Axle drive for an electrically driven axle of a motor vehicle

Abstract

Axle drive (100; 200; 300) for an axle, preferably for an electrically driven axle, of a motor vehicle, for example a commercial vehicle, which has a basic module (100a; 200a, 300a) comprising: an axle differential (1), preferably an axle differential lockable with a transverse lock, and two wheel drive shafts (3a, 3b) driven by the axle differential (1); a drive shaft (2) arranged parallel to the wheel drive shafts (3a, 3b); a first intermediate shaft (101; 201; 301) arranged parallel to the wheel drive shafts (3a, 3b); a hollow shaft (102; 202; 302) arranged coaxially to the wheel drive shafts (3a, 3b); and at least a first transmission stage (110; 210; 310) and a second transmission stage (120; 220; 320) which are arranged for the driving connection of the drive shaft (2) to the axle differential (1) via the first intermediate shaft (101; 201; 301) and the hollow shaft (102; 202; 302), wherein the drive shaft (2) is connected to the first intermediate shaft (101; 201; 301) via the first transmission stage (110; 210; 310), the first intermediate shaft (101; 201; 301) is permanently connected to the hollow shaft (102; 202; 302) via the second transmission stage (120; 220; 320) or can be switchedly connected; and the first intermediate shaft (101; 201; 301) is arranged between the drive shaft (2) and the hollow shaft (102; 202; 302); and one of the wheel drive shafts (3a, 3b) is arranged at least partially inside the hollow shaft (102, 202, 302), characterized by a second intermediate shaft (103) arranged parallel to the wheel drive shafts (3a, 3b), serving as a countershaft, which is arranged on the opposite side of the hollow shaft (102) in relation to the first intermediate shaft (101) and which is connected to the axle differential (1) via a fourth transmission stage (140); and a third transmission stage (130) which is arranged to connect the hollow shaft (102) to the second intermediate shaft (103) for driving purposes.

Description

[0001] The present invention relates, inter alia, to an axle transmission and a transmission kit for an electrically driven axle of a motor vehicle, preferably a commercial vehicle.

[0002] First, with regard to the state of the art, reference should be made to the documents WO 2019 / 121 635 A1, DE 10 2016 002 592 A1 and DE 10 2015 101 042 A1.

[0003] Document WO 2019 / 121635 A1 describes an electric axle assembly comprising an electric motor with an output shaft. A two-stage gear train is coupled to the output shaft. The two-stage gear train includes two reduction gears that provide different gear ratios. A differential is also provided.

[0004] The document DE 10 2016 002 592 A1 discloses a transmission device for a vehicle, comprising a transmission structure and an electric drive for driving the vehicle, wherein the transmission structure is designed as a transmission module and is connected on the drive side to the drive drive.

[0005] The document DE 10 2015 101 042 A1 relates to an electrically driven axle for a motor vehicle, wherein two gear stages can be realized by means of the axle, and the axle has a single electric machine, at least one planetary gear, a differential gear, two output shafts for driving the road wheels of the motor vehicle assigned to the axle, and means for switching the gear stages.

[0006] Electric vehicles with electric drive and associated transmission design are known in the state of the art in a wide variety of designs.

[0007] For example, DE 10 2013 204 227 A1 discloses a drive train for a vehicle with an electric drive that can be coupled to at least a first gear ratio and a second gear ratio via a drive shaft. At least one shifting device for shifting the gear ratios is provided, wherein the shifting device comprises at least one positive shifting element and at least one frictional shifting element for performing power shifts. Each of the gear ratios can be shifted using the positive shifting element. At least one of the gear ratios can be shifted using both the positive shifting element and the frictional shifting element.

[0008] Modular systems can be used to construct a transmission for a motor vehicle. For example, DE 10 2016 002 592 A discloses a 1- or 2-speed transmission device for an electric vehicle with a modular design. The transmission device comprises a transmission structure and an electric drive for driving the vehicle. The transmission structure is designed as a transmission module and is directly connected to the drive side of the transmission.

[0009] The invention is based on the object of creating an alternative and / or improved transmission technology for an electrically powered motor vehicle. The object of the invention is, in particular, to provide a transmission technology for an electrically driven axle of a motor vehicle that enables a compact transmission arrangement and can be cost-effectively adapted to an entire fleet of motor vehicles of different power classes.

[0010] These objects are achieved by an axle drive having the features of the independent claim. Advantageous further developments are specified in the dependent claims and the description.

[0011] According to a first general aspect, the present disclosure relates to an axle drive for a driven axle of a motor vehicle, preferably for an electrically driven axle of a motor vehicle. The motor vehicle can be a commercial vehicle. The axle drive has a basic module comprising: an axle differential, two wheel drive shafts driven by the axle differential, a drive shaft arranged parallel to the wheel drive shafts, an intermediate shaft arranged parallel to the wheel drive shafts, which is referred to below as the first intermediate shaft, and a hollow shaft arranged coaxially to the wheel drive shafts. The wheel drive shafts are mounted in the wheel bearings and guided in the axle shaft gears of the axle differential, where they receive power via shaft-hub connections.The basic module further comprises at least a first gear ratio and a second gear ratio, which are arranged to drive the drive shaft to the axle differential via the first intermediate shaft and the hollow shaft. The power of a drive unit (power source) is thus transmitted to a hollow shaft during traction operation via the drive shaft and the intermediate shaft with the first two gear ratios. During overrun operation, a reverse power flow is possible. According to a highlighted embodiment, the drive unit that drives the drive shaft (during traction operation) is an electric machine, so that the axle is designed as an electrically driven axle. In the present case, an axle transmission is understood to mean a transmission arranged in the region of the axle.

[0012] The term "basic module" is intended to express that the above components and their arrangement represent basic building blocks that can be optionally supplemented with additional gear stages to create various axle drive variants. This can enable a high degree of modularity for the axle drive with corresponding economies of scale. Axle drives of different performance classes can be mass-produced based on this basic module with low development costs and low component and production costs. The selected components of the axle drive and their arrangement also enable a space-saving design of the axle drive and minimize the need for packaging.

[0013] The first intermediate shaft is located between the drive shaft and the hollow shaft. In other words, the distances between the first intermediate shaft and the parallel drive shaft and the parallel hollow shaft are smaller than the distance between the drive shaft and the hollow shaft. Furthermore, for a particularly compact design, one of the wheel drive shafts is at least partially located and / or runs radially inside the hollow shaft. The hollow shaft around the vehicle axle shafts enables a symmetrical system design and optimally utilizes the available installation space.

[0014] The term "first intermediate shaft" is used to better distinguish this intermediate shaft from another intermediate shaft that may be optionally provided. This additional intermediate shaft is referred to below as the second intermediate shaft or countershaft. The drive shaft is also referred to below as the input shaft. The gear ratios may also be referred to as transmission stages.

[0015] In other embodiments, the axle drive can have additional gear ratios or transmission stages. For ease of differentiation, these are referred to below as third, fourth, etc. gear ratios or transmission stages. The overall transmission ratios from the drive shaft of the electric motor to the wheel drive shafts via the transmission stages are low-speed transmission ratios.

[0016] The drive shaft is a drive shaft driven by an electric motor. The axle differential distributes the drive power to the wheels via the wheel drive shafts. The axle differential can be a lockable differential, preferably one with a differential lock. The drive shaft is connected to the first intermediate shaft via the first gear stage. The first drive shaft is permanently connected to the first intermediate shaft via the first gear stage, i.e., it cannot be shifted, so that this first gear stage, realized by the first gear stage, is always in the power flow. Furthermore, the first intermediate shaft is permanently connected to the hollow shaft via the second gear stage, or it can be shifted.

[0017] The axle drive includes an additional intermediate shaft arranged parallel to the wheel drive shafts, hereinafter referred to as the second intermediate shaft. The second intermediate shaft serves as a countershaft. The second intermediate shaft is arranged on an opposite side of the hollow shaft relative to the first intermediate shaft. In other words, the distances between the hollow shaft and the first intermediate shaft and the second intermediate shaft are smaller than the distance between the first intermediate shaft and the second intermediate shaft.

[0018] The second intermediate shaft is connected to the axle differential via a further gear ratio, preferably fixed, i.e., non-switchable. This gear ratio is referred to below as the fourth gear ratio.

[0019] Furthermore, a third gear ratio stage is provided, which is arranged to drive the hollow shaft to the second intermediate shaft.

[0020] According to a possible variant of the first embodiment, the axle transmission is designed as a 1-speed transmission, wherein the drive shaft is drivingly connected to the axle differential via the first intermediate shaft, the second intermediate shaft, the hollow shaft and the transmission stages.

[0021] Depending on the number of gears, it is possible to add gear ratios and switching units for switching the gear ratios.

[0022] According to a further variant of the first embodiment, the axle drive is designed as a multi-speed transmission, preferably an automated multi-speed transmission, for example, as a 2- or 3-speed transmission. The axle drive further comprises a shifting element, hereinafter referred to as the first shifting element, which is arranged for the selective, rotationally fixed connection of the hollow shaft to the axle differential, in particular to the axle differential housing. The axle drive further comprises a further shifting element, hereinafter referred to as the second shifting element, which is arranged for the selective, driving connection of the hollow shaft to the second intermediate shaft via the third gear ratio.

[0023] For example, the axle transmission can be designed as a 2-speed transmission, whereby in the lowest gear the hollow shaft is drivingly connected to the axle differential via the third and fourth gear ratios, the second shifting element and the second intermediate shaft, and in the highest gear the hollow shaft is non-rotatably connected to the axle differential directly via the first shifting element.

[0024] For example, the axle drive can also be designed as a 3-speed transmission, which also has an additional gear ratio, hereinafter referred to as the fifth gear ratio, which is arranged to drive the hollow shaft to the second intermediate shaft. Thus, instead of a 2-speed transmission, a 3-speed transmission can be easily implemented, in which the fifth gear ratio is additionally provided. The other shafts and gear ratios do not need to be changed. However, the ratios of the existing gear ratios can be adapted to the new application.

[0025] For the selective driving connection of the fifth gear ratio with that of the second intermediate shaft, either the second switching element can also be used, which in this case is designed both for the selective rotationally fixed connection of the hollow shaft with the second intermediate shaft via the third and also the fifth gear ratio, or alternatively a third switching element can be arranged which is only intended for the selective driving connection of the fifth gear ratio with the second intermediate shaft.

[0026] The 3-speed transmission based on the first embodiment can further be designed such that the hollow shaft is drivingly connected to the axle differential in the lowest two gears either via the fourth and third gear ratios or via the fourth and fifth gear ratios and the second intermediate shaft. In other words, the power transmission between the hollow shaft and the second intermediate shaft occurs either via the third or the fifth gear ratio, depending on whether first or second gear is engaged.

[0027] In top gear, the hollow shaft is connected to the axle differential directly via the first shift element, ensuring a fixed rotation. This is particularly advantageous because, in top gear, only two gear meshes under load to transfer power between the drive shaft and the axle differential. This means that the power flow from the drive shaft to the axle differential is realized only via the first and second gear ratios, but not via the third or, if present, the fifth gear ratio. This results in high drive efficiency.

[0028] According to a further aspect of the first embodiment, the first and second gear ratios can be arranged on the same side of the axle differential—viewed in the axial direction—as the third and / or fifth gear ratios. Furthermore, the input shaft can be arranged on the same side of the axle differential—viewed in the axial direction—as the hollow shaft. "Viewed in the axial direction" means in a direction parallel to the direction of the axle differential axis or the rotational axis of the hollow shaft or wheel drive shafts. These aspects enable a particularly compact design of the axle transmission and the closest possible arrangement of the electric motor to the wheel drive shafts or axle differential.

[0029] According to a further aspect of the first embodiment, the length of the first intermediate shaft may be shorter than the length of the hollow shaft and / or shorter than the length of the second intermediate shaft, if present.

[0030] According to a further aspect, the gear ratios can be designed as spur gear ratios. For example, the third gear ratio of the first embodiment can be designed as a spur gear ratio, wherein an idler gear of the third spur gear ratio can be connected in a rotationally fixed manner to the second intermediate shaft via the second shifting element. Alternatively, an idler gear of the third spur gear ratio can be connected in a rotationally fixed manner to the hollow shaft via the second shifting element.

[0031] Furthermore, the fifth gear ratio of the first embodiment can be designed as a spur gear stage. In this case, an idler gear of the fifth spur gear stage can be rotationally fixedly connected to the second intermediate shaft via the third shifting element. Alternatively, an idler gear of the fifth spur gear stage can be rotationally fixedly connected to the hollow shaft via the third shifting element.

[0032] According to a further aspect of the first embodiment, the first, second, and / or third shifting element can be designed as a positive-locking shifting element. It is particularly preferred if the positive-locking shifting element is designed as a dog clutch, so that more complex multi-plate clutches are not required. Furthermore, synchronization can be achieved via the electric motor control, thus eliminating the need for additional synchronizing units.

[0033] In an alternative embodiment according to the invention, the first gear ratio and the second gear ratio are arranged on different sides of the axle differential, viewed in the axial direction. This arrangement is particularly advantageous for implementing axle transmissions with up to five gears using a modular approach, as explained below.

[0034] A further intermediate shaft is provided, arranged parallel to the wheel drive shafts and serving as a countershaft. This further intermediate shaft of the second embodiment is referred to below as the second intermediate shaft. The second intermediate shaft is arranged on an opposite side of the hollow shaft with respect to the first intermediate shaft and is drivingly connected to the axle differential, preferably fixedly, i.e., non-switchably connected. The driving connection of the second intermediate shaft to the axle differential can be achieved via a further gear ratio, which is referred to below as the fourth gear ratio, to better distinguish it from the other gear ratios provided according to the inventive alternative.According to the alternative according to the invention, a further transmission stage is also provided, hereinafter referred to as the third transmission stage, which is arranged for drivingly connecting the hollow shaft to the second intermediate shaft and is preferably designed as a switchable spur gear stage.

[0035] According to a further aspect of the first variant of the second embodiment, the axle transmission can further comprise a shifting element arranged for the selective, rotationally fixed connection of the hollow shaft to the axle differential, in particular to the axle differential housing. This shifting element is referred to below as the first shifting element. This is particularly advantageous for the implementation of multi-speed transmissions based on the second embodiment, in order to transfer the drive power to the axle differential in the highest gear with as little gear meshing as possible, in which the hollow shaft is directly connected to the axle differential in a rotationally fixed manner by means of the first shifting element.

[0036] Accordingly, it is possible to design the axle transmission according to this aspect as a multi-speed transmission, wherein, in order to realize the highest gear, the hollow shaft is connected in a rotationally fixed manner to the axle differential, in particular to the axle differential housing, via the first switching element and the second intermediate shaft is not drivingly connected to the hollow shaft.

[0037] The gear ratios according to the first variant of the second embodiment can be designed as spur gear stages.

[0038] According to an advantageous second variant of this second embodiment, the axle transmission further comprises a transmission stage arranged for drivingly connecting the hollow shaft to the axle differential, wherein the transmission stage is realized via a planetary gear whose sun shaft corresponds to the hollow shaft and a planet carrier of the planetary gear is part of a housing of the axle differential or is fixedly connected to the housing of the axle differential.

[0039] This gear ratio will be referred to below as the third gear ratio to better distinguish the further differentiation levels that are provided according to the second variant of the second embodiment or that can be optionally used. It is therefore emphasized again that the third gear ratio of the second variant of the second embodiment is to be distinguished from the third gear ratio of the first variant of the second embodiment or from the optional third gear ratio of the variants of the first embodiment, as described above.

[0040] This second variant of the second embodiment enables a particularly compact design of the axle drive in a direction perpendicular to the axle axial direction due to the planetary gear, since a second intermediate shaft can be dispensed with to realize a fourth or fifth gear.

[0041] According to a further aspect of the second variant of the second embodiment, the axle drive can be designed as a multi-speed transmission, with the planetary gear being connected in a block circuit to realize the highest gear. This, in turn, enables high drive efficiency, since the power flow from the drive shaft to the axle differential is realized only via the first and second gear ratios, but not via a further gear ratio through the planetary gear or, if present, a further gear ratio. In low gears, where high gear ratios are required, the planetary gear converts the power with a gear ratio other than 1.

[0042] According to a further aspect of the second variant of the second embodiment, the axle transmission can further comprise a further gear ratio, hereinafter referred to as the fourth gear ratio, which is arranged for the driving connection of the first intermediate shaft and the axle differential and is preferably designed as a switchable spur gear stage.

[0043] According to a further aspect of the second variant of the second embodiment, the axle transmission can further comprise a further gear ratio, hereinafter referred to as the fifth gear ratio, which is arranged for drivingly connecting the first intermediate shaft and the hollow shaft and is preferably designed as a switchable spur gear stage.

[0044] The gear ratios according to the second variant of the second embodiment can be designed as spur gear ratios - except for the third gear ratio, which is realized via the planetary gear.

[0045] With such fourth and fifth gear ratios, additional gear stages or gears can be realized optionally and in a modular manner.

[0046] In variants of the second embodiment, the first gear ratio can be arranged—as viewed in the axial direction—on a different side of the axle differential than the third gear ratio according to the first or second variant, or like the fifth gear ratio, if present. Accordingly, in the second embodiment, the first intermediate shaft can extend axially from one side of the axle differential to the opposite side of the axle differential.

[0047] The axle drive of the second embodiment can be designed as a multi-speed transmission, preferably as an automated multi-speed transmission. The number of gears can be varied by the number of optional third to fifth gear ratios. The ratios of the gear ratios can be adapted to the new application. Corresponding shifting elements are provided for shifting the individual gear ratios, preferably each designed as a positive-locking shifting element. A design of the shifting elements as a claw clutch is particularly preferred.

[0048] For example, a shifting element may be provided that is arranged for the selective driving connection of the first intermediate shaft and the hollow shaft via the second gear ratio. For example, in an axle drive according to the first variant of the second embodiment, a shifting element may be provided that is arranged for the selective driving connection of the hollow shaft and the second intermediate shaft via the third gear ratio. For example, in an axle drive according to the second variant of the second embodiment, a shifting element may be provided that is arranged for the selective driving connection of the first intermediate shaft and the axle differential via the fourth gear ratio.For example, in an axle transmission according to the second variant of the second embodiment, a switching element can be provided which is arranged for the selective driving connection of the hollow shaft with the ring gear of the planetary gear or the planet carrier of the planetary gear and / or which is arranged for the selective driving connection of the ring gear with the transmission housing, the planet carrier or the hollow shaft (sun).

[0049] The invention further relates to an axle drive device for an electrically driven axle of a commercial vehicle, comprising an axle transmission as described in this document and further comprising an electric machine having the drive shaft arranged parallel to the wheel drive shafts.

[0050] The axle drive device can comprise a rigid axle body of a rigid axle of a commercial vehicle, into which the axle drive and the electric motor are integrated or at least partially integrated. A housing of the axle body thus encloses the axle drive and preferably also the electric motor.

[0051] In one embodiment of the axle drive device in which the axle transmission is designed as a multi-speed transmission, the drive device can be configured to synchronize the control of shifting elements for switching the gear ratios depending on the control of the electric motor, thereby advantageously eliminating the need for additional synchronizer units. For example, it is conceivable for the shifting elements, in particular a shifting element of the switchable planetary gear, to be designed as a dog clutch with synchronizers. This is particularly advantageous since, when shifting planetary gears, it may be possible for rotational speeds to not be detected or adjusted.

[0052] The invention further relates to a motor vehicle having an axle transmission or axle drive device as described in this document. By way of example only, the vehicle may be a commercial vehicle, i.e., a vehicle whose design and equipment are designed to transport people, goods, or trailers. Thus, the vehicle may be, for example, a truck, a semitrailer truck, and / or a bus.

[0053] According to a second general aspect, the present disclosure relates to a modular transmission system for a motor vehicle, preferably a commercial vehicle. The modular transmission system comprises a plurality of different axle drives, each axle drive having at least the basic module as described above. The plurality of axle drives can each differ in their number of gears.

[0054] The modular transmission system can reduce manufacturing costs through economies of scale by reusing the basic module. Depending on the required performance of the axle drive, the basic module can be optionally expanded with additional gear ratios and the corresponding shifting elements. In this way, different axle drives can be derived from the same basic module. This allows drivetrains with different power outputs to be constructed, allowing a wide range of different motor vehicles to use the modular transmission system (e.g., light, medium, and heavy trucks). For example, an entire fleet portfolio for electric commercial vehicles can be covered in this way.

[0055] The proposed axle drive kit can be used, for example, by manufacturers of axle drives or motor vehicles. These manufacturers typically offer axle drives or motor vehicles of different series or variants for different applications. The design of the axle drive usually depends on the application and can often be assigned to specific performance classes. Typically, a higher number of gears is provided for axle drives for applications in which the axle drive must transmit higher torques or speeds than for applications with lower torque or speed ranges. The vehicle fleets of motor vehicle manufacturers or the portfolio of transmission manufacturers are therefore usually composed of several independent variants of axle drives with different numbers of gears, gear ratio spreads, etc.

[0056] According to a preferred embodiment, a modular transmission system is provided that exclusively comprises axle transmissions constructed either according to the first embodiment and its variants, as described above, or according to the second embodiment and its variants, as described above. This allows manufacturing costs and economies of scale to be further improved.

[0057] In an advantageous variant of this embodiment of the modular transmission system, the basic module is of identical design for all axle drives and / or is made of identical parts.

[0058] In a further advantageous variant of this embodiment, the modular transmission kit is designed such that in all axle drives of the modular transmission kit, the center distance between the drive shaft and the first intermediate shaft is the same. This can apply to all variants described here. In a further advantageous variant of this embodiment, the modular transmission kit is designed such that in all axle drives of the modular transmission kit, the center distance between the hollow shaft and the first intermediate shaft is the same, and / or the center distance between the hollow shaft and the second intermediate shaft, if present, is the same; and / or the bearing points are the same; and / or the positioning and gear ratio of the axle differential and / or the housing parts of the axle differential are the same.

[0059] This will enable manufacturing costs, economies of scale and the number of common parts to be further improved when producing axle drives with different power levels and gears.

[0060] The invention further relates to a modular axle drive system for a motor vehicle, preferably a commercial vehicle, comprising a plurality of different axle drive systems, each of which has an axle transmission derived from the modular transmission system. The modular axle drive system can comprise axle drive systems in which the axle body is identical.

[0061] Further details and advantages of the invention are described below with reference to the accompanying drawings. They show: Fig. 1 is a schematic view of an axle drive according to a first embodiment of the invention; Fig. 2 a schematic view of the embodiment of Fig. 1 and power flow with first gear engaged; Fig. 3 a schematic view of the embodiment of Fig. 1 and power flow with second gear engaged; Fig. 4 a schematic sectional view of the embodiment of Fig. 1 and power flow with third gear engaged; Fig. 5 Tabular overview of the switching states of the switching elements designed as clutches of the embodiment from Fig. 1 in first to third gear; Fig. 6 is a schematic view of an axle drive according to a first variant of a second embodiment of the invention; Fig. 7 a schematic view of the embodiment of Fig. 6 and power flow with first gear engaged; Fig. 8 is a schematic view of the embodiment of Fig. 6 and power flow with second gear engaged; Fig. 9 is a schematic view of the embodiment of Fig. 6 and power flow with third gear engaged; Fig. 10 is a schematic view of the embodiment of Fig. 6 and power flow with fourth gear engaged; Fig. 11 Tabular overview of the switching states of the switching elements designed as clutches of the embodiment from Fig. 6 in first to fourth gear; Fig. 12 Tabular overview of the switching states of the switching elements designed as clutches of the embodiment from Fig. 13 in first to fifth gear according to a second variant of the second embodiment of the invention; Fig. 13 is a schematic view of an axle drive according to a second variant of the second embodiment of the invention; Fig. 14 is a schematic view of the embodiment of Fig. 13 and power flow with first gear engaged; Fig. 15 is a schematic view of the embodiment of Fig. 13 and power flow with second gear engaged; Fig. 16 is a schematic view of the embodiment of Fig. 13 and power flow with third gear engaged; Fig. 17 is a schematic view of the embodiment of Fig. 13 and power flow with fourth gear engaged; Fig. 18 is a schematic view of the embodiment of Fig. 13 and power flow with fifth gear engaged; Fig. 19 is an isometric view of the embodiment of Fig. 1, and Fig. 20 a schematic representation of an exemplary modular system.

[0062] Identical or functionally equivalent elements are designated by the same reference numerals in all figures and are not described separately in some cases. For example, reference numeral 1 designates the axle differential in all embodiments, with the axle differential housing being designed differently depending on the embodiment and variant.

[0063] The representation of reference symbols has been taken into account, particularly in the Fig. 2 to 4, 7 to 10, and 14 to 18, have largely been omitted for the sake of clarity. Instead, the figures cited only indicate the reference numerals of those clutch points of the shift elements that are engaged in the respective gear (see the information in the figure title).

[0064] The three design variants of the axle drive 100, 200, and 300 described below are based on the idea of ​​providing a modular system for implementing different variants of an axle drive 100, 200, and 300 for an electrically driven axle of a motor vehicle using identical parts. The three embodiments described below are each based on a basic module, which can optionally be supplemented with additional assemblies and components. These modular assemblies are indicated in the figures by dotted-line frames.

[0065] The Fig. 1, Fig. 6 and Fig. The three design variants of the proposed axle drive 100, 200, 300 shown in Figure 12 serve to transmit and transform drive power 4 from an electric motor into wheel drive power 5 and deliver it to (not shown) motor vehicle wheels to drive the motor vehicle. The power flow can also be in the opposite direction in a manner known per se, i.e., traction energy can be transmitted from the motor vehicle wheels via the axle drive 100, 200, 300 to the electric motor, i.e., from the hollow shaft via the intermediate shaft and drive shaft with the first two gear ratios to the electric motor. In the following, it is assumed that the power flow leads from the electric motor to the wheel drive shafts.

[0066] Fig. Figure 1 shows a purely schematic view of an axle drive 100 according to a first embodiment of the invention. The motor vehicle can expediently be designed as a commercial vehicle, in particular as a truck.

[0067] The axle drive 100 has a base module 100a, which has an axle differential 1 lockable by a differential lock 109, and two wheel drive shafts 3a, 3b driven by the axle differential 1. Furthermore, the base module 100a has a drive shaft (input shaft) 2 driven by an electric machine 6 (electric motor). It has already been stated above that the axle drive is not limited to electric axles, but could also be connected to other mechanical power sources. However, the highlighted embodiment of an electric axle is described here. The drive shaft 2 is designed to receive and transmit drive power 4 from the electric motor or to deliver drive power 4 to the electric motor. The electric motor is preferably an electric motor arranged transversely to the motor vehicle axle, i.e., parallel to the wheel drive shafts 3a, 3b. Fig. The electric motor 6 indicated in Figure 1 is arranged coaxially to the drive shaft 4. The basic module 100a further comprises a first intermediate shaft 101. The drive shaft 2 and the first intermediate shaft 101 are also arranged parallel to the wheel drive shafts 3a, 3b and are drivingly connected to one another via a first transmission stage 110. The basic module 100a further has a hollow shaft 102, which is arranged coaxially to the wheel drive shafts 3a, 3b and encloses one of the wheel drive shafts 3a or 3b. One of the wheel drive shafts 3a, 3b runs at least partially radially inside the hollow shaft 102. The first intermediate shaft 101 and the hollow shaft 102 are drivingly connected via a second transmission stage 120. A basic module with the aforementioned components is also correspondingly available in the embodiments 200 (cf. Fig. 6) and 300 (cf. Fig. 13). Reference numeral 400 denotes an axle drive device comprising the axle transmission 100 and the electric machine 6.

[0068] At the Fig. 1, a special feature is that the second gear stage 120 - viewed in the axial direction D - is arranged on the side of the axle differential 1 on which the first gear stage 110 is also located.

[0069] The first gear stage 110 is preferably designed as a spur gear stage, with the drive gear or driving pinion 111 (assuming traction operation) arranged on the drive shaft 2 and connected thereto as a fixed gear for rotation therewith (traction operation). The driven gear 112 is arranged on the first intermediate shaft 101 and also connected thereto as a fixed gear for rotation therewith. It should be noted again that the gear stage 110, as well as all gear stages described below, are designed in a conventional manner for an opposite power flow in overrun mode, i.e., a driving gear 112 and a driven pinion 111.

[0070] The second gear stage 120 is preferably designed as a spur gear stage, with the drive gear or driving pinion 121 arranged on the first intermediate shaft 101 and connected thereto as a fixed gear in a rotationally fixed manner. The driven gear 122 is arranged on the hollow shaft 102 and connected thereto as a fixed gear in a rotationally fixed manner.

[0071] The axle drive 100 further includes a second intermediate shaft 103 arranged parallel to the wheel drive shafts 3a, 3b, designed as a countershaft, which is arranged on an opposite side of the hollow shaft 102 with respect to the first intermediate shaft 101. The shafts 2, 101, 102, 103 and 3a, 3b are thus parallel to one another.

[0072] The second intermediate shaft 103 and the hollow shaft 102 are connected via at least one gear ratio. Fig. In the first embodiment shown in Figure 1, this drive connection can be established, for example, via the third gear ratio 130. The second intermediate shaft 103 and the axle differential 1 are also drive-connected via the fourth gear ratio 140, the so-called "final drive." The fourth gear ratio 140 is preferably designed as a spur gear stage, with the drive gear or driving pinion 141 being arranged on the second intermediate shaft 103 and being connected thereto in a rotationally fixed manner as a fixed gear. The driven gear 142 is arranged on the differential housing and is connected thereto in a rotationally fixed manner. The axle differential 1, in turn, is drive-connected to the wheel drive shafts 3a, 3b in a manner known per se.

[0073] At least with regard to the first embodiment of the axle drive 100, the aforementioned components, including the second intermediate shaft 103 and the third gear ratio, can also be considered part of the basic module 100a. Based on these components, different axle drives can now be realized, in particular axle drives designed as 1-speed, 2-speed, or 3-speed transmissions, with additional assemblies being added depending on the implemented design variant.

[0074] In Fig. 1 shows a realization as a 3-speed variant of the axle drive 100.

[0075] In the 3-speed variant of the axle drive 100, in addition to the third gear ratio, a further gear ratio 150 is arranged for the driving connection of the hollow shaft 102 with the second intermediate shaft 103, which is referred to here as the fifth gear ratio 150. Both gear ratios 130, 150 are designed as switchable gear ratios.

[0076] The third gear stage 130 and the fifth gear stage 150 can drive the hollow shaft 102 to the second intermediate shaft 103. The gear stages 130 and 150 each have a driving pinion 131, 151, exemplified as a fixed gear, and a driven gear 132, 152, exemplified as an idler gear. The pinion 131 or 151 meshes with the gear 132 or 152. The pinions 131, 151, exemplified as fixed gears, are arranged side by side on the hollow shaft 102 in a rotationally fixed manner. The gears 132, 152 are arranged side by side on the second intermediate shaft 103. The gears 132, 152, exemplified as idler gears, are rotatably mounted on the second intermediate shaft 103. The gear ratios 130 and 150 are preferably designed as spur gear stages with two spur gears each.

[0077] The shifting element 105 can connect the wheels 132, 152 in a rotationally fixed manner and thus drivingly to the second intermediate shaft 103. In a first shift position (first gear), the shifting element 105 drives the wheel 132 to the second intermediate shaft 103. Only the clutch point 105b is closed. In a second shift position (second gear), the shifting element 105 drives the wheel 152 to the second intermediate shaft 103. Only the clutch point 105a is closed. In a third shift position (neutral position), the shifting element 105 does not drive any of the wheels 132, 152 to the second intermediate shaft 103. The clutch points 105a, 105b are both open. The shifting element 105 can preferably be designed as a positive-locking shifting element, in particular as a pure claw clutch. However, it is also possible that the switching element 105 is designed, for example, as a frictional switching element.Actuation of the switching element 105 can be controlled by a control unit (not shown), which is embodied in particular as a transmission control unit. For this purpose, the control unit can correspondingly control an actuator (not shown) designed to move the switching element 105. The actuator can be embodied, for example, as a pneumatic actuator or an electromechanical actuator. The control unit can also, for example, control the operation of the electric machine 6. Furthermore, the control of the switching element 105 can be synchronized via the electric machine control, thereby eliminating the need for synchronization units.

[0078] In the 3-speed variant of the axle transmission 100, the assembly 107a is also provided. The assembly 107a comprises a first shifting element 104, which is arranged for the selective, rotationally fixed connection of the hollow shaft 102 to the axle differential 1 and can be moved into a closed position and an open position. The shifting element 104 is preferably designed as a switchable claw clutch 104, which, in a closed position, can establish a positive connection between the hollow shaft 102 and the axle differential 1, in particular the axle differential housing, via the clutch point 104a.

[0079] In the closed position, the clutch point 104a is closed, so that the hollow shaft 102 is connected to the axle differential 1 in a rotationally fixed manner. In the open position, the clutch point 104a is open, so that the hollow shaft 102 is not connected to the axle differential 1 in a rotationally fixed manner. The switching element 104 is controlled analogously to the switching element 105 via the control unit and an actuator assigned to the switching element 104. In 3rd gear, the clutch point 104a is closed, but in 1st and 2nd gear it is open. In 3rd gear, the switching element 105 is in the neutral position, so that the clutch points 105a and 105b are open.

[0080] The switching positions of the switching elements 105 and 106 in the first, second and third gear are in Fig. 5 shown in tabular form.

[0081] The Fig. Figures 2 to 4 illustrate the power flows in first to third gear, each represented by the thick dotted line. The power flow of the engaged first gear of this 3-speed variant of the first embodiment is shown in Fig. 2. In a first shift position (first gear), the shift element 105 drivingly connects the wheel 132 to the second intermediate shaft 103. Only the clutch point 105b is closed. The drive power 4 is transmitted via the drive shaft 2 via the first gear stage 110 to the first intermediate shaft 101, via the second gear stage 120 to the hollow shaft 102, via the third gear stage 130 to the second intermediate shaft 103, and via the fourth gear stage 140 to the axle differential 1, and then in a conventional manner to the wheel drive shafts 3a, 3b.

[0082] The power flow of the second gear of this 3-speed variant of the first embodiment is in Fig. 3. In the second shift position (second gear), the shift element 105 connects the wheel 152 to the second intermediate shaft 103. Only the clutch point 105a is closed. The power flow is therefore different from that in Fig. 2 in that the torque of the hollow shaft 102 is transmitted via the transmission stage 150 instead of via the transmission stage 130.

[0083] The power flow of the engaged third gear is in Fig. 4. The shift element 105 is in the neutral position, and the shift element 104 is in the closed position. The drive power 4 is transmitted via the drive shaft 2 through the first gear stage 110 to the first intermediate shaft 101, via the second gear stage 120 to the hollow shaft 102, and from the hollow shaft 102 directly to the axle differential 1 and then, in a conventional manner, to the wheel drive shafts 3a, 3b.

[0084] To realize a 1-speed variant of the axle drive, the assembly 107a, which includes the switching element 104 for connecting the hollow shaft 102 to the axle differential housing in a rotationally fixed manner, is omitted. Furthermore, in the 1-speed variant, only one gear ratio is provided for the driving connection of the hollow shaft 102 to the second intermediate shaft 103, i.e., either the gear ratio 130 or 150, which then - in contrast to the illustration in Fig. 1 - is not switchable, so that this transmission stage connects the hollow shaft 102 firmly to the second intermediate shaft 103.

[0085] To implement a 2-speed variant, there are two alternative possibilities in the first embodiment of the axle drive 100, starting from the Fig. 1 shown 3-speed variant: 1. Omitting the assembly 107a or the switching element 104, or alternatively 2. Omission of one of the two assemblies 107b or 107c, i.e. omission of one of the two switchable gear ratios 130 or 150.

[0086] Accordingly, only two of the Fig. 5 shown gear stages can be realized or only two of the gear stages shown in the Fig. 2 to 4 - depending on which assembly 107a, 107b or 107c is omitted.

[0087] It is evident that, starting from the basic module 100a, different axle transmission variants can be produced by different combinations of the assemblies 107a, 107b and 107c, which can be provided as part of a transmission kit 600. This is shown only schematically in Fig. 20 illustrated.

[0088] The Fig. Figure 20 shows purely by way of example how the described modular transmission system 600 can be used to create a broad axle drive portfolio for different applications in the commercial vehicle sector.

[0089] The modular axle drive system can comprise several axle transmissions, all of which have the same basic module 100a and are differentiated by the optional assemblies 107a, 107b, and 107c, as outlined above for the 1- to 3-speed variants.

[0090] Here, the modular transmission system can only include axle drives where a1) the center distance between the drive shaft 2 and the first intermediate shaft is the same, and / or a2) the center distance between the hollow shaft 102 and the first intermediate shaft is the same, and / or a3) the center distance between the hollow shaft 102 and the second intermediate shaft, if present, is the same; and / or b) the bearing points are the same; and / or c) the positioning and ratio of the axle differential and / or the housing parts of the axle differential are the same. This results in packaging advantages, as the installation space required for the axle drive is the same in all variants. Furthermore, all axle drive variants can be accommodated in the same axle bridge (axle housing of the rigid axle).

[0091] Trucks up to, for example, 12 t can use a single-speed transmission. Trucks between, for example, 12 t and 28 t can use a two- or three-speed transmission. Trucks between, for example, 28 t and 44 t can use a more powerful two- or three-speed transmission. Trucks over, for example, 44 t can use a two- or three-speed transmission on two driven axles (tandem). It is emphasized again that this classification is only an example.

[0092] The above-described gear ratios 110, 120, 130, 140 and 150 as well as the further gear ratios 210, 310, 220, 320, 130, 230, 330, 240, 340, 250, 350 of the further embodiments to be described below are designed to convert or transform the speed and / or torque of the driving shaft according to their gear ratio. The gear ratio of these gear stages results in the embodiments shown from the diameter or tooth number ratio of a drive wheel or driving pinion 111, 121, 131, 141, 151 and a driven wheel 112, 132, 142, 152 meshing with the pinion 111, 121, 131, 141, 151. In other words, the gear stages 110, 210, 310, 120, 220, 320, 130, 230, 330, 140, 240, 340, 150, 250, 350 in the embodiments shown are designed as gear stages, in particular spur gear stages.However, in further embodiments not shown, other components designed to transform speed and / or torque, for example toothed belt transmission stages, chain transmission stages, hydraulic transmission stages or electric transmission stages, etc., are also conceivable.

[0093] Below, a further embodiment is described in a first variant ( Fig. 6 to 12) and a second variant ( Fig. 14 to 19).

[0094] Fig. 6 shows the axle drive 200 in a first variant of a second embodiment.

[0095] The basic module 200a of the first variant of the second embodiment of the axle drive 200 also has the previously described axle differential 1, the drive shaft (input shaft) 2, and the wheel drive shafts 3a, 3b. Analogous to the first embodiment, the drive shaft (input shaft) 2 is also in a driving connection with the first intermediate shaft 201 via the first gear ratio 210.

[0096] The basic module 200a further comprises a hollow shaft 202, which is drivingly connected to the first intermediate shaft 201 via a second transmission stage 220.

[0097] In contrast to the base module 100a of the first embodiment of the axle drive 100, the first gear stage 210 and the second gear stage 220—viewed in the axial direction—in the base module 200a are preferably arranged on different sides of the axle differential 1. The first intermediate shaft 201 is designed to be correspondingly longer. Such an arrangement is not necessary for pure functionality, but is particularly advantageous for optimal use of installation space or package utilization.

[0098] The hollow shaft 202 is drivingly connected to a second intermediate shaft 203 via the third gear stage 230. The second intermediate shaft 203 is drivingly connected to the axle differential 1 via a fourth gear stage 240, the so-called "final drive." The axle differential 1, in turn, is connected to the wheel drive shafts 3a, 3b in a manner known per se. With these components, a 1-speed variant of the axle transmission can be implemented, analogous to the 1-speed variant of the Fig. 1.

[0099] This 1-speed variant can be modularly expanded to include individual gears in analogy to what has already been described by adding additional assemblies 207a, 207b, 207c to the basic module 200a.

[0100] For the sake of clarity, only the configuration with the highest achievable number of gears, namely the 4-speed variant, is described below. However, it should be noted that a 2-speed or 3-speed version of the 200 axle drive can also be implemented by omitting individual components.

[0101] To implement a 4-speed variant, the axle transmission 200 in the second embodiment has all Fig. 6 shown components, in particular all assemblies 207a, 207b and 207c.

[0102] A shifting element 205 is arranged on the first intermediate shaft 201, which can connect the drive wheels 251, 221 in a rotationally fixed and thus driving manner to the first intermediate shaft 201. Analogous to the shifting element 205, the shifting element can be designed as a clutch actuated by an actuator, wherein a rotationally fixed, positive connection can be established between the first intermediate shaft 201 and the fifth gear stage 250 via the clutch point 205a of the shifting element 205. Via the second clutch point 205b, the clutch 205 can establish a positive connection between the first intermediate shaft 201 and the second gear stage 220.

[0103] The second gear stage 220 and the fifth gear stage 250 can be designed as switchable spur gear stages. For example, the clutch 205 can be designed as a claw clutch that engages a gear ring arranged on the pinions 221 or 251. If the clutch point 205a is closed, the pinion 221 is a loose gear through which no power can be transmitted. If the clutch point 205b is closed, the pinion 251 is a loose gear through which no power can be transmitted.

[0104] The gear 222 of the second gear stage 220, the gear 252 of the fifth gear stage 250, and the pinion 231 of the third gear stage 230 are connected in a rotationally fixed manner to the hollow shaft 202. It is also possible to implement the pinion 231 in the gear stage 230 as a loose gear and to connect the gear 232 in a rotationally fixed manner to the second intermediate shaft 203. In this case, the clutch 206 would be omitted. In this case, it is conceivable to design the clutch 204, here again a claw clutch, with two clutch points, 204a and 204b, plus a neutral position. For efficiency reasons (smaller needle bearings), the gear 232 of the gear stage 230 was designed here as a loose gear.

[0105] Via the clutch 204, a positive connection between the hollow shaft 202 and the axle differential 1 can be established in the clutch point 204a (closed position).

[0106] In the 4-speed variant of the second embodiment of the axle drive 200, the third gear stage 230 is designed as a switchable spur gear stage. For this purpose, a switching element 206, preferably a switchable claw clutch, is arranged in a rotationally fixed manner on the second intermediate shaft 203, with which a positive connection can be established between the gear 232 and the second intermediate shaft 203 by closing the coupling point 206a.

[0107] The first, second, third and fourth gears are realized solely by selective, coordinated switching of the switching elements 204, 205 and 206. The switching points of the switching elements 205, 205, 206 in the first, second, third and fourth gears are in Fig. 11 are shown in tabular form. The switching elements are also referred to as clutches below and can, for example, be designed as claw clutches.

[0108] The power flow of the first gear of this 4-speed variant of the second embodiment is in Fig. 7. Clutch point 205b is closed. Clutch point 206a is closed. The drive power 4 is transmitted via the drive shaft 2, via the first gear stage 210 to the first intermediate shaft 201, via the second gear stage 220 to the hollow shaft 202, via the third gear stage 230 to the second intermediate shaft 203, via the fourth gear stage 240 to the axle differential 1, and then, in a conventional manner, to the wheel drive shafts 3a, 3b. By closing clutch point 205b, pinion 251 becomes a loose gear through which no power is transmitted.

[0109] The power flow of the second gear of this 4-speed variant of the second embodiment is in Fig. 8. Clutch point 205a is closed. Clutch point 206a is closed. The drive power 4 is transmitted via the drive shaft 2 via the first gear stage 210 to the first intermediate shaft 201, via the fifth gear stage 250 to the hollow shaft 202, via the third gear stage 230 to the second intermediate shaft 203, via the fourth gear stage 240 to the axle differential 1, and then in a conventional manner to the wheel drive shafts 3a, 3b. By closing clutch point 205a, the pinion 221 becomes a loose wheel through which no power is transmitted. Clutch point 204a of clutch 204 is not closed, so that no power is transmitted between the hollow shaft 202 and the axle differential 1.

[0110] The power flow of the third gear of this 4-speed variant of the second embodiment is in Fig. 9. Clutch point 205b is closed. Clutch point 204a of clutch 204 is closed. The drive power 4 is transmitted via the drive shaft 2, via the first gear stage 210 to the first intermediate shaft 201, via the second gear stage 220 to the hollow shaft 202, via the clutch 204 to the axle differential 1, and then, in a conventional manner, to the wheel drive shafts 3a, 3b. By closing clutch point 205b, the pinion 251 becomes a loose gear through which no power is transmitted. Clutch point 206a of clutch 206 is not closed, so no power is transmitted between the hollow shaft 202 and the second intermediate shaft 203.

[0111] The power flow of the fourth gear of this 4-speed variant of the second embodiment is in Fig. 10. Coupling point 205a of clutch 205 is closed. Clutch point 204a of clutch 204 is closed. The drive power 4 is transmitted via the drive shaft 2, via the first gear stage 210 to the first intermediate shaft 201, via the fifth gear stage 250 to the hollow shaft 202, via the clutch 204 to the axle differential 1, and then, in a conventional manner, to the wheel drive shafts 3a, 3b. By closing clutch point 205a of clutch 205, the pinion 221 becomes a loose gear through which no power is transmitted. Clutch point 206a of clutch 206 is not closed, so no power is transmitted between the hollow shaft 202 and the second intermediate shaft 203.

[0112] Fig. Figure 13 shows the axle drive 300 in a second variant of the second embodiment, in which no second intermediate shaft is used, but a planetary gear is used. The basic module 300a of the third embodiment of the axle drive 300 also has the previously described axle differential 1, the input shaft 2, and the wheel drive shafts 3a, 3b.

[0113] Furthermore, a first intermediate shaft 301 arranged parallel to the wheel drive shafts 3a, 3b, a hollow shaft 302 arranged coaxially to the wheel drive shafts 3a, 3b and at least one first gear stage 310 and one second gear stage 320 are provided, which are arranged for the driving connection of the drive shaft 2 to the axle differential 1 via the first intermediate shaft 301 and the hollow shaft 302.

[0114] Analogous to the basic module 200a of the axle drive 200 (cf. Fig. 6) the first translation stage 310 and the second translation stage 320 in the basic module 300a are in Fig. 13 - seen in axial direction - arranged on different sides of the axle differential 1.

[0115] In the embodiment of the Fig. Figure 13 shows a realization as a 4-speed axle drive, with additional components being provided which can be partially omitted to realize 1- to 3-speed axle drives according to the modular approach.

[0116] The additional assemblies include: 1. Assembly 307c, comprising a third gear stage 330 designed as a planetary stage; 2. Assembly 307a, comprising a fifth gear ratio stage 350; 3. Assembly 307d, comprising a fourth gear ratio 340.

[0117] The second gear ratio 320 and the fifth gear ratio 350 are also designed analogously to the embodiment variant 200 as spur gear ratios that can be switched via the switching element 305.

[0118] The fourth gear ratio 340 is also designed as a shiftable spur gear stage. For this purpose, a shifting element 306 in the form of a clutch 306 is arranged on the first intermediate shaft 301. By closing the clutch point 306a, a positive connection can be established between the first intermediate shaft 301 and the pinion 341.

[0119] The wheel 342 of the fourth gear stage 340 is connected in a rotationally fixed manner to the housing of the axle differential 336.

[0120] The third gear stage 330, designed as a planetary stage, comprises a sun pinion 331 connected to the hollow shaft 302 for rotation therewith, a plurality of planet gears 332 distributed around the circumference, and an internally toothed ring gear 333, which mesh with one another. A positive connection can be established between the ring gear 333 and the hollow shaft 302, or in another embodiment, between the ring gear 333 and the planet carrier 334, via the coupling point 304a of the coupling 304. By closing the coupling point 304a, the planetary stage rotates as a block. Furthermore, by closing the coupling point 304b of the coupling 304, a positive connection can be established between the ring gear and the transmission housing. By closing the coupling point 304b, the planet gears 332 rotate around the sun pinion 331. The planet gears 332 are arranged on the planet carrier 334. The planet carrier 334 is connected in a rotationally fixed manner to the housing of the axle differential 336 via the web 335.One revolution of the planet carrier 334 thus causes one revolution of the axle differential 1. By closing the clutch point 304a of the clutch 304 (block revolution), the third gear stage 330, designed as a planetary stage, has the gear ratio 1. By closing the clutch point 304b of the clutch 304 (block revolution), the third gear stage 330, designed as a planetary stage, has a gear ratio other than 1.

[0121] For the sake of clarity, only the configuration with the highest achievable number of gears, namely the 5-speed variant, is described below. However, it should be noted that by omitting individual components, a 1-speed, 2-speed, 3-speed, or 4-speed version of the 300 axle drive can also be implemented.

[0122] The first, second, third, fourth and fifth gears are realized solely by selective, coordinated switching of the switching elements 304, 305 and 306. The switching positions of the switching elements 304, 305, 306 in the first, second, third, fourth and fifth gears are in Fig. 12 are shown in tabular form. The switching elements are also referred to as clutches below and can, for example, be designed as claw clutches.

[0123] The power flow of the first gear of this 5-speed variant of the 300 version is in Fig. 14. Clutch point 305b of clutch 305 is closed. Clutch point 304b of clutch 304 is closed. The drive power 4 is transmitted via the drive shaft 2 via the first gear stage 310 to the first intermediate shaft 301, via the second gear stage 320 to the hollow shaft 302, via the third gear stage 330, designed as a planetary stage, to the axle differential 1, and then in a conventional manner to the wheel drive shafts 3a, 3b. By closing clutch point 305b of clutch 305, gear 351 is a loose gear through which no power is transmitted. By closing clutch point 304b of clutch 304, the ring gear 333 is fixed to the housing of the axle transmission 300, and the gear ratio of the third gear stage 330, designed as a planetary stage, is not equal to 1.

[0124] The power flow of the second gear of this 5-speed variant is in Fig. 15. Clutch point 305a of clutch 305 is closed. Clutch point 304b of clutch 304 is closed. The drive power 4 is transmitted via the drive shaft 2, via the first gear stage 310 to the first intermediate shaft 301, via the fifth gear stage 350 to the hollow shaft 302, via the third gear stage 330, designed as a planetary stage, to the axle differential 1, and then in a conventional manner to the wheel drive shafts 3a, 3b. By closing clutch point 305a of clutch 305, gear 321 is a loose gear through which no power is transmitted. By closing clutch point 304b of clutch 304, the ring gear 333 is fixed to the housing of the axle transmission 300, and the gear ratio of the third gear stage 330, designed as a planetary stage, is not equal to 1.

[0125] The power flow of the third gear of this 5-speed variant is in Fig. 16. Clutch point 305b of clutch 305 is closed. Clutch point 304a of clutch 304 is closed. The drive power 4 is transmitted via the drive shaft 2 via the first gear stage 310 to the first intermediate shaft 301, via the second gear stage 320 to the hollow shaft 302, via the third gear stage 330 designed as a planetary stage to the axle differential 1 and then in a manner known per se to the wheel drive shafts 3a, 3b. By closing clutch point 305b of clutch 305, the gear 351 is an idler gear via which no power is transmitted. By closing clutch point 304a of clutch 304, the planetary stage rotates the third gear stage 330 designed as a planetary stage in block form and has a gear ratio = 1.

[0126] The power flow of the fourth gear of this 5-speed variant is in Fig. 17. Clutch point 306a of clutch 306 is closed. The drive power 4 is transmitted via the input shaft 2 via the first gear stage 310 to the first intermediate shaft 301, via the fourth gear stage 340 to the axle differential 1, and then in a conventional manner to the wheel drive shafts 3a, 3b. Neither clutch point 305a nor 305b of clutch 305 are closed (neutral position). Consequently, both wheel 321 and wheel 351 are loose wheels through which no power is transmitted. Clutch point 304a or 304b is closed; this has no influence on the power curve in this 4th gear. For efficiency reasons, however, closing clutch point 304a is preferred in order to operate the hollow shaft 302 at a lower speed. Overall, it is possible to use this fourth gear as a 3rd or 5th gear by varying the gear ratio of gear stage 340.The order of gears 3 and 5 described here changes accordingly.

[0127] The power flow of the fifth gear of this 5-speed variant of the third embodiment is in Fig. 18. Clutch point 305a of clutch 305 is closed. Clutch point 304a of clutch 304 is closed. The drive power 4 is transmitted via the drive shaft 2 via the first gear stage 310 to the first intermediate shaft 301, via the fifth gear stage 350 to the hollow shaft 302, via the third gear stage 330 designed as a planetary stage to the axle differential 1 and then in a manner known per se to the wheel drive shafts 3a, 3b. By closing clutch point 305b of clutch 305, wheel 351 is an idler gear via which no power is transmitted. By closing clutch point 304a of clutch 304, the third gear stage 330 designed as a planetary stage rotates in a block and has a gear ratio = 1.

[0128] Fig. 19 shows a supplementary illustration of an isometric view of the first embodiment of the axle drive 100.

[0129] Finally, the following connection is noted: The axle differential 1, the drive shaft 2, the first intermediate shaft 101, 201, 301, the wheel drive shafts 3a, 3b, the gear ratios 110, 210, 310, 120, 220, 320, 130, 230, 330, 140, 240, 340, 150, 250, 350, as well as the pinions 111, 121, 131, 141, 151 and the gears 112, 132, 142, 152 are partially dimensioned and shaped differently in the embodiments shown. As the designations of the figures indicate, these are to be understood as schematic representations only. In this respect, it is quite conceivable that the components mentioned have the same or similar dimensions and shapes in order to increase the number of identical parts and the modularity of the gearbox kit.

[0130] Furthermore, it is conceivable that the axle differential 1 in all described embodiments has a differential lock 109, 209, 209 which can be moved into a closed position 109a in which the axle differential 1 is locked or bridged so that no speed inequality can occur between the motor vehicle wheels.

[0131] The invention is not limited to the preferred embodiments described above. Rather, a multitude of variants and modifications are possible which also make use of the inventive concept and therefore fall within the scope of protection. In particular, the invention also claims protection for the subject matter and features of the subclaims, independent of the claims referred to. In particular, the individual features of independent claim 1 are each disclosed independently of one another. In addition, the features of the subclaims are also disclosed independently of all features of independent claim 1. All ranges referred to herein are to be understood as disclosed in such a way that, as it were, all values ​​falling within the respective range are individually disclosed, e.g., also as preferred, narrower outer limits of the respective range. List of reference symbols 1 axle differential 2 drive shaft 3a, 3b Wheel drive shaft 4 Drive power from the electric motor 5 wheel drive power 6 Electric machine 100 First embodiment of the axle drive 100a basic module 101 First intermediate shaft of the first embodiment 102 Hollow shaft of the first embodiment 103 Second intermediate shaft of the first embodiment 104 First switching element, e.g. claw clutch 104a First coupling point of the first switching element 105 Second switching element, e.g. claw clutch 105a First coupling point of the second switching element 105b Second coupling point of the second switching element 107a First optional assembly 107b Second optional assembly 107c Third optional assembly 109 Transverse lock 109a Closed position of the transverse lock 110 First translation stage of the first embodiment 111 pinion of the first gear stage 112 First gear wheel 120 Second gear ratio of the first embodiment 121 pinion of the second gear stage 122 Wheel of the second gear stage 130 Third gear ratio of the first embodiment 131 pinion of the third gear stage 132 Wheel of the third gear stage 140 Fourth gear ratio of the first embodiment 141 pinion of the fourth gear stage 142 Wheel of the fourth gear ratio 150 Fifth gear ratio of the first embodiment 151 pinion of the fifth gear stage 152 Wheel of the fifth gear stage 200 First variant of the second embodiment of the axle drive 200a basic module 201 First intermediate shaft of the first variant of the second embodiment 202 Hollow shaft of the first variant of the second embodiment 203 Second intermediate shaft of the first variant of the second embodiment 204 First switching element, e.g. claw clutch 204a First coupling point of the first switching element 204b Second coupling point of the first switching element 205 Second switching element, e.g. claw clutch 205a First coupling point of the second switching element 205b Second coupling point of the second switching element 206 Third switching element, e.g. claw clutch 206a First coupling point of the third switching element 206b Second coupling point of the third switching element 207a First optional assembly 207b Second optional assembly 207c Third optional assembly 209 Transverse lock 209a Closed position of the transverse lock 210 First gear ratio of the first variant of the second embodiment 211 pinion of the first gear stage 212 First gear wheel 220 second gear ratio of the first variant of the second embodiment 221 pinion of the second gear stage 222 Wheel of the second gear stage 230 Third gear ratio of the second first variant of the embodiment 231 pinion of the third gear stage 232 Wheel of the third gear stage 240 Fourth gear ratio of the second first variant of the embodiment 241 pinion of the fourth gear stage 242 Wheel of the fourth gear ratio 250 Fifth gear ratio of the first variant of the second embodiment 251 pinion of the fifth gear stage 252 Wheel of the fifth gear stage 300 second variant of the second embodiment of the axle drive 300a basic module 301 First intermediate shaft of the second variant of the second embodiment 302 Hollow shaft of the third embodiment 304 First switching element, e.g. claw clutch 304a First coupling point of the first switching element 304b Second coupling point of the first switching element 305 Second switching element, e.g. claw clutch 305a First coupling point of the second switching element 305b Second coupling point of the second switching element 306 Third switching element, e.g. claw clutch 306a First coupling point of the third switching element 306b Second coupling point of the third switching element 307a First optional assembly 307b Second optional assembly 307c Third optional assembly 307d Fourth optional assembly 309 transverse lock 309a Closed position of the transverse lock 310 First gear ratio of the second variant of the second embodiment 311 pinion of the first gear stage 312 First gear wheel 320 Second gear ratio of the second variant of the second embodiment 321 pinion of the second gear stage 322 Wheel of the second gear stage 330 Third gear stage of the second variant of the second embodiment, designed as a planetary stage 331 Sun pinion of the third gear stage 332 Planetary gear of the third gear stage 333 Ring gear of the third gear stage 334 Planet carrier of the third gear ratio 335 Planet carrier web of the third gear ratio 336 differential housing 340 Fourth gear ratio of the second variant of the second embodiment 341 pinion of the fourth gear stage 342 Wheel of the fourth gear ratio 350 Fifth gear ratio of the second variant of the second embodiment 351 pinion of the fifth gear stage 352 Wheel of the fifth gear stage 400 axle drive device 500 Motor vehicle, e.g.: Commercial vehicle 600 Modular transmission system D Axial direction

Claims

[1] Axle transmission (100; 200; 300) for an axle, preferably for an electrically driven axle, of a motor vehicle, for example a commercial vehicle, which has a basic module (100a; 200a, 300a) comprising: an axle differential (1), preferably an axle differential lockable with a differential lock, and two wheel drive shafts (3a, 3b) driven by the axle differential (1); a drive shaft (2) arranged parallel to the wheel drive shafts (3a, 3b); a first intermediate shaft (101; 201; 301) arranged parallel to the wheel drive shafts (3a, 3b); a hollow shaft (102; 202; 302) arranged coaxially with the wheel drive shafts (3a, 3b); and at least one first gear ratio stage (110; 210; 310) and one second gear ratio stage (120; 220; 320) arranged to drive the drive shaft (2) to the axle differential (1) via the first intermediate shaft (101; 201; 301) and the hollow shaft (102; 202; 302), wherein the drive shaft (2) is connected to the first intermediate shaft (101; 201; 301) via the first gear stage (110; 210; 310), the first intermediate shaft (101; 201; 301) is fixedly connected or switchably connectable to the hollow shaft (102; 202; 302) via the second gear stage (120; 220; 320); and the first intermediate shaft (101; 201; 301) is arranged between the drive shaft (2) and the hollow shaft (102; 202; 302); and one of the wheel drive shafts (3a, 3b) is arranged at least partially within the hollow shaft (102, 202, 302), characterized by a second intermediate shaft (103) arranged parallel to the wheel drive shafts (3a, 3b) and serving as a countershaft, which is arranged on an opposite side of the hollow shaft (102) with respect to the first intermediate shaft (101) and which is drivingly connected to the axle differential (1) via a fourth gear stage (140); and a third transmission stage (130) arranged to drive the hollow shaft (102) to the second intermediate shaft (103). [2] Axle transmission according to claim 1, wherein the axle transmission is designed as a 1-speed transmission, wherein the drive shaft (2) is drivingly connected to the axle differential (1) via the two intermediate shafts (101, 103), the hollow shaft (102) and the transmission stages (110, 120, 130, 140). [3] Axle transmission (100) according to claim 1, wherein the axle transmission is designed as a multi-speed transmission, preferably an automated multi-speed transmission, further comprising a first switching element (104) arranged for selectively connecting the hollow shaft (102) to the axle differential (1) in a rotationally fixed manner; and a second switching element (105) which is arranged (130) for the selective driving connection of the hollow shaft (102) to the second intermediate shaft (103) via the third transmission stage. [4] Axle transmission according to claim 3, wherein the axle transmission is designed as a two-speed transmission, wherein in the lowest gear the hollow shaft (102) is drivingly connected to the axle differential (1) via the third and fourth gear ratio (130, 140), the second shifting element (105) and the second intermediate shaft (103) and in the highest gear the hollow shaft (102) is non-rotatably connected to the axle differential (1) directly via the first shifting element (104). [5] Axle transmission (100) according to claim 3, wherein the axle transmission is designed as a three-speed transmission, further comprising a fifth gear stage (150) arranged for drivingly connecting the hollow shaft (102) to the second intermediate shaft (103). [6] Axle transmission (100) according to claim 5, wherein the hollow shaft (102) is connected to the axle differential (1) a) in the lowest two gears a1) optionally either via the fourth and third gear ratios (140, 130) or via the fourth and fifth gear ratios (140, 150) and a2) the second intermediate shaft (103) is drivingly connected, and b) in the highest gear is connected in a rotationally fixed manner directly via the first switching element (104). [7] Axle transmission (100) according to one of the preceding claims, wherein the first and second gear ratios (110, 120) are arranged on the same side of the axle differential (1) - viewed in the axial direction - as the third and / or fifth gear ratios (130, 150); and / or the drive shaft (2) is arranged on the same side of the axle differential (1) - seen in the axial direction - as the hollow shaft (102). [8] Axle transmission (100) according to one of the preceding claims, wherein a1) the third gear ratio stage (130) is designed as a spur gear stage, wherein a loose gear (132) of the third spur gear stage can be connected in a rotationally fixed manner to the second intermediate shaft via the second shift element (105), and / or a2) the fifth gear ratio stage (150) is designed as a spur gear stage, wherein a loose gear (152) of the fifth spur gear stage can be connected in a rotationally fixed manner to the second intermediate shaft (103) via the second shift element (105); and / or b) the first and / or second switching element (104, 105) is designed as a positive-locking switching element, preferably as a claw clutch. [9] Axle transmission (200; 300) for an axle, preferably for an electrically driven axle, of a motor vehicle, for example a commercial vehicle, which has a basic module (100a; 200a, 300a) comprising: an axle differential (1), preferably an axle differential lockable with a differential lock, and two wheel drive shafts (3a, 3b) driven by the axle differential (1); a drive shaft (2) arranged parallel to the wheel drive shafts (3a, 3b); a first intermediate shaft (101; 201; 301) arranged parallel to the wheel drive shafts (3a, 3b); a hollow shaft (102; 202; 302) arranged coaxially with the wheel drive shafts (3a, 3b); and at least one first gear ratio stage (110; 210; 310) and one second gear ratio stage (120; 220; 320) arranged to drive the drive shaft (2) to the axle differential (1) via the first intermediate shaft (101; 201; 301) and the hollow shaft (102; 202; 302), wherein the drive shaft (2) is connected to the first intermediate shaft (101; 201; 301) via the first gear stage (110; 210; 310), the first intermediate shaft (101; 201; 301) is fixedly connected or switchably connectable to the hollow shaft (102; 202; 302) via the second gear stage (120; 220; 320); and the first intermediate shaft (101; 201; 301) is arranged between the drive shaft (2) and the hollow shaft (102; 202; 302); and one of the wheel drive shafts (3a, 3b) is arranged at least partially within the hollow shaft (102, 202, 302), characterized bythat the first gear ratio (210; 310) and the second gear ratio (220; 320) - seen in the axial direction - are arranged on different sides of the axle differential (1), wherein the axle transmission (200) further comprises: a second intermediate shaft (203) arranged parallel to the wheel drive shafts (3a, 3b) and serving as a countershaft, which is arranged on an opposite side of the hollow shaft (202) with respect to the first intermediate shaft (201) and which is drivingly connected to the axle differential (1), preferably via a fourth gear ratio stage (240); and a third transmission stage (230) which is arranged for drivingly connecting the hollow shaft (202) to the second intermediate shaft (203) and is preferably designed as a switchable spur gear stage. [10] Axle transmission (200) according to claim 9, further comprising a first switching element (204) arranged for selectively connecting the hollow shaft (202) to the axle differential (1) in a rotationally fixed manner. [11] Axle transmission (200) according to claim 10, which is designed as a multi-speed transmission, wherein, in order to realize the highest gear, the hollow shaft (202) is connected in a rotationally fixed manner to the axle differential (1) via the first switching element (204) and the second intermediate shaft (203) is not drivingly connected to the hollow shaft (202). [12] Axle transmission (300) according to claim 9, further comprising a third gear ratio stage arranged for drivingly connecting the hollow shaft (302) to the axle differential (1), wherein the third gear ratio stage is realized via a planetary gear (330) whose sun shaft corresponds to the hollow shaft (302) and a planet carrier of the planetary gear (330) is part of a housing of the axle differential (1) or is fixedly connected to the housing of the axle differential (1). [13] Axle transmission (300) according to claim 12, which is designed as a multi-speed transmission, wherein the planetary gear (330) is switched into a block circuit to realize the highest gear. [14] Axle transmission (300) according to claim 12 or 13, further comprising a fourth gear ratio stage (340) which is arranged for drivingly connecting the first intermediate shaft (301) and the axle differential (1), and is preferably designed as a switchable spur gear stage. [15] Axle transmission (200; 300) according to one of claims 9 to 14, further comprising a fifth gear ratio stage (250; 350) which is arranged for drivingly connecting the first intermediate shaft (201; 301) and the hollow shaft (202; 302) and is preferably designed as a switchable spur gear stage. [16] Axle transmission (200; 300) according to one of claims 9 to 15, wherein the first gear ratio stage (210; 310) - viewed in the axial direction - is arranged on a different side of the axle differential than the a) third gear ratio (230; 330) in an axle transmission of claims 10 to 15; and / or b) fifth gear ratio (250; 350) in an axle transmission according to claim 15. [17] Axle transmission (200 300) according to one of claims 9 to 16, wherein the axle transmission is designed as a multi-speed transmission, preferably an automated multi-speed transmission, and a plurality of shifting elements (204, 205, 206; 304, 305, 306) are provided, preferably each designed as a positive shifting element, more preferably as a claw clutch, which are arranged for the selective driving connection of the first intermediate shaft (201; 301) and the hollow shaft (202; 302) via the second transmission stage (220; 320). [18] Axle transmission (200 300) according to one of claims 9 to 11, wherein the axle transmission is designed as a multi-speed transmission, preferably an automated multi-speed transmission, and a plurality of shifting elements (204, 205, 206; 304, 305, 306) are provided, preferably each designed as a positive shifting element, more preferably as a claw clutch, which are arranged for the selective driving connection of the hollow shaft (202; 302) and the second intermediate shaft (203; 303) via the third gear ratio stage (230) [19] Axle transmission (200 300) according to claim 14, wherein the axle transmission is designed as a multi-speed transmission, preferably an automated multi-speed transmission, and a plurality of shifting elements (204, 205, 206; 304, 305, 306) are provided, preferably each designed as a positive shifting element, more preferably as a claw clutch, which are arranged for the selective driving connection of the first intermediate shaft (301) and the axle differential (1) via the fourth gear ratio stage (340). [20] Axle transmission (200 300) according to one of claims 13 to 15, wherein the axle transmission is designed as a multi-speed transmission, preferably an automated multi-speed transmission, and a plurality of shifting elements (204, 205, 206; 304, 305, 306) are provided, preferably each designed as a positive shifting element, more preferably as a claw clutch, which are arranged for the selective driving connection of the hollow shaft (302) to the axle differential (1) via the planetary gear (330). [21] Axle drive device (400) for an electrically driven axle of a commercial vehicle, comprising the axle drive (100; 200; 300) according to one of the preceding claims; and an electric machine (6) having the drive shaft (2) arranged parallel to the wheel drive shafts. [22] Axle drive device according to claim 21, further comprising a rigid axle body of a rigid axle of the commercial vehicle, in which the axle transmission and the electric machine are integrated. [23] Axle drive device according to claim 21 or 22, wherein the axle transmission is designed as a multi-speed transmission, wherein the drive device is designed to synchronize a control of switching elements for switching the gear ratios in dependence on the control of the electric machine. [24] Motor vehicle (500), preferably a commercial vehicle, comprising an axle transmission according to one of claims 1 to 20 or an axle drive device according to one of claims 21 to 23. [25] Modular transmission kit (600) for a motor vehicle, preferably a commercial vehicle, comprising a plurality of axle transmissions (100; 200; 300) according to one of the preceding claims 1 to 20, each of which differs in its number of gears. [26] Modular transmission kit (600) according to claim 25, which comprises exclusively axle transmissions designed either according to one of claims 1 to 8 or according to one of claims 9 to 20. [27] Modular transmission system (600) according to claim 26, wherein the basic module is of identical construction for all axle transmissions and / or is made of identical parts. [28] Modular transmission system (600) according to claim 26 or 27, wherein in all axle drives of the modular transmission system a1) an axial distance between the drive shaft (2) and the first intermediate shaft is equal, a2) an axial distance between the hollow shaft and the first intermediate shaft is equal, and a3) the centre distance between the hollow shaft and the second intermediate shaft, if any, is the same; and / or b) storage locations are the same; and / or c) the positioning and ratio of the axle differential and / or the housing parts of the axle differential are the same. [29] Modular axle drive device kit for a motor vehicle, preferably a commercial vehicle, comprising a plurality of different axle drive devices according to one of claims 21 to 23, each having an axle transmission derived from the modular transmission kit (600) according to one of claims 25 to 28. [30] Modular axle drive device according to claim 29, wherein the axle body is identical in all axle drive devices.

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