Electric drive system for a motor vehicle, in particular for a car, and motor vehicle, in particular car

Abstract

Electric drive system (10) for a motor vehicle, comprising a first electric machine (12) with a first rotor (14), a second electric machine (20) with a second rotor (22), and a planetary coupling gear (30), wherein: - the coupling gear (30) comprises a first planet gear set (40) with a first ring gear (42), a first planet carrier (44) and a first sun gear (46) and a second planet gear set (50) with a second ring gear (52), a second planet carrier (54) and a second sun gear (56); - the first planet carrier (44) is connected to the second planet carrier (54) in a rotationally fixed manner; - a first output shaft (68) of the coupling gear (30) is provided, which is non-rotatably connected to the first ring gear (42), and whose first output shaft (68) is designed to transmit torques from the coupling gear (30) by bypassing the planet carriers (44, 54) and the sun gears (46, 56); - a second output shaft (70) of the coupling gear (30) is provided, which is non-rotatably connected to the second ring gear (52), and whose second output shaft (70) is designed to transmit torques from the coupling gear (30) by bypassing the planet carriers (44, 54) and the sun gears (46, 56); characterized by the fact that - with respect to an axial direction coinciding with a machine rotation axis (18, 26), the first electric machine (12) is arranged on a side (S1) of the coupling gear (30) facing away from the second electric machine (20); - a connecting shaft (67) is provided, which is designed to connect the first planet carrier (44) rotationally fixedly to a first coupling half (K1) of a parking lock (72); and - a connection point (AS) for the rotationally fixed connection of the connecting shaft (67) to the first planet carrier (44) with respect to the axial direction is arranged between the first planet gear set (40) and the second planet gear set (50).

Description

[0001] The invention relates to an electric drive system for a motor vehicle, in particular for a car, according to the preamble of claim 1. Furthermore, the invention relates to a motor vehicle, in particular a car, with at least one such electric drive system.

[0002] DE 10 2009 031 645 A1 discloses a drive unit for an electric vehicle, comprising a first electric motor for driving at least one wheel of the electric vehicle.

[0003] The generic US 9,494,218 B2 discloses an electric drive system for a motor vehicle in which two electric machines are coupled to each other via a linkage transmission, the linkage transmission having two planetary gear sets whose planet carriers are rotationally fixed to each other.

[0004] The object of the present invention is to create an electric drive system for a motor vehicle in such a way that a parking lock can be implemented in a particularly simple manner.

[0005] The problem is solved by an electric drive system with the features of claim 1. Advantageous embodiments with expedient further developments of the invention are specified in the remaining claims.

[0006] A first aspect of the invention relates to an electric drive system, also referred to as an electric drive device or designed as an electric drive device, for a motor vehicle, also referred to simply as a vehicle, in particular for a motor car and especially for a passenger car. This means that the motor vehicle, also referred to simply as a vehicle, in its fully manufactured state, has the electric drive system and can be driven by means of the electric drive system, in particular purely electrically. For example, the motor vehicle, in its fully manufactured state, has at least or exactly two axles, also referred to as vehicle axles, arranged consecutively and thus one behind the other in the longitudinal direction of the vehicle.Each axle of the motor vehicle has at least or exactly two wheels, also referred to as vehicle wheels, wherein, for example, the vehicle wheels of each axle are arranged on opposite sides of the vehicle in the transverse direction of the vehicle. By means of the electric drive system, the vehicle wheels of at least or exactly one or both axles can then be driven, in particular purely electrically, thereby enabling the entire motor vehicle to be driven. The vehicle wheels that can be driven by means of the electric drive system are also referred to as driven wheels, driven wheels, or drive wheels. When the vehicle wheels or wheels are mentioned below, unless otherwise specified, this refers to the vehicle wheels that can be driven by means of the electric drive system, i.e., the drive wheels.In particular, the vehicle wheels of the vehicle axles are ground contact elements by which the vehicle is supported or can be supported downwards against the ground in the vertical direction. If the vehicle is driven along the ground while it is supported downwards in the vertical direction by the ground contact elements of the vehicle axles, the vehicle wheels of the vehicle axles roll along the ground, especially directly.

[0007] The electric drive system comprises a first electric machine, which has a first rotor. For example, the first electric machine has a first stator, by means of which the first rotor can be driven and thus rotated about a first machine axis of rotation relative to the first stator. In particular, the first electric machine can provide first drive torques via the first rotor to drive the vehicle wheels and thus the vehicle. The electric drive system also comprises a second electric machine with a second rotor. In particular, the second electric machine has a second stator, by means of which the second rotor can be driven and thus rotated about a second machine axis of rotation relative to the second stator.In particular, the second electric machine can provide second drive torques via its second rotor, which can be used to drive the vehicle wheels and thus the vehicle itself. For example, the machine axes of rotation run parallel to each other. Specifically, the machine axes of rotation coincide, so that the electric machines are, for example, arranged coaxially.

[0008] The electric drive system also features a planetary gear set. This gear set comprises a first planetary gear set, consisting of a first ring gear, a first planet carrier (also referred to as the first carrier), and a first sun gear. The gear set also includes a second planetary gear set, consisting of a second ring gear, a second planet carrier (also referred to as the second carrier), and a second sun gear. The first ring gear, the first planet carrier, and the first sun gear are components of the first planetary gear set. The second ring gear, the second planet carrier, and the second sun gear are components of the second planetary gear set.The electric drive system, for example, has a housing in which the coupling gear can be at least partially arranged. Particularly when the respective gear element is not fixedly connected to the housing, it is rotatable about a first planetary gear set axis of rotation relative to the housing. Similarly, particularly when the respective planetary gear set element is not fixedly connected to the housing, it is rotatable about a second planetary gear set axis of rotation relative to the housing. It is particularly intended that the planetary gear set axes of rotation run parallel to each other, or, more preferably, that the planetary gear set axes of rotation coincide, so that the planetary gear sets are preferably arranged coaxially. For example, the respective machine axis of rotation runs parallel to the respective planetary gear set axis of rotation.In particular, it is provided that the respective machine axis of rotation coincides with the respective planetary gear set axis of rotation, so that it is preferably provided that the respective planetary gear set is arranged coaxially to the respective electric machine.

[0009] The first planet carrier is permanently, and therefore rotationally fixed, connected to the second planet carrier, i.e., coupled.

[0010] Within the scope of the present disclosure, the feature that two components, such as the first planet carrier and the second planet carrier, are rotationally fixed to one another is understood to mean that the components, being rotationally fixed to one another, are arranged coaxially and, in particular when the components are driven, rotate together or simultaneously and especially at the same angular velocity about a component axis of rotation common to the components, such as the first planetary gear set axis of rotation or the second planetary gear set axis of rotation, particularly relative to the housing. The feature that two components are torque-transmitting to one another is understood to mean that the components are coupled or connected to one another in such a way that torques can be transmitted between the components, wherein, when the components are rotationally fixed to one another,The components are also connected to each other in a torque-transmitting manner. The characteristic that two components are permanently connected to each other in a torque-transmitting manner means that there is no switching element that can be switched between a coupling state connecting the components in a torque-transmitting manner and a decoupling state in which no torque can be transmitted between the components via the switching element. Rather, the components are always and therefore permanently torque-transmitting, meaning they are connected to each other in such a way that torque can be transmitted between them. Thus, for example, one of the components can be driven by the other component and vice versa. In particular, the characteristic that two components, such as the first planet carrier and the second planet carrier, are permanently rotationally fixed to each other means that...that no switching element is provided which can be switched between a coupling state that connects the components in a rotationally fixed manner and a decoupling state in which the components are decoupled from each other and rotatable relative to each other, in particular about the component's axis of rotation, so that no torques can be transmitted between the components via the switching element, but rather the components are always, or rather always, permanently connected or coupled to each other in a rotationally fixed manner. In other words, the term "rotationally fixed" means that two elements are rotationally fixed to each other if they are arranged coaxially and connected in such a way that they rotate at the same angular velocity, in particular about the component's axis of rotation.

[0011] In particular, the electric drive system is a so-called electric dual drive, since each wheel of the vehicle axle comprising the electric drive system is provided with an electric machine of the electric drive system, in particular with the proviso that the vehicle axle comprising the electric drive system has exactly two vehicle wheels designed as ground contact elements (wheels).

[0012] To achieve particularly advantageous drivability, a first switching element can be provided, which is designed to connect the first rotor to the second planet carrier in a rotationally fixed manner, and in particular to the first planet carrier via the second planet carrier. In other words, the first switching element allows the first rotor to be connected to the second planet carrier in a rotationally fixed manner. For example, the first switching element can be switched between a first coupling state and a first decoupling state. In the first coupling state, the first rotor is connected to the first planet carrier in a rotationally fixed manner by means of the first switching element.In the first decoupling state, the first switching element allows relative rotations between the first rotor and the second planet carrier about the first machine axis of rotation or about the second planetary gear set axis of rotation, so that no torques can be transmitted between the first rotor and the second planet carrier via the first switching element in the first decoupling state. For example, the first switching element has a first switching part which can be moved, in particular translationally and / or relative to the housing, between at least one first coupling position that effects the first coupling state and at least one first decoupling position that effects the first decoupling state.

[0013] In a manner known per se, the coupling mechanism, and thus the electric drive system, is provided with a first output shaft, in addition to the connecting shaft, which is permanently and rotationally fixed to the first ring gear. The first output shaft is designed to transmit torques from the coupling mechanism, bypassing the planet carriers and the sun gears, also referred to as first torques or first output torques. This means that the first torques can be transmitted from the coupling mechanism via the first output shaft, bypassing the planet carriers and the sun gears. In other words, the coupling mechanism can provide the first torques, bypassing the planet carriers and the sun gears.This means that, with respect to a first torque flow via which the coupling gear provides or can provide the first torques, such that the first torques flow or flow along the first torque flow, the planet carriers and the sun gears are not arranged in the first torque flow downstream of the first output shaft.

[0014] Furthermore, the coupling mechanism, and thus the electric drive system, has a second output shaft, provided in addition to the first output shaft and the connecting shaft, which is permanently and rotationally fixed to the second ring gear. The second output shaft is designed to transmit torques from the coupling mechanism, bypassing the planet carriers and the sun gears, also referred to as second torques or second output torques. In other words, the second torques can be transmitted from the coupling mechanism via the second output shaft, bypassing the sun gears and the planet carriers. Put another way, the coupling mechanism can provide the second torques via the second output shaft, bypassing the planet carriers and the sun gears.This means that, with respect to a second torque flow along which the second torques are or can be routed out of the coupling gear via the second output shaft, the planet carriers and the sun gears are not arranged in the second torque flow downstream of the second output shaft.

[0015] To implement the parking lock in a particularly advantageous manner, saving weight, cost, and installation space, and in particular to integrate it into the electric drive system, the invention provides that, with respect to the axial direction of the electric drive system, the first electric machine is arranged on the first side of the coupling gear facing away from the second electric machine in the axial direction of the electric drive system. Preferably, with respect to the axial direction of the electric drive system, the second electric machine is arranged on the second side of the coupling gear facing away from the first electric machine in the axial direction of the electric drive system. Preferably, the axial direction of the electric drive system coincides with the respective machine axis of rotation and / or with the respective planetary gear set axis of rotation.With regard to the axial direction of the electric drive system, the first electric machine is preferably arranged on the first side of the coupling mechanism facing away from the second electric machine, such that the first electric machine is at least partially overlapped by the coupling mechanism in a first direction that runs parallel to or coincides with the axial direction of the drive system, from the first electric machine to the second electric machine. When the axial direction is mentioned before and below, unless otherwise specified, this refers to the axial direction of the electric drive system. In this respect, the term "axial" refers to the axial direction of the electric drive system unless otherwise specified.In other words, unless otherwise specified, the term "axial" refers to the axial direction of the electric machine. Accordingly, with respect to the axial direction, the second electric machine is preferably arranged on the second side of the coupling mechanism, facing away from the first electric machine, such that the second electric machine is at least partially overlapped by the coupling mechanism in a second direction that runs parallel to or coincides with the axial direction, opposite to the first direction, and extending from the second electric machine towards the first electric machine.

[0016] According to the invention, the electric drive system also includes a connecting shaft configured to connect the first planet carrier in a rotationally fixed manner to a first coupling half of a parking lock of the drive system. In other words, the electric drive system includes the parking lock, which has the first coupling half and preferably also a second coupling half. The first coupling half is also referred to as the first parking lock coupling half, and the second coupling half is also referred to as the second parking lock coupling half. For example, the first parking lock coupling half can be connected to the connecting shaft in a rotationally fixed manner and thus connected to the first planet carrier via the connecting shaft in a rotationally fixed manner. For example, the first coupling half is, in particular, permanently connected to the connecting shaft in a rotationally fixed manner.For example, the connecting shaft can be non-rotatably connected to the first planet carrier, or the connecting shaft is, in particular, permanently non-rotatably connected to the first planet carrier. More specifically, the connecting shaft is rotatable about a connecting shaft axis of rotation relative to the housing. For example, the connecting shaft runs parallel to the respective machine axis of rotation and / or the respective planetary gear set axis of rotation. Most preferably, the connecting shaft coincides with the respective machine axis of rotation and the respective planetary gear set axis of rotation. The parking lock is also referred to as the parking lock device. The parking lock coupling halves (coupling halves of the parking lock) can be non-rotatably connected to each other, whereby the connecting shaft, and via the connecting shaft the first planet carrier, and via this the second planet carrier, can be fixed non-rotatably to the housing, and thus non-rotatably connected to the housing.For this purpose, the parking lock, for example, comprises a parking lock element, also referred to as a parking lock switching element, which can be moved, for example, particularly relative to the housing and / or translationally and / or rotationally, between at least one parking lock coupling position that effects a parking lock coupling state and at least one decoupling position that effects a parking lock decoupling state. In the parking lock coupling state, the parking lock coupling halves are rotationally fixed to one another, particularly by means of or via the parking lock element, whereby the connecting shaft and, in particular, the first planet carrier and also the second planet carrier can be rotationally fixed to the housing. This engages the parking lock, thus activating it.In the parking lock decoupling state, the parking lock allows relative rotations around the connecting shaft's axis of rotation between the parking lock coupling halves, and thus between the connecting shaft and the housing, and consequently between the first planet carrier and the housing. Therefore, the parking lock is designed to be deactivated in the parking lock decoupling state. For example, the parking lock element may be one of the parking lock coupling halves, or the parking lock element may be provided in addition to the parking lock coupling halves.

[0017] Furthermore, according to the invention, a connection point for the rotationally fixed connection of the connecting shaft to the first planet carrier is arranged between the first planet gear set and the second planet gear set with respect to the axial direction. In particular, the connection point is a location where the connecting shaft can be rotationally fixed to the first planet carrier. It is also conceivable that the connection point is a location where the connecting shaft is permanently, and in particular permanently, connected to the first planet carrier. For example, the connecting shaft and the first planet carrier are formed separately from one another and are permanently, and in particular permanently, connected to each other at the connection point in a rotationally fixed manner.

[0018] The first output shaft is rotatable about a first output shaft axis of rotation relative to the housing. The second output shaft is rotatable about a second output shaft axis of rotation relative to the housing. Preferably, the output shafts are arranged coaxially with each other, so that their output shaft axes of rotation coincide. Preferably, the respective output shaft axis of rotation runs parallel to the respective machine axis of rotation and / or parallel to the respective planetary gear set axis of rotation. Most preferably, the respective output shaft axis of rotation coincides with the respective machine axis of rotation and / or with the respective planetary gear set axis of rotation. If the parking lock is engaged, it is in its engaged state. If the parking lock is disengaged, it is in its disengaged state.

[0019] The first switching element has, for example, a first switching element coupling half that is permanently and rotationally fixed to the planet carrier; this coupling half is also referred to, for example, as the first switching half on the coupling gear side. Furthermore, the first switching element has, for example, a second switching element coupling half, which is also referred to, for example, as the second switching half. For example, the second switching element coupling half of the first switching element is permanently and rotationally fixed to the first rotor. It is conceivable that the first switching action of the first switching element is one of the switching element coupling halves of the first switching element, or that the first switching part of the first switching element is provided in addition to the switching element coupling halves of the first switching element.

[0020] The invention enables such an advantageous integration of the parking lock into the electric drive system, saving space, cost, and weight, that the parking lock, when engaged, acts on both output shafts simultaneously via the connecting shaft and the planetary carriers. Thus, when the parking lock is engaged, both output shafts are secured against rotation about their respective output shaft axis and relative to the housing by means of the same parking lock. Therefore, the invention allows both output shafts to be secured against unwanted rotation by means of the same parking lock, preventing the vehicle from rolling away when the parking lock is engaged.For this purpose, it is provided, for example, that a first of the drive wheels is permanently connected to the first output shaft in a torque-transmitting manner, and a second of the drive wheels is permanently connected to the second output shaft in a torque-transmitting manner. Thus, for example, the parking lock, when engaged, acts on both drive wheels simultaneously, thereby securing the drive wheels against rotation relative to the housing and, in particular, relative to the vehicle body. This allows the vehicle to be secured against unwanted rolling away.The vehicle's structure, designed, for example, as a self-supporting body, forms the interior, also known as the passenger compartment or passenger cell, in which people such as the driver can be present during a journey. The invention makes it possible to use the same parking lock for both output shafts and thus for both wheels of the vehicle, in order to secure the output shafts and therefore the wheels against unwanted rotation, even though the electric drive system is designed as a dual drive. With conventional dual drives, a separate parking lock is required for each electric motor or each drive wheel, which can now be avoided by the invention.This allows the number of parts, and therefore the weight, costs and installation space requirements of the electric drive system, to be kept to a particularly low level.

[0021] In an advantageous embodiment of the invention, the first coupling half, i.e., the first parking lock coupling half, is arranged between the coupling gear and the second rotor with respect to the axial direction of the electrical drive system. This allows for a particularly advantageous design in the axial direction of the drive system, such that the parking lock, when engaged, can act simultaneously on both output shafts, while keeping the axial length of the drive system especially short.

[0022] Another embodiment is characterized by a second switching element, provided in addition to the first switching element, which is designed to connect the first rotor to the second sun gear in a rotationally fixed manner. In other words, the first rotor can be connected to the second sun gear in a rotationally fixed manner by means of the second switching element. This allows for particularly advantageous maneuverability in a space-saving manner. In particular, the second switching element is switchable between a second coupling state and a second decoupling state. In the second coupling state, the first rotor is connected to the second sun gear in a rotationally fixed manner by means of the second switching element. In the second decoupling state, the second switching element allows relative rotations between the first rotor and the second sun gear about the first axis of rotation of the machine or about the second axis of rotation of the planetary gear set.For example, the second switching element has a second switching part which is movable, in particular translationally and / or relative to the housing, between at least one second coupling position that effects the second coupling state and at least one second decoupling position that effects the second decoupling state.

[0023] For example, the second switching element has a third switching element coupling half, which is, for example, and in particular permanently, rotationally fixed to the second sun gear. In this case, the third switching element coupling half is provided in addition to the first switching element coupling half of the first switching element. For example, the second switching element has a fourth switching element coupling half, which is, for example, and in particular permanently, rotationally fixed to the first rotor. It is conceivable that the fourth switching element coupling half is provided in addition to the second switching element coupling half, or that the fourth switching element coupling half is the second switching element coupling half. For example, the second switching element is one of the switching element coupling halves of the second switching element, or the second switching element is provided in addition to the switching element coupling halves of the second switching element.The use of the second switching element allows for advantageous drivability, and the parking lock can be integrated particularly advantageously into the drive system.

[0024] In order to integrate the parking lock particularly advantageously into the drive system, especially in such a way that the parking lock, when engaged, can act simultaneously on both output shafts and thus on both drive wheels, an advantageous embodiment of the invention provides that, with respect to the axial direction of the electric drive system, the coupling-side, first switching half of the first switching element, i.e., the first switching element coupling half of the first switching element, is arranged between the third switching element coupling half of the second switching element and the second rotor. The third switching element coupling half of the second switching element is also referred to as the coupling-side, third switching half of the second switching element, and the fourth switching element coupling half of the second switching element is also referred to as the rotor-side, fourth switching half of the second switching element.

[0025] To achieve particularly advantageous drivability in a space-saving manner, a further embodiment of the invention provides that the electric drive system has a third switching element, which is preferably provided in addition to the first and second switching elements. The third switching element is designed to connect the second rotor to the first sun gear in a rotationally fixed manner. In other words, the third switching element allows the second rotor to be connected to the first sun gear in a rotationally fixed manner. The third switching element can, for example, be switched between a third coupling state and a third decoupling state.In the third coupled state, the second rotor is rotationally fixed to the first sun gear by means of the third switching element, thus preventing relative rotations between the second rotor and the first sun gear about the second axis of rotation of the machine or about the first axis of rotation of the planetary gear set. In the third uncoupled state, the third switching element allows relative rotations between the second rotor and the first sun gear about the second axis of rotation of the machine or about the first axis of rotation of the planetary gear set. For example, the third switching element has a third switching part which is movable, particularly relative to the housing and / or translationally, between at least one third coupled position that effects the third coupled state and at least one third uncoupled position that effects the third uncoupled state.For example, the third switching element has a fifth switching element coupling half, which is permanently and rotationally fixed to the first sun gear and is also referred to as the fifth switching half on the coupling gear side. Furthermore, for example, the third switching element has a sixth switching element coupling half, which is permanently and rotationally fixed to the second rotor and is also referred to as the sixth switching half on the rotor side of the third switching element. The third switching element is, for example, one of the switching element coupling halves of the third switching element, or the third switching element of the third switching element is provided in addition to the switching element coupling halves of the third switching element. For example, the respective switching element can be moved in the axial direction of the electric drive system between the respective coupling position and the respective decoupling position.

[0026] In order to integrate the parking lock particularly advantageously into the electric drive system, especially in such a way that the parking lock in its engaged state acts simultaneously on both output shafts and thus simultaneously on both drive wheels, it is provided in a further, advantageous embodiment of the invention that, with regard to the axial direction, the coupling-drive-side, fifth switching half of the third switching element is arranged between the coupling-drive-side, first switching half of the first switching element and the second rotor.

[0027] Another embodiment is characterized by the fact that the first coupling half of the parking lock is permanently and rotationally fixed to the connecting shaft. This allows the parking lock to be integrated into the drive system in a particularly space-saving, lightweight, and cost-effective manner.

[0028] Finally, it has proven particularly advantageous if the second coupling half of the parking lock, i.e., the second parking lock coupling half, is permanently and rotationally fixed to the housing, at least with respect to one axis of rotation about which, in the designed state of the parking lock, the first coupling half is rotatable relative to the housing of the electric drive system. Specifically, this axis of rotation is the axis of rotation of the connecting shaft. This means that relative rotations between the second switching element coupling half and the housing, at least about this axis of rotation, are prevented, so that the first switching element coupling half can be fixed to the housing in a particularly simple and space-saving manner via this connecting shaft.

[0029] A second aspect of the invention relates to a motor vehicle, also simply referred to as a vehicle, which is preferably designed as a motor car, in particular as a passenger car, and has at least or exactly one electric drive system according to the first aspect of the invention and is capable of being driven electrically by means of the electric drive system, in particular purely electrically. Advantages and advantageous embodiments of the first aspect of the invention are to be regarded as advantages and advantageous embodiments of the second aspect of the invention and vice versa.

[0030] The names in this disclosure, also referred to as ordinals, such as "first", "first", "second", "second", etc., are not necessarily used to indicate or imply a number or quantity of components, but rather to clearly refer to terms to which the ordinal number words are assigned or to which the ordinal number words refer. Furthermore, the feature "axially overlapping" means the following: Two elements are arranged in an axially overlapping manner, particularly with respect to each other, if they are located in regions with the same axial coordinates.Thus, with regard to two axially overlapping elements, there exists a radially arranged straight line, that is, a line running in the radial direction of the electrical drive system and therefore perpendicular to the respective machine axis of rotation or the respective planetary gear set axis of rotation, which penetrates or intersects both of the axially overlapping elements. The radial direction of the electrical drive system is perpendicular to the axial direction of the electrical drive system. When the term "radial direction" is used below, it refers, unless otherwise specified, to the radial direction of the electrical drive system. Therefore, unless otherwise stated, the term "radial" refers to the radial direction of the electrical drive system.In other words, unless otherwise specified, the term "radial" refers to the radial direction of the electric drive system.

[0031] Further advantages, features, and details of the invention will become apparent from the following description of a preferred embodiment and from the drawing. The features and combinations of features mentioned above in the description, as well as those mentioned below in the figure description and / or shown in the figures alone, can be used not only in the combinations specified, but also in other combinations or individually, without departing from the scope of the invention.

[0032] The drawing shows in: Fig. 1 a schematic representation of an electric drive system for a motor vehicle, and Fig. 2. A switching table to illustrate different operating modes of the electric drive system.

[0033] In the figures, identical or functionally equivalent elements are provided with the same reference symbols.

[0034] Fig. Figure 1 shows a schematic representation of an electric drive system 10 for a motor vehicle, also referred to simply as a vehicle. The electric drive system 10 comprises a first electric machine 12, which has a first rotor 14 and a first stator 16. In the embodiment shown in the figures, the first electric machine 12 is designed as an axial flux machine. The rotor 14 can be driven by means of the stator 16 and is thereby rotatable about a first machine axis of rotation 18 relative to the stator 16. The electric drive system 10 also includes a second electric machine 20, which in the embodiment shown in the figures is designed as an axial flux machine (AFM). The second electric machine 20 has a second rotor 22 and a second stator 24. The rotor 22 can be driven by means of the stator 24 and is thereby rotatable about a second machine axis of rotation 26 relative to the stator 24.It can be seen that the electrical machines 12 and 20 are arranged coaxially to each other, so that the machine rotation axes 18 and 26 coincide. This is shown particularly schematically in [reference missing]. Fig. 1 is also a housing 28 of the electric drive system 10. For example, the respective electric machine 12, 20 is at least partially arranged in the housing 28. The rotors 14 and 22 are rotatable about the respective machine axis of rotation 18, 26 relative to the housing 28.

[0035] The electric drive system 10 comprises a planetary gear transmission 30. For example, the gear transmission 30 is at least partially arranged in the housing 28. For example, the electric drive system 10 is part of an axle 32 of the motor vehicle, also referred to as a vehicle axle or drive axle. The axle 32 has, in particular, two vehicle wheels 34 and 36, which are arranged on opposite sides of the vehicle in the transverse direction. The transverse direction is illustrated by a double arrow 38. The vehicle wheels 34 and 36, also simply referred to as wheels or drive wheels, are ground contact elements by means of which the motor vehicle can be supported or is supported downwards against a section of the ground in the vertical direction of the vehicle.When the motor vehicle is driven along the ground, and is supported downwards in the upward direction by the drive wheels, the drive wheels roll against the ground, in particular directly. The vehicle wheels 34 and 36 can be driven electrically via the coupling gear 30 by the respective electric motor 12, 20, in particular purely electrically, so that the vehicle wheels 34 and 36 are also referred to as drive wheels.

[0036] The linkage 30 comprises a first planetary gear set 40, which includes a first ring gear 42, a first planet carrier 44, and a first sun gear 46. The ring gear 42, the planet carrier 44, and the sun gear 46 are gear elements of the first planetary gear set 40, wherein each gear element is rotatable about a first planetary gear set axis of rotation 48 relative to the housing 28, particularly when it is not rotationally fixed to the housing 28. The linkage 30 comprises a second planetary gear set 50, which includes a second ring gear 52, a second planet carrier 54, and a second sun gear 56. The ring gear 52, the planet carrier 54 and the sun gear 56 are planet gear set elements of the second planet gear set 50, wherein the respective planet gear set element is rotatable about a second planet gear set axis of rotation 58 relative to the housing 28 when it is not rotationally fixed to the housing 28.The planetary gear sets 40 and 50 are arranged coaxially with each other, so that the planetary gear set axes of rotation 48 and 58 coincide. Furthermore, the planetary gear sets 40 and 50 are arranged coaxially with the electric machines 12 and 20, so that the planetary gear set axes of rotation 48 and 50 coincide with the machine axes of rotation 18 and 26. First planet gears 60 and second planet gears 62 are arranged, i.e., held, on the first planet carrier 44, with the first planet gears 60 meshing, in particular permanently, with the first sun gear 46. The second planets 162 mesh in particular permanently with the ring gear 42, and each of the first planet gears 60 meshes, in particular permanently, with, in particular exactly, one of the respective second planet gears 60. For example, each second planet gear 62 has a respective first toothing that meshes, in particular permanently, with the ring gear 42 and with the respective first planet gear 60.The respective planet gear 62 does not mesh with the sun gear 46. The respective planet gear 60 does not mesh with the ring gear 42. The second planet gears 62 are rotatably mounted on the second planet carrier 54, and third planet gears 64 are rotatably mounted on the second planet carrier 54. The second planet gears 62 mesh, in particular permanently, with the sun gear 56. The third planet gears 64 mesh, in particular permanently, with the ring gear 52. Furthermore, each of the planet gears 62 meshes, in particular permanently, and in particular precisely, with one of the respective third planet gears 64. The respective second planet gear 62, for example, has a second set of teeth, in particular in addition to the respective first set of teeth, which meshes with the sun gear 56 and the respective third planet gear 64.The respective planet gear 60, for example, does not mesh with the ring gear 42, and the respective planet gear 62, for example, does not mesh with the sun gear 46. The respective planet gear 62, for example, does not mesh with the ring gear 52, and the respective planet gear 64, for example, does not mesh with the sun gear 56. In particular, the respective second planet gear 62 is designed as a stepped planet gear.

[0037] The first planet carrier 44 is permanently and rotationally fixedly connected to the second planet carrier 54. With respect to the axial direction of the electric drive system 10, the first electric machine 12 is arranged on the first side S1 of the coupling gear 30, which is facing away from the second electric machine 20 in the axial direction of the electric drive system 10. The second electric machine 20 is arranged on the second side S2 of the coupling gear 30, which is facing away from the first electric machine 12 and from the first side S1 in the axial direction of the electric drive system 10. When the axial direction is mentioned before and after, unless otherwise specified, this refers to the axial direction of the electric drive system 10, the radial direction of which is perpendicular to the axial direction.The axial direction of the electric drive system 10 coincides with the respective machine rotation axis 18, 26 and thus with the respective planetary gear set rotation axis 48, 58. The radial direction of the electric drive system 10 is in . Fig. 1 illustrated by a double arrow 66.

[0038] The electric drive system 10 has a first switching element SE1, which is designed to connect the first rotor 14 rotationally fixed to the second planet carrier 54 and via this rotationally fixed to the first planet carrier 44.

[0039] Furthermore, the electric drive system 10 has a connecting shaft 67, which is designed to connect the first planet carrier 44 in a rotationally fixed manner to a first coupling half K1 of a parking lock 72 of the electric drive system 10. The first coupling half K1 is permanently and rotationally fixed to the first planet carrier 44 by means of the connecting shaft 67. This means that the drive system 10 has the parking lock 72, which comprises the first coupling half K1 and a second coupling half K2. The first coupling half K1 is also referred to as the first parking lock coupling half, and the second coupling half K2 is also referred to as the second parking lock coupling half.

[0040] The parking lock 72 can be switched between an engaged state and an disengaged state. In its engaged state, the parking lock 72 is engaged, i.e., activated, and in its disengaged state, the parking lock 72 is disengaged, i.e., deactivated. The engaged state is also referred to as the parking lock coupling state, and the disengaged state is also referred to as the parking lock disengaged state. In the engaged state of the parking lock 72, the coupling halves K1 and K2 are rotationally fixed to one another. In the disengaged state, the parking lock 72 allows relative rotation between the coupling halves K1 and K2. In the disengaged state, the coupling halves K1 and K2 are rotatable relative to each other about a pivot axis 69, where the pivot axis 69 coincides with the machine pivot axes 18 and 26 and the planetary gear set pivot axes 48 and 58.The second coupling half K2 is fixed to the housing 28, at least with respect to rotations about the axis of rotation and relative to the housing 28, such that the second coupling half K2 is rotationally fixed to the housing 28, at least with respect to rotations about the axis of rotation 69. Thus, in the engaged state of the parking lock 72, the coupling half K1 is rotationally fixed to the coupling half K2 and therefore rotationally fixed to the housing 28, and in the disengaged state of the parking lock 72, the coupling half K1 is rotatable about the axis of rotation 69 relative to the housing 28 and relative to the coupling half K2.

[0041] At the in Fig. In the embodiment shown in Figure 1, the coupling half K1 is connected, in particular permanently, to the connecting shaft 67 in a rotationally fixed manner, which is rotatable about a connecting shaft axis of rotation 73 relative to the housing 28, particularly in the deployed state of the parking lock 72. In the engaged state of the parking lock 72, the connecting shaft 67 is connected to the housing 28 in a rotationally fixed manner, in particular via the parking lock 72.

[0042] The coupling mechanism 30, and thus the electric drive system 10, comprises a first output shaft 68, which is permanently and rotationally fixed to the first ring gear 42 and is designed to transmit torques, also referred to as first rotating elements, from the coupling mechanism 30, bypassing the planet carriers 44 and 54 and the sun gears 46 and 56. The coupling mechanism 30, and thus the electric drive system 10, also comprises a second output shaft 70, which is permanently and rotationally fixed to the second ring gear 52 and is designed to transmit torques, also referred to as second rotating elements, from the coupling mechanism 30, bypassing the planet carriers 44 and 54 and the sun gears 46 and 56. It can be seen that the vehicle wheel 34 can be driven by the output shaft 68 and thus via the output shaft 68 by the coupling gear 30 and via this by the respective electric machine 12, 20.Accordingly, the vehicle wheel 36 can be driven by the output shaft 70 and thus, via the output shaft 70, by the coupling gear 30 and, via this, by the respective electric machine 12, 20. For example, the coupling gear 30 is, forms, or comprises a particularly central superposition unit by means of which a respective first drive torque, provided or makeable by the electric machine 12 via its rotor 14 and intended for driving the vehicle wheels 34 and 36, can be superimposed with a respective second drive torque, provided or makeable by the electric machine 20 via its rotor 22 and intended for driving the vehicle wheels 34, 36, so that a particularly efficient drive of the motor vehicle can be represented.

[0043] Furthermore, in the drive system 10, a connection point AS for the rotationally fixed connection of the connecting shaft 67 to the first planet carrier 44 is arranged between the first planet gear set 40 and the second planet gear set 50 with respect to the axial direction. Fig. Figure 1 shows that, for example, the connecting shaft 67 is permanently and rotationally fixedly connected to the planet carrier 44 at the connection point AS. The connecting shaft 67 is, for example, formed separately from the planet carrier 44 and is permanently and rotationally fixedly connected to the planet carrier 44 at the connection point AS, and in particular via the planet carrier 44 to the planet carrier 54.

[0044] The switching element SE1 has a first switching element coupling half SK1 on the coupling gear side and a second switching element coupling half SK2 on the rotor side. The coupling gear-side switching element coupling half SK1 is also referred to as the first switching half, and the rotor-side second switching element coupling half SK2 is also referred to as the second switching half. It can be seen that the first switching element coupling half SK1 is connected, in particular permanently, to the second planet carrier 54 in a rotationally fixed manner, and the second switching element coupling half SK2 is connected, in particular permanently, to the first rotor 14 in a rotationally fixed manner.The switching element SE1, for example, has a first switching part which is movable, in particular translationally and / or relative to the housing 28 and / or in the axial direction of the drive system 10, between at least one first coupling position, which moves the switching transmission SE1 into a first coupling state, and at least one first decoupling position, which effects a first decoupling state of the switching element SE1. In the first coupling state, the first rotor 14 is rotationally fixed to the second planet carrier 54 by means of the first switching element SE1. In the first decoupling state, the first switching element SE1 transmits a relative torque about the machine axis of rotation 18 between the planet carrier 54 and the first rotor 14. It is conceivable that the first switching part is provided in addition to the switching element coupling halves SK1 and SK2, or that the first switching part is, for example, the switching element coupling half SK2.

[0045] The switching element coupling halves are advantageously either jaw teeth of a jaw coupling or friction elements of a friction coupling. For example, the first switching element coupling half SK1 is a coupling-side jaw toothing, while the second switching element coupling half SK2 is a rotor-side (relative to the first rotor 14) jaw toothing.

[0046] At the in Fig. In the embodiment shown in Figure 1, the first coupling half K1 is arranged between the coupling gear 30 and the second rotor 22 with respect to the axial direction of the electric drive system 10.

[0047] The electric drive system 10 has a second switching element SE2, which is designed to connect the first rotor 14 to the second sun gear 56 in a rotationally fixed manner. For this purpose, the switching element SE2 is switchable between a second coupling state and a second decoupling state. In the second coupling state, the first rotor 14 is rotationally fixed to the second sun gear 56 by means of the second switching element SE2, and in the second decoupling state, the second switching element SE2 transmits the relative torque about the machine's axis of rotation 18 between the first rotor 14 and the second sun gear 56.The switching element SE2, for example, has a second switching part which is movable, in particular translationally and / or relative to the housing 28 and / or in the axial direction of the electric drive system 10, between at least one second coupling position that effects the second coupling state and at least one second decoupling position that effects the second decoupling state. The second switching element SE2 has a third switching element coupling half SK3 on the coupling gear side, which is also referred to, for example, as the coupling gear-side third switching half. Furthermore, the switching element SE2 has, for example, a fourth switching element coupling half SK4 on the rotor side, which is referred to as the rotor-side fourth switching half.The second switching element can be provided in addition to the switching element coupling halves SK3 and SK4, or the second switching element can be one of the switching element coupling halves SK3 and SK4, and in particular the fourth switching element coupling half SK4. It is apparent that the switching element coupling halves SK2 and SK4 can be connected to each other in such a way that they can, for example, be moved back and forth together between their respective coupled and uncoupled positions. In particular, it is conceivable that the switching element coupling half SK2 is the switching element coupling half SK4, or vice versa, so that, for example, the switching elements SE1 and SE2 have a common switching element that can be moved between their respective coupled and uncoupled positions.In this case, the first coupling state is accompanied by the second decoupling state, and vice versa, in particular because the first coupling state is accompanied by the second decoupling state and vice versa. Thus, for example, switching element SE2 is always in its second decoupling state when switching element SE1 is in its first coupling state. And, for example, switching element SE2 is always in its second coupling state when switching element SE1 is in its first decoupling state.

[0048] The electric drive system 10 also includes a third switching element SE3, which is configured to connect the second rotor 22 to the first sun gear 46 in a rotationally fixed manner. Thus, for example, the switching element SE3 can be switched between a third coupling state and a third decoupling state. In the third coupling state, the second rotor 22 is rotationally fixed to the first sun gear 46 by means of the third switching element SE3, and in the third decoupling state, the third switching element SE3 releases the second rotor 22 and the first sun gear 46 for relative torque about the machine's axis of rotation 26.

[0049] With respect to the axial direction of the electric drive system, the coupling-gear-side first switching element coupling half SK1 of the switching element SE1 is arranged between the coupling-gear-side third switching element coupling half SK3 of the second switching element SE2 and the second rotor 22. The third switching element SE3 has a coupling-gear-side fifth switching element coupling half SK5, which is also referred to as the coupling-gear-side fifth switching half. Furthermore, for example, the switching element SE3 has a rotor-side sixth switching element coupling half SK6, which is also referred to as the rotor-side sixth switching half. In particular, the switching element coupling half SK5 of the third switching element SE3 is, in particular, permanently and rotationally fixed to the first sun gear 46. For example, the sixth switching element coupling half SK6 of the third switching element SE3 is, in particular, permanently and rotationally fixed to the rotor 22.In this case, it is provided that, with regard to the axial direction of the electric drive system 10, the coupling gear-side fifth switching element coupling half SK5 of the third switching element SE3 is arranged between the coupling gear-side first switching element coupling half SK1 of the first switching element SE1 and the second rotor 22.

[0050] The drive system 10 has a first transmission stage 74, which, with respect to a first torque flow along which the respective first torque from the first output shaft 68 to the first vehicle wheel 34 can be transmitted, is arranged downstream of the first output shaft 68 and downstream of the coupling gear 30 and upstream of the vehicle wheel 34 in the first torque flow. Accordingly, the drive system 10 has a second transmission stage 78, which, with respect to a second torque flow along which the respective second torque from the output shaft 70 to the second vehicle wheel 36 can be transmitted, is arranged downstream of the second output shaft 70 and downstream of the coupling gear 30 and upstream of the second vehicle wheel 36 in the second torque flow.For example, each transmission stage 74, 78 is designed as a third planetary gear set, comprising a third sun gear 80, a third planet carrier 82, and a third ring gear 84. Further planet gears 86 are rotatably arranged on each planet gear 82, i.e., held in place, such that each planet gear 86 meshes simultaneously with the sun gear 80 and the ring gear 84 of each transmission stage 74, 78. In this case, the first output shaft 68 is permanently and rotationally fixed to the sun gear 80 of transmission stage 74, and the second output shaft 70 is permanently and rotationally fixed to the sun gear 80 of transmission stage 78. The ring gear 84 is permanently and rotationally fixed to the housing 28.The respective planet carrier 82 is, in particular, permanently and rotationally fixed to a respective, further shaft 88, from which the respective vehicle wheel 34, 36 can be driven. In particular, the respective shaft 88 is permanently torque-transmitting and, in particular, permanently rotationally fixed to the respective vehicle wheel 34, 36.

[0051] Fig. Figure 2 shows a switching table illustrating different modes, also referred to as operating modes, in which the drive system 10 can be operated or switched. The in Fig.The two modes, designated M1, M2, M3, and M4, are entered in column SP1 of the switching table, and the parking lock (designated P) and the switching elements SE1, SE2, and SE3 are entered in row Z1. In the first mode, M1, the parking lock 72 is engaged, thus securing the vehicle against unwanted rolling away. For this to occur, the parking lock 72 is in its engaged state, while the switching elements SE1, SE2, and SE3 are in their disengaged states.

[0052] The second mode M2, for example, is an efficiency mode in which the parking lock 72 is in its parking lock decoupling state, while the switching element SE1 is in its first coupling state and the switching elements SE2 and SE3 are in their decoupling states.

[0053] The third mode M3, for example, is a superposition mode in which the parking lock 72 is in its parking lock decoupling state, while the switching elements SE2 and SE3 are in their coupling states and the switching element SE1 is in its decoupling state.

[0054] The fourth mode, for example, is a torque displacement and summation mode in which the parking lock 72 is in its parking lock decoupling state, while the switching elements SE2 and SE3 are in their coupling states and the switching element SE1 is in its decoupling state. Reference symbol list 10 electric drive system 12 first electric machine 14 first rotor 16 first stator 18 first machine axis 20 second electric machine 22 second rotor 24 second stator 26 second machine axis 28 cases 30 coupling gears 32-axis 34 first vehicle wheel 36 second vehicle wheel 38 Double Arrow 40 first planetary gear set 42 first ring gear 44 first planetary carrier 46 first sun wheel 48 first planetary gear set pivot axis 50 second planetary gear set 52 second ring gear 54 second planetary carrier 56 second sun wheel 58 second planetary gear set pivot axis 60 first planetary gear 62 second planetary gear 64 third planetary gear 66 Double Arrow 67 Connecting shaft 68 first output shaft 69 Connecting shaft pivot axis 70 second output shaft 72 Parking restrictions 73 Axis of rotation 74 first translation stage 78 second translation stage 80 third sun wheel 82 third planetary carrier 84 third ring gear 88 wave S1 first page S2 second page K1 first clutch half K2 second clutch half AS connection point SK1 first switching element coupling half SK2 second switching element coupling half SK3 third switching element coupling half SK4 fourth switching element coupling half SK5 fifth switching element coupling half SK6 sixth switching element coupling half P Parking barrier SE1 first switching element SE2 second switching element SE3 third switching element SP1 column Z1 line M1 first mode M2 second mode M3 third mode M4 fourth mode

Claims

[1] Electric drive system (10) for a motor vehicle, comprising a first electric machine (12) with a first rotor (14), a second electric machine (20) with a second rotor (22), and a planetary coupling gear (30), wherein: - the coupling gear (30) comprises a first planet gear set (40) with a first ring gear (42), a first planet carrier (44) and a first sun gear (46) and a second planet gear set (50) with a second ring gear (52), a second planet carrier (54) and a second sun gear (56); - the first planet carrier (44) is connected to the second planet carrier (54) in a rotationally fixed manner; - a first output shaft (68) of the coupling gear (30) is provided, which is non-rotatably connected to the first ring gear (42), and whose first output shaft (68) is designed to transmit torques from the coupling gear (30) by bypassing the planet carriers (44, 54) and the sun gears (46, 56); - a second output shaft (70) of the coupling gear (30) is provided, which is non-rotatably connected to the second ring gear (52), and whose second output shaft (70) is designed to transmit torques from the coupling gear (30) by bypassing the planet carriers (44, 54) and the sun gears (46, 56); characterized by , that - with respect to an axial direction coinciding with a machine rotation axis (18, 26), the first electric machine (12) is arranged on a side (S1) of the coupling gear (30) facing away from the second electric machine (20); - a connecting shaft (67) is provided, which is designed to connect the first planet carrier (44) rotationally fixedly to a first coupling half (K1) of a parking lock (72); and - a connection point (AS) for the rotationally fixed connection of the connecting shaft (67) to the first planet carrier (44) with respect to the axial direction is arranged between the first planet gear set (40) and the second planet gear set (50). [2] Electric drive system (10) according to claim 1, characterized by , that the first coupling half (K1) is arranged with respect to the axial direction between the coupling gear (30) and the second rotor (22). [3] Electric drive system (10) according to claim 1 or 2, characterized by a first switching element (SE1) which is designed to connect the first rotor (14) to the second planet carrier (54) in a rotationally fixed manner, and by a second switching element (SE2) which is designed to connect the first rotor (14) to the second sun gear (56) in a rotationally fixed manner. [4] Electric drive system (10) according to claim 3, characterized by , that with respect to the axial direction a coupling gear-side switching half (SK1) of the first switching element (SE1) is arranged between a coupling gear-side switching half (SK3) of the second switching element (SE2) and the second rotor (22). [5] Electric drive system (10) according to any one of the preceding claims, characterized by a third switching element (SE3) which is designed to connect the second rotor (22) to the first sun wheel (46) in a rotationally fixed manner. [6] Electric drive system (10) according to claim 5, characterized by , that with respect to the axial direction a coupling gear-side switching half (SK5) of the third switching element (SE) is arranged between the two planet gear sets (40, 50) and the second rotor (22). [7] Electric drive system (10) according to any one of the preceding claims, characterized by , that the first coupling half (K1) of the parking lock (72) is permanently connected to the connecting shaft (67) in a rotationally fixed manner. [8] Electric drive system (10) according to any one of the preceding claims, characterized by , that a second coupling half (K2) of the parking lock (72) is permanently and rotationally fixed to the housing (28) at least with respect to an axis of rotation about which the first coupling half (K1) is rotatable relative to a housing (28) of the electric drive system. [9] Motor vehicle, comprising at least one electric drive system (10) according to any of the preceding claims.

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