Bogie and associated railway vehicle

Abstract

Bogie and associated railway vehicle A motor bogie for a railway vehicle comprises a chassis and railway wheels (14). At least one of the railway wheels (14) is a driving railway wheel (14) carried by a wheel hub (24) guided in rotation relative to the chassis by means of a rotation guide assembly (17) comprising two rolling bearings (50, 52) and coupled to a traction motor (16) by means of a gear transmission comprising an output gear (18) having a driving toothed wheel (34) meshing with a driven toothed wheel (36) which is mounted on the wheel hub (24) and which comprises a toothed ring (38) and a ring carrier (40) axially offset from each other. The ring carrier (40) is closer to the driving railway wheel (14) than the toothed ring (38). Figure for abstract: Figure 3

Description

Title of the invention: Bogie and associated railway vehicle

[0001] The present invention relates to a bogie for a railway vehicle, the bogie comprising a chassis on which a body of the railway vehicle rests and railway wheels for supporting and guiding the chassis along a railway track.

[0002] In the field of railway vehicles, and in particular railway vehicles intended for intra-urban transport such as, for example, multi-articulated trams, it is known to install bogies capable of allowing only a slight angular movement around a vertical axis between the chassis of these bogies and the bodies of the railway vehicle carried by these bogies, to facilitate the passage of curves, the main rotations taking place between the different bodies. In this case, we speak of a non-pivoting bogie.

[0003] However, if the railway vehicle is intended to operate on railway tracks with reduced radii of curvature, the concept of a multi-articulated tramway is not suitable and it is desirable to maximize the permitted rotation angle between the bogie chassis and the body of the railway vehicle, to approach a more conventional design. In this case, we speak of a pivoting bogie.

[0004] Furthermore, in a railway vehicle intended for intra-urban transport, it is advantageous to install a body having a lowered floor, that is to say a floor fairly close to the ground and, preferably, extending substantially at the same level in the body, and to arrange in said body wide circulation corridors. This facilitates the movement of passengers in the railway vehicle and access to the railway vehicle from the outside, in particular for passengers who have difficulty moving around.

[0005] However, such a design of a low-floor railway vehicle reduces the free volume under the body. A bogie carrying a body of such a railway vehicle must therefore be adapted in order to reduce its size.

[0006] An object of the invention is to provide a railway vehicle bogie adapted to receive a lowered floor body while allowing a large rotation angle between the chassis of the bogie and the vehicle body.

[0007] Thus, the invention relates to a bogie of the aforementioned type, in which at least one of the railway wheels is a driving railway wheel carried by a wheel hub guided in rotation relative to the chassis by means of a rotation guide assembly comprising two rolling bearings and coupled to a traction motor by means of a gear transmission comprising an output gear having a driving toothed wheel meshing with a driven toothed wheel which is mounted on the wheel hub and which comprises a toothed crown and a carrier. crowns axially offset from each other, the crown carrier being closer to the driving railway wheel than the toothed crown.

[0008] According to particular embodiments of the invention, the bogie has one or more of the following characteristics, taken independently or in any technically feasible combination:

[0009] - one of the rolling bearings of the rotating guide assembly is surrounded by the toothed crown of the driven toothed wheel, in particular is arranged along the wheel hub in a housing delimited radially by the toothed crown of the driven toothed wheel;

[0010] - one of the rolling bearings is located along the wheel hub between the wheel railway and the driven gear wheel, the other rolling bearing being located on the side of the driven gear wheel opposite the railway wheel;

[0011] - the wheel hub is rotatably mounted on the chassis by means of a box axle, the gear transmission(s) being housed inside the axle box;

[0012] - the axle box comprises an inclined internal side wall, and more particularly at an angle of inclination, measured relative to the longitudinal direction X-X', greater than 10°;

[0013] - the gear transmission comprises an input gear interposed between a output shaft of the traction motor and the output gear, the distance taken in the transverse direction Y-Y' between the input gear and the railway wheel being greater than the distance between the output gear and the railway wheel;

[0014] - the motor is located outside a space between the railway wheels;

[0015] - the bogie is configured to support a railway vehicle body having a floor passing through the space delimited between the railway wheels, allowing the body to pivot relative to the bogie around a substantially vertical pivot axis;

[0016] - the bogie is configured to allow rotation of the body relative to the chassis around the pivot axis with a maximum pivot angle equal to or greater than 10°, in particular equal to or greater than 12.5°, for a floor extending between the railway wheels having a width equal to or greater than 450 mm, in particular equal to or greater than 500 mm.

[0017] The invention also relates to a railway vehicle comprising at least one bogie and a vehicle body carried by said bogie, the body comprising a lowered floor.

[0018] The invention will be better understood on reading the following description, given by way of example and with reference to the appended drawings, among which:

[0019] - [Fig.l] [Fig.l] is a perspective view of a bogie;

[0020] - [Fig.2] [Fig.2] is a schematic top view of the bogie of [Fig.l], the body being pivoted relative to the chassis; and

[0021] - [Fig.3] [Fig.3] is a sectional view along line AA of the bogie of [Fig.l], illustrating the mounting of a railway wheel in the environment of the bogie transmission.

[0022] [Fig.l] represents a railway vehicle bogie 10 intended to equip a railway vehicle. The railway vehicle is for example a railway vehicle intended for intra-urban transport such as a tramway.

[0023] The bogie 10 is provided to support and guide the railway vehicle along a railway track, in particular a railway track formed of two parallel lines of rails (not shown).

[0024] In the following, the orientations are indicated with respect to a longitudinal direction X-X' corresponding to the ordinary direction of circulation of the railway vehicle along the railway track, a transverse direction Y-Y' orthogonal to the longitudinal direction X-X', extending in a horizontal plane in ordinary operation of the railway vehicle, and an elevation direction Z-Z' substantially orthogonal to the transverse direction Y-Y' and to the longitudinal direction X-X'.

[0025] The bogie 10 comprises a chassis 12 and railway wheels 14.

[0026] The chassis 12 is configured to support a body (not shown) delimiting a compartment for passengers, and the railway wheels 14 are configured to support and guide the chassis 12 along the railway track.

[0027] Each railway wheel 14 is rotatably mounted on the chassis 12 around a wheel axle.

[0028] The railway wheels 14 are associated in pairs, thus forming two axles extending in the transverse direction Y-Y'.

[0029] The railway wheels 14 define between them a space E, shown in [Fig.l]. The space E extends between the railway wheels 14 in the transverse direction Y-Y'.

[0030] The bogie 10 is configured to support a body (not shown) comprising a lowered floor 15.

[0031] When the body rests on the chassis 12 of the bogie 10, the area of ​​the floor 15 located above the bogie 10 is for example located at a height lower than the diameter of the railway wheels 14, the height being measured in the elevation direction Z-Z' and relative to the tops of the rails of the railway track.

[0032] In the area of ​​the floor 15 located above the bogie 10, the floor 15 of said body passes into the space E delimited transversely between the railway wheels 14 of an axle.

[0033] The area of ​​the floor 15 located above the bogie 10 extends for example to a height substantially equal to or less than 480 mm, in particular equal to or less than 450 mm, the height being measured in the elevation direction Z-Z' and relative to the tops of the rails of the railway track.

[0034] Preferably, the floor 15 extends substantially at the same level over the entire body, including above the bogie 10.

[0035] In the area of ​​the floor 15 located above the bogie 10 and extending between the railway wheels 14, advantageously has a width equal to or greater than 450 mm, in particular equal to or greater than 500 mm, the width being measured in the transverse direction Y-Y'.

[0036] Such a width of the floor 15 of said box facilitates the movement of passengers in the corridor.

[0037] The bogie 10 is a pivoting bogie. The bogie 10 is configured to support the railway vehicle body by allowing pivoting of the railway vehicle body relative to the chassis 12 about a pivot axis substantially parallel to the elevation direction Z-Z'. as illustrated in [Fig.2].

[0038] The bogie 10 comprises for example an articulation 13 which is configured so that the body rests on the chassis 12 by means of this articulation, allowing the body to pivot relative to the chassis 12.

[0039] Due to the passage of the floor 15 of the body in the space E delimited between the railway wheels 14, the floor 15 of the body can limit the maximum pivot angle [3 of the body relative to the bogie 10.

[0040] The pivot angle [3 of the body relative to the bogie 10 is measured relative to the longitudinal direction X-X'.

[0041] The arrangement of the transmission near the railway wheels 14 is designed so as to allow a satisfactory pivoting angle of the body relative to the bogey 10.

[0042] The bogie 10 is preferably configured such that the maximum permitted pivot angle [3 of the body relative to the chassis 12 is for example equal to or greater than 10°, in particular equal to or greater than 12.5°.

[0043] The bogie 10 is a motor bogie. The bogie 10 comprises at least one traction motor 16, each traction motor 16 is coupled to at least one of the railway wheels 14 for driving this railway wheel 14 in rotation.

[0044] Each railway wheel 14 coupled to a traction motor 16 is a driving railway wheel 14.

[0045] In the example illustrated in [Fig.l], the bogie 10 comprises a respective traction motor 16 associated with each railway wheel 14 for driving this railway wheel 14 in rotation. Each motor 16 is associated with a single wheel among the wheels railways 14. Each motor 16 drives rotation only the associated railway wheel 14.

[0046] Advantageously, each motor 16 is located outside the space E located between the railway wheels 14 in the transverse direction Y-Y'. Thus, each motor 16 does not occupy the space E to leave more space for the passage of the floor 15 of the body supported by the bogie 10.

[0047] Each driving railway wheel 14 is for example rotatably mounted on the chassis 12 by means of an axle box 26 which integrates the transmission elements. The bogie 10 preferably comprises a respective axle box 26 associated with each driving railway wheel 14.

[0048] In an exemplary embodiment, the axle box 26 associated with each driving railway wheel 14 is located in the space E delimited transversely between the railway wheels 14.

[0049] The mounting of a driving railway wheel 14 and its coupling to the associated traction motor 16 are described below with reference to [Fig. 3] which illustrates a sectional view taken along AA in [Fig. 1], of an axle box 26 associated with a railway wheel 14 and a traction motor 16.

[0050] Each driving railway wheel 14 is carried by a wheel hub 24 which is guided in rotation relative to the chassis 12 by means of a rotation guide assembly 17 interposed between the wheel hub 24 carrying the railway wheel 14 and the associated axle box 26 to allow rotation of the railway wheel 14 around its axis.

[0051] The rotational guide assembly 17 comprises two rolling bearings 50, 52, each rolling bearing 50, 52 being interposed between the wheel hub 24 and the axle box 26.

[0052] The rotational guide assembly 17 comprises, for example, a first rolling bearing 50 and a second rolling bearing 52 spaced from each other along the wheel hub 24.

[0053] The axle box 26 is hollow. It has an outer side wall and an inner side wall spaced transversely from each other, the inner side wall being closer to the median longitudinal plane of the bogie 10 than the outer side wall. The outer side wall is closer to the railway wheel 14 than the inner side wall.

[0054] Each rolling bearing is for example interposed between the wheel hub 24 and a respective side wall of the axle box 26 among the inner side wall and the outer side wall.

[0055] Each railway wheel 14 is rotatably coupled to an output shaft of the associated traction motor 16 via a gear transmission.

[0056] The gear transmission is configured to transmit motion from the output shaft of the traction motor 16 to the wheel hub 24 carrying the railway wheel 14. The gear transmission is preferably housed within the axle box 26.

[0057] Advantageously, the gear transmission is configured for a ratio between the rotational speed of the output shaft of the traction motor 16 and the rotational speed of the wheel hub 24 carrying the railway wheel 14 which is strictly greater than 1. The gear transmission thus forms a speed reducer.

[0058] The gear transmission comprises an output gear 18 having a driving gear 34 meshing with a driven gear 36, which is for example keyed to the wheel hub carrying the railway wheel 14.

[0059] The driven gear wheel 36 is coaxial with the rail wheel 14 and the wheel hub 24, on which it is mounted.

[0060] The driven gear wheel 36 comprises a toothed crown 38 carrying the teeth of the driven gear wheel 36, a crown carrier 40, and a connecting portion 42 connecting the toothed crown 38 to the crown carrier 40.

[0061] The crown carrier 40 is engaged on the wheel hub 24 in such a way that the driven toothed wheel 36 is rotationally connected to the wheel hub 24.

[0062] The crown carrier 40 and the toothed crown 38 are axially offset relative to each other. The crown carrier 40 is offset relative to the toothed crown 38 along the wheel hub 24.

[0063] The connecting part 42 has, for example, a generally conical shape widening from the crown carrier 40 towards the toothed crown 38.

[0064] Due to the relative axial offset of the toothed crown 38 and the crown carrier 40, the driven toothed wheel 36 defines a housing 43 which is delimited radially by the toothed crown 38.

[0065] The driven gear wheel 36 is for example mounted on the wheel hub 24 in such a way that the crown carrier 40 is closer to the railway wheel 14 than the crown gear 38. The housing 43 is located on the side of the driven gear wheel 36 opposite the railway wheel 14.

[0066] Preferably, the output gear 18 is a parallel axis gear, the axis of the driving gear 34 being parallel to the axis of the driven gear 36.

[0067] Preferably, the driven gear 36 is located along the wheel hub 24 between the first rolling bearing 50 and the second rolling bearing 52.

[0068] The first rolling bearing 50 is located along the wheel hub 24 between the rail wheel 14 and the driven gear wheel 36.

[0069] The second rolling bearing 52 is located along the wheel hub 24 on the side of the driven gear wheel 36 opposite the rail wheel 14.

[0070] The relative axial offset of the crown gear 38 and the crown carrier 40 of the driven gear wheel 36 wedged on the wheel hub 24 allows an axially compact arrangement of the rotation guide assembly 17 and the driven gear wheel 36 along the wheel hub 24, while allowing the meshing of the driven gear wheel 36 with the driving gear wheel 34 of the output gear 18.

[0071] In particular, the crown carrier 40 may be positioned axially closer to the railway wheel 14 than the toothed crown 38, and the second rolling bearing 52 may be brought closer to the railway wheel 14 relative to the case where the crown carrier 40 is not axially offset relative to the toothed crown 38.

[0072] The second rolling bearing 52 is arranged along the wheel hub 24 in such a way that it is at least partly surrounded by the toothed ring 38 of the driven toothed wheel 36.

[0073] As can be seen in [Fig. 3], the second rolling bearing 52 is surrounded by the toothed crown 38 of the driven toothed wheel 36.

[0074] In other words, the second rolling bearing 52 is arranged along the wheel hub 24 in the housing 43 delimited radially by the toothed crown 38, and in particular in the vertical plane formed by the toothed crown 38. It is thus possible to limit the size of the output gear 18 located on the internal side of the railway wheel 14, to allow significant angular movement of the body supported by the bogie, despite the presence of a lowered floor 15 passing between the railway wheels 14.

[0075] In particular, as illustrated in [Fig.3], the axle box 26 is for example provided with a decreasing width from a portion of the axle box 26 connected to the chassis towards a portion of the axle box 26 carrying the wheel hub 24.

[0076] The axle box 26 comprises an internal side wall 27 which can be inclined in such a way that it moves away transversely from the median vertical plane of the bogie 10 in a progressive manner when this internal side wall is traveled horizontally away from the pivot axis of the body relative to the bogie 10.

[0077] Advantageously, the internal side wall 27 of the axle box 26 is inclined at an angle of inclination a, measured relative to the longitudinal direction X-X', greater than 10°.

[0078] As illustrated in [Fig.2], the angle of inclination a of the internal side wall 27 of the axle box 26 is substantially equal to the maximum permitted pivot angle [3 of the body relative to the bogie 10. Such a bogie 10 makes it possible to authorize pivoting between the chassis 12 of the bogie and the body of the vehicle by an angle [3 greater than 10°, which allows the railway vehicle to operate on railway tracks with high curvatures (i.e. small radii of curvature).

[0079] The inclined internal side wall 27 of the axle box 26 offers the advantage of being able to maximize said rotation angle and of defining a corridor floor 15 of sufficient width to be able to allow the movement of passengers on said corridor.

[0080] Thanks to this small size, the bogie 10 is suitable for carrying a body with a lowered floor 15.

[0081] The invention is not limited to the exemplary embodiments and variants described above, other exemplary embodiments and other variants being conceivable.

[0082] In the illustrated embodiment, each of the railway wheels 14 is driven and associated with a dedicated traction motor.

[0083] Alternatively, only certain railway wheels 14 are driven. It is for example possible to provide that the two railway wheels 14 of the same pair are driven, the two railway wheels 14 of the other pair being non-driven.

[0084] In such an exemplary embodiment, the bogie 10 may comprise two traction motors 16.

[0085] Furthermore, the same traction motor 16 can be coupled to two driving railway wheels 14, these two driving railway wheels 14 being linked in rotation by a shaft, for example a shaft offset relative to the axis of the railway wheels 14.

[0086] Such a transmission shaft is for example housed in a spacer crosspiece 32 extending transversely between the axle boxes 26 of these railway wheels 14.

[0087] Furthermore, as illustrated in [Fig.3], the gear transmission further comprises an input gear 46 interposed between the output shaft of the traction motor 16 and the output gear 18.

[0088] The input gear 46 is for example a gear with parallel axes, the axes of rotation of the toothed wheels of this input gear 46 being parallel to each other, and, preferably, to those of the output gear 18.

[0089] The two gears 18, 46 together form a gear train 47 configured to transmit the rotation of the output shaft of the motor 16 to the wheel hub 24 carrying the railway wheel 14.

[0090] As illustrated in [Fig.3], the input gear 46 is offset towards the inside of the bogie 10 and the output gear 18 is offset towards the wheel 14.

[0091] In other words, the distance taken along the transverse direction Y-Y' between the input gear 46 and the railway wheel 14 is greater than the distance taken along the transverse direction Y-Y' between the output gear 18 and the railway wheel 14.

[0092] Similarly, the distance taken along the transverse direction Y-Y' between the input gear 46 and the railway wheel 14 is greater than the distance taken along the transverse direction Y-Y' between the second rolling bearing 52 and the railway wheel 14. The input gear 46 and the output gear 18 each have a ratio of reduction strictly greater than 1 and then form a first reduction stage and a second reduction stage.

[0093] Advantageously, the gear transmission makes it possible, in addition to adjusting the transmission ratio between the motor 16 and the railway wheel 14, to transmit the torque from the traction motor 16 to the railway wheel 14 without aligning the axes of the wheel hub 24 carrying the railway wheel 14 and of the output shaft of the traction motor 16 in the transverse direction Y-Y'. Thus, the traction motor 16 and the railway wheel 14 are offset in the longitudinal direction X-X' and / or the elevation direction Z-Z', which allows a compact arrangement reducing the lateral size of the bogie 10.

Claims

Claims

1. A motor bogie for a railway vehicle, comprising a chassis (12) and railway wheels (14), wherein at least one of the railway wheels (14) is a driving railway wheel (14) carried by a wheel hub (24) guided in rotation relative to the chassis (12) by means of a rotation guide assembly (17) comprising two rolling bearings (50, 52) and coupled to a traction motor (16) by means of a gear transmission comprising an output gear (18) having a driving toothed wheel (34) meshing with a driven toothed wheel (36) which is mounted on the wheel hub (24) and which comprises a toothed ring (38) and a ring carrier (40) axially offset relative to each other, the ring carrier (40) being closer to the driving railway wheel (14) than the ring toothed (38),the bogie being configured to support a railway vehicle body having a floor (15) passing through the space (E) delimited between the railway wheels (14), allowing the body to pivot relative to the bogie (10) around a substantially vertical pivot axis.,

2. Bogie according to claim 1, wherein one of the rolling bearings (52) of the rotational guide assembly (17) is surrounded by the toothed ring (38) of the driven toothed wheel (36), in particular is arranged along the wheel hub (24) in a housing (43) delimited radially by the toothed ring (38) of the driven toothed wheel (36).

3. A bogie according to any preceding claim, wherein one of the rolling bearings (50) is located along the wheel hub (24) between the rail wheel (14) and the driven gear wheel (36), the other rolling bearing (52) being located on the side of the driven gear wheel (36) opposite the rail wheel (14).

4. A bogie according to any preceding claim, wherein the wheel hub (24) is rotatably mounted on the chassis (12) via an axle box (26), the gear transmission(s) being housed inside the axle box (26).

5. A bogie according to claim 4, wherein the axle box (26) comprises an inclined inner side wall (27), and further particularly at an angle of inclination (a), measured relative to the longitudinal direction X-X', greater than 10°.

6. A bogie according to any preceding claim, wherein the gear transmission comprises an input gear (46) interposed between an output shaft of the traction motor (16) and the output gear (18), the distance taken in the transverse direction Y-Y' between the input gear (46) and the railway wheel (14) being greater than the distance between the output gear (18) and the railway wheel (14).

7. A bogie according to any preceding claim, wherein the motor (16) is located outside a space (E) between the railway wheels (14).

8. Bogie according to any one of the preceding claims, wherein the bogie (10) is configured to allow rotation of the body relative to the chassis (12) around the pivot axis with a maximum pivot angle (|3) equal to or greater than 10°, in particular equal to or greater than 12.5°, for a floor (15) extending between the railway wheels (14) having a width equal to or greater than 450 mm, in particular equal to or greater than 500 mm.

9. Bogie according to claim 4 taken alone or in combination with any one of claims 5 to 8, in which the axle box (26) associated with each driving railway wheel (14) is located in the space (E) delimited transversely between the railway wheels (14).

10. A railway vehicle comprising at least one bogie (10) according to one of the preceding claims, and a vehicle body carried by said bogie (10), the body comprising a lowered floor (15).

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