DE102018005947A1 - Electric drive train for a motor vehicle, in particular for a motor vehicle - Google Patents

Abstract

The invention relates to an electric drive train (10) with a first electric machine (12) designed to drive exactly one first wheel (64), which has a first stator (14) and a first rotor (16) that can be rotated about a first machine axis of rotation (18) ), with a second electric machine (26) designed to drive exactly one second wheel (66), which has a second stator (28) and a second one relative to the second stator (28) with the first machine axis of rotation (18) coinciding second machine axis of rotation (32) has a rotatable second rotor (30), with a first input spur gear stage (40), with a first planetary gear stage (56) and with a first output shaft (60), the first input spur gear stage (40), the first planetary gear stage ( 56) and the first output shaft (60) are arranged between the first electrical machine (12) and the first wheel (64), and wherein the first planetary gear stage (56) is axially offset, for u of the first electrical machine (12) is arranged.

Description

The invention relates to an electric drive train for a motor vehicle, in particular for a motor vehicle, according to the preamble of patent claim 1.

Such an electric drive train for a motor vehicle, in particular for a motor vehicle designed, for example, as a passenger car, is already the example DE 10 2009 033 531 A1 as known. The electric drive train comprises a first electric machine, which is designed or provided to drive exactly one first wheel of the motor vehicle. The first electrical machine comprises a first stator and a first rotor, which can be driven by the first stator and can therefore be rotated relative to the first stator about a first machine axis of rotation. The electric drive train also has a second electric machine which is designed or provided for driving exactly one second wheel of the motor vehicle. The second electrical machine has a second stator and a second rotor, which can be driven by the second stator and can therefore be rotated relative to the second stator about a second machine axis of rotation. The electrical machines are arranged relative to one another in such a way that the machine axes of rotation coincide. In other words, the second machine axis of rotation coincides with the first machine axis of rotation or vice versa, so that the machine axes of rotation lie on one another.

In addition, a first input spur gear stage is provided. The electric drive train further comprises a first planetary gear stage and a first output shaft, wherein the first input spur gear stage, the first planetary gear stage and the first output shaft are arranged between the first electric machine and the first wheel in relation to a torque flow running from the first electric machine to the first wheel are.

Furthermore, the DE 10 2012 220 562 A2 an electric drive for a vehicle, with an electric machine as a drive and with a two-speed gear as a planetary gear with two shifting elements and with a downstream reduction gear as an output. It is provided that the planetary gear can be coupled with the input and output in such a way that the first gear is designed as a direct gear.

It is also from the DE 10 2015 016 939 A1 a drive train device known, with at least one electric motor, at least one axle drive and a transmission arranged between the electric motor and the axle drive, which has exactly one planetary gear, a brake unit and a clutch unit. Here, the transmission is at least structurally provided for shifting two powershiftable transmission gears.

The object of the present invention is to further develop an electric drive train of the type mentioned at the outset in such a way that a particularly high power density of the electric drive train can be achieved.

This object is achieved by an electric drive train with the features of patent claim 1. Advantageous refinements with expedient developments of the invention are specified in the remaining claims.

In order to further develop an electric drive train of the type specified in the preamble of claim 1 in such a way that a particularly high power density can be realized, the invention provides that the first planetary gear stage is arranged offset to the first electrical machine. In addition, a first motor output of the electrical machine is directed towards a vehicle center. The first planetary gear stage is, for example, a first planetary gear set, which is also referred to as a first planetary gear set or first planetary gear set. The first planetary gear stage comprises, for example, a first sun gear, a first ring gear, a first planet carrier and at least a first planet gear, which meshes with the first sun gear and with the first ring gear, for example, and is rotatably mounted on the first planet carrier. The first sun gear, the first planet carrier and the first ring gear are first gear elements of the first planetary gear stage. For example, at least two of the first gear elements can in principle be rotated relative to one another about a first main axis of rotation of the first planetary gear stage, in particular if the two first gear elements which are rotatable relative to one another about the first main axis of rotation are not connected to one another in a rotationally fixed manner, that is to say are not locked together in a rotationally fixed manner. The feature that the first planetary gear stage is arranged axially offset from the first electrical machine is to be understood in particular to mean that the first machine axis of rotation and the first main axis of rotation are spaced apart from one another, that is to say they are disaxed from one another, for example the first machine axis of rotation and the first main axis of rotation being parallel to one another run.

The vehicle center is preferably to be understood as meaning a vehicle center plane which is spanned by a vehicle vertical direction and a vehicle longitudinal direction and which in Seen vehicle transverse direction is arranged substantially in the middle of the vehicle.

The first rotor can be driven by the first stator and can therefore be rotated relative to the first stator about the first machine axis of rotation. In this case, the first electrical machine can provide at least one first torque or a plurality of different first torques via the first rotor, the respective first torque being a first drive torque. The first wheel can be driven by the first electrical machine by means of the first drive torque, also referred to as drive torque. The first electrical machine provides the respective first torque on an output side. This means that the first torque on the first output side is provided or can be provided by the first electrical machine and thus by the first rotor, so that the respective first torque on the output side can be dissipated by the first electrical machine, in particular by the first rotor or is discharged. The first output side is, for example, the first engine output or the first engine output is arranged on the first output side, the first output side pointing towards the center of the vehicle. If, for example, the first machine axis of rotation extends at least substantially in the transverse direction of the vehicle in the completely manufactured state of the motor vehicle, then the first engine output points inward in the transverse direction of the vehicle and in particular points toward the electrical machine. If, for example, the first machine axis of rotation extends at least substantially in the longitudinal direction of the vehicle in the completely manufactured state of the motor vehicle, then the first engine output points in the longitudinal direction of the vehicle towards the center of the vehicle and thereby, for example, in the direction of the second electrical machine. The electric drive train can be designed to be particularly space-saving. At the same time, the electric drive train can provide particularly high powers and drive torques, so that a particularly high power density can be represented. For example, 430 kilowatts of installed power can be realized in an existing rear axle space, so that the motor vehicle can be accelerated particularly advantageously by means of the electric drive train. In particular, the electric drive train according to the invention can be implemented as an electric drive unit which, thanks to a compact gear structure and advantageous connection of the electric machine, is able to meet high performance requirements such as a maximum output torque, a maximum installed power and a high maximum vehicle speed in an existing installation space enable. In addition, functionalities such as parking lock, power shift capability, if multi-gear is provided, and independent setting of wheel torques can be represented. The wheels are vehicle wheels that are different from one another and are arranged, for example, on opposite sides in the vehicle transverse direction, so that, for example, the first wheel is a left wheel and the second wheel is a right wheel.

In an advantageous embodiment of the invention, the electric drive train has a second input spur gear stage and a second planetary gear stage. The second planetary gear stage is also referred to as a second planetary gear set, second planetary gear set or second planetary gear set. The second input spur gear stage and the second planetary gear stage are preferably arranged in relation to a torque flow between the second electrical machine and the second wheel that runs from the second electrical machine to the second wheel. It has proven to be particularly advantageous if the first electrical machine, the first input spur gear stage and the first planetary gear stage are each arranged on a mirror plane running perpendicular to the respective machine axis of rotation, in particular a central plane, mirrored to the second electrical machine, the second input spur gear stage and the second planetary gear stage are. In other words, the input spur gear stages are preferably arranged mirrored to one another in relation to the mirror plane. Likewise, the planetary gear stages are preferably arranged mirrored with respect to one another with respect to the mirror plane, wherein preferably the electrical machines are also mirrored with respect to one another with respect to the mirror plane. The mirror plane runs perpendicular to the machine axes of rotation. This enables a particularly high power density to be achieved since, on the one hand, the space required for the electric drive train can be kept to a particularly small extent. On the other hand, particularly high electrical powers and torques can be provided for driving the motor vehicle.

The second planetary gear stage preferably comprises a second sun gear, a second ring gear, a second planet carrier and at least one second planet gear, which preferably meshes with the second sun gear and with the second ring gear and is rotatably mounted on the second planet carrier. The second sun gear, the second ring gear and the second planet carrier are second gear elements of the second planetary gear stage. At least two of the second gear elements can be rotated relative to one another, for example, about a second main axis of rotation, in particular when the two second gear elements are not connected to one another in a rotationally fixed manner. It is preferably provided that the second Planetary gear stage is axially offset from the second electrical machine, so that preferably the second machine axis of rotation and the second main axis of rotation are spaced apart. The second machine axis of rotation and the second main axis of rotation preferably run parallel to one another.

It has also proven to be particularly advantageous if the planetary gear stages are arranged relative to one another in such a way that the main axes of rotation coincide, that is to say run on one another. In the context of the mutually mirrored arrangement of the planetary gear stages, it is particularly provided that the sun wheels are arranged mirrored to one another with respect to the mirror plane. Furthermore, the planet carriers are preferably arranged mirrored with respect to one another with respect to the mirror plane, wherein the ring gears are preferably also mirrored with respect to one another with respect to the mirror plane. The planet gears are also preferably arranged mirrored with respect to one another in relation to the mirror plane. As a result, the space requirement can be kept particularly low.

It has also proven to be particularly advantageous if the first gear elements and the second gear elements are designed as identical parts, so that the costs of the electric drive train can be kept to a particularly low level. In addition, it is preferably provided that the stators are arranged mirrored with respect to one another with respect to the mirror plane, wherein the rotors are preferably also mirrored with respect to one another with respect to the mirror plane. It is preferably provided that the rotors are designed as identical parts, alternatively or additionally the stators can be designed as identical parts. As a result, the costs can be kept to a particularly low level. The rotors, the stators and the gear elements are, for example, components of the electric drive train or are also referred to as components. The respective rotor has, for example, a machine output shaft, which is also referred to as a motor output shaft. The respective electrical machine can thus provide a respective torque for driving the respective wheel via the respective machine output shaft. Thus, for example, the second electrical machine can provide at least one second torque or a plurality of second torques that differ from one another via its second rotor, in particular via its second machine output shaft, the respective second torque also being referred to as the second drive torque or second drive torque. The second wheel can be driven by the second electrical machine by means of the respective second drive torque. The machine output shafts are, for example, components of the electric drive train or are also referred to as components. It is conceivable that apart from the two motor output shafts, all other components are identical parts, so that the costs can be kept particularly low. In order to be able to keep the installation space requirement of the electric drive train particularly small, it is provided, for example, that the two motor output shafts are mounted one inside the other and, in particular, rotatably on one another.

The first machine output shaft and the second machine output shaft are preferably arranged parallel to the main axis of rotation. The two machine output shafts and the main axis of rotation are preferably arranged parallel to an axis of rotation of the first wheel or to an axis of rotation of the second wheel.

In a particularly advantageous embodiment of the invention, a partition is provided in the central plane. In other words, a partition runs at least essentially in the central plane, the partition preferably being at least partially arranged between the electrical machines. In other words, for example, the first electrical machine is at least partially, in particular at least predominantly or completely, covered by the partition wall and vice versa along its axial direction towards the second electrical machine. At least some of the components are preferably rotatable relative to the partition.

It has been shown to be particularly advantageous if the electric drive train has at least one first bearing seat for the first output shaft that is fixedly connected to the partition. This means that the first inventory is fixed on the partition. It is conceivable that the first bearing receptacle and the partition are integrally formed with one another, or the partition and the first bearing receptacle are two separate components that are firmly connected to one another. The first output shaft is preferably rotatable on and at least partially supported in the first bearing receptacle.

A second output shaft assigned to the second electrical machine is preferably provided, the second input spur gear stage, the second planetary gear stage and the second output shaft preferably being arranged between the second electrical machine and the second wheel based on the torque flow running from the second electrical machine to the second wheel are.

At least one second bearing receptacle, which is firmly connected to the partition, is preferably provided for the second output shaft, wherein the previous and following remarks on the first bearing can easily be transferred to the second bearing and vice versa. Thus, for example, the second output shaft is rotatably mounted on and at least partially in the second bearing receptacle.

In a further embodiment of the invention, it is provided that the first planetary gear stage is covered at least partially, in particular at least predominantly or completely, along its radial direction outwards by the rotor of the first electrical machine or by the electrical machine. In other words, the first planetary gear stage is preferably arranged axially overlapping the first rotor of the first electrical machine, as a result of which the installation space requirement can be kept particularly small.

The second planetary gear stage is preferably at least partially covered along its radial direction to the outside by the second rotor of the second electrical machine or by the second electrical machine, so that the second planetary gear stage is preferably arranged axially overlapping the second rotor of the second electrical machine. As a result, the space requirement can be kept in a particularly small frame.

Another embodiment is characterized in that the electric drive train has a first output spur gear stage, which is at least partially covered by a first housing of the electric machine along its radial direction to the outside. In other words, the first output spur gear stage is arranged axially overlapping to one of the first housing of the first electrical machine.

It has also proven to be advantageous if the electric drive train has a second output spur gear stage which is at least partially covered along its radial direction outwards by a second housing of the second electric machine. Thus, the second output spur gear stage is preferably arranged axially overlapping the second housing of the second electrical machine. The previous and following explanations regarding the first output spur gear stage can also be easily transferred to the second output spur gear stage. Due to the fact that the first or the second output spur gear stage is at least partially, in particular at least predominantly or completely, covered along its radial direction to the outside by the first or second housing of the first or second electrical machine, the space requirement of the electric drive train can be reduced to a particularly small extent are held, in particular along the respective machine axis of rotation.

In a particularly advantageous embodiment of the invention, a first blocking switching element is provided for blocking the first planetary gear stage. The first blocking switching element can for example be switched between a first blocking state and a first released state. In particular, the first blocking switching element can be moved between at least a first blocking position and at least a first release position, in particular translationally and / or relative to the respective aforementioned housing. For example, the first blocking position corresponds to the first blocking state, the first release position corresponding to the first release state. In the first blocking state, at least or exactly two of the first gear elements are connected to one another in a rotationally fixed manner by means of the first blocking switching element, that is to say blocked to one another, so that the first gear elements connected to one another in a rotationally fixed manner cannot rotate relative to one another about the main axis of rotation, in particular not even when the first Planetary gear stage is driven, that is, when torques are introduced into the first planetary gear stage.

In the first release state, however, the first interlocking switching element releases the first gear elements, which are connected in the first interlocking state in a rotationally fixed manner by means of the first interlocking switching element, in particular for a relative rotation with respect to one another about the first main axis of rotation, so that the first gear elements which are in the first Interlocking state are rotatably connected to one another by means of the first interlocking switching element, can rotate about the main axis of rotation relative to one another or can rotate relative to one another, in particular when the first planetary gear stage is driven.

It has proven to be particularly advantageous if a second blocking shift element is provided for blocking the second planetary gear stage. For example, the second blocking switching element can be switched between a second blocking state and a second released state. In particular, the second blocking switching element can be moved between at least one second blocking position and at least one second release position, in particular translationally and / or relative to the respective, aforementioned housing. The second blocking position corresponds to the second Blocked state, the second release position corresponding to the second release state.

In the second blocking state, at least or exactly two of the second transmission elements of the second planetary gear stage are connected to one another in a rotationally fixed manner by means of the second blocking shift element, that is to say they are interlocked with one another, so that they cannot rotate relative to one another about the second main rotational axis, in particular not even when the second planetary transmission stage is driven, that is, when torques are introduced into the second planetary gear stage. In the second release state, however, the second interlocking switching element releases the second gear elements, which in the second interlocking state are non-rotatably connected to one another by means of the second interlocking switching element, in particular for rotation about the second main axis of rotation relative to one another. Thus, the second gear elements, which are non-rotatably connected to one another in the second blocking state by means of the second blocking switching element, can rotate relative to one another in the second release state, in particular about the second main axis of rotation, when the second planetary gear stage is driven.

The first or second planetary gear stage is preferably arranged axially overlapping to the first electrical machine or to the second electrical machine and thus at least partially, in particular at least predominantly or completely, covered along its radial direction to the outside by the first or second electrical machine.

It has been shown to be particularly advantageous if the electric drive train has a first braking element for braking at least one of the first transmission elements. This is to be understood in particular to mean that the at least one first gear element can be influenced, in particular slowed down or braked, with respect to its rotation relative to the respective housing by means of the first brake element, it being conceivable that the at least one gear element can be rotatably attached to the by means of the first brake element each housing can be fixed or rotatably fixed to the respective housing.

It has proven to be particularly advantageous if the electric drive train has a second braking element for braking at least one of the second transmission elements, so that, for example, the rotation of the at least one second transmission element relative to the respective housing can be impaired, in particular fixed, by means of the second braking element , As a result, a particularly advantageous shifting capability, in particular power shifting capability, of the electric drive train, in particular of a transmission of the electric drive train, can be realized in a space-saving manner. For example, a first gear assigned to the electrical machine is provided, which comprises at least the first input spur gear stage and the first planetary gear stage. The first transmission may further include the first output spur gear stage. The second electrical machine is assigned, for example, a second gear, which comprises at least the second input spur gear stage and the second planetary gear stage.

Furthermore, the second transmission can comprise the second output spur gear stage. The first transmission includes, for example, the first interlocking switching element and / or the first braking element. The second transmission includes, for example, the second interlocking switching element and / or the second braking element. In particular, at least or exactly two gears of the respective transmission can be realized, wherein the gears can be shiftable, in particular power shiftable. In other words, the respective transmission can be a two-speed transmission structure, so that the respective electrical machine can be coupled in a wheel-selective manner via the respective two-speed transmission structure. The respective gear, also referred to as the gear structure, can maximize the active length of the respective electrical machine by using only one wheel plane between the electrical machines. For shifting, in particular power shifting, of the at least or exactly two gears of the respective transmission, the respective transmission comprises, for example, a shift unit, which can preferably be placed in a space-neutral manner on a respective output of the transmission. The respective switching unit preferably comprises a switchable, in particular a power switchable, freewheel and / or a multi-plate clutch and preferably the respective planetary gear set. A first of the gears has, for example, a first gear ratio, the second gear having a second gear ratio. The translations are preferably different from one another. For example, the second translation is less than the first translation. The second gear is preferably optimized for efficiency and / or a block gear in which, for example, the respective planetary gear stage is blocked and the freewheel is open.

A variant of the respective transmission structure with only exactly one gear can be derived in a modularly simple manner from the respective two-speed transmission structure, for example by the respective switching unit through a direct connection between one also referred to as a final drive Final translation and a sideshaft is replaced. The respective wheel can be driven by the respective electrical machine via the side shaft.

In order to keep the installation space requirement particularly small, it is provided in a further embodiment of the invention that the respective braking element is arranged on a side of the respective blocking switching element facing away from the vehicle center, in particular in the axial direction of the respective planetary gear stage.

In a further embodiment of the invention, it is provided that a first output shaft part of the first output shaft of the first planetary gear stage is arranged concentrically with a hollow shaft connection part of the first brake element and within the hollow shaft connection part. As a result, the space requirement can be kept particularly low, so that a particularly high power density can be represented.

It has also been shown to be particularly advantageous if a second output shaft part of the second output shaft of the second planetary gear stage is arranged concentrically with a second hollow shaft connection part of the second brake element and within the second hollow shaft connection part. This enables particularly high power densities to be represented.

In a particularly advantageous embodiment of the invention, the first input spur gear stage is arranged downstream of the first electric machine, the first planetary gear stage downstream of the first input spur gear stage and the first wheel downstream of the first planetary gear stage, based on the torque flow running from the first electrical machine to the first wheel. In other words, it is preferably provided that the first electrical machine, the first input spur gear stage, the first planetary gear stage and the first wheel are arranged in the following order in relation to the torque flow running from the first electrical machine to the first wheel: first electrical machine - first input spur gear stage - first planetary gear stage - first wheel.

It has furthermore proven to be particularly advantageous if the second electrical machine, the second input spur gear stage, the second planetary gear stage and the second wheel are arranged in the following sequence in relation to the torque flow running from the second electrical machine to the second wheel: second electrical Machine - second input spur gear stage - second planetary gear stage - second wheel. The respective output shaft is preferably arranged between the respective planetary gear stage and the respective wheel or the respective planetary gear stage comprises the respective output shaft, so that the respective planetary gear stage provides output moments for driving the respective wheel via the respective output shaft can.

Another embodiment is characterized by a one-piece housing part, which forms both a cylindrical jacket around the first electrical machine and a first wall for receiving a first gear bearing. This allows a particularly advantageous storage to be represented in a space-saving and cost-effective manner.

Finally, it has proven to be particularly advantageous if the housing part at least partially directly delimits cooling channels through which a cooling fluid, in particular a cooling liquid, can flow for cooling the first electrical machine and / or for cooling the second electrical machine. The feature that the housing part directly delimits the cooling channels at least partially, in particular at least predominantly, means in particular that the cooling fluid flowing through the cooling channels flows directly on and around the first housing part or respective wall regions of the housing part delimiting the cooling channels and can touch directly.

Further advantages, features and details of the invention result from the following description of preferred exemplary embodiments and from the drawing. The features and combinations of features mentioned above in the description and the features and combinations of features mentioned below in the description of the figures and / or shown alone in the figures can be used not only in the combination indicated in each case, but also in other combinations or on their own, without the scope of Leaving invention.

• 1 eine schematische Darstellung eines erfindungsgemäßen elektrischen Antriebsstrangs gemäß einer ersten Ausführungsform;
• 2 eine schematische Darstellung einer ersten Bauvariante, welche auf besonders einfache und kostengünstige Weise von dem elektrischen Antriebsstrang abgeleitet werden kann; und
• 3 eine schematische Darstellung einer zweiten Bauvariante, die auf besonders einfache und kostengünstige Weise von dem elektrischen Antriebsstrang abgeleitet werden kann.

The drawing shows in:

• 1 a schematic representation of an electric drive train according to the invention according to a first embodiment;
• 2 a schematic representation of a first construction variant, which can be derived from the electric drive train in a particularly simple and inexpensive manner; and
• 3 is a schematic representation of a second construction variant, which can be derived from the electric drive train in a particularly simple and inexpensive manner.

In the figures, identical or functionally identical elements are provided with the same reference symbols.

1 shows a schematic representation of an electric drive train 10 for a motor vehicle, in particular for a motor vehicle which is preferably designed as a passenger car. In its fully manufactured state, the motor vehicle is designed as an electric vehicle and, for example, as a battery-electric vehicle (BEV). Thus, the motor vehicle is preferably only electrically driven. In particular, the motor vehicle, which in its completely manufactured state has the electric drive train 10 has, exclusively or also by the electric drive train 10 are electrically powered. The electric drive train is in the fully manufactured state of the motor vehicle 10 For example, assigned to an axle, in particular a rear axle, of the motor vehicle, so that by means of the electric drive train 10 exactly two wheels spaced apart in the vehicle transverse direction, in particular rear wheels, of the axle, in particular the rear axle, can be driven electrically.

For this purpose, the electric drive train includes 10 a first electrical machine 12 , which is designed to drive exactly a first of the wheels. Thus, by means of the electrical machine 12 based on the wheels, only the first wheel can be driven electrically. For this purpose, the electrical machine includes 12 a first stator 14 and a first rotor 16 which of the stator 14 drivable and around a first machine axis of rotation 18 relative to the rotor 14 is rotatable. In other words, the rotor 16 from the stator 14 driven and thereby around the machine axis of rotation 18 relative to the stator 14 be rotated. The rotor 16 has, for example, a first machine output shaft, also referred to as a motor output shaft 20 on which the electrical machine 12 can provide respective first torques for driving the first wheel. Thus the electrical machine 12 about the rotor 16 provide the respective first torque for driving the first wheel. During operation of the electric powertrain 10 the respective first torque via a first engine output 22 of the electrical machine 12 from the electrical machine 12 dissipated, the first engine output 22 on a first output side 24 of the electrical machine 12 is arranged.

The electric drivetrain 10 also includes a second electrical machine 26 , which is designed to drive exactly the second wheel. In other words, by means of the electrical machine 26 based on the wheels, only the second wheel can be driven electrically. For this purpose, the second electrical machine comprises 26 a second stator 28 and a second rotor 30 which of the stator 28 drivable and about a second machine axis of rotation 32 relative to the stator 28 is rotatable. The rotor can 30 from the stator 28 driven and thereby around the machine axis of rotation 32 relative to the stator 28 be rotated. The second rotor 30 has a second machine output shaft, also referred to as a second motor output shaft 34 on which the electrical machine 26 can provide respective second torques for electrically driving the second wheel. Thus the electrical machine 26 about the rotor 30 provide the respective second torque for electrically driving the second wheel. During the aforementioned operation, the respective second torque from the second electrical machine 26 via a second engine output 36 from the electrical machine 26 dissipated, the second engine output 36 on a second output side 38 of the electrical machine 26 is arranged. Thus, the electrical machines 12 and 26 the respective torque for driving the respective wheel on the respective output side 24 respectively 38 ready on which the respective torque for driving the respective wheel of the respective electrical machine 12 respectively 26 is dissipated.

Out 12 is recognizable that the electrical machines 12 and 26 are arranged relative to each other in such a way that the machine axes of rotation 18 and 32 to collapse, that is, to run together. Here are the output sides 24 and 38 in the axial direction of the respective electrical machine 12 respectively 26 facing each other.

The first electrical machine 12 is a first input spur gear stage 40 assigned which is a first gear 42 , a second gear 44 and a third gear 46 having. The gears 42 . 44 and 46 are respective spur gears, with the gear 44 is an intermediate gear. The gear 42 is from the machine output shaft 20 drivable and, for example, non-rotatable with the machine output shaft 20 connected.

The second electrical machine 26 is a second input spur gear stage 48 assigned which is a fourth gear 50 , a fifth gear 52 and a sixth gear 54 having. The gear 52 is, for example, an intermediate gear. The gear 50 is from the machine output shaft 34 drivable and, for example, non-rotatable with the machine output shaft 34 connected. The gear 44 meshes with the gears at the same time 42 and 46 , the gear 52 simultaneously with the gears 50 and 54 combs. So the gear 46 about the gear 44 from the gear 42 drivable, and the gear 54 and the gear 52 from the gear 50 drivable.

Furthermore, the first is electrical machine 12 a first planetary gear stage 56 assigned, the second electrical machine 26 a second planetary gear stage 58 assigned. In addition, the electrical machine 12 a first output shaft 60 assigned via which the electric drive train 10 can provide respective torques for driving the first wheel. The electrical machine 26 is a second output shaft 62 assigned via which the drive train 10 can provide respective torques for electrically driving the second wheel. Relating to one of the first electrical machines 12 The first input spur gear stage is the first torque flow running towards the first wheel 40 , the first planetary gear stage 56 and the first output shaft 60 between the first electrical machine 12 and arranged the first wheel, which in 1 is shown particularly schematically and is designated by 64. Relative to one of the second electrical machine 26 The second input spur gear stage is the second torque flow running to the second wheel 48 , the second planetary gear stage 58 and the second output shaft 62 between the second electrical machine 26 and the second wheel arranged in 1 is shown particularly schematically and is designated by 66. Further is by an arrow 68 in 1 illustrates the forward direction of travel of the motor vehicle. The machine axes of rotation run in a fully manufactured state 18 and 32 at least essentially in the vehicle transverse direction.

The first planetary gear stage is now to be able to achieve a particularly high power density 56 offset to the first electrical machine 12 arranged, and the second planetary gear stage 58 is offset to the second electrical machine 26 arranged. In addition, the first engine output 22 or the first output side 24 to a vehicle center 70 directed, with the second engine output 36 and thus the second output side 38 to the center of the vehicle 70 is directed towards. 1 shows a first embodiment of the electric drive train 10 , In the first embodiment, the engine output 22 and thus the output shaft 24 in the transverse direction of the vehicle so that the engine output 36 and thus the output side 38 Point inwards in the transverse direction of the vehicle.

The wheels 64 and 66 are rotatable about respective wheel axes of rotation relative to, for example, a body of the motor vehicle designed as a self-supporting body, the structure of which limits the interior of the motor vehicle. The wheel rotation axes preferably run in the vehicle transverse direction. The wheel axes of rotation are preferably of the machine axes of rotation 18 and 32 spaced, the wheel axes of rotation parallel to the machine axes of rotation 18 and 32 run.

The respective planetary gear stage 56 respectively 58 includes a respective sun gear 72 respectively 74 , a respective ring gear 76 respectively 78 and a respective planet carrier 80 respectively 82 , The respective planetary gear stage also includes 56 respectively 58 at least one planet gear 84 respectively 86 , which is rotatable on the respective planet carrier 80 respectively 82 is stored. The planet gear 84 meshes with the sun gear at the same time 72 and with the ring gear 76 , As a result, the planet gear meshes 86 simultaneously with the sun gear 74 and with the ring gear 78 , The sun gear 72 , the ring gear 76 and the planet carrier 80 are the first gear elements of the planetary gear stage 56 , The sun gear 74 , the ring gear 78 and the planet carrier 82 are second gear elements of the planetary gear stage 58 , If, for example, the first gear elements are not connected to one another in a rotationally fixed manner, the first gear elements can basically rotate about a main axis of rotation 88 the first planetary gear stage 56 rotate relative to each other, especially when the planetary gear stage 56 is driven. As a result, the second gear elements can rotate about a second main axis of rotation 90 the planetary gear stage 58 rotate relative to one another if the second gear elements are not connected to one another in a rotationally fixed manner or would be connected to one another. The main axes of rotation preferably fall 88 and 90 together. With the feature that the respective planetary gear stage, also referred to as a planetary gear set or planetary gear set 56 respectively 58 offset to the respective electrical machine 12 respectively 26 is arranged, it is to be understood in particular that the respective main axis of rotation 88 respectively 90 from the respective machine axis of rotation 18 respectively 32 is spaced. The respective main axis of rotation preferably runs 88 respectively 90 parallel to the respective machine axis of rotation 18 respectively 32 ,

Out 1 it can be seen that the respective planet carrier 80 respectively 82 non-rotatable with the respective output shaft 60 respectively 62 connected is.

Furthermore is out 1 particularly recognizable that the first electrical machine 12 , the first input spur gear stage 40 and the first planetary gear stage 56 each on a perpendicular to the respective machine axis of rotation 18 respectively 32 extending and in particular designed as a central plane mirror plane 92 mirrored to the second electrical machine 26 , the second input spur gear stage 48 and the second planetary gear stage 58 are arranged. It runs at least essentially in the middle plane (mirror plane 92 ) a partition 94 which along the respective machine axis of rotation 18 respectively 32 between the electrical machines 12 and 26 is arranged. Here is the electrical machine 12 along their axial direction to the electrical machine 26 down at least partially, in particular at least predominantly or completely, through the partition 94 covered. As a result, the electrical machine 26 along their axial direction to the electrical machine 12 down at least partially, in particular at least predominantly or completely, through the partition 94 covered.

The electric drivetrain 10 has at least one with the partition 94 firmly connected first assessment 96 for the first output shaft 60 on. In addition, the electric drive train has 10 at least one with the partition 94 firmly connected second inventory 98 for the second output shaft 62 on. The output shafts 60 and 62 are in the warehouse 96 and 98 rotatably mounted and therefore rotatable on the partition 94 stored. The camp recordings 96 and 98 are therefore also referred to as output bearing mounts. For example, in the inventory 96 and 98 respective bearing elements, in particular roller bearings, arranged, via which the output shafts 60 and 62 rotatable on the partition 94 are stored. The output shafts 60 and 62 are about the main axes of rotation 88 and 90 relative to the partition 94 rotatable.

The partition 94 is, for example, part of a housing 100 of the drive train 10 , for example in the housing 100 the electrical machines 12 and 26 , the input spur gears 40 and 48 and the planetary gear stages 56 and 58 are included. The gear elements are particularly when they are not rotationally fixed to the housing 100 are connected, relative to the housing 100 rotatable. In particular, the rotors 16 and 30 and the machine axes of rotation 18 and 32 relative to the housing 100 rotatable.

The first planetary gear stage 56 is at least partially, in particular at least predominantly or completely, through the first electrical machine along its radial direction to the outside 12 and in particular through the first rotor 16 covered. The second planetary gear stage is correspondingly 58 along its radial direction outwards at least partially, in particular at least predominantly or completely, by the second electrical machine 26 and through the second rotor 30 covered.

The first electrical machine 12 is a first output spur gear stage 102 assigned, the second electrical machine 26 a second output spur gear 104 assigned. The output spur gear stages 102 and 104 are related to the mirror plane 92 arranged mirrored to each other. The output spur gear stage 102 has a seventh gear 106 and an eighth gear 108 on which with the gear 106 combs. The gear 106 is coaxial with the gear 46 arranged and from the gear 46 drivable. The gears 106 and 108 are, for example, respective spur gears.

The output spur gear stage 104 has a ninth gear 110 and a tenth gear 112 on which with the gear 110 combs. The gear 110 is coaxial with the gear 54 arranged and from the gear 54 drivable. The gear 108 is from the gear 106 drivable, and the gear 112 is from the gear 110 drivable. For example, the gears 46 and 106 with a common wave 114 non-rotatably connected. For example, the gears 54 and 110 together through a wave 116 non-rotatably connected. The gears 110 and 112 are respective spur gears.

Out 1 it can be seen that, for example, the gear 108 rotatable with the ring gear 76 connected is. Furthermore, the gear 112 rotatable with the ring gear 78 connected. The respective ring gear 76 respectively 78 is thus a respective input via which the respective one of the respective electrical machine 12 respectively 26 provided torque in the respective planetary gear stage 56 respectively 58 can be initiated.

The output spur gear stage 102 is along its radial direction outwards at least partially, in particular at least predominantly or completely, through a first housing part 118 of the electrical machine 12 covered. The housing part 118 is part of the housing, for example 100 , The housing part 118 and the partition 94 can be formed in one piece with one another or can be components formed separately from one another. The output spur gear stage 104 is at least partially, in particular at least predominantly or completely, along its radial direction outwards by an in 1 not shown second housing of the second electrical machine 26 covered. The second housing of the second electrical machine 26 can be part of the housing 100 his. The second housing of the second electrical machine 26 can be made in one piece with the partition 94 be formed, or the second housing of the second electrical machine 26 and the partition 94 are separate components. The first housing part 118 the first electrical machine 12 is also referred to as the first housing element, for example. The second housing of the second electrical machine 26 becomes for example, also referred to as a second housing part or second housing element. The housing parts can be formed in one piece with one another, or the housing parts are separately formed and, for example, at least indirectly, in particular directly, connected components.

The first planetary gear stage 56 is a first interlock switching element 120 assigned, by means of which at least or exactly two of the first gear elements can be connected to one another in a rotationally fixed manner and thereby blocked together. In these, by means of the blocking switching element 120 Gear elements of the planetary gear stage which can be connected in a rotationally fixed manner 56 in the present case it is the sun gear 72 and the ring gear 76 which by means of the blocking switching element 120 can be rotatably connected to each other.

The second planetary gear stage 58 is a second interlock switching element 122 assigned by means of which at least or exactly two of the second gear elements can be connected to one another in a rotationally fixed manner. Are present by means of the second blocking switching element 122 the second sun gear 74 and the second ring gear 78 non-rotatably connectable.

It is also the first planetary gear stage 56 a first braking element 124 assigned by means of which at least one of the first gear elements can be braked, in particular relative to the respective housing part. The second planetary gear stage 58 is a second braking element 126 assigned by means of which at least or exactly one of the second gear elements, in particular relative to the respective housing part, can be braked. In the first embodiment, the respective braking element 124 respectively 126 designed as a freewheel, in particular as a switchable freewheel and preferably as a power switchable freewheel. By means of the respective freewheel, the respective gear element can be in at least or exactly one about the respective main axis of rotation 88 respectively 90 running direction of rotation relative to the respective housing part, fixed, that is rotatably connected to the respective housing part. In the present case, the respective sun gear 72 respectively 74 by means of the respective braking element 124 respectively 126 be braked.

In order to create a particularly space-saving arrangement, it is provided that the respective braking element 124 respectively 126 on a respective, the vehicle center 70 side facing away in the axial direction of the respective planetary gear set 128 respectively 130 of the respective blocking switching element 120 respectively 122 is arranged. Furthermore, a respective output shaft part of the respective output shaft is, for example 60 respectively 62 concentric to a respective hollow shaft connecting part of the respective braking element 124 respectively 126 and arranged within the respective hollow shaft connecting part.

The electrical machine is related to the first torque flow 12 , the input spur gear 40 , the output spur gear 102 , the planetary gear stage 56 and the wheel 64 arranged in the following order: electrical machine 12 - input spur gear 40 - Output spur gear stage 102 - planetary gear stage 56 - wheel 64 , The electrical machine is related to the second torque flow 26 , the input spur gear 48 , the output spur gear 104 and the planetary gear stage 58 as well as the wheel 66 arranged in the following order: electrical machine 26 - input spur gear 48 - Output spur gear stage 104 - planetary gear stage 58 - bike 66.

In the first embodiment, for example, the first housing part 118 a one-piece housing part, which both a cylindrical jacket 132 the first electric machine 12 a first wall as well 134 forms for receiving a first gear bearing. The second housing part is preferably a one-piece second housing part, which has a second cylindrical jacket around the second electrical machine 26 and forms a second wall for receiving a second gear bearing. Out 1 is recognizable that the gear 106 and / or the gear 46 by means of the wall 134 rotatable on the housing part 118 are stored. For example, in the wall 134 an in 1 Unrecognizable bearing part, in particular a roller bearing, added, via which the gear 46 respectively 106 rotatable on the housing part 118 is stored. In particular, the wave 114 at least partially in the wall 134 arranged and rotatable on the bearing part on the housing part 118 stored. These comments on the gears 46 and 106 , to the wave 114 , to the first housing part 118 and to the first wall 134 can also easily on the gears 54 and 110 , on the wave 116 , on the second housing part of the electrical machine 26 and transferred to the second recording and vice versa.

Furthermore, it is preferably provided that the respective housing part at least partially directly limits cooling channels, which are provided by a cooling fluid for cooling the respective electrical machine 12 respectively 26 are flowable. The respective housing part at least partially directly limits the cooling channels, so that the cooling fluid, for example in the form of a cooling liquid and flowing through the cooling channels, flows through the respective housing part or flow directly to and around respective wall areas of the respective housing part and thus can directly touch them.

Also with the partition 94 Recordings 140 and 142 firmly connected, the recordings 140 and 142 for example in one piece with the partition 94 are formed or by the partition 94 are formed. The respective wave 114 respectively 116 is in the respective recording 140 respectively 142 rotatable on the partition 94 stored so that the respective gear 46 respectively 106 respectively 54 respectively 110 in the respective recording 140 and 142 on the partition 94 is rotatably mounted. It is, for example, in the respective recording 140 respectively 142 a bearing element, in particular a roller bearing, added, via which the respective gear 106 . 46 . 54 . 110 or the respective wave 114 respectively 116 rotatable on the partition 94 is stored.

The aforementioned idler gear (gear 44 respectively 52 ) only has the task of ensuring a sufficient center distance between the respective machine axis 18 respectively 32 and the respective main axis of rotation 88 respectively 90 to be able to implement, in particular in such a way that the respective planetary gear set parallel in addition to the respective electrical machine 12 respectively 26 can be placed.

Furthermore, a parking lock can be implemented in a particularly advantageous manner. The parking lock includes a parking lock wheel 136 which rotates with the shaft 114 connected is. So the parking lock wheel 136 about the planetary gear stage 56 especially permanent torque transmission with the wheel 64 coupled so that when the wave 114 relative to the housing 100 can turn the shaft 114 always by bike 64 with turns when the wheel 64 is rotated relative to the structure.

The parking lock includes, for example, an in 1 not recognizable locking element, by means of which the parking lock wheel 136 and thus the wave 114 rotatably on the housing 100 can be set. This will make the wheel 64 secured against rotation relative to the body, so that, for example, when the motor vehicle is parked or parked on a slope, without any desired rotation of the wheel 64 and thus an undesired rolling away of the motor vehicle can be avoided.

Since in the first embodiment, the electrical machines 12 and 26 so-called torque vectoring functionality can be implemented, in the context of which the respective torque, by means of which the respective wheel 64 respectively 66 is driven, at least essentially independently of the respective other torque by means of which the wheel 66 respectively 64 is driven, can be adjusted.

2 shows a first construction variant, which in a particularly simple and inexpensive manner from the electric drive train 10 can be derived according to the first embodiment. While at the in 1 shown first embodiment, the two electrical machines 12 and 26 and ever electrical machine 12 and 26 at least or exactly two shiftable, in particular power shiftable, gears are provided in the in 2 shown first construction variant exactly one electrical machine 12 and at least or exactly two shiftable, in particular power shiftable, gears are provided. Here are the wheels 64 and 66 from the electrical machine 12 via a differential gear 138 drivable, which is designed for example as an open differential or as a limited slip differential.

Finally shows 3 a second construction variant, which is also particularly simple and inexpensive from the in 1 shown first embodiment can be derived. In the second construction variant, there are exactly two electrical machines 12 and 26 and at least or exactly one gear is provided, since, for example, simply the planetary gear stages 56 and 58 omitted. Here is the gear 108 respectively 112 rotationally fixed to the respective output shaft 60 respectively 62 arranged and, for example, non-rotatably with the respective output shaft 60 respectively 62 connected.

LIST OF REFERENCE NUMBERS

10

electric drivetrain

12

electrical machine

14

stator

16

rotor

18

Engine rotational axis

20

Engine output shaft

22

engine output

24

output side

26

electrical machine

28

stator

30

rotor

32

Engine rotational axis

34

Engine output shaft

36

engine output

38

output side

40

Eingangsstirnradstufe

42

gear

44

gear

46

gear

48

Eingangsstirnradstufe

50

gear

52

gear

54

gear

56

Planetary gear stage

58

Planetary gear stage

60

output shaft

62

output shaft

64

wheel

66

wheel

68

arrow

70

vehicle center

72

sun

74

sun

76

ring gear

78

ring gear

80

planet carrier

82

planet carrier

84

planet

86

planet

88

Main axis of rotation

90

Main axis of rotation

92

mirror plane

94

partition wall

96

bearing seat

98

bearing seat

100

casing

102

Ausgangsstirnradstufe

104

Ausgangsstirnradstufe

106

gear

108

gear

110

gear

112

gear

114

wave

116

wave

118

housing part

120

Verblockungsschaltelement

122

Verblockungsschaltelement

124

braking element

126

braking element

128

page

130

page

132

coat

134

wall

136

parking gear

138

differential gear

140

admission

142

admission

QUOTES INCLUDE IN THE DESCRIPTION

This list of documents listed by the applicant has been generated automatically and is only included for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• DE 102009033531 A1 [0002]
• DE 102012220562 A2 [0004]
• DE 102015016939 A1 [0005]

Claims (13)

Electrical drive train (10) for a motor vehicle, with a first electrical machine (12) designed to drive exactly one first wheel (64) of the motor vehicle, which has a first stator (14) and one that can be driven by the first stator (14) and relative to it the first stator (14) has a first rotor (16) rotatable about a first machine axis of rotation (18), with a second electrical machine (26) which is designed to drive exactly one second wheel (66) of the motor vehicle and which has a second stator (28) and has a second rotor (30) which can be driven by the second stator (28) and rotates relative to the second stator (28) about a second, second machine rotation axis (32) coinciding with the first machine rotation axis (18), with a first input spur gear stage (40) , With a first planetary gear stage (56) and with a first output shaft (60), the first input spur gear stage (40), the first planetary gear stage (56) and the first output shaft (60) in relation to a torque flow running from the first electrical machine (12) to the first wheel (64) between the first electrical machine (12) and the first wheel (64), characterized in that the first planetary gear stage (56 ) is arranged axially offset from the first electrical machine (12), a first motor output (22) of the first electrical machine (12) being directed towards a vehicle center (70). Electric drive train (10) after Claim 1 , characterized by a second input spur gear stage (48) and a second planetary gear stage (58) which relate to a torque flow between the second electric machine (26) and the second gear running from the second electric machine (26) to the second wheel (66) (66) are arranged, the first electrical machine (12), the first input spur gear stage (40) and the first planetary gear stage (56) each mirrored to the second electrical one at a mirror plane (92) running perpendicular to the respective machine axis of rotation (18, 32) Machine (26), the second input spur gear stage (48) and the second planetary gear stage (58) are arranged. Electric drive train (10) after Claim 2 , characterized by a partition (94) arranged in the mirror plane (92). Electric drive train (10) after Claim 3 , characterized by at least one first bearing receptacle (96) for the first output shaft (60) which is fixedly connected to the partition (94). Electrical drive train (10) according to one of the preceding claims, characterized in that the first planetary gear stage (56) is at least partially covered along its radial direction outwards by the first rotor (16) of the first electrical machine (12). Electric drive train (10) according to one of the preceding claims, characterized by a first output spur gear stage (102) which is at least partially covered along its radial direction to the outside by a first housing (118) of the first electrical machine (12). Electrical drive train (10) according to one of the preceding claims, characterized by a first interlocking switching element (120) for interlocking the first planetary gear stage (56). Electric drive train (10) according to one of the preceding claims, characterized by a braking element (124) for braking at least one of first transmission elements of the first planetary gear stage (56). Electric drive train (10) according to the Claims 7 and 8th , characterized in that the braking element (124) is arranged on a side (128) of the blocking switching element (120) facing away from the vehicle center (70). Electric drive train (10) after Claim 8 or 9 , characterized in that a first output shaft part of the first output shaft (60) of the first planetary gear stage (56) is arranged concentrically with a hollow shaft connecting part of the braking element (124) and inside the hollow shaft connecting part. Electrical drive train (10) according to one of the preceding claims, characterized in that, based on the torque flow running from the first electrical machine (12) to the first wheel (64), the first input spur gear stage (40) downstream of the first electrical machine (12) , the first planetary gear stage (56) downstream of the first input spur gear stage (40) and the first gear (64) downstream of the first planetary gear stage (56). Electrical drive train (10) according to one of the preceding claims, characterized by a one-piece housing part (118) which forms both a cylindrical casing (132) around the first electrical machine (12) and a first wall (134) for receiving a first gear bearing , Electric drive train (10) after Claim 12 , characterized in that the housing part (118) of a cooling fluid for cooling the first Electrical machine (12) flow-through cooling channels at least partially directly limited.

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