AU2013248232B2

AU2013248232B2 - Electric current return device for railway vehicles

Info

Publication number: AU2013248232B2
Application number: AU2013248232A
Authority: AU
Inventors: Roger Deleu
Original assignee: Ateliers Hubert Gerken SA
Current assignee: Ateliers Hubert Gerken SA
Priority date: 2012-10-26
Filing date: 2013-10-25
Publication date: 2016-12-15
Anticipated expiration: 2033-10-25
Also published as: EP2724913A1; PL2724913T3; AU2013248232A1; EP2724913B1

Abstract

ELECTRIC CURRENT RETURN DEVICE FOR RAILWAY VEHICLES 5 The present invention relates to an electric current return device arranged to be enclosed in a railway vehicle bogie provided with at least one axle supporting a wheel on each of its ends, each wheel comprising a hub, a front face and a connected face, each connected face being linked to one end of said axle, said support including a cavity arranged to house the contact disk. (Fig. 3) 12b 12a 1 -- 5 Fig. 3

Description

1

ELECTRIC CURRENT RETURN DEVICE FOR RAILWAY VEHICLES

Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of common general knowledge in the field.

Unless the context clearly requires otherwise, throughout the description and the claims, the words ‘comprise’, ‘comprising’ and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is to say in the sense of “including but not limited to”.

The present invention relates to an electric current return device arranged to be enclosed in a railway vehicle bogie provided with at least one axle supporting a wheel on each of its ends, each wheel comprising a hub, a front face and a connected face, each connected face being linked to one end of said axle, said device comprising: a) at least one contact disk comprising at least one conductive material, b) at least one brush comprising at least one conductive material, in contact with said contact disk, c) a support comprising at least one insulating material, d) a fastening means comprising at least one conductive material and arranged to secure said support to a railway vehicle bogie, to which said axle is fastened, said support being provided to support said contact disk, situated on the side opposite the wheel, and allow said contact disk or said brush to be joined to said conductive fastening means, e) a connecting piece comprising at least one conductive material and arranged to securely link said brush to said front face of the wheel, said brush optionally being securely linked to a brush holder.

Such an electric current return device is known from the state of the art and comprises a fastening hub that is for example a metal rod, preferably made from a transition metal or alloy thereof, extending the ends of an axle and secured to the bogie of the railway vehicle, and whereof a rod portion [followed by page 1a] 2013248232 18 Nov 2016 1a passes through the wheel at the center thereof through its hub. The support made from insulating material, which comprises a front face and a dorsal face, is passed through by part of the rod. The front face of said support is extended by two nozzles provided to engage a contact disk linked to said rod, such that 5 said contact disk is positioned protruding above the nozzles and situated on the side opposite the wheel. One face of the contact disk is thus securely connected to the front face of said support using a crosspiece.

The stability of said contact disk positioned protruding is ensured by elastic pads situated between the nozzles of said support and the dorsal face 10 of said contact disk. The device comprises an aluminum brush holder [followed by page 2] 2 provided with a removable brush made from metal-graphite on the one hand, and a conductive connecting piece in the form of an aluminum enclosure defining a cavity, closed on one side by said wheel and on the other by said brush holder such that the brush is in contact with said contact disk on the other hand.

This electric current return device, known from the state of the art, is particularly intended to be enclosed in a tram bogie whereof the platform is lowered and which comprises at least one bridge axle supporting the wheel on each of its ends. Said bogie comprises an access path to said electric current return device whereof the bore is smaller than that of the opening in which said brush holder is fitted.

When the railway vehicle moves, a current is generated at the electrical power supply equipment and tends to reach the ground by a preferred path. More specifically, this return electric current typically follows a route that passes through the wheel and its bearings toward the rails and the ground. Such a route poses problems inasmuch as it causes the production of electric arcs between the wheei and the bearing system, which are detrimental to the proper operation of the latter. The electric current return device is therefore used in railway vehicles to deflect the return electric current from its preferred path, from the electric power supply toward the ground, while avoiding the bearing system. For the returning electric current to follow the route well defined by the electric current return device, it is essential for the latter to comprise materials with a lower electrical resistivity than those making up the wheel and its bearing system. Consequently, the return current passing through the wheel to rejoin the ground is deflected by the conductive connecting piece, the brush that directs the current toward the contact disk, and lastly by rod, which is connected to the ground via the wheel by an electric discharge cabling.

During operation, in the known device, the brush, secured to the wheel by the aluminum enclosure, is therefore driven by the wheel and rubs against the frontal surface of the contact disk, which is stationary once it is secured to the bogie. This rubbing is on the one hand the source of wear of the brush and the frontal surface of the contact disk, and on the other hand generates a significant amount of dust that is detrimental to the proper operation of the bearing system. This dust is 3 therefore contained in the cavity of the aluminum enclosure by baffles. The wear dust accumulated in said cavity, however, pollutes the contact disk and the brush, which results in poorer electrical contact between those two pieces, and therefore poorer operation of the electric current return device. In order to mitigate the accumulation of significant quantities of wear dust in the cavity, said cavity has been separated in two by inserting a sealing device placed between the frontal surface of the contact disk and the inner wall of the enclosure at the brush-contact disk junction.

Regular cleaning of this cavity, the brush and the surface of the contact disk is therefore essentia! to ensure the efficiency of the electric current return device. The access to the cavity is provided by removing the brush holder fitted into said enclosure. In this context, the contact disk is positioned protruding so as to facilitate the cleaning of the frontal surface of the disk, thereby making it closer to said opening in which said brush holder is fitted.

Unfortunately, the contact disk as described in the prior state of the art has a low impact and vibration strength, despite the presence of elastic pads situated between the nozzles of said support and said contact disk, in fact, during operation, the wheels of the tram are greatly biased, whether upon each passage from one rail portion to another, when the journey has a curved segment, or during the braking and acceleration phases of the tram.

Furthermore, the accumulation of dust at the pads results in altering their elastic properties. This therefore results in a decrease in the strength of said contact disk with respect to impacts and vibrations. Furthermore, the elastic pads further make it possible to create tension between said brush and said contact disk. This tension makes it possible to preserve clear contact between the surface of said disk and that of the brush as the latter becomes worn. The alteration of the elastic properties of the pads no longer makes it possible to compensate for losses of material at the brush, which results in poorer contact between the surface of the contact disk and the brush, and therefore poorer electrical contact, which compromises the effectiveness of the electric current return device.

Stabilizers, secured to said support, have therefore been added to the device in certain existing versions with the aim of improving the strength of the contact 4 disk with respect to the impacts and vibrations intrinsic to the operation of the tram, giving the device a de facto complex construction.

The contact disk, like the brush, becomes worn and must be replaced regularly. Access to the electric current return device is provided by said access path of the bogie, and once the brush holder is removed, the brush can then be separated from the brush holder and replaced. Consequently, the fastening means may break following the various stresses inherent to the travel of the railway vehicle, in which case they must be replaced.

To replace the contact disk and the fastening means, it is necessary to remove the stabilizers and the sealing device, which cannot be done without disassembling the aluminum enclosure and therefore at least part of the bogie.

The disassembly and reassembly operation of said at least one part of the bogie and the aluminum enclosure, followed by the step for replacing the contact disk, takes approximately 16 hours. Given that a tram comprises at least four electric current return devices, the total maintenance period is estimated at more than two days, during which time the tram is immobilized. This immobilization for such a long length of time is expensive and seriously compromises the economic viability of the vehicle, particularly in light of the replacement frequency and the multiplication of vehicles in a city fleet.

The invention aims to offset the drawbacks of the state of the art by procuring an electric current return device with a simpler and more compact construction and allowing a quick disassembly and replacement of the contact disk.

To resolve this problem, according to the invention, a device is provided as indicated at the beginning of this document wherein said support includes a cavity arranged to house said contact disk, and wherein said conductive connection piece is an enclosure defining a cavity of the enclosure comprising a first and a second part of cavity, said enclosure being arranged to be closed on one side by the wheel and on the other side by said brush holder. Said first part of said cavity is arranged for housing the brush holder and the brush whereas said second part of said cavity is an area of wear dust retention in the shape of a dual baffle system. 5

In this way, the contact disk, included in the cavity of the enclosure, is stabilized by the cavity of the support, also included in the cavity of the enclosure, and the electric current return device according to the present invention has a simplified construction while making it possible to eliminate the presence of the stabilizers.

The fact that the contact disk is housed in the cavity of said support thus contributes to improve its stability by the improvement of its vibration and shock resistance the majority of which is absorbed by said outer casing, and thus to increase its lifespan.

Surprisingly, the presence of a cavity in the support to house the contact disk therein not only makes it possible to simplify the construction of the electric current return device, but also the disassembly and replacement of said contact disk exclusively through the access path of the bogie, since the device according to the invention no longer comprises the stabilizers and the sealing device. In this way, the step for disassembling the aluminum enclosure and therefore part of the bogie is eliminated, which makes it possible to reduce the maintenance time of the electric current return device considerably, from approximately 16 hours to approximately one hour.

The brush and Its brush holder are moreover stabilized by the first cavity and the electric current return device according to the invention has a simplified construction while making it possible to eliminate the presence of the stabilizers.

Furthermore, the space that was necessary to place the stabilizers is therefore replaced by an area with no dust retention, in the extension of the cavity of said support, by a double-baffle system, making the use of the retaining seal unnecessary.

In this way, the second cavity of the enclosure defining a cavity allows not only to retain the wear dust and thereby preserve the rotation of the wheel but also to store that dust far enough from the junction between the brush and the disk, such that this dust does not pollute the device and that the proper electric contact between said brush and said contact disk is guaranteed. 6

Moreover, the use of a closed enclosure as a conductive connection piece implies de facto that said part of said fastening means and said outer casing are arranged to pass through the wheel at the center thereof through the hub.

This particular embodiment in fact makes it possible for the fastening means not to come into contact with the closed enclosure. In one advantageous alternative according to the present invention, said fastening means are mounted in an outer casing comprising at least one rigid insulating material.

The major advantage of this alternative according to the invention lies in the fact that the strength with respect to the vibrations of said fastening means is increased while not altering its ability to conduct current.

In one specific embodiment, part of the outer casing is securely connected to the contact disk and is arranged to pass through the support.

In this particular arrangement, the outer casing acts as a guide, which makes it possible to facilitate the step for replacing the contact disk through the access path of the bogie and to reduce the time needed for upkeep for the electric current return device.

Advantageously, the brush is securely linked to a brush holder by a lug fastening system, such that the brush can be easily disassembled from its brush and replaced more simply.

Advantageously, the brush holder comprises at least one elastic material such as a spring.

The use of a brush holder with elastic properties makes it possible to create tension between the brush and the contact disk. This tension guarantees clean contact between the surface of the disk and that of the brush as the latter becomes worn.

Preferably, the contact disk comprises at least one metal material, for example such as bronze.

In the electric current return device according to the invention, the support comprises an electrically insulating material, preferably a dielectric material chosen from the group made up of epoxy polymers and glass fibers, for example impregnated, and combinations thereof. 7

Advantageously, said brush includes a metal-graphite, while the connecting piece comprises at least one metal material such as aluminum, for example.

Other embodiments of the electric current return device according to the invention will emerge from the appended claims.

The invention also relates to a method for disassembling an electric current return device enclosed in a bogie comprising a disassembling of said brush of the electric current return device, wherein said disassembling of said brush, and possibly of the brush holder, is realized by means of a gripping means provided on said brush or said brush holder and accessible from said frontal way, and wherein said brush is disassembled from the first part of the enclosure defining a cavity of said connection piece which houses and stabilizes said brush and said brush holder.

This disassembly method further comprises a step in which the brush is separated from its brush holder, and a step in which the contact disk is disassembled from the electric current return device using gripping means.

Furthermore, the invention relates to a method for assembling an electric current return device enclosed in a bogie comprising a mounting of a brush on a contact disk wherein said mounting of said brush, and possibly of the brush holder, is realized by means of a gripping means provided on said brush or said brush holder and accessible from said frontal way, and wherein said brush is mounted in the first part of the enclosure defining a cavity of said connection piece which houses and stabilizes said brush and said brush holder.

This method for assembling an electric current return device enclosed in a bogie comprises a step in which the brush is secured to the brush holder before said assembly step on the one hand, and a step for assembling a contact disk on the support using gripping means of the contact disk on the other hand.

Other embodiments of the methods according to the invention will emerge from the appended claims.

Other features, details and advantages of the invention will emerge from the description provided below, non-limitingly and in reference to the appended drawings: 8

Figure 1 is a diagrammatic top view of part of a railway vehicle bogie provided with two axles each supporting two wheels.

Figure 2 is a longitudinal cross-sectional diagrammatic view of an axle and a part of the bogie in which the device according to the invention is enclosed.

Figure 3 is a diagrammatic longitudinal cross-sectional view of the device according to the invention.

Figures 4a and 4b illustrate the steps of the method in longitudinal cross-section for disassembling the electric current return device, in which the brush as well as the brush holder and the contact disk are removed from the rest of the device, and respectively in which the brush, the brush holder as well as the contact disk are removed from the rest of the device.

Figure 1 is a diagrammatic top view of part of a railway vehicle bogie 1 provided with two axles 2 each supporting two wheels 3 on the ends, each wheel comprising a hub 4, a front face 5 and a connected face 6, the latter being linked to the end of the axle. The electric current return device 7 is placed in said bogie part that comprises a frontal access path 8 to the electric current return device.

When the railway vehicle moves on the rails R, the current generated at the electrical power supply equipment tends to reach the rails R, and then the ground, via the wheels 3 and their bearing system.

To prevent the current from passing through the wheel and the bearings, and thereby generating electric arcs, the current is deflected from the wheel and its bearings by said electric current return device 7.

Figure 2 is a diagrammatic longitudinal cross-sectional view of an axle and a part of the bogie in which the device according to the invention is enclosed, while figure 3 illustrates a diagrammatic longitudinal cross-sectional view of the device.

As shown in figure 2, the electric current return device according to the invention comprises fastening means 9, which for example consist of a rod comprising at least one conductive material, in the extension of the ends 10 of an axle 2, for example a bridge axle as illustrated in figure 2, and which is secured to said bogie 11 by said bridge axle 2, and a part of which passes through the wheel 3 in the center thereof by its hub 4. Said bogie 11 is arranged to receive the 9 platform on which the passenger compartment of said railway vehicle is placed upright.

As shown in figure 3, the electric current return device further comprises an insulating support 12a, 12b connected to said fastening means that secures the support to the bogie 11. The support includes a support cavity arranged to house at least one contact disk 13, situated on the side opposite the wheel, and to allow the latter to be in contact with the fastening means.

In this way, the contact disk is stabilized by the cavity of the support and the electric current return device according to the present invention has a simpler construction than that of the device as described in the prior state of the art.

Furthermore, the electric current return device comprises a conductive brush holder 14 provided with at least one removable conductive brush 15 and gripping means 22 on the one hand, and a conductive connection piece 16 assuming the form of an enclosure defining a cavity closed on one side by the front face 5 of the wheel and on the other side by the brush holder 14 or the brush 15, such that the latter is in contact with the contact disk, on the other hand. The conductive brush 15 is enclosed in a first cavity part 19 of the conductive enclosure 16.

In the specific embodiment of the invention as illustrated in figure 3, the fastening means 9 are a threaded rod whereof said part, which is arranged to close an orifice, optionally provided with a screw pitch, present on the contact disk, forms connecting means making it possible to link, preferably securely, said contact disk to said threaded rod, for example by screwing the latter to said rod part.

Furthermore, the threaded rod is mounted in an insulating outer casing 17 that for example assumes the form of a rigid tubing and whereof a part, which is arranged to close said orifice present on the contact disk and pass through an orifice present on said support 12a, 12b, constitutes connecting means making it possible to link, preferably securely, the rigid tubing to the contact disk.

Lastly, in the specific embodiment of the invention, the tubing part and the rod part pass through the wheel at the center thereof through its hub.

The electric current return device according to the invention makes it possible to deflect said current toward the ground by the conductive connecting piece 16, 10 the brush 15 that directs the current toward the contact disk 13, and lastly the fastening means 9, which are linked to the rails via the wheels 3 by electrical cabling.

During operation, in the device according to the invention, the brush 15 enclosed in the first cavity part 19 of the conductive enclosure 16 is driven and rotated by the wheel 3 to which it is secured and rubs against the contact disk 13, which is stationary once it is secured to the bogie 11 by the fastening means 9. This continuous rubbing wears down the surfaces of the contact disk and the brush, and is accompanied by a release of wear dust that builds up in the retaining area formed in the second cavity part 20. Due to its double-baffle form, the retaining area makes it possible to store the wear dust away from the interface between the brush and the contact disk.

As shown in figure 4a, said brush is preferably securely linked to the brush holder by a lug fastening system 18.

The cavity defined by the conductive connecting part assumes the form of a closed enclosure 16 as illustrated in figure 4b.

As shown in that figure, the cavity is intended to include the support and the contact disk as well as the brush, and comprises a first cavity part 19 and a second cavity part 20.

The first cavity part 19 is arranged to house the brush alone or with the brush holder, while the second cavity part 20 is a retaining area for the wear dust produced during the rubbing of the brush on the contact disk. Preferably, the retaining area is a double-baffle system.

As an illustration, figures 4a and 4b also summarize the main steps of the method for maintaining the electric current return device. This replacement process involves a method for disassembling and a method for assembling said electric current device.

The disassembly method comprises a step for accessing, through the frontal access path 8, the gripping means 22 provided on the brush 15 or the brush holder 14 of the electric current return device, and a step for disassembling the brush, optionally linked to the brush holder, using the gripping means, as illustrated in figure 4a. In figure 4a, the step for disassembling the brush and 11 optionally the brush holder is illustrated by the arrow pointing to the right. For example, the gripping means are a key positioned protruding on the brush, or optionally the brush holder, said key comprising a threaded rod complementary to a screw pitch of an orifice of the brush, or optionally the brush holder, in which it is intended to be screwed. Preferably, the threaded rod of the key is mounted in a tube whereof one of the ends is intended to fit on a connecting piece positioned protruding on the brush, or optionally the brush holder, when the threaded rod of the key is screwed into the screw pitch of the brush or brush holder.

The disassembly method further comprises a step in which the brush is separated from its brush holder, for example, by separating the brush holder from the lug fastening system and then separating the brush from the slotted lug, followed by a step in which the contact disk is disassembled, as illustrated in figure 4b by the arrow pointing to the right of figure 4b, from the electric current return device using gripping means 23, for example by unscrewing it from the threaded rod, which is dislodged from the cavity 21 of the support.

Once disassembled, the electric current return device is for example cleaned of any wear dust and optionally, the brush and the contact disk are replaced.

The method for assembling the electric current return device comprises a first step for bringing the brush, optionally secured to the brush holder, through the frontal access path 8 followed by a step for assembling the brush on the contact disk by linking the brush or brush holder to the connecting piece using the gripping means 22. In figure 4a, the step for assembling the brush and optionally the brush holder is illustrated by the arrow pointing to the left.

The method for assembling the electric current return device further comprises a step, preceding the step for mounting the brush on the contact disk, in which the brush is secured to the brush holder.

The step for assembling the brush on the contact disk is optionally preceded by a step for assembling the contact disk on the support of the electric current return device. In figure 4b, the step for assembling the contact disk on the support is illustrated by the arrow pointing to the left. 12

In the specific embodiment as described in figures 4a and 4b, the outer casing 9 serves as a guide, which makes it possible to facilitate the process of replacing the contact disk.

The present invention also relates to the specific or alternative embodiment of the electric current return device, as described above, in which the brush and optionally the brush holder are housed in the cavity of the support and the contact disk is linked to the conductive connecting piece.

In this context, the invention, in another alternative embodiment, pertains to an electric current return device in which the brush is arranged to be housed in the cavity of the support and to be linked to said fastening means, and in which the contact disk is intended to be linked to the conductive connecting piece.

Then, the enclosure is closed on one side by said front face of the wheel and on the other side by the contact disk, the first part of the cavity being arranged to house the contact disk.

In this electric current return device, the fastening means are a threaded rod whereof said part, which is arranged to close an orifice, optionally provided with a screw pitch, present on the brush, constitutes connecting means making it possible to link, preferably securely, the brush to the threaded rod, for example by screwing the latter to the rod part.

Furthermore, the threaded rod is mounted in an insulating outer casing that for example assumes the form of a rigid tubing and whereof a part, that is arranged to close said orifice present on said brush and to pass through an orifice present on said support, constitutes connecting means making it possible to link, preferably securely, the rigid tubing to the brush.

Consequently, the invention relates to an alternative method for disassembling an electric current return device of a bogie from the frontal access path 8 of said bogie, which makes it possible to reach gripping means of the contact disk 23 provided on the contact disk 13 of the electric current return device, the gripping means of the contact disk 23 making it possible to disassemble the contact disk from the electric current return device. 2013248232 18 Nov 2016 13

This alternative disassembly method further comprises a step for disassembling the brush 15, optionally securely linked to the brush holder 14, that is followed by a step in which said brush is separated from the brush holder.

Lastly, the invention pertains to an alternative method for assembling an 5 electric current return device of a bogie comprising a first step for bringing a contact disk 13 of the electric current return device through a frontal access path 8 followed by a step for assembling said contact disk on the brush of the electric current return device.

This alternative assembly method further comprises a step for assembling the 10 brush 15 on a support of the electric current return device, prior to the step for assembling the contact disk, said assembly step of the brush optionally being preceded by a step in which said brush is secured to the brush holder.

It is of course understood that the present invention is in no way limited to the embodiments above and that modifications may be made thereto without going 15 beyond the scope of the appended claims.

Claims

1. An electric current return device arranged to be enclosed in a railway vehicle bogie provided with at least one axle supporting a wheel on each of its ends, each wheel comprising a hub, a front face and a connected face, each connected face being linked to one end of said axle, said device comprising: a) at least one contact disk comprising at least one conductive material, b) at least one brush comprising at least one conductive material, in contact with said contact disk, c) a support comprising at least one insulating material d) a fastening means comprising at least one conductive material bound to said support and arranged to secure said support to a railway vehicle bogie, to which said axle is fastened, said support being provided to support said contact disk, situated on the side opposite the wheel, and allow said contact disk to be joined or not to be joined to said conductive fastening means, e) a connecting piece comprising at least one conductive material and arranged to securely link said brush to said front face of the wheel, said brush optionally being securely linked to a brush holder, wherein said support includes a support cavity arranged to house said contact disk, and wherein said conductive connection piece is an enclosure defining a cavity including a first and a second cavity part, said cavity of the enclosure being arranged to be closed on one side by said frontal face of said wheel and on the other side by said brush or by said brush holder, said first cavity part being arranged to house said brush or said brush and said brush holder, said second cavity part being destined to receive an area of wear dust retention.

2. The electric current return device according to claim 1, wherein the brush, or optionally the brush holder, comprises gripping means.

3. The electric current return device according to claim 1 or claim 2, wherein the contact disk comprises gripping means.

4. The electric current return device according to any one of claims 1 to 3, wherein said fastening means are mounted in an outer casing comprising at least one rigid insulating material.

5. The electric current return device according to claim 4, wherein said outer casing comprises connecting means with said contact disk, arranged to secure or not secure said contact disk to said outer casing.

6. The electric current return device according to claim 4 or 5, wherein said means for connecting to the outer casing is a projection arranged to pass through an orifice present on said support.

7. The electric current return device according to any one of the preceding claims, wherein said brush is securely linked to said brush holder by a lug fastening system.

8. The electric current return device according to any one of the preceding claims, wherein said dust retaining area is a double-baffle system.

9. A method for disassembling an electric current return device according to any one of claims 1 to 8, enclosed in a bogie comprising a disassembling of a brush of the electric current return device, wherein said disassembling of said brush, and possibly of brush holder, is realized using a gripping means provided on said brush or on said brush holder and accessible from said frontal way, and wherein said brush is disassembled from the first cavity part of the enclosure of said connection piece which houses and stabilizes said brush and said brush holder

10. The method for disassembling an electric current return device enclosed in a bogie according to claim 9, wherein the brush is further separated from its brush holder.

11. The method for disassembling an electric current return device enclosed in a bogie according to claim 9 or 10, further comprising a step in which the contact disk is disassembled using gripping means of the contact disk.

12. A method for assembling an electric current return device according to any one of claims 1 to 8, enclosed in a bogie comprising a mounting of a brush on a contact disk, wherein said mounting of said brush, and possibly of the brush holder, is realized by said frontal way using a gripping means provided on said brush or on said brush holder, and wherein said brush is mounted in the first cavity part of the enclosure of said connection piece which houses and stabilizes said brush and said brush holder.

13. The method for assembling an electric current return device in a bogie according to claim 12, wherein the brush is secured to the brush holder before said assembly step.

14. The method for assembling an electric current return device in a bogie according to claim 12 or claim 13, further comprising a step for assembling a contact disk on the support using gripping means of the contact disk.