally integral with that part of the vehicle which is intended to rest on the bearing, and the second of which is securable functionally integrally with the latter, these surfaces being shaped in such a manner that they can roll upon each other around instantaneous axes which are parallel with the axis of rotation of the axle concerned, means being provided to prevent any slippage between the aforesaid surfaces.

For a better understanding, the present invention is described hereinafter in detail, by way of example, with reference to the appended illustrating but non-restricting drawings, in which: Figure 1 shows an elevaiton view of the linking of an axle bearing to a side member applying the device of the invention; Figure 2 shows a partial cross-section according to line 11-11 in Figure 1; Figure 3 is a top view of Figure 1; Figure 4 shows an exploded view of the elements of Figure 1; Figure 5 shows an exploded view of an alternative arrangement of the stops which prevent slippage; Figure 6 shows part of the section of the contact area by the median plane which is perpendicular to the axle axis, in the particular case when the contact surfaces are of cylindrical shape;; Figure 7 shows an elevated view of an example of application of the invention to the case of a vehicle provided with a primary stage of springing on journal boxes; Figure 8 shows an exploded view of the main elements of Figure 7.

In the example illustrated in figures 1 to 6, a link must be established between side members 1 (only partially shown) of a railway vehicle and axles 2, each mainly consisting of a shaft 3 upon which two wheels are keyed, one of which only being shown in 4, the shaft 3 being terminated at both of its ends by a stub axle 5 which rotates in a journal box or bearing 6, for instance of the " cartridge bearing", type, commonly used in railway technique.

For each of bearings 6, the corresponding side member I is provided with a bearing surface 7 as well as with two stops 8 located on either side of the latter.

A spacing element 9, which is shaped so as to fit on bearing 6, is located on the latter. The upper part of this element 9 forms a support surface 10, intended to cooperate with bearing surface 7.

Surfaces 7 and 10 are shaped so as to be able to roll over each other around instantaneous axes which are parallel to the rolling axis A of axle 2. For this purpose, the sections of these surfaces by a plane which is median with respect to bearing 6 and perpendicular to axis A take the shape of two curves which are reciprocally tangent to each other, the complete surfaces 7 and 10 being determined by generatrices, straight lined or curved, which bear along aforesaid two curves as director curves.

In the specific example of Figures 6, aforesaid director curves are circular arcs, the generatrices being straight lines parallel to axis A. Moreover, the axis of curvature of surface 10 (radius r) coincides with axis A, whereas the axis of surface 7 (radius R) is located in a vertical plane B-B which contains axis A.

In order to avoid any slippage between surfaces 7 and 10, a clearance 11 is provided at the center of each side wall 12 of part 9. Each clearance 11 is shaped to as to engage the corresponding stop 8 of side member 1 under consideration.

In the alternative shown in figure 5, part 9 is provided with two lugs 15 located on either side of the latter, the contour of which is shaped so as to engage pairs of stops 16, which are integral with side member 1 and are located on either side of bearing surface 7.

The longitudinal movements of part 9 with respect to side member 1 are limited by stops 13 of the side member, which engage the end surfaces 14 of part 9.

The movements of part 9 in the transverse direction (in ihe direction of axis A) are prevented by the cooperation of extensions 15 of the side surfaces of aforesaid part with the grooves 16 in the housing of bearing 6.

The above-described device thus permits the rolling without slippage of pressing surface 10 on bearing surface 7. This gives rise to two distinct components at the level of the stub axle 5: -a translation of the bearing in longitudinal direction, which realizes the desired effect; -a rotation of the bearing upon itself, permitted by the actual freedom of rotation of the bearing on its journal or respectively its stub axle.

If the materials were undeformable, the contact between surfaces 7 and 10 would occur in one point or along a generatix.

In practice however, the pressure created by the vertical load of the vehicle causes a deformation of the material, thus giving rise to a contact zone, the area of which depends upon the rigidity of the materials used.

In the course of the above-described movements of the bearings, this contact zone moves siultaneously on each of surfaces 7 and 10, thus subjecting the materials in contact to deformation cycles.

The energy dissipated in consequence thereof dampens the longitudinal movements of the bearings. This phenomenon enhances the dynamic stability of the vehicle.

In the case of figure 5, the link boasts a longitudinal rigidity (k), the value of which is independent of the amplitude of relative movement of surfaces 7 and 10, and inversely proportional to the difference of the radii (R and r). The magnitude of this rigidity is proportional to the vertical load (P transmitted to the bearing (k= Rr The invention can also be applied when a stage of springing of the vehicle is located on the bearings, as in the example illustrated in Figures 7 and 8.

In this example, the suspension springs 20 support the bogie or vehicles chassis 21 and rest on a bed plate 22. The latter slides vertically and transversely between guides 23 which are integral with chassis 21. In a particular form of embodiment, this bed plate 22 may be applied in the longitudinal direction against one of aforementioned guides 23 by the effect of one or several friction blocks, not shown, which are part of the dampening device of the springing.

The bed plate 22 is provided with a central opening 24 into which fits the bearing.

The latter may be built according to two alternatives: either with a body 25 (called journal box) comprising, at its top, surfaces 26 having a shape which is particular to the invention, and on either side, lugs 27, separated by a clearance 28 having shaped sides 29 in order to engage stops 30, which are integral with bed plate 22; or with a cartridge type bearing 31 which supports an adaptor 32 provided with elements 26, 27, 28 and 29 which are characteristic of the invention.

In each of these two alternatives, a longitudinal clearance 33 is provided between the bearing and the bed plate, so as to allow the required longitudinal relative movements for the radial orientation of the axles in a curve.

The advantages of such a linking device are numerous and of considerable importance.

By an appropriate choice of the curvature radii of the contact surfaces, extremely weak, or even zero or negative return forces can be generated. Consequently, such a linking device permits the orientation of the axle in 9 curve to be opposed by an extremely slight resistance, thus assuring the rolling of the vehicle in a bearings and the supports of the vehicle.

curve of small radium without the flanges of the wheels making contact with the rails.

This essential advantage must give rise to a considerable reduction of the wear on the wheels and rails and to an appreciable saving of maintenance costs.

By an adequate assorting of the materials and shapes of the parts in contact, return and dampening characteristics can be obtained which, when combined with the actual springing characteristics of the vehicle will assure a good dynamic stability at all operating speeds.

Due to its great simplicity the device is not at all costly, not one extra part is required with respect to the conventional arrangements used in railway technique.

The device can possibly further be applied to improve existing vehicles, by fitting sets of parts boasting contact surfaces with adequate curvatures between the The invention pertains to the linking device as well as to each of its characteristic constituent parts.

WHAT WE CLAIM IS: - 1. Linking device for fitting an axle bearing to a railway vehicle of the type described, comprising two extra support surfaces, a first of which is securable functionally integral with that part of the vehicle which is intended to rest on the bearing, and the second of which is securable functionally integral with the latter, these surfaces being shaped in such a manner that they can roll upon each other around instantaneous axes which are parallel with the axis of rotation of the axle concerned, means being provided to prevent any slippage between the aforesaid surfaces.

2. Device according to claim 1, wherein the said bearing and supporting surfaces are shaped in such a manner that in operation their section in a plane which is median with respect to said bearing and perpendicular to said axle are circular curves of different radius and which are tangent to each other, the full surfaces being determined by generatrices bearing on said first and second circular curves.

3. Device according to claim 2, wherein said second surface has an axis coinciding in operation with that of said axle, while said first surface has an axis in operation spaced from the axis of said axle and located in a vertical plane containing said axis.

4. Device according to claim 1, wherein at least one of said surfaces is part of a spacing element adaptor locatable between the corresponding part of the vehicle and/ or bearing.

5. Device according to claim 1, in which the means for preventing slippage of said surfaces comprises at least one set of stops which are in mutual engagement, at least one of which stops is securable functionally integral with the vehicle and at least another one of which stops is securable functionally integral with said bearing, at least one of the stops of said set forming part of a spacing element, and at least one of said surfaces being part of said spacing element.

6. Device according to claim 5, wherein said set comprises a central stop and a pair of lateral stops.

7. Linking device lor fitting an axle gearing to a railway vehicle, substantially as hereinbefore described with reference to the appended drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (7)

**WARNING** start of CLMS field may overlap end of DESC **. of the wheels making contact with the rails. This essential advantage must give rise to a considerable reduction of the wear on the wheels and rails and to an appreciable saving of maintenance costs. By an adequate assorting of the materials and shapes of the parts in contact, return and dampening characteristics can be obtained which, when combined with the actual springing characteristics of the vehicle will assure a good dynamic stability at all operating speeds. Due to its great simplicity the device is not at all costly, not one extra part is required with respect to the conventional arrangements used in railway technique. The device can possibly further be applied to improve existing vehicles, by fitting sets of parts boasting contact surfaces with adequate curvatures between the The invention pertains to the linking device as well as to each of its characteristic constituent parts. WHAT WE CLAIM IS: -

1. Linking device for fitting an axle bearing to a railway vehicle of the type described, comprising two extra support surfaces, a first of which is securable functionally integral with that part of the vehicle which is intended to rest on the bearing, and the second of which is securable functionally integral with the latter, these surfaces being shaped in such a manner that they can roll upon each other around instantaneous axes which are parallel with the axis of rotation of the axle concerned, means being provided to prevent any slippage between the aforesaid surfaces.

2. Device according to claim 1, wherein the said bearing and supporting surfaces are shaped in such a manner that in operation their section in a plane which is median with respect to said bearing and perpendicular to said axle are circular curves of different radius and which are tangent to each other, the full surfaces being determined by generatrices bearing on said first and second circular curves.

3. Device according to claim 2, wherein said second surface has an axis coinciding in operation with that of said axle, while said first surface has an axis in operation spaced from the axis of said axle and located in a vertical plane containing said axis.

4. Device according to claim 1, wherein at least one of said surfaces is part of a spacing element adaptor locatable between the corresponding part of the vehicle and/ or bearing.

5. Device according to claim 1, in which the means for preventing slippage of said surfaces comprises at least one set of stops which are in mutual engagement, at least one of which stops is securable functionally integral with the vehicle and at least another one of which stops is securable functionally integral with said bearing, at least one of the stops of said set forming part of a spacing element, and at least one of said surfaces being part of said spacing element.

6. Device according to claim 5, wherein said set comprises a central stop and a pair of lateral stops.

7. Linking device lor fitting an axle gearing to a railway vehicle, substantially as hereinbefore described with reference to the appended drawings.