DRIVE UNIT FOR A RAIL VEHICLE, AND HOLLOW SHAFT FOR SUCH A

Description

[0001] The invention relates to a drive unit for a rail vehicle comprising a drive motor, a wheelset transmission, and a connecting coupling for transmitting drive torque to a wheelset shaft. The wheelset transmission is connected to the drive motor to form a motor-transmission unit and has a hollow shaft as a transmission hub for a gear of the wheelset transmission. Furthermore, the invention relates to a hollow shaft for such a drive unit.

[0002] Drive units for rail vehicles are known, for example, from DE 19719746 C1 .The drive unit described therein, consisting of a motor and axle box, supports its weight via three suspensions on the bogie frame. The connecting coupling for transmitting the drive torque to the axle is designed as a separate hollow coupling shaft with two curved-tooth connections. The hollow transmission shaft, which carries the output gear of the axle box, is connected to an external gear. This gear meshes with the first internally toothed coupling sleeve of the separate hollow coupling shaft. The torque is transmitted to an external gear on the axle box via another, also internally toothed coupling sleeve on the other side of the hollow coupling shaft.

[0003] Furthermore, drive units are known in which rubber package couplings are used as connecting couplings.

[0004] A disadvantage of the drive units known to date is that they all feature connecting couplings, which require a lot of installation space. This poses a significant limitation in the design of the drive unit and the bogie.

[0005] The object of the invention is now to further develop the drive unit so that less installation space is required.

[0006] The object is achieved by a drive unit according to claim 1. Further advantageous features are mentioned in the dependent claims.

[0007] According to the invention, the drive unit is characterized in that the connecting coupling is designed as a toothed coupling, such that an internally toothed coupling sleeve, which is rigidly connected or formed in one piece with the hollow shaft, and an externally toothed output hub, which can be rigidly connected to a wheelset shaft, are in engagement via a toothing, so that the drive torque can be transmitted via it, and that a separate support element is present which supports part of the weight of the motor-gearbox unit outside the toothing on the output hub.

[0008] A key advantage of the inventive design is that, due to the one-piece or rigidly connected design of the hollow shaft of the transmission with the internally toothed coupling sleeve and the support via a support element on the wheelset shaft, the connecting coupling requires significantly less installation space than previously known solutions. A further advantage is that the functions of weight support and torque transmission are performed by separate components in the connecting coupling. This makes it easy to replace the separate support element when it becomes worn, without affecting the toothing of the connecting coupling.

[0009] In particular, the separate support element can be made of a different material than the internally toothed coupling sleeve. The respective material can thus be better optimized for the different tasks.

[0010] The support element is preferably designed as a ring. Alternatively, it can also be constructed from several individual segments, in particular ring segments.

[0011] To reduce friction between the output hub and the support element and to enable deflection of the connecting coupling, it is advantageous to design the support element with an arcuate contact surface with the output hub. Alternatively or additionally, it is advantageous to design the support surface on the output hub that is in contact with the support element in an arcuate shape.

[0012] The connecting coupling preferably has a cover that is rigidly connected to the coupling sleeve and closes off the connecting coupling. In particular, a seal to the wheelset shaft is provided on the cover. The rigid connection can be implemented, for example, via screw connections. Centering devices should be provided on the cover and the coupling sleeve.

[0013] In a particularly preferred embodiment, the lid carries the separate support element.

[0014] In another preferred embodiment, the coupling sleeve has a region that carries the separate support element, wherein this region is arranged outside the toothing. In particular, in this embodiment, an additional internal toothing can be provided on the cover, which engages with an additional external toothing present on the output hub. This allows the transmission of the drive torque to be distributed across two toothings. The separate support element is thus arranged between the two toothings. The outer diameter of the additional external toothing on the output hub should preferably be smaller than the inner diameter of the support element. This allows the support element to be removed over the additional external toothing for replacement without the output hub having to be pulled off the wheelset shaft.

[0015] Advantageously, the internal gearing of the coupling sleeve and the external gearing of the output hub and / or the further internal gearing of the cover and the further external gearing are curved. This design makes the connecting coupling a so-called curved-tooth coupling and can therefore compensate for displacements and deflections.

[0016] In addition to the support on the wheelset axle via the support element in the connecting coupling, the drive unit preferably has only two connections on the drive side of the motor-gearbox unit, which are intended to attach the drive unit to a bogie frame of the rail vehicle. Since only two additional connections are required to support the weight, further installation space is saved.

[0017] The design according to the invention is applicable to drive units with single-stage or two-stage gear sets and to both spur gears and bevel gears.

[0018] The hollow shaft for a drive unit according to the invention is characterized in that it forms the gear hub for receiving a gear of a wheelset transmission and is rigidly connected or designed as a single piece with an internally toothed coupling sleeve, wherein the internal toothing is suitable for transmitting drive torque in engagement with an externally toothed output hub on a wheelset shaft.

[0019] The rigidly connected or one-piece design of the hollow shaft creates an integral component that encompasses both the gear hub of the final drive and the coupling sleeve of the connecting coupling. This allows for a very space-saving drive unit design. The rigid connection can be achieved, for example, by screwing.

[0020] In particular, the hollow shaft can have an area on the coupling sleeve that can carry a separate support element that can transfer part of the weight of the drive unit to the wheelset shaft.

[0021] Further advantageous features of the invention are explained using exemplary embodiments with reference to the drawings. Fig. 1 schematic representation of a drive unit according to the invention Fig.2 Section of the connecting coupling Fig.3a Detailed view of the connecting coupling Fig.3b further design of the connecting coupling in detail

[0022] The Fig.1 shows a drive unit according to the invention for a rail vehicle, comprising the drive motor 1, the gear set 4 including the hollow shaft 3 with its gear hub 3.1, as well as the connecting coupling formed by the coupling sleeve 3.2 of the hollow shaft and the cover 3.3, as well as the output hub (not visible here). Also shown are the axis line of the input 30 and the axis line of the output 40. The hollow shaft 30 is arranged concentrically to the axis line of the output 40.

[0023] This example shows a single-stage spur gear train. The invention can also be advantageously used in two-stage or bevel gear train designs.

[0024] The drive unit is attached to the bogie frame 20 only via the two connections 21 and 22 and is additionally supported by the wheelset axle 2 of the rail vehicle. The bogie frame 20 and the wheelset axle 2 are not part of the drive unit.

[0025] Fig.2 shows a cross-sectional view of the connecting coupling. The output hub 11 is pressed onto the wheelset shaft 2 and is thus rigidly and non-rotatably connected to it. The output hub 11 has external gearing 11.1 and a separate support area 11.3.

[0026] Also visible is the hollow shaft 3, which includes a coupling sleeve 3.2 with internal gearing 3.2a. This internal gearing 3.2a engages with the external gearing 11.1, allowing the drive torque to be transmitted from the hollow shaft 3 to the wheelset shaft 2.

[0027] The coupling sleeve 3.2 is integrally formed with the gear hub 3.1, which carries the gear 7. Here, the gear 7 is the large gear of the final drive. It can, for example, be pressed onto the gear hub 3.1 or attached to it via a flange connection. Bearings 5 ​​and 6 support the hollow shaft 3 concentrically with the final drive shaft 2 in the gear housing (not shown).

[0028] Furthermore, a cover 3.3 is provided, which closes off the connecting coupling—formed by the coupling sleeve 3.2 and the output hub 11. Not shown is the seal between cover 3.3 and the wheelset shaft 2. The cover 3 carries the separate support element 12, which supports part of the weight of the drive unit on the wheelset shaft 2. It is clearly visible that the support element 12 can be easily removed in the event of wear after the rail wheels (not shown) have been removed from the wheelset shaft. The output hub 11 does not need to be removed from the wheelset shaft for this purpose.

[0029] For all embodiments according to the invention, the support element can be designed as a one-piece ring or as multi-piece segments, in particular also as multi-piece ring segments.

[0030] Due to the curved design of the toothing 3.2a, 11.1 and the curved contact surface of the support element 12, the connecting coupling is a so-called curved tooth coupling and can compensate for axial and angular displacements of the wheelset shaft or deflection.

[0031] The Fig.3a und 3b show variants for the design of the connecting coupling in detail. A first variant is shown in Fig.3a and corresponds to the Fig.2 described design. The cover 3.3 is rigidly connected to the coupling sleeve 3.2 via the screw connection 10. Also visible is the centering collar on the cover 3.3, which engages with a similar centering collar on the coupling sleeve 3.2.

[0032] The support element 12 is supported by the cover. In the illustrated embodiment, both the contact surface of the support element 12 with the output hub and the contact surface of the support area 11.3 of the output hub are curved to enable optimal mobility in the support.

[0033] Fig.3b represents another variant. Here, the support element 12 is carried by the coupling sleeve 3.2. The toothing 3.2a, 11.1 is somewhat shorter. The cover 3.3 is rigidly screwed to the coupling sleeve 3.2. The centering collar can also be seen, which here also serves to secure the separate support element 12.

[0034] Another internal toothing (3.3a) is incorporated into the cover (3.3), which meshes with another external toothing (11.2) on the output hub. This allows the drive torque to be transmitted to the wheelset shaft (2) evenly distributed across both toothings.

[0035] The support element 12 is located between the two gear teeth. One or both gear teeth are curved. The contact surfaces on the support element 12 and the support area 11.3 are also curved. This allows axial and angular displacements of the wheelset shaft 2 or deflections to be compensated.

[0036] The support element 12 has a larger inner diameter than the outer diameter of the additional external gearing 11.2. This allows the support element 12 to be removed without having to remove the output hub 11 from the wheelset shaft 2. Bezugszeichenliste

[0037] 1Drive motor 2Wheelset axle 3Hollow shaft 3.1Gear hub 3.2Coupling sleeve 3.2aInternal gearing 3.3Cover 3.3aFurther internal gearing 4Wheelset transmission 5, 6Hollow shaft bearing 7Gear 10Screw connection 11Output hub 11.1External toothing 11.2Further external toothing 11.3Support area 12Support element 20Bogie frame 21First connection 22Second connection 30Drive axle line 40Output axle line

Claims

1. Drive unit for a rail vehicle, comprising a drive motor (1), a wheelset transmission (4) and a connecting coupling for transmitting drive torque to a wheelset shaft (2), wherein the wheelset transmission is connected to the drive motor to form a motor / transmission unit and has a hollow shaft (3) as transmission hub (3.1) for a gearwheel (7) of the wheelset transmission, wherein the connecting coupling is designed as a tooth coupling in such a way that an internally toothed coupling sleeve (3.2), which is designed to be connected rigidly to the hollow shaft (3) or is formed in one piece therewith, and an externally toothed output hub (11), which can be connected rigidly to a wheelset shaft (2), are in engagement via a toothing (3.2a, 11.1), so that the drive torque can be transmitted via this, characterized in that provision is made of a separate supporting element (12) which supports some of the weight force of the motor / transmission unit outside the toothing (3.2a, 11.1) on the output hub (11).

2. Drive unit according to Claim 1, characterized in that the connecting coupling has a cover (3.3) which is connected rigidly to the coupling sleeve (3.2) and which has a further internal toothing (3.3a) which engages into a further external toothing (11.2) on the output hub (11) for transmitting the drive torque.

3. Drive unit according to Claim 1 or 2, characterized in that the coupling sleeve (3.2) has a region which carries the separate supporting element (12).

4. Drive unit according to Claim 1 or 2, characterized in that the connecting coupling has a cover (3.3) which is connected rigidly to the coupling sleeve (3.2) and which carries the separate supporting element (12).

5. Drive unit according to one of the preceding claims, characterized in that the toothings (3.2a, 11.1) and / or the further toothings (3.3a, 11.2) are of arcuate form and the connecting coupling is thus a curved tooth coupling.

6. Drive unit according to one of the preceding claims, characterized in that, for accommodating the weight force, besides the support on the wheelset shaft (2) via the supporting element (12) in the connecting coupling, the drive unit otherwise has just two attachments (21, 22) on a bogie frame (20) on the drive side of the motor / transmission unit.

7. Drive unit according to one of the preceding claims, characterized in that the supporting element (12) has an arcuate contact surface in relation to the output hub (11).