WO2024074312A1

WO2024074312A1 - Transmission for a vehicle, and powertrain comprising such a transmission

Info

Publication number: WO2024074312A1
Application number: PCT/EP2023/076039
Authority: WO
Inventors: Stefan Beck; Matthias Reisch; Eckhardt LÜBKE; Domenico Bartilucci; Tamas Gyarmati
Original assignee: Zf Friedrichshafen Ag
Priority date: 2022-10-06
Filing date: 2023-09-21
Publication date: 2024-04-11
Also published as: DE102022210571A1

Abstract

The invention relates to a transmission (3) for the powertrain (2) of a vehicle (1), comprising an input shaft (4) which has a first rotational axis (15), a first output shaft (5), a second output shaft (6), and a differential (7) which is effectively arranged between the input shaft (4) and the two output shafts (5, 6), wherein the differential (7) comprises a first planetary gear set (8), which comprises multiple gear set elements, and at least one second planetary gear set (9), which is operatively connected to the first planetary gear set and comprises multiple gear set elements, and a first output torque can be transmitted to the first output shaft (5) at least indirectly by means of the first planetary gear set (8). A support torque of the first planetary gear set (8) can be converted at least in the second planetary gear set (9) such that a second output torque which corresponds to the first output torque can be transmitted to the second output shaft (5). One of the planetary gear sets (8, 9) has at least one planetary gear (28b, 28c) with a second rotational axis (16), and the second rotational axis (16) of each planetary gear (28b, 28c) is diagonal to the first rotational axis (15) of the input shaft (4). The invention additionally relates to a powertrain (2) comprising such a transmission (3).

Description

Transmission for a vehicle and drive train with such a transmission

The invention relates to a transmission for a drive train of a vehicle and to a drive train with such a transmission.

DE 10 2013 215 877 B4 discloses an epicyclic gear for branching the drive power applied to a power input to a first and a second power output in conjunction with a reduction of the output speed to a speed level below the drive speed at the power input. The epicyclic gear has a first planetary stage, which comprises a first sun gear, a first planetary set, a first planetary carrier and a first ring gear. The epicyclic gear also has a second planetary stage, which comprises a second sun gear, a second planetary set, a second planetary carrier and a second ring gear. The epicyclic gear also has a third planetary stage, which comprises a third sun gear, a third planetary set, a third planetary carrier and a third ring gear. The first sun gear functions as the power input, with the first planetary carrier being connected to the second sun gear in a rotationally fixed manner. The second planet carrier is fixed in a stationary manner, the first ring gear is connected to the third sun gear in a rotationally fixed manner and the third ring gear is connected to the second planet carrier in a rotationally fixed manner. A first power output is achieved via the third planetary stage, with a second power output being achieved via the second ring gear of the second planetary stage.

The object of the present invention is to propose a space-saving and efficient transmission for a drive train of a vehicle that enables high levels of efficiency. The object is achieved by a transmission with the features of independent patent claim 1 and by a drive train with the features of patent claim 15. Advantageous embodiments are the subject of the subclaims, the following description and the figures.

A transmission according to the invention for a drive train of a vehicle comprises an input shaft having a first axis of rotation, a first output shaft, a second output shaft, wherein between the input shaft and the two output shafts a first planetary gear set with a plurality of gear set elements and at least one second planetary gear set operatively connected thereto with a plurality of gear set elements are operatively arranged, wherein one of the planetary gear sets has at least one planetary gear with a second axis of rotation, wherein the second axis of rotation of the respective planetary gear is arranged obliquely to the first axis of rotation of the input shaft.

The first axis of rotation is to be understood as the drive axis of the transmission. The respective planetary gear with the second axis of rotation is arranged at an angle to the first axis of rotation. “Arranged at an angle” is to be understood as a non-parallel arrangement of the first to the second axis of rotation. Any arrangement of the second axis of rotation that is neither parallel nor exactly perpendicular to the first axis of rotation is therefore to be understood as an oblique arrangement of the axes of rotation. If one axis of rotation is arranged at an angle to the other, this essentially includes two alternatives. On the one hand, an oblique arrangement of the axes of rotation exists if the angle between the axes of rotation is arbitrary but not 0°, i.e. the axes are not parallel to one another, and also not 90°, i.e. the axes are not perpendicular to one another. The axes of rotation meet at a common intersection point. On the other hand, within the scope of this invention, an oblique arrangement of the rotation axes is also to be understood as meaning that the rotation axes are skewed to one another, i.e. the axes do not lie in a common plane and therefore do not have a common intersection point.

The input shaft rotates about the first rotation axis. Both planetary gear sets each have at least one planetary gear with an associated rotation axis. In a first alternative, the rotation axis of the respective planetary gear of the first planetary gear set can be the second rotation axis in the sense of the invention, while the rotation axis of the respective planetary gear of the second planetary gear set is arranged axially parallel to the first rotation axis of the input shaft. In a second alternative, the rotation axis of the respective planetary gear of the second planetary gear set can be the second rotation axis in the sense of the invention. while the rotation axis of the respective planetary gear of the first planetary gear set is arranged parallel to the first rotation axis of the input shaft. Regardless of which alternative is selected, the second rotation axis is arranged at an angle to the first rotation axis.

By slanting the planetary axis or the respective second rotation axis to the first rotation axis, it is possible to design the corresponding planetary gear set with a small stationary ratio without the planetary gear diameter necessarily having to be small. This means that there is enough space inside the respective planetary gear that lies on the second rotation axis to accommodate a sufficiently dimensioned bearing for the respective planetary gear.

This type of transmission can achieve high gear ratios while maintaining high power density and efficiency. The installation space required for the transmission can also be reduced. The drive torque applied to the input shaft is converted by the differential into two output torques of approximately equal magnitude that are greater than the drive torque.

The input shaft is preferably designed to be at least indirectly connected in a rotationally fixed manner to a drive shaft of a drive unit. The drive unit generates a drive power that is transmitted to the input shaft via the drive shaft. The drive shaft of the drive unit can be connected in a rotationally fixed manner to the input shaft. Alternatively, the drive shaft and the input shaft are a connected or one-piece component. Depending on the design of the drive train, two or more input shafts can also be provided, in particular if the drive train is a hybridized drive train and therefore two or more drive units are provided.

The input shaft is preferably designed as a hollow shaft. As a result, one of the output shafts, preferably the first output shaft, can be guided axially through the input shaft. Preferably, one of the output shafts, in particular the first output shaft, through the gearbox and, if necessary, through the drive unit of the drive train. The respective output shaft is thus guided "inline" through the gearbox, so to speak, in order to transmit drive power to the wheel that is operatively connected to it. In this case, the output shafts are advantageously arranged coaxially to one another. The coaxial arrangement of the output shafts enables a radially narrow design of the gearbox to be achieved. A parallel, offset arrangement of the output shafts is also conceivable.

A "shaft" is a rotatable component of the transmission, via which the associated components of the transmission are connected to one another in a rotationally fixed manner. The respective shaft can connect the components axially or radially, or both axially and radially. A shaft is not exclusively understood to mean, for example, a cylindrical, rotatably mounted machine element for transmitting torque, but rather also general connecting elements that connect individual components or elements to one another, in particular connecting elements that connect several elements to one another in a rotationally fixed manner.

The fact that two components of the transmission are rotationally "connected" or "coupled" or "connected to one another" means, in the sense of the invention, a permanent coupling of these components so that they cannot rotate independently of one another. This is therefore to be understood as a permanent rotary connection. In particular, no switching element is provided between these components, which can be elements of the differential and/or shafts and/or a rotationally fixed component of the transmission, but rather the corresponding components are firmly coupled to one another. A torsionally elastic connection between two components is also understood as fixed or rotationally fixed.

Preferably, the first planetary gear set and the at least second planetary gear set are associated with a differential, wherein a first output torque can be transmitted to the first output shaft at least indirectly by means of the first planetary gear set, wherein a support torque of the first planetary gear set can be converted at least in the second planetary gear set in such a way that a first output torque corresponding second output torque is transferable to the second output shaft, wherein a first gear set element of the first planetary gear set is operatively connected to the input shaft, wherein a second gear set element of the first planetary gear set is at least indirectly connected in a rotationally fixed manner to the first output shaft, wherein a third gear set element of the first planetary gear set is at least indirectly connected in a rotationally fixed manner to a first gear set element of the second planetary gear set, wherein a second gear set element of the second planetary gear set is connected in a rotationally fixed manner to a stationary component, wherein a third gear set element of the second planetary gear set is connected in a rotationally fixed manner to the second output shaft.

In such a transmission, the sums of both wheel torques are not combined or combined to form a common axle torque in a rotating component. Rather, the drive power introduced into the input shaft is divided in the differential and passed on to the output shafts connected to it in accordance with the design and connection of the planetary gear sets. This means that the components of the differential can be made slimmer due to the respective, comparatively small torque. Furthermore, there is a reduction in the number of components and a saving in weight. A transmission is therefore provided that, by means of the integral differential, can perform the two functions of torque conversion and torque distribution, which were previously solved by two separate components, using a single integral component. The invention is therefore a combined transmission and differential transmission that realizes torque conversion on the one hand and torque distribution to the output shafts on the other, while also realizing power splitting. With such a transmission, high transmission ratios can be realized, in particular of i > 10.

The differential is to be understood as an integral differential, whereby the transmission is consequently a differential transmission. In the context of this invention, an integral differential is to be understood as a differential with a first planetary gear set and at least one further planetary gear set operatively connected to the first planetary gear set. For a differential with exactly two planetary gear sets, the first planetary gear set is connected to the input shaft, to the second planetary gear set and at least indirectly to the first output shaft. The second planetary gear set is connected to the second output shaft. Using such an integral differential, the input torque on the input shaft can be changed and divided or transferred to the two output shafts in a defined ratio. Preferably, the input torque is transferred 50% each, i.e. half, to the output shafts. The differential therefore has no rotating component to which the sum of the two output torques is applied. In other words, the creation of a total torque is prevented. In addition, when the output shafts have identical output speeds, the differential has no gears rotating in the block or rotating without a rolling motion. Therefore, regardless of the output speeds of the output shafts, there is always a relative movement of the meshing components of the differential.

For a differential with exactly three planetary gear sets, one of the planetary gear sets is arranged on the input side and is drive-connected to the other two planetary gear sets, via which the output is transmitted to the first and/or second output shaft. According to one embodiment, the first planetary gear set is drive-connected to the input shaft and to the second and third planetary gear sets, with the second planetary gear set additionally being drive-connected to the second output shaft and being supported on the housing via one of its gear set elements, and with the third planetary gear set additionally being drive-connected to the first output shaft and the second output shaft. According to an alternative embodiment, the first planetary gear set is drive-connected to the first output shaft and to the second and third planetary gear sets, with the second planetary gear set additionally being drive-connected to the second output shaft and being supported on the housing via one of its gear set elements, and with the third planetary gear set additionally being drive-connected to the input shaft. According to another alternative design, the first planetary gear set is connected via one of its gear set elements supported on the housing and drive-connected to the second and third planetary gear sets, the second planetary gear set additionally drive-connected to the input shaft and the second output shaft, and the third planetary gear set additionally drive-connected to the first output shaft. According to a further alternative embodiment, the first planetary gear set is drive-connected to the input shaft and to the second and third planetary gear sets, the second planetary gear set additionally drive-connected to the first output shaft and supported on the housing via one of its gear set elements, and the third planetary gear set additionally drive-connected to the second output shaft and also supported on the housing via one of its gear set elements. Irrespective of the connection of the planetary gear set elements to one another and of the assignment of the planetary gear sets to the input shaft, the output shafts and the housing connection, the following applies to all examples: the planetary gear or gears of one of the three planetary gear sets is or are located on a second axis of rotation which is or are arranged obliquely to the first axis of rotation on which the input shaft is located.

Using such an integral differential with three planetary gear sets, the input torque on the input shaft can also be changed and divided or transferred to the two output shafts in a defined ratio. Preferably, the input torque is transferred 50% each, i.e. half, to the output shafts. The differential has no rotating component to which the sum of the two output torques is applied, so that the creation of a total torque is prevented. Such a differential has gears that rotate in the block or rotate without rolling motion when the output shafts have identical output speeds, namely on the gear set elements of the second or third planetary gear set, which are directly connected to the output shafts. Such a differential is to be understood as an asymmetrical differential.

The output shafts of the transmission are designed in particular to be operatively connected to a wheel of the vehicle. The respective output shaft can be connected to the associated wheel directly or indirectly, i.e. via a joint and/or a wheel hub, for example. The differential is therefore designed as a planetary gear with at least two planetary gear sets and the gear set elements sun gear, ring gear and several planetary gears guided by a planet carrier on a circular path around the sun gear. A "planetary gear set" is to be understood as a unit with several gear set elements in the form of a sun gear, a ring gear and a planet carrier, with at least one planetary gear guided by the planet carrier on a circular path around the sun gear, preferably several planetary gears, being rotatably arranged on the planet carrier, with the planet gear or the planet gears meshing with the ring gear and/or the sun gear depending on the design of the respective planetary gear set. It is conceivable that the differential has three or more planetary gear sets that are operatively connected to one another.

The terms sun gear, ring gear and planetary gears are also used for planetary gear sets with planetary gears or planetary axes that are inclined in relation to the input shaft or the first axis of rotation or second axes of rotation, whereby these are bevel gears. Analogous to the planetary gear set with a parallel planetary axis, in particular in accordance with the explanations in the previous paragraph, the larger of the bevel gears is referred to as the ring gear and the smaller of the bevel gears is referred to as the sun gear.

A stationary component is understood to be a component of the transmission that is rotationally and axially fixed, for example the transmission housing. The stationary component can therefore be arranged so that it is fixed to the housing. The term "fixed to the housing" is to be understood to mean that no relative movement takes place or can take place between the respective gear set element fixed to the housing and the stationary component of the transmission.

In this case, the transmission has five shafts, namely the input shaft, the first output shaft, the second output shaft, a coupling shaft that at least indirectly connects the third gear set element of the first planetary gear set in a rotationally fixed manner to the first gear set element of the second planetary gear set, and a shaft for connecting the second gear set element of the second planetary gear set to the stationary component. Preferably, the third gear set element of the first planetary gear set is connected in a rotationally fixed manner to the first gear set element of the second planetary gear set via a coupling shaft. In other words, the planetary gear sets are operatively connected to one another via the coupling shaft.

Preferably, the second rotation axis has a common intersection point with the first rotation axis. The second rotation axis is only arranged at an angle to the first rotation axis. The first and respective second rotation axes therefore lie in a common plane.

The planetary gear set, which has the respective planetary gear that lies on the second axis of rotation, can in this case be designed as an angular gear in planetary design, in particular as a bevel gear. The gears of the gear set elements of this planetary gear set are preferably designed as straight gears, helical gears, curved gears or spiral gears. It has been found that curved or spiral gears are advantageous for transmitting the drive torque.

Alternatively, the second rotation axis is arranged skewed to the first rotation axis. In this case, the first and respective second rotation axes do not have a common intersection point and are not arranged parallel or exactly perpendicular to each other.

The planetary gear set, which has the respective planetary gear that lies on the second axis of rotation, can in this case be designed as a hypoid gear in planetary design, in particular as a bevel gear screw gear. The gears of the gear set elements of this planetary gear set are preferably designed as straight gears, helical gears, curved gears or spiral gears. It has been found that curved or spiral gears are advantageous for transmitting the drive torque. Preferably, the first planetary gear set is arranged at least partially radially within the second planetary gear set. By arranging the first planetary gear set at least partially radially within the second planetary gear set according to the first aspect of the invention, a radially nested design of the integral differential is realized. In other words, the gear set elements of the first and second planetary gear sets are arranged axially in a common plane. The first and second planetary gear sets are therefore arranged essentially in a common gear plane, which means that the transmission is axially short and can therefore be designed to be particularly compact. The first and second planetary gear sets are arranged one above the other when viewed radially. It is also conceivable that the first and second planetary gear sets are not arranged in a common plane, but that the first planetary gear set is arranged offset in the axial direction to the second planetary gear set.

Preferably, the input shaft and the output shafts have the same direction of rotation. The advantage is that a lower transmission support torque is applied to the second gear set element of the second planetary gear set or to the component via which the second gear set element of the second planetary gear set is supported on the stationary component.

Alternatively, the input shaft rotates in a first direction of rotation that is opposite to a second direction of rotation of the output shafts. When we talk about the direction of rotation of the output shafts, we mean that they rotate in the same direction. Of course, as with other known differential gears, operating states can be imagined and represented in which one output shaft rotates in a first direction of rotation, for example forwards, and the other output shaft rotates in a second direction of rotation that is opposite to this, i.e. backwards.

According to one embodiment, the first gear set element of the first planetary gear set is connected to the input shaft in a rotationally fixed manner. Alternatively, a In this sense, a gear ratio is arranged between the first input shaft and the first gear set element of the first planetary gear set. The gear ratio is connected upstream of the first planetary gear set of the differential. The gear ratio is to be understood as a pre-mounted group that is intended to increase a gear ratio of the transmission.

The transmission stage can be designed as a planetary gear transmission in the form of a planetary gear with at least one third planetary gear set and is connected upstream of the integral differential. The planetary gear set of the transmission stage has several gear set elements in the form of a sun gear, a ring gear and a planet carrier, with at least one planet gear, preferably several planet gears, being rotatably arranged on the planet carrier and guided by the planet carrier on a circular path around the sun gear, with the planet gear or the planet gears meshing with the ring gear and/or the sun gear depending on the design of the respective planetary gear set.

A first gear set element of the planetary gear set of the transmission stage is firmly connected to the stationary component, which can be the transmission housing, a second gear set element of the planetary gear set of the transmission stage is connected in a rotationally fixed manner to the drive side of the transmission, in particular the input shaft, and a third gear set element of the planetary gear set of the transmission stage is connected in a rotationally fixed manner to the input side of the differential, in particular to the first gear set element of the first planetary gear set. It is conceivable that the transmission stage designed as an epicyclic gear comprises a fourth or further planetary gear sets.

Alternatively, the transmission stage is designed as a spur gear stage. The spur gear stage can be designed as a single or multi-stage, i.e. with gears on intermediate shafts. In the case of a spur gear stage, the drive or a drive shaft, be it a rotor shaft of an electric machine or a crankshaft of an internal combustion engine, is arranged axially parallel to the input shaft of the transmission. In a further alternative embodiment of the transmission, a multi-speed transmission is arranged between the first input shaft and the first gear set element of the first planetary gear set. The multi-speed transmission can be an epicyclic gear transmission in the form of a planetary gear with at least a third planetary gear set, analogous to the gear ratio, and is connected upstream of the integral differential. One of the gear set elements of the third planetary gear set can, for example, be connected in a rotationally fixed manner to another of the gear set elements of the same planetary gear set via a first switching element in order to achieve a blocking of the third planetary gear set. A further switching element can be provided to connect one of the gear set elements in a rotationally fixed manner to the stationary component, in particular to the transmission housing. The advantage of an upstream multi-speed transmission is, among other things, that high output torques and a high final speed are possible. According to one embodiment, the multi-speed transmission is a 2-speed transmission.

Preferably, a switching element for transmitting torque between the output shafts is arranged between the first output shaft and the second output shaft. The switching element therefore serves as a differential lock. The switching element can be designed as a positive or frictional switching element. A positive switching element achieves a rotationally fixed coupling of the two output shafts, whereby a frictional switching element makes it possible to regulate the torque transmission. The switching element can influence the driving dynamics of the vehicle.

In principle, the planetary gear sets of the transmission can be arranged in any order and can be operatively connected to one another in order to achieve a desired gear ratio with the transmission.

According to one embodiment, the first gear set element is a sun gear of the respective planetary gear set of the differential, the second gear set element is a planet carrier of the respective planetary gear set of the differential and the third gear set element is a ring gear of the respective planetary gear set of the differential. The The input shaft is thus rotationally connected to the sun gear of the first planetary gear set, the planet carrier of the first planetary gear set being at least indirectly rotationally connected to the first output shaft, and the ring gear of the first planetary gear set being at least indirectly rotationally connected to the sun gear of the second planetary gear set. In particular, the ring gear of the first planetary gear set is rotationally connected to the sun gear of the second planetary gear set via a coupling shaft. The input shaft and the sun gear of the first planetary gear set can be designed as one piece, provided that no other transmission components or component groups are effectively arranged between the input shaft. Furthermore, in this sense the planet carrier of the second planetary gear set is fixed in place, for example on a housing of the transmission, the ring gear of the second planetary gear set being at least indirectly rotationally connected to the second output shaft.

According to an alternative embodiment, the first gear set element of the first planetary gear set is a sun gear, the second gear set element of the first planetary gear set is a ring gear, and the third gear set element of the first planetary gear set is a planet carrier, the first gear set element of the second planetary gear set is a ring gear, the second gear set element of the second planetary gear set is a planet carrier, and the third gear set element of the second planetary gear set is a sun gear. The input shaft is thus connected in a rotationally fixed manner to the sun gear of the first planetary gear set, the ring gear of the first planetary gear set is at least indirectly connected in a rotationally fixed manner to the first output shaft, and the planet carrier of the first planetary gear set is at least indirectly connected in a rotationally fixed manner to the ring gear of the second planetary gear set. In particular, the planet carrier of the first planetary gear set is connected in a rotationally fixed manner to the ring gear of the second planetary gear set via a coupling shaft. The input shaft and the sun gear of the first planetary gear set can be designed as one piece, provided that no other transmission components or component groups are effectively arranged between the input shaft. Furthermore, in this sense, the planet carrier of the second planetary gear set is fixed in place, for example on the transmission housing, with the sun gear of the second planetary gear set being at least indirectly connected in a rotationally fixed manner to the second output shaft. The connection of the gear set elements between the planetary gear sets can be swapped as required depending on the gear ratio requirements. In other words, the connection of the gear set elements can be varied as required. Additional components, such as intermediate or coupling shafts, can also be arranged between the components mentioned, i.e. the gear set elements of the planetary gear sets of the differential.

One or more of the planetary gear sets are preferably designed as a minus planetary gear set or as a plus planetary gear set. A minus planetary gear set corresponds to a planetary gear set with a planet carrier on which first planetary gears are rotatably mounted, a sun gear and a ring gear, wherein the teeth of at least one of the planetary gears mesh with both the teeth of the sun gear and the teeth of the ring gear, whereby the ring gear and the sun gear rotate in opposite directions when the sun gear rotates with the web stationary. A plus planetary gear set differs from the minus planetary gear set in that the plus planetary gear set has first and second or inner and outer planetary gears which are rotatably mounted on the planet carrier. The teeth of the first or inner planetary gears mesh on the one hand with the teeth of the sun gear and on the other hand with the teeth of the second or outer planetary gears. The teeth of the outer planet gears also mesh with the teeth of the ring gear. This means that when the planet carrier is stationary, the ring gear and the sun gear rotate in the same direction.

When one or more of the planetary gear sets are designed as a plus planetary gear set, the connection between the planet carrier and the ring gear is swapped and the value of the stationary gear ratio is increased by 1. This is also possible in reverse if a minus planetary gear set is to be provided instead of a plus planetary gear set. Alternatively, it is also conceivable to design one or more planetary gear sets as stepped planetary gear sets. Each stepped planetary gear of the respective stepped planetary gear set preferably comprises a first gear with a second gear connected to it in a rotationally fixed manner, the first gear meshing with the sun gear and the second gear meshing with the ring gear, for example, or vice versa. These two gears can be connected to one another in a rotationally fixed manner, for example, via an intermediate shaft or a hollow shaft. In the case of a hollow shaft, this can be rotatably mounted on a bolt of the planet carrier. The two gears of the respective stepped planetary gear preferably have different diameters and numbers of teeth in order to set a transmission ratio. Compound planetary gear sets are also conceivable.

Preferably, the first output shaft is arranged radially inside the second output shaft in sections and is mounted so that it can rotate relative to it. The second output shaft is designed as a hollow shaft at least in sections, with the second output shaft spatially accommodating and mounting the first output shaft in the area designed as a hollow shaft. Depending on the size of the output shaft, the bearing can be a roller bearing, a needle bearing or a plain bearing. Other types of bearing are also conceivable.

According to one embodiment, the differential further comprises a third planetary gear set with several gear set elements. In other words, the differential has three planetary gear sets that are operatively connected to one another. The first planetary gear set is in this case operatively connected to the input shaft with a first gear set element, to the second planetary gear set with a second gear set element and to the third planetary gear set with a third gear set element. The housing is supported, for example, by a gear set element of the second planetary gear set, which is also operatively connected, in particular rotationally fixed, to another gear set element both to the second output shaft and to a gear set element of the third planetary gear set. The third planetary gear set also has a gear set element that is operatively connected, in particular rotationally fixed, to the first output shaft. The second and third planetary gear sets can also be swapped. In any case, the planetary gear or, if more than one is provided, several planetary gears of one of the planetary gear sets on a second axis of rotation which is arranged obliquely to the first axis of rotation of the input shaft.

The term "actively connected" refers to a non-switchable connection between two components, which is intended for the permanent transmission of drive power, in particular a speed and/or a torque. The connection can be made either directly, i.e. as a rotationally fixed connection, or via a fixed gear ratio. The connection can be made, for example, via a fixed shaft, a gearing, in particular a spur gearing, and/or a belt.

The term "at least indirectly" means that two components are (operatively) connected to one another via at least one other component that is arranged between the two components, or are directly and thus immediately connected to one another. Thus, further components that are operatively connected to the shaft or gear can be arranged between shafts or gears.

A drive train according to the invention for a vehicle comprises a transmission according to the previous embodiments. The transmission is operatively connected to a drive unit. The drive unit is preferably an electric machine, wherein the input shaft of the transmission is a rotor of the electric machine or is connected or coupled in a rotationally fixed manner to the rotor or a rotor shaft. The rotor is rotatably mounted relative to a stator of the electric machine that is fixed to the housing.

The electric machine is preferably connected to an accumulator that supplies the electric machine with electrical energy. Furthermore, the electric machine can preferably be controlled or regulated by power electronics. The drive unit can alternatively also be an internal combustion engine, in which case the input shaft is, for example, a crankshaft or is connected or coupled to the crankshaft in a rotationally fixed manner. Preferably, the drive unit is arranged coaxially to the integral differential. This means that an additional transmission from the input shaft to the rotor shaft or the rotor or the crankshaft of the drive unit is not required. One of the output shafts, preferably the first output shaft, is guided axially through the drive unit in this case.

Additional intermediate components can be arranged between the input shaft of the transmission and the drive unit, for example in the form of planetary gears, spur gears, chain drives, belt drives, angle drives, cardan shafts, torsion dampers, multi-speed transmissions or the like. Additional intermediate components can also be arranged between the respective output shaft and the wheel operatively connected to it, such as cardan shafts, transmission gears, spring and damping elements or the like.

The drive train according to the type described above can be used in a vehicle. The vehicle is preferably a motor vehicle, in particular an automobile (e.g. a passenger car weighing less than 3.51), bus or truck (bus and truck, for example, weighing more than 3.5 t). In particular, the vehicle is an electric vehicle or a hybrid vehicle. The vehicle comprises at least two axles, one of the axles forming an axle that can be driven by means of the drive train. The drive train according to the invention is effectively arranged on this drivable axle, the drive train transmitting a drive power of the drive unit to the wheels of this axle via the transmission according to the invention. It is also conceivable to provide such a drive train for each axle.

The drive train is preferably installed in a front-transverse design, so that the input shaft and the output shafts are essentially aligned transversely to the longitudinal direction of the vehicle. Alternatively, the drive train can be arranged at an angle to the longitudinal and transverse axes of the vehicle, with the output shafts being connected via corresponding joints to the wheels of the respective axle, which are arranged transversely to the longitudinal axis of the vehicle. The above definitions as well as explanations of technical effects, advantages and advantageous embodiments of the transmission according to the invention also apply mutatis mutandis to the drive train according to the invention, and vice versa.

In the following, several embodiments of the invention are explained in more detail with reference to the schematic drawings.

Fig. 1 is a highly schematic plan view of a vehicle with a drive train according to the invention and a transmission according to the invention according to a preferred embodiment, and

Fig. 2 is a highly schematic longitudinal section of the transmission according to the invention according to Fig. 1,

Fig. 3 is a highly schematic longitudinal section of the transmission according to the invention according to a second embodiment,

Fig. 4 is a highly schematic longitudinal section of the transmission according to the invention according to a third embodiment,

Fig. 5 is a highly schematic longitudinal section of the transmission according to the invention according to a fourth embodiment,

Fig. 6 is a highly schematic longitudinal section of the transmission according to the invention according to a fifth embodiment,

Fig. 7 is a highly schematic longitudinal section of the transmission according to the invention according to a sixth embodiment,

Fig. 8 is a highly schematic longitudinal section of the transmission according to the invention according to a seventh embodiment, Fig. 9 is a highly schematic longitudinal section of the transmission according to the invention according to an eighth embodiment,

Fig. 10 is a highly schematic longitudinal section of the transmission according to the invention according to a ninth embodiment,

Fig. 11 is a highly schematic longitudinal section of the transmission according to the invention according to a tenth embodiment,

Fig. 12 is a highly schematic longitudinal section of the transmission according to the invention according to an eleventh embodiment,

Fig. 13 is a highly schematic longitudinal section of the transmission according to the invention according to a twelfth embodiment,

Fig. 14 is a highly schematic longitudinal section of the transmission according to the invention according to a thirteenth embodiment,

Fig. 15 is a highly schematic longitudinal section of the transmission according to the invention according to a fourteenth embodiment, and

Fig. 16 is a highly schematic longitudinal section of the transmission according to the invention according to a fifteenth embodiment.

According to Fig. 1, a vehicle 1 with two axles 11a, 11b is shown, with a drive train 2 according to the invention being arranged on the first axle 11a in a drive-effective manner. The vehicle 1 is an electric vehicle here, with the drive of the vehicle 1 being purely electric. The first axle 11a can be either the front axle or the rear axle of the vehicle 1 and forms a driven axle of the vehicle 1. Here, the first axle 11a is the rear axle or the non-steerable axle of the vehicle 1. The drive train 2 comprises a drive unit 22 designed as an electric machine and a transmission 3 connected to it in a drive-effective manner, with the structure and arrangement of the transmission 3 being shown in the following figures. is explained in more detail. The structure of the drive unit 22 is not shown here. The drive unit 22 or electric machine in any case has an accumulator that supplies it with electrical energy, and power electronics for controlling and regulating the drive unit 22. By energizing a stator (not shown here), a rotor (also not shown here) that is arranged to rotate relative to the stator and which, as a drive shaft, is in turn connected in a rotationally fixed manner to the input shaft 4 of the transmission 3 shown in the following figures, is set in a rotary movement relative to the stator. The drive power of the drive unit 22 is fed into the transmission 3 via the input shaft 4 and there converted by a differential 7 and at least indirectly divided between a first output shaft 5 and a second output shaft 6. The drive unit 22 is arranged coaxially to the integral differential 7.

At the ends of the output shafts 5, 6, which are arranged coaxially to one another in this case, a wheel 18 is connected at least indirectly in order to drive the vehicle 1. Joints and wheel hubs can be arranged between the respective wheel 18 and the output shafts 5, 6 in order to compensate for any misalignment of the output shafts 5, 6. These are not shown or described in detail here.

The transmission 3 shown in Fig. 2 to Fig. 17 is a differential transmission. The output shafts 5, 6 are arranged coaxially to one another and extend in opposite directions towards the wheels 18 according to Fig. 1, the first output shaft 5 being guided axially through the transmission 3, in particular through the integral differential 7 and the drive unit 22.

According to Fig. 2 to Fig. 16, the integral differential 7 is assigned a first planetary gear set 8 with several gear set elements and a second planetary gear set 9 operatively connected thereto, also with several gear set elements. By means of the first planetary gear set 8, a first output torque can be transmitted to the first output shaft 5, wherein a support torque of the first planetary gear set 8 in the second planetary gear set 9 can be converted in such a way that a second output torque corresponding to the first output torque can be transmitted to the second output shaft 6. For all embodiments, the input shaft 4 and the output shafts 5, 6 can have the same direction of rotation. Alternatively, the input shaft 4 can rotate in a first direction of rotation that is opposite to a second direction of rotation of the output shafts 5, 6.

According to Fig. 2 to Fig. 8 and Fig. 11 to Fig. 15, on the first planetary gear set 8, the first gear set element is a first sun gear 25a, the second gear set element is a first planet carrier 26a and the third gear set element is a first ring gear 27a, wherein several first planet gears 28a are rotatably arranged on the first planet carrier 26a, which mesh with the first sun gear 25a and the first ring gear 27a. The first output shaft 5 is guided axially through the first sun gear 25a of the first planetary gear set 8. The first sun gear 25a is therefore designed as a ring gear and the input shaft 4 connected to it is designed as a hollow shaft. The first sun gear 25a sits firmly on the input shaft 4 or is connected to it in a rotationally fixed manner. The first sun gear 25a and the input shaft 4 are connected to one another in one piece. Furthermore, on the second planetary gear set 9, the first gear set element is a second sun gear 25b, the second gear set element is a second planet carrier 26b and the third gear set element is a second ring gear 27b, wherein a plurality of second planet gears 28b are rotatably arranged on the second planet carrier 26b, which are in tooth engagement with the second sun gear 25b and the second ring gear 27b.

According to Fig. 2 to Fig. 8 and Fig. 11 to Fig. 15, the first ring gear 27a of the first planetary gear set 8 is connected in a rotationally fixed manner to the second sun gear 25b of the second planetary gear set 9 via a coupling shaft 14. The second planet carrier 26b of the second planetary gear set 9 is supported in a housing-fixed manner on the stationary component 13, which in this case is the transmission housing. The second planet carrier 26b is connected in a rotationally fixed manner to the stationary component 13 via a shaft 20. The second ring gear 27b of the second planetary gear set 9 can be connected in a rotationally fixed manner to the second output shaft 6 via a coupling element or the like, which can be designed as a ring gear carrier. The first and second planetary gear sets 8, 9 are each designed as a minus planetary gear set and are nested radially and thus arranged in a common plane which runs perpendicular to the axis 11a. This saves axial installation space. The first planetary gear set 8 is arranged radially within the second planetary gear set 9.

According to Fig. 2 to Fig. 8 and Fig. 11 to Fig. 15, the input shaft 4 lies on a first rotation axis 15. The first rotation axis 15 forms the drive axis of the transmission 3. The first rotation axis 15 can be arranged coaxially or axially parallel to the first axis 11a. The rotation axes of the output shafts 5, 6 also lie on the first rotation axis 15. The output shafts 5, 6 are thus arranged coaxially to the input shaft 4. In this case, the drive axis is arranged coaxially to the output axis.

The first and second planetary gear sets 8, 9 are arranged coaxially to the input shaft 4 and to the first rotation axis 15, respectively. However, each of the conical second planetary gears 28b of the second planetary gear set 9 lies on an associated second rotation axis 16, with the respective second rotation axis 16 being arranged obliquely, i.e. at an angle, to the first rotation axis 15 of the input shaft 4. Each second planetary gear 18b thus rotates about its own second rotation axis 16, with all rotation axes 16 being arranged equally obliquely to the first rotation axis 15 of the input shaft 4. The second planetary gear 28b is formed as a ring gear. By slanting the respective second rotation axis 16, which is to be understood as the planetary axis, to the first rotation axis 15, it is possible to design the second planetary gear set 9 with a small stationary ratio without the planet diameter of the second planetary gears 28b necessarily having to be small. This means that there is sufficient space inside the respective second planetary gear 28b to accommodate a sufficiently dimensioned bearing for the respective planetary gear 28b. Depending on the available installation space, the first rotation axis 15 of the input shaft 4 and the second rotation axis 16 of the respective second planetary gear 28b can have a common intersection point X. Alternatively, the first rotation axis 15 of the input shaft 4 and the second rotation axis 16 of the respective second planetary gear 28b can be arranged at an angle to one another. In this case, the rotation axes 15, 16 are also arranged at an angle to one another, but do not have a common intersection point. The angle between the first and second rotation axes 15, 16 is either between 0° and 90° or between 90° and 180°. In any case, the rotation axes 15, 16 are neither exactly parallel nor exactly perpendicular to one another.

According to Fig. 2, the first planet gears 28a are arranged axially parallel to the first rotation axis 15 of the input shaft 4. The angle between the first and second rotation axes 15, 16 is here less than 90°.

The transmission 3 according to Fig. 3 differs from the embodiment according to Fig. 2 in that the second rotation axis 16 is tilted or inclined in the opposite direction. The angle between the first and second rotation axes 15, 16 is greater than 90° here. In this case, the gear set elements of the first and second planetary gear sets 8, 9 are arranged essentially within the second ring gear 27b of the second planetary gear set 9. With regard to the effects and advantages, reference is made to what has been said about Fig. 2. A transmission 3 according to Fig. 2 or Fig. 3 has a high degree of efficiency and requires little installation space. In addition, specific installation space requirements can be met flexibly.

According to Fig. 4 to Fig. 8, the first planetary gears 28a are each designed as stepped planetary gears, comprising a first gear Z1 and a second gear Z2 connected to it in a rotationally fixed manner. The first gear Z1 has a larger outer diameter than the second gear Z2. The first gear Z1 meshes with the first sun gear 25a, whereby the second gear Z2 meshes with the first ring gear 27a. The first planetary gears 28a designed as stepped planets ensure the The desired large stationary gear ratio can be represented on the first planetary gear set 8 without the ring gear diameter of the first ring gear 27a of the first planetary gear set 8 becoming too large. The difference between the embodiments according to Fig. 4 and Fig. 5 is only in the axial order of the gears Z1, Z2 of the first planetary gears 28a of the first planetary gear set. According to Fig. 4, viewed from left to right, the second gear Z2 is arranged in front of the first gear Z1 on the first planet carrier 27a. In Fig. 5, this is reversed. Otherwise, the embodiments according to Fig. 4 and Fig. 5 are identical to Fig. 2.

Depending on the design and installation space situation, a cone angle of the teeth of the outer, second planetary gear 28b can be smaller than 90°, cf.

Fig. 6. This depends on the angle of the planetary axis to the drive axis or the second rotation axis 16 to the first rotation axis 15, as well as on the diameter of the planetary gears 28a, 28b.

Analogous to Fig. 3, it is also conceivable for the embodiments according to Fig. 7 and Fig. 8 to choose the angle of the second rotation axis 16 relative to the first rotation axis 15 to be greater than 90°. The axial arrangement of the gears Z1, Z2 of the first planetary gears 28a can also be designed as desired, analogous to Fig. 4 and Fig. 5. This is always done taking into account the available installation space in the vehicle 1.

A gear 3 according to Fig. 4 or Fig. 8 also has a high level of efficiency and requires little installation space. In addition, specific installation space requirements can be met flexibly.

According to Fig. 9 and Fig. 10, the connection of the gear set elements is different compared to the other embodiments. This is to make it clear that the respective connection of the gear set elements sun gear, planet carrier and ring gear can be made and adapted depending on the requirements for the gear ratios including the sign. In the present case, the first gear set element of the first planetary gear set 8 is the sun gear 25a, the second gear set element of the first planetary gear set 8 is the ring gear 27a and the third gear set element of the first planetary gear set 8 is the planet carrier 26a. The first gear set element of the second planetary gear set 9 is the ring gear 27b, the second gear set element of the second planetary gear set 9 is the planet carrier 26b and the third gear set element of the second planetary gear set 9 is the sun gear 25b. The input shaft 4 is therefore rotationally connected to the first sun gear 25a, the first ring gear 27a is rotationally connected to the first output shaft 5, and the first planet carrier 26a is connected to the second ring gear 27b via a coupling shaft 14. The second planet carrier 26b is also fixed to the stationary component 13 via the shaft 20, with the second sun gear 25b being rotationally connected to the second output shaft 6.

With the exception of the connection, the gear 3 according to Fig. 9, in particular the rotation axes 15, 16, is designed analogously to Fig. 1. With regard to the embodiment according to Fig. 9, reference is also made to the embodiments of the embodiment according to Fig. 2.

According to Fig. 10, the first planet gears 28a are each designed as stepped planet gears analogous to Fig. 4 to Fig. 8. The first gear Z1 meshes with the first sun gear 25a, whereby the second gear Z2 meshes with the first ring gear 27a. Just as with the previous embodiments, the axial order of the gears Z1, Z2 of the first planet gears 28a of the first planetary gear set 8 can be adapted depending on the space required or available installation space. According to Fig. 10, viewed from left to right, the first gear Z1 is arranged in front of the second gear Z2 on the first planet carrier 27a. With regard to the embodiment according to Fig. 10, reference is also made to the embodiments of the embodiment according to Fig. 4 to Fig. 8.

According to Fig. 11 and Fig. 12, between the first input shaft 4 and the first gear set element of the first planetary gear set 8, here the first sun gear 25a, a gear ratio 12 is arranged. The gear ratio 12 is to be understood as the pre-transmission of the transmission 3.

According to Fig. 11, the transmission stage 12 is a planetary gear with a third planetary gear set 10, comprising the gear set elements third sun gear 25c, third planet carrier 26c and third ring gear 27c. The third planetary gear set 10 is a minus planetary gear set, so that third planetary gears 28c of the third planetary gear set 10, which are rotatably mounted on the third planet carrier 26c, mesh with the third sun gear 25c and the third ring gear 27c. The third ring gear 27c is connected in a rotationally fixed manner to the input shaft 4, with the third sun gear 25c being fixed to the stationary component 13. The output of the transmission stage 12 takes place via the third planet carrier 26c, which is connected via an intermediate shaft 21 in a rotationally fixed manner to the first gear set element of the first planetary gear set 8 of the differential 7, in this case to the first sun gear 25a. The transmission stage 12 is arranged axially between the drive unit 22 according to Fig. 1 and the differential 7.

The gear ratio increases the overall gear ratio of the transmission 3. Furthermore, the respective transmission 3 according to Fig. 11 is designed in a similar way to the embodiment according to Fig. 5, so that reference is made to the corresponding description sections. It should be mentioned that, depending on the required gear ratio, the connection of the gear set elements of the third planetary gear set 10 can be exchanged as desired.

The gear ratio 12 according to Fig. 12 is a spur gear stage 24, comprising a third gear Z3 and a fourth gear Z4 meshing with it. The third gear Z3 is connected in a rotationally fixed manner to the input shaft 4 of the transmission 3. The input shaft 4 arranged on the first rotation axis 15 is, in contrast to the previous embodiments, axially parallel to the output shafts 5, 6, whereby the gear ratio 12 can compensate for an axial offset in addition to the aforementioned increase in the overall gear ratio. The drive axle is thus offset parallel to the output axle on which the output shafts 5, 6 are arranged. Such an arrangement can be advantageous if the drive unit 22 is an internal combustion engine. The fourth gear Z4 is connected in a rotationally fixed manner to the first gear set element of the first planetary gear set 8 of the differential 7 via an intermediate shaft 21. here with the first sun gear 25a. Otherwise, the respective gear 3 according to Fig. 12 is designed analogously to the embodiment according to Fig. 5, so that reference is made to the corresponding description sections.

At the point of a pure gear ratio, a multi-speed transmission 17 can be arranged between the first input shaft 4 and the first gear set element or the first sun gear 25a of the first planetary gear set 8. This is shown in another example according to Fig. 13. In this case, a 2-speed group is connected upstream of the differential gear. This is, for example, a planetary transmission with a third planetary set 10, comprising the gear set elements third sun gear 25c, third planet carrier 26c and third ring gear 27c. The third planetary gear set 10 according to Fig. 13 is a minus planetary gear set, so that third planet gears 28c of the third planetary gear set 10, which are rotatably mounted on the third planet carrier 26c, mesh with the third sun gear 25c and the third ring gear 27c. The third ring gear 27c is connected to the input shaft 4 in a rotationally fixed manner. The third sun gear 25c can be fixed to the stationary component 13 via a first frictional switching element B. The output of the transmission stage 12 takes place via the third planet carrier 26c, which is connected to the first gear set element of the first planetary gear set 8 of the differential 7 in a rotationally fixed manner via an intermediate shaft 21, in this case to the first sun gear 25a. The two gears are realized on the one hand by fixing the third sun gear 25a and on the other hand by the third ring gear 27c being able to be coupled to the third sun gear 25c in a rotationally fixed manner by means of a second frictional switching element K, so that the third planetary gear set is blocked. The multi-speed transmission 17 is arranged axially between the drive unit 22 according to Fig. 1 and the differential 7. The advantage is that high output torques and high final speeds can be achieved. The switching elements B, K can also be positive-locking switching elements.

The embodiments according to Fig. 14 and Fig. 15 are essentially analogous to the example according to Fig. 5. The difference here is that a third switching element S is arranged between the first output shaft 5 and the second output shaft 6 for torque transmission between the output shafts 5, 6. In other words, the third switching element S can create a torque-transmitting connection between the output shafts 5, 6. This connection can be designed, for example, as a form-fitting connection using claws (cf.

Fig. 15). Alternatively, the connection can be implemented frictionally via one or more friction surfaces acting in parallel, for example in the form of a multi-disk clutch (see Fig. 14). Furthermore, alternatively, the torque-transmitting connection between the output shafts 5, 6 can be implemented frictionally via one or more cone-shaped friction surface or surfaces. The latter case is not shown here. A locking function of the differential 7 can therefore be implemented by the third switching element S.

As already mentioned, the connection of the gear set elements can be chosen as desired. It is also conceivable that the differential has more than two planetary gear sets 8, 9. Such a differential gear is shown in Fig. 16, and in addition to the first and second planetary gear sets 8, 9, the differential 7 also has a fourth planetary gear set 19 with several gear set elements in the form of a fourth sun gear 25d, a fourth planet carrier 26d and a fourth ring gear 27d. The fourth planetary gear set 19 is a minus planetary gear set, so that fourth planetary gears 28d of the fourth planetary gear set 19, which are rotatably mounted on the fourth planet carrier 26d, mesh with the fourth sun gear 25d and the fourth ring gear 27d.

The first sun gear 25a of the first planetary gear set 8 is connected in a rotationally fixed manner to the input shaft 4, with the first planet carrier 26a being connected in a rotationally fixed manner to the second sun gear 25b of the second planetary gear set 9 via an intermediate shaft 21. The first ring gear 27a is connected in a rotationally fixed manner to the fourth sun gear 25d of the fourth planetary gear set 19 via the coupling shaft 14. The fourth planet carrier 26d is connected in a rotationally fixed manner to the first output shaft 5, with the fourth ring gear 27d being connected in a rotationally fixed manner to the second output shaft 6 and the second ring gear 27b. The second planet carrier 26b is connected in a rotationally fixed manner to the stationary component 13 via the shaft 20. In this embodiment, too, a first output torque can be transmitted at least indirectly to the first output shaft 5 by means of the first planetary gear set 8, wherein a support torque of the first planetary gear set 8 in the second planetary gear set 9 and the fourth planetary gear set 19 can be converted in such a way that a second output torque corresponding to the first output torque can be transmitted to the second output shaft 6.

According to Fig. 16, the respective fourth planetary gear 28d of the fourth planetary gear set 19 is arranged on the second rotation axis 16 and thus obliquely, i.e. at an angle between 0° and 90° or between 90° and 180° to the first rotation axis 15 of the input shaft 4. In the present case, the angle is between 0° and 90°.

For all planetary gear sets 8, 9, 10, 19, the respective planetary gear set 8, 9, 10, 19 can always be designed as a positive planetary gear set instead of a negative planetary gear set by swapping the connection of the planet carrier and ring gear and increasing the value of the stationary gear ratio by one. This is also possible the other way round.

All embodiments according to Fig. 2 to Fig. 10 can be supplemented with a gear ratio 12, a multi-speed transmission 17 and/or a switching element S to implement a differential lock.

In all embodiments shown here according to Fig. 2 to Fig. 16, the rotation axes 15, 16 have a common intersection point X. However, the rotation axes 15, 16 can also be skewed to one another so that they do not have a common intersection point. Reference symbols

1 vehicle

2 Drivetrain

3 Gearbox

4 Input shaft

5 First output shaft

6 Second output shaft

7 Differential

8 First planetary gear set

9 Second planetary gear set

10 Third planetary gear set

11a First axis

11b Second axis

12 gear ratio

13 Fixed component

14 Coupling shaft

15 First rotation axis of the input shaft

16 Second rotation axis of the planetary gear

17 multi-speed gearbox

18 Wheel

19 Fourth planetary gear set

20 Wave

21 Intermediate shaft

22 Drive unit

24 Spur gear stage

25a First sun gear of the first planetary gear set

25b Second sun gear of the second planetary gear set

25c Third sun gear of the third planetary gear set

25d Fourth sun gear of the fourth planetary gear set

26a First planet carrier of the first planetary gear set

26b Second planet carrier of the second planetary gear set

26c Third planet carrier of the third planetary gear set 26d Fourth planet carrier of the fourth planetary gear set

27a First ring gear of the first planetary gear set

27b Second ring gear of the second planetary gear set

27c Third ring gear of the third planetary gear set

27d Fourth ring gear of the fourth planetary gear set

28a First planetary gear of the first planetary gear set

28b Second planetary gear of the second planetary gear set

28c Third planetary gear of the third planetary gear set

28d Fourth planetary gear of the fourth planetary gear set

B First switching element

K Second switching element

S Third switching element

X Intersection of the rotation axes

Z1 First gear of the stepped planetary gear

Z2 Second gear of the stepped planetary gear

Z3 Third gear of the spur gear stage

Z4 Fourth gear of the spur gear stage

Claims

Patent claims

1. Transmission (3) for a drive train (2) of a vehicle (1), comprising an input shaft (4) which has a first axis of rotation (15), a first output shaft (5), a second output shaft (6), wherein a first planetary gear set (8) with a plurality of gear set elements and at least one second planetary gear set (9) operatively connected thereto with a plurality of gear set elements are operatively arranged between the input shaft (4) and the two output shafts (5, 6), wherein one of the planetary gear sets (8, 9) has at least one planetary gear (28b, 28d) with a second axis of rotation (16), wherein the second axis of rotation (16) of the respective planetary gear (28b, 28d) is arranged obliquely to the first axis of rotation (15) of the input shaft (4).

2. Transmission (3) according to claim 1, wherein the first planetary gear set (8) and the at least second planetary gear set (9) are assigned to a differential (7), wherein a first output torque can be transmitted to the first output shaft (5) at least indirectly by means of the first planetary gear set (8), wherein a support torque of the first planetary gear set (8) can be converted at least in the second planetary gear set (9) such that a second output torque corresponding to the first output torque can be transmitted to the second output shaft (6), wherein a first gear set element of the first planetary gear set (8) is operatively connected to the input shaft (4), wherein a second gear set element of the first planetary gear set (8) is at least indirectly connected in a rotationally fixed manner to the first output shaft (5), wherein a third gear set element of the first planetary gear set (8) is at least indirectly connected in a rotationally fixed manner to a first gear set element of the second planetary gear set (9). wherein a second gear set element of the second planetary gear set (9) is connected in a rotationally fixed manner to a stationary component (13), wherein a third gear set element of the second planetary gear set (9) is connected in a rotationally fixed manner to the second output shaft (6).

3. Transmission (3) according to claim 2, wherein the third gear set element of the first planetary gear set (8) is connected in a rotationally fixed manner to the first gear set element of the second planetary gear set (9) via a coupling shaft (14).

4. Gearbox (3) according to one of claims 1 to 3, wherein the second axis of rotation (16) has a common intersection point (X) with the first axis of rotation (15).

5. Gearbox (3) according to one of claims 1 to 3, wherein the second axis of rotation (16) is arranged skewed to the first axis of rotation (15).

6. Transmission (3) according to one of the preceding claims, wherein the first planetary gear set (8) is arranged at least partially radially within the second planetary gear set (9).

7. Transmission (3) according to one of claims 1 to 6, wherein the input shaft (4) and the output shafts (5, 6) have the same direction of rotation.

8. Transmission (3) according to one of claims 1 to 6, wherein the input shaft (4) rotates in a first direction of rotation which is opposite to a second direction of rotation of the output shafts (5, 6)

9. Transmission (3) according to one of claims 2 to 8, wherein a transmission stage (12) is arranged between the first input shaft (4) and the first gear set element of the first planetary gear set (8).

10. Transmission (3) according to one of claims 2 to 8, wherein a multi-speed transmission (17) is arranged between the first input shaft (4) and the first gear set element of the first planetary gear set (8).

11. Transmission (3) according to one of the preceding claims, wherein a switching element (S) for transmitting torque between the output shafts (5, 6) is arranged between the first output shaft (5) and the second output shaft (6).

12. Transmission (3) according to one of the preceding claims, wherein the first gear set element is a sun gear (25a, 25b) of the respective planetary gear set (8, 9), the second gear set element is a planet carrier (26a, 26b) of the respective planetary gear set (8, 9) and the third gear set element is a ring gear (27a, 27b) of the respective planetary gear set (8, 9).

13. Transmission (3) according to one of claims 1 to 11, wherein the first gear set element of the first planetary gear set (8) is a sun gear (25a), wherein the second gear set element of the first planetary gear set (8) is a ring gear (27a), and wherein the third gear set element of the first planetary gear set (8) is a planet carrier (26a), wherein the first gear set element of the second planetary gear set (9) is a ring gear (27b), wherein the second gear set element of the second planetary gear set (9) is a planet carrier (26b), and wherein the third gear set element of the second planetary gear set (9) is a sun gear (25b).

14. Transmission (3) according to one of the preceding claims, wherein the differential (7) further comprises a further planetary gear set (19) with a plurality of gear set elements.

15. Drive train (2) for a vehicle (1), comprising a transmission (3) according to one of the preceding claims and a drive unit (22) operatively connected to the transmission (3).