Drive unit for a rail vehicle wheel set

Abstract

A drive unit for driving at least one wheel drive shaft, in particular of a wheelset axle, in particular a cross-drive for use in rail vehicles with a driving engine and a transmission assembly coupled thereto. The output of the transmission assembly is formed by a hollow shaft which is coupled via an articulated coupling to the wheel drive shaft, in particular the wheelset axle. A first braking subsystem and a second braking subsystem are embodied as disk brake systems, each comprising at least one brake disk. An attachment flange of the brake disk of one braking subsystem is embodied in integral fashion with the hollow shaft. Placement of the braking subsystems along the hollow shaft is disclosed.

Description

BACKGROUND OF THE INVENTION [0001] The invention relates to a drive unit for driving at least one wheel drive shaft, in particular of a wheelset axle, for rail vehicles. [0002] Such a drive unit has been disclosed by DE 4 137 233 A. [0003] The solution described there has, however, the disadvantage that the necessary installation space is relatively large, which has disadvantageous effects particularly in vehicles of the low-platform type. The fabrication and mounting are also relatively complex. [0004] A similar design of a drive unit has been disclosed by U.S. Pat. No. 4,042,071, see column 1, lines 12-14 in this document. [0005] Drive units for rail vehicles, in particular having an integrated cross-drive, are known in a multiplicity of embodiments. These comprise a driving engine which is coupled to a transmission assembly. The drive of the transmission assembly is formed by a hollow shaft which is coupled via an articulated coupling to the wheel drive shaft, in particular the w...

AI Technical Summary

Benefits of technology

[0003] The solution described there has, however, the disadvantage that the necessary installation space is relatively large, which has disadvantageous effects particularly in vehicles of the low-platform type. The fabrication and mounting are also relatively complex.

[0004] A similar design of a drive unit has been disclosed by U.S. Pat. No. 4,042,071, see column 1, lines 12-14 in this document.

[0005] Drive units for rail vehicles, in particular having an integrated cross-drive, are known in a multiplicity of embodiments. These comprise a driving engine which is coupled to a transmission assembly. The drive of the transmission assembly is formed by a hollow shaft which is coupled via an articulated coupling to the wheel drive shaft, in particular the wheelset axle, in order to compensate the relative movements between the wheelset axle and cross-drive. The driving engine is arranged here in the direct spatial vicinity of the transmission assembly, preferably both—driving engine and transmission assembly—are connected to one another by flanges in the region of their housings. As a result of this measure, only one radial bearing is necessary for the driving engine and a corresponding end shield. The coupling of the drive shaft of the driving engine to the transmission input shaft is carried out by means of what is referred to as a rotationally rigid and radially rigid diaphragm coupling. The transmission assembly itself is usually embodied in two stages or in a single stage with an intermediate wheel. The output gearwheel is seated here on the hollow shaft, said output gearwheel being either coupled fixed in terms of rotation to the hollow shaft or else forming one physical unit with said hollow shaft. The physical unit composed of the driving engine and transmission assembly, which is also referred to as an integrated cross-drive, is attached only at three points in the bogey frame with primary suspension. If necessary, a braking system is assigned to the drive unit, the brake disk being arranged on the hollow shaft. The activation elements are arranged in the housing of the transmission assembly. The disadvantage of the previous solution is that, on the one hand, the overall costs for the structural implementation and fabrication are relatively high. Furthermore, in particular for embodiments which are to be used in low-platform vehicles, the available radial and axial installation space is considerably reduced as a result of wheel diameters which are becoming ever smaller while at the same time drive hollow shaft internal diameters are becoming larger owing to the softer suspensions. There is thus no longer sufficient installation space available to arrange the braking system in this region in order to achieve sufficient braking deceleration. Solutions for this are to arrange the braking system at another location or else to do without conventional mechanical braking systems and use other braking systems, for example electrical braking systems, which are however more costly. SUMMARY OF THE INVENTION

[0006] The invention has therefore been based on the object of developing a drive unit for a wheel drive shaft, in particular a wheelset axle, in particular for the use of rail vehicles of the type mentioned at the beginning, in such a way that sufficient braking deceleration is achieved with simple means and also with an axial and radial installation space which is becoming smaller and smaller. The structural solution is intended here to be defined by a simple embodiment, cost-effective fabrication and mounting. Furthermore, the solution according to the invention is to be applicable in particular for vehicles of the low-platform type.

[0007] According to the invention, the drive unit for driving at least one wheel drive shaft, in particular of a wheelset axle, comprises a cross-drive with a driving engine and a transmission assembly which is coupled thereto. The output of the transmission assembly is embodied as a hollow shaft and is connected to the wheel drive shaft or the wheelset axle via a coupling, in particular an articulated coupling. The braking system comprises two braking subsystems by means of which the entirety of the braking force necessary can be generated by activating two braking subsystems.

[0008] The solution according to the invention provides the advantage that as a result of the distribution between a plurality of braking systems said braking systems can, in their entirety, be kept respectively smaller in terms of their dimensions in the radial and axial directions and the installation space available can thus be used to an optimum degree.

Problems solved by technology

The solution described there has, however, the disadvantage that the necessary installation space is relatively large, which has disadvantageous effects particularly in vehicles of the low-platform type.

The fabrication and mounting are also relatively complex.

The disadvantage of the previous solution is that, on the one hand, the overall costs for the structural implementation and fabrication are relatively high.

There is thus no longer sufficient installation space available to arrange the braking system in this region in order to achieve sufficient braking deceleration.

Solutions for this are to arrange the braking system at another location or else to do without conventional mechanical braking systems and use other braking systems, for example electrical braking systems, which are however more costly.

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