Electric drive system for a motor vehicle and motor vehicle

Abstract

An electric drive system (10) for a motor vehicle, comprising a first electric machine (18) having a first rotor (20), a second electric machine (26) having a second rotor (28), a first vehicle wheel (14), a second vehicle wheel (16), a first gear stage (34) designed to couple the first rotor (20) to the first vehicle wheel (14) in a torque-transmitting manner, a second gear stage (36) designed to couple the second rotor (28) to the second vehicle wheel (16) in a torque-transmitting manner, a first parking lock gear (44), a second parking lock gear (46), a first parking lock pawl (48) for locking the first parking lock gear (44), and a second parking lock pawl (50) for locking the second parking lock gear (46), characterized in that: - the first rotor (20) is arranged coaxially to the second rotor (28), - the first parking lock gear (44) is coupled to a first planet carrier (56a) of the first gear ratio (34) in a torque-transmitting manner, - the second parking lock gear (46) is coupled to a second planet carrier (56b) of the second gear stage (36) in a torque-transmitting manner and is arranged coaxially to the first parking lock gear (44), wherein exactly one coupling shaft (62) is provided which is rotatable about a coupling shaft rotation axis (64) and via which the two parking lock pawls (48, 50) can be actuated, wherein the first parking lock pawl (48) and the second parking lock pawl (50) are arranged to be rotatable about a common pawl rotation axis (60), where - a first eccentric element (66) is elastically connected to the coupling shaft (62) and pivotable by rotating the coupling shaft (62), by means of which the first parking lock pawl (48) can be actuated by pivoting the first eccentric element (66) and can thereby be rotated about the pawl rotation axis (60), wherein, if a resistance acts on the first eccentric element (66), the rotation of the first eccentric element (66) can be delayed relative to the coupling shaft (62); and - a second eccentric element (68) is elastically connected to the coupling shaft (62) and pivotable by rotating the coupling shaft (62), by means of which the second parking lock pawl (50) can be actuated by pivoting the second eccentric element (68) and can thereby be rotated about the pawl rotation axis (60), wherein, if a resistance acts on the second eccentric element (68), the rotation of the second eccentric element (68) can be delayed relative to the coupling shaft (62).

Description

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

[0002] WO 2022 / 049285 A1 discloses a drive block for an electric motor drive of a motor vehicle, comprising a first electric motor and a first transmission arranged on the front side of the first electric motor. A second electric motor and a second transmission arranged on the front side of the second electric motor are also provided.

[0003] DE 20 2009 014 189 U1 discloses an electric drive system for a motor vehicle comprising two coaxially arranged electric motors, each of which drives a wheel of the motor vehicle via an intermediate transmission. One of the two transmissions includes a parking lock system.

[0004] WO 2017 / 051 719 A1, KR 10 2022 0 040 218 A, DE 10 2021 202 692 A1 and JP 2009 - 137 427 A show parking lock systems each with two parking lock pawls, wherein the two parking lock pawls are actuated via a single coupling shaft.

[0005] The object of the present invention is to provide an electric drive system for a motor vehicle and a motor vehicle with such an electric drive system, so that a parking lock can be realized in a particularly cost-effective and space-saving manner.

[0006] This object is achieved by an electric drive system having the features of patent claim 1 and by a motor vehicle having the features of patent claim 8. Advantageous embodiments with expedient further developments of the invention are specified in the remaining claims.

[0007] A first aspect of the invention relates to an electric drive system, also referred to as an electric drive device, for a motor vehicle, also simply referred to as a vehicle, which is preferably designed as a motor vehicle, in particular as a passenger car. This means that the motor vehicle, in its fully manufactured state, has the electric drive system and can be driven, in particular purely electrically, by means of the electric drive system. The electric drive system has a first electric machine, which has a first rotor. Preferably, the first electric machine also has a first stator, by means of which the first rotor can be driven and is thus rotatable about a first machine axis of rotation relative to the first stator. In particular, the first electric machine can provide first drive torques for driving the motor vehicle, in particular purely electrically, via its first rotor.The electric drive system also has a second electric machine with a second rotor. For example, the second electric machine also has a second stator, by means of which the second rotor can be driven and is thus rotatable about a second motor axis of rotation relative to the second stator. Preferably, the electric machines and thus the rotors are arranged coaxially to one another so that the motor axes of rotation coincide. In particular, the motor axes of rotation thus coincide with a main axis of rotation of the electric drive system. In other words, the respective rotor is rotatable about the main axis of rotation relative to the respective stator. In particular, the second electric machine can provide second drive torques via its second rotor for driving the motor vehicle, in particular purely electrically. The electric drive system also has a first vehicle wheel and a second vehicle wheel.The vehicle wheels are also simply referred to as wheels. In particular, the vehicle wheels are vehicle wheels of the same vehicle axle of the motor vehicle. Preferably, the motor vehicle in its fully manufactured state has at least or exactly two vehicle axles, namely the aforementioned vehicle axle as the first vehicle axle and a second vehicle axle, wherein the vehicle axles are arranged consecutively in the longitudinal direction of the motor vehicle, i.e. one behind the other. The vehicle wheels, also simply referred to as wheels, are preferably arranged on opposite sides of the motor vehicle in the transverse direction of the motor vehicle. The vehicle wheels are ground contact elements by means of which the motor vehicle can be or is supported downwards on a ground in the vertical direction of the vehicle.If the motor vehicle is driven along the ground while the motor vehicle is supported downwards on the ground via the ground contact elements in the vertical direction of the motor vehicle, the ground contact elements roll, in particular directly, on the ground.

[0008] The electric drive system has a first gear ratio stage which is designed to couple the first rotor to the first vehicle wheel in a torque-transmitting manner, such that the first vehicle wheel can be driven by the first rotor and thus by the first electric machine, i.e. by the respective first drive torque, via the first gear ratio stage. In particular, it is conceivable that the first rotor is or can be coupled to the first gear ratio stage in a torque-transmitting manner, wherein it is particularly conceivable that the first rotor is permanently coupled to the first gear ratio stage in a torque-transmitting manner. Furthermore, it is conceivable that the first gear ratio stage can be or is coupled to the first vehicle wheel in a torque-transmitting manner, wherein it is possible for the first gear ratio stage to be permanently coupled to the first vehicle wheel in a torque-transmitting manner.Thus, it is conceivable that the first rotor is or can be coupled to the first vehicle wheel via the first gear ratio stage in a torque-transmitting manner, wherein it can be provided that the first rotor is permanently coupled to the first vehicle wheel via the first gear ratio stage in a torque-transmitting manner. The electric drive system also has a second gear ratio stage, which is designed to couple the second rotor to the second vehicle wheel in a torque-transmitting manner. Thus, it is possible that the second rotor is or can be coupled to the second gear ratio stage in a torque-transmitting manner, wherein it is conceivable that the second rotor is permanently coupled to the second gear ratio stage in a torque-transmitting manner.Furthermore, it is possible for the second gear ratio to be coupled or connected to the second vehicle wheel in a torque-transmitting manner, and it is possible for the second gear ratio to be permanently coupled to the second vehicle wheel in a torque-transmitting manner. Thus, it is possible for the second rotor to be coupled or connected to the second vehicle wheel in a torque-transmitting manner via the second gear ratio, and it is possible for the second rotor to be permanently coupled to the second vehicle wheel in a torque-transmitting manner via the second gear ratio.In particular, it is provided that the first rotor can be coupled or is coupled to the first vehicle wheel in a torque-transmitting manner via the first gear ratio stage, bypassing the second rotor, and bypassing the second gear ratio stage, bypassing the second vehicle wheel, so that, with respect to a first torque flow along which the respective first drive torque can be transmitted from the rotor to the second vehicle wheel via the first gear ratio stage, the first gear ratio stage is arranged downstream of the first rotor and upstream of the first vehicle wheel in the first torque flow, wherein the second rotor and thus the second gear ratio stage and the second vehicle wheel are not arranged downstream of the first rotor and upstream of the first vehicle wheel in the first torque flow.In particular, it is provided that the second rotor can be coupled or is coupled to the second vehicle wheel in a torque-transmitting manner via the second gear ratio stage, bypassing the first rotor, bypassing the first gear ratio stage and bypassing the first vehicle wheel, so that, with respect to a second torque flow along which the respective second drive torque can be transmitted from the second rotor to the second vehicle wheel via the second gear ratio stage, the second gear ratio stage is arranged downstream of the second rotor and upstream of the second vehicle wheel in the second torque flow, wherein the first rotor, the first gear ratio stage and the first vehicle wheel are not arranged downstream of the second rotor and upstream of the second vehicle wheel in the second torque flow.

[0009] The electric drive system comprises, for example, a housing, wherein the respective rotor is rotatable about the respective motor rotation axis relative to the respective stator and relative to the housing. It is conceivable that the first electric machine and / or the second electric machine and / or the first gear stage and / or the second gear stage are each arranged at least partially in the housing. The electric drive system comprises a first parking lock gear and a second parking lock gear.

[0010] For example, the first parking lock gear is rotatable relative to the housing about a first parking lock gear rotation axis. For example, the first parking lock gear is or can be coupled to the first vehicle wheel in a torque-transmitting manner. Very particularly, the first parking lock gear is permanently coupled to the first vehicle wheel in a torque-transmitting manner. For example, the first parking lock gear is or can be coupled to the first vehicle wheel in a torque-transmitting manner, bypassing the second parking lock gear and bypassing the second vehicle wheel. In particular, it is provided that the first parking lock gear is permanently coupled to the first vehicle wheel in a torque-transmitting manner, bypassing the second parking lock gear and bypassing the second vehicle wheel.In particular, the first parking lock gear is or can be coupled to the first vehicle wheel via the first gear ratio in a torque-transmitting manner. It can be provided, in particular, that the first parking lock gear is permanently coupled to the first vehicle wheel via the first gear ratio in a torque-transmitting manner. For example, the first parking lock gear is connected, in particular permanently and non-rotatably, to a first component of the first gear ratio, so that, for example, the first component and the first parking lock gear are rotatable relative to the housing about the first parking lock gear rotation axis.

[0011] For example, the second parking lock gear is rotatable relative to the housing about a second parking lock gear rotation axis. For example, the second parking lock gear is or can be coupled to the second vehicle wheel in a torque-transmitting manner. More particularly, the second parking lock gear is permanently coupled to the second vehicle wheel in a torque-transmitting manner. For example, the second parking lock gear is or can be coupled to the second vehicle wheel in a torque-transmitting manner, bypassing the first parking lock gear and bypassing the first vehicle wheel. In particular, it is provided that the second parking lock gear is permanently coupled to the second vehicle wheel in a torque-transmitting manner, bypassing the first parking lock gear and bypassing the first vehicle wheel.In particular, the second parking lock gear is or can be coupled to the second vehicle wheel via the second gear ratio in a torque-transmitting manner. It can be provided, in particular, that the second parking lock gear is permanently coupled to the second vehicle wheel via the second gear ratio in a torque-transmitting manner. For example, the second parking lock gear is connected, in particular permanently and non-rotatably, to a second component of the second gear ratio, so that, for example, the second component and the second parking lock gear are rotatable relative to the housing about the second parking lock gear rotation axis.

[0012] The electric drive system also has a first parking lock pawl for locking the first parking lock gear and a second parking lock pawl for locking the second parking lock gear. Thus, for example, the first parking lock pawl, which is also simply referred to as the first pawl, is movable relative to the housing between at least one first locking position and at least one first release position. In the first locking position, the first parking lock gear is locked by means of the first parking lock pawl, whereby rotations of the first parking lock gear about the first parking lock gear rotation axis and relative to the housing are prevented, i.e., avoided. In other words, in the first locking position of the first parking lock pawl, the first parking lock gear can no longer rotate relative to the housing about the first parking lock gear rotation axis.In the first release position, the first parking lock pawl releases the first parking lock gear for rotation about the first parking lock gear rotation axis and relative to the housing, so that in the first release position, the first parking lock gear can rotate about the first parking lock gear rotation axis relative to the housing. In particular, in the first locking position, the first parking lock pawl interacts with the first parking lock gear in a positively locking manner, so that in the first locking position, the first parking lock gear is positively locked by means of the first parking lock pawl. In other words, in the first locking state of the first parking lock pawl, the first parking lock gear is connected to the housing in a rotationally fixed manner, in particular in a positively locking manner.

[0013] The second parking lock pawl, also simply referred to as the second pawl, is movable relative to the housing between at least one second locking position and at least one second release position. In the second locking position, the second parking lock gear is locked by the second parking lock pawl, thereby preventing, i.e., preventing, rotation of the second parking lock gear about the second parking lock gear rotation axis and relative to the housing. In other words, in the second locking position of the second parking lock pawl, the second parking lock gear can no longer rotate relative to the housing about the second parking lock gear rotation axis.In the second release position, the second parking lock pawl releases the second parking lock gear for rotation about the second parking lock gear rotation axis and relative to the housing, so that in the second release position the second parking lock gear can rotate about the second parking lock gear rotation axis relative to the housing. In particular, in the second locking position the second parking lock pawl interacts with the second parking lock gear in a positively locking manner, so that in the second locking position the second parking lock pawl is positively locked by means of the second parking lock pawl. In other words, in the second locking state of the second parking lock pawl, the second parking lock gear is connected to the housing in a rotationally fixed manner, in particular in a positively locking manner.

[0014] The first parking lock gear and the first parking lock pawl are, for example, components of a first parking lock unit, and the second parking lock gear and the second parking lock pawl are, for example, components of a second parking lock unit, wherein the parking lock units are, for example, components of a parking lock. In the respective locked position of the respective parking lock pawl, the respective parking lock unit is engaged, i.e., activated. In the respective released position, the respective parking lock unit is disengaged, i.e., deactivated. If the parking lock units are engaged simultaneously, the entire parking lock is engaged. If the parking lock units are disengaged simultaneously, the parking lock is disengaged.If the first parking lock unit is engaged, the first vehicle wheel is secured against rotation about a first wheel rotation axis and relative to the housing, such that the first vehicle wheel can no longer rotate about the first wheel rotation axis relative to the housing. If the second parking lock unit is engaged, the second vehicle wheel is secured against rotation about a second wheel rotation axis and relative to the housing, such that the second vehicle wheel can no longer rotate about the second wheel rotation axis relative to the housing. If the first parking lock unit is disengaged, the first parking lock unit allows rotations about the first wheel rotation axis and relative to the housing, such that the first vehicle wheel can rotate about the first wheel rotation axis relative to the housing.If the second parking lock unit is engaged, the second parking lock unit permits rotation of the second vehicle wheel about the second wheel rotation axis and relative to the housing, allowing the second vehicle wheel to rotate about the second wheel rotation axis relative to the housing. If the parking lock units are thus engaged simultaneously, the motor vehicle can be secured against unwanted rolling away, for example, when parked on a slope, since the vehicle wheels cannot rotate about the wheel rotation axes relative to the housing. This prevents the motor vehicle from undesired rolling down the slope.

[0015] In order to be able to implement the parking lock in a particularly cost- and space-efficient manner and to ensure that the parking lock is particularly robust, so that the motor vehicle can be secured particularly securely against unwanted rolling away by means of the parking lock, the invention provides that the rotor is arranged coaxially to the second rotor, so that the machine axes of rotation coincide. Furthermore, the invention provides that the first parking lock gear is coupled, in particular permanently, to a first planet carrier of the first gear ratio stage in a torque-transmitting manner. Particularly advantageously, the first parking lock gear is connected in a rotationally fixed manner to the first planet carrier of the first gear ratio stage, so that the aforementioned first component of the first gear ratio stage is the first planet carrier of the first gear ratio stage.Furthermore, the invention provides that the second parking lock gear is coupled, in particular permanently, to a second planet carrier of the second gear ratio in a torque-transmitting manner. Particularly advantageously, the second parking lock gear is connected in a rotationally fixed manner to the second planet carrier of the second gear ratio, so that the aforementioned second component of the second gear ratio is the second planet carrier.

[0016] Thus, for example, the first gear ratio is a first planetary gear set, which is also referred to as a first planetary transmission. The first planetary gear set has at least one or exactly one first sun gear, at least one or exactly one first ring gear, and the first planet carrier. Furthermore, for example, the first planetary gear set has at least one first planetary gear, which is rotatably mounted on the first planet carrier and meshes, in particular directly, with the first sun gear and with the first ring gear, wherein direct meshing of the first sun gear with the first ring gear is omitted. Furthermore, the second gear ratio is preferably a second planetary gear set, which is also referred to as a second planetary transmission. The second planetary gear set has at least one or exactly one second sun gear, at least one or exactly one second ring gear, and the second planet carrier.For example, the second planetary gear set has at least one second planetary gear which is rotatably held on the second planetary carrier and meshes, in particular directly, with the second ring gear and the second sun gear, wherein direct meshing of the second sun gear with the second ring gear is preferably omitted.

[0017] Furthermore, the invention provides that the second parking lock gear is arranged coaxially with the second parking lock gear, so that the parking lock gear rotation axes coincide. Preferably, the respective parking lock gear rotation axis coincides with the main rotation axis. Preferably, the respective machine rotation axis coincides with the main rotation axis.

[0018] In order to be able to implement the parking lock in a particularly cost- and space-efficient manner, it is further provided according to the invention that the electric drive system, in particular the parking lock, has precisely one coupling shaft which is rotatable about a coupling shaft axis of rotation, in particular relative to the housing. Preferably, the coupling shaft axis of rotation is spaced from the main axis of rotation, wherein the coupling shaft axis of rotation runs parallel to the main axis of rotation. The two parking lock pawls can be actuated, in particular simultaneously, via precisely one coupling shaft and can therefore be rotated, in particular simultaneously, about respective pawl axes of rotation, in particular relative to the housing. This means that by rotating the coupling shaft, the parking lock pawls can be rotated, in particular simultaneously, between the respective locking positions and the respective release positions, in particular relative to the housing.

[0019] Furthermore, the invention provides that the first parking lock pawl and the second parking lock pawl are arranged to be rotatable about a pawl rotation axis common to the parking lock pawls, such that the respective parking lock pawl is rotatable, i.e. pivotable, about the pawl rotation axis relative to the housing. Thus, the respective parking lock pawl is rotatable, i.e. pivotable, about the pawl rotation axis relative to the housing between the respective locking position and the respective release position. Preferably, the pawl rotation axis runs parallel to the respective parking lock gear rotation axis and thus parallel to the main rotation axis and is spaced from the respective parking lock gear rotation axis and thus from the main rotation axis, such that the pawl rotation axis is preferably arranged axially parallel to the main rotation axis.

[0020] The coupling shaft rotation axis preferably runs parallel to the common pawl rotation axis and is spaced from the common pawl rotation axis so that the coupling shaft rotation axis is arranged axially parallel to the pawl rotation axis.

[0021] To achieve particularly low installation space requirements, the electric drive system, in particular the parking lock, according to the invention has a first eccentric element connected to the coupling shaft and pivotable by rotating the coupling shaft, in particular about the coupling shaft axis of rotation relative to the housing. By means of this first eccentric element, the first parking lock pawl can be actuated by pivoting the first eccentric element and can thereby be rotated about the pawl axis of rotation, in particular relative to the housing. Furthermore, according to the invention, a second eccentric element is provided, which is preferably a component of the parking lock and is connected to the coupling shaft and pivotable by rotating the coupling shaft, in particular about the coupling shaft axis of rotation and relative to the housing.By pivoting the second eccentric element, the second parking lock pawl can be actuated and thus rotated about the pawl rotation axis, particularly relative to the housing. Thus, the parking lock pawls can be actuated, particularly simultaneously, via precisely one coupling shaft, thereby keeping the number of parts, installation space requirements, weight, and cost of the parking lock to a particularly low level.

[0022] The first eccentric element is advantageously connected to the coupling shaft in a virtually rotationally fixed manner. "Almost rotationally fixed" means that, according to the invention, the first eccentric element is elastically connected to the coupling shaft, so that a rotation of the coupling shaft also causes a rotation of the first eccentric element. However, if resistance acts on the first eccentric element, the rotation of the eccentric element can be delayed. The elastic mode of action described here is known to those skilled in the art in connection with the problem of tooth-on-tooth positioning in parking locks. In the same way, the second eccentric element is advantageously connected to the coupling shaft in a virtually rotationally fixed manner.

[0023] In the context of the present disclosure, the feature that two components are connected to one another in a rotationally fixed manner is to be understood as meaning that the components connected to one another in a rotationally fixed manner are arranged coaxially to one another and, in particular when the components are driven, rotate together or simultaneously about a component rotation axis common to the components at the same angular velocity, in particular relative to the housing. In other words, the feature “rotationally fixed” is to be understood as follows: Two elements are connected to one another in a rotationally fixed manner if they are arranged coaxially to one another and are connected to one another in such a way that they rotate at the same angular velocity. The feature “coaxial” is to be understood as meaning that two elements are rotatable or rotationally symmetrical about the same axis.

[0024] The feature that two components are connected or coupled to one another in a torque-transmitting manner is to be understood as meaning that the components are coupled or connected to one another in such a way that torques can be transmitted between the components, wherein, if the components are connected or coupled to one another in a rotationally fixed manner, the components are also connected or coupled to one another in a torque-transmitting manner.

[0025] The feature that two components are permanently connected or coupled to one another in a torque-transmitting manner does not mean that a switching element is provided that can be switched between a coupling state that connects or couples the components to one another 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, i.e., connected or coupled to one another in such a way that torque can be transmitted between the components. Thus, for example, one of the components can be driven by the other component, or vice versa.

[0026] In particular, the feature that two components are permanently connected or coupled to one another in a rotationally fixed manner is to be understood as meaning that a switching element is not provided which can be switched between a coupling state which connects or couples the components to one another in a rotationally fixed manner and a decoupling state in which the components are decoupled from one another and can be rotated relative to one another so that no torque can be transmitted between the components via the switching element, but rather the components are always or always, therefore permanently, connected or coupled to one another in a rotationally fixed manner.

[0027] Furthermore, the feature that two components can be connected or coupled to one another in a rotationally fixed manner is understood to mean, for example, that the components are assigned a switching element that can be switched between at least one coupling state and at least one decoupling state. In the coupling state, the components are connected or coupled to one another in a rotationally fixed manner by means of the switching element. In the decoupling state, the components are decoupled from one another, so that in the decoupling state, the components can be rotated relative to one another, in particular about the component rotation axis.

[0028] The same applies to the feature that two components can be connected or coupled to one another in a torque-transmitting manner. Thus, for example, the feature that two components can be connected or coupled to one another in a torque-transmitting manner is to be understood as meaning that the components are assigned a switching element which can be switched between at least one connected state and at least one released state. In the connected state, the components are coupled or connected to one another in a torque-transmitting manner by means of the switching element, so that torques can be transmitted between the components, in particular via the switching element. In the released state, the components are decoupled from one another, so that in the released state, no torques can be transmitted between the components via the switching element.

[0029] A further embodiment is characterized by an actuator, also referred to as an actuator, which is designed to drive the coupling shaft and thereby rotate it about the coupling shaft's axis of rotation, in particular relative to the housing. Thus, the parking lock pawls can be rotated via the coupling shaft by means of the actuator, in particular simultaneously. Thus, the actuator is also referred to as a central actuator or central actuator. In other words, the parking lock pawls can be actuated and rotated via the coupling shaft by means of the same, single actuator, thereby keeping the number of parts and thus the costs, space requirements, and weight of the parking lock to a particularly low level.

[0030] It has proven particularly advantageous if the actuator comprises a third eccentric element which is connected, in particular permanently, in a rotationally fixed manner to the coupling shaft. The actuator is thus connected to the coupling shaft via the third eccentric element in a torque-transmitting manner, such that by rotating the third eccentric element about the coupling shaft axis of rotation and in particular relative to the housing, the coupling shaft can be rotated about the coupling shaft axis of rotation, in particular relative to the housing. In particular, the respective eccentric element is to be understood as follows: The respective eccentric element has, for example, at least one respective first surface region which has a respective first distance from the coupling shaft axis of rotation running perpendicular to the coupling shaft axis of rotation.Furthermore, for example, the respective eccentric element has at least one respective second surface region, which has a respective second distance from the coupling shaft axis of rotation, running perpendicular to the coupling shaft axis of rotation, wherein the second distance is greater than the first distance. The respective surface region can be flat, thus running in a plane which runs, for example, parallel to the coupling shaft axis of rotation, or the respective surface region can be curved, thus running curved and, for example, running along an imaginary cylindrical outer surface which runs along a radius corresponding to the respective distance. By using the eccentric elements, the parking lock pawls can be actuated and thus rotated in a particularly space-efficient manner.

[0031] In order to be able to keep the installation space requirement of the parking lock to a particularly small extent, it is provided in a further embodiment of the invention that, viewed in the axial direction of the coupling shaft and thus along the coupling shaft axis of rotation, the first parking lock gear, the first rotor, the third eccentric element, the second rotor and the second parking lock gear are arranged in the stated order, i.e. in the order in which they are named, so that, preferably viewed in the axial direction of the coupling shaft and thus along the coupling shaft axis of rotation, the first parking lock gear, the first rotor, the third eccentric element, the second rotor, the third eccentric element, the second rotor and the second parking lock gear are arranged one after the other, i.e. consecutively, in the following order: the first parking lock gear - the first rotor - the third eccentric element - the second rotor - the second parking lock gear.In other words, it is thus provided that, viewed in the axial direction of the coupling shaft and thus along the coupling shaft rotation axis, the first rotor follows the first parking lock gear, the third eccentric element follows the first rotor, the second rotor follows the third eccentric element and the second parking lock gear follows the second rotor.

[0032] In order to be able to actuate the parking lock pawls in a particularly space-efficient manner and thus achieve a particularly small installation space requirement for the parking lock, a further embodiment of the invention provides for the actuator to have a push rod that can be displaced relative to the coupling shaft and also relative to the housing along a sliding axis running perpendicular to the coupling shaft rotation axis. By displacing the push rod, the third eccentric element can be pivoted, in particular about the coupling shaft rotation axis and relative to the housing, whereby the coupling shaft can be rotated about the coupling shaft rotation axis, in particular relative to the housing.

[0033] Preferably, the push rod is coupled to the third eccentric element so as to be rotatable about a coupling axis relative to the third eccentric element, wherein the coupling axis very preferably runs parallel to the coupling shaft axis of rotation and is spaced from the coupling shaft axis of rotation. Preferably, the coupling axis runs parallel to the main axis of rotation and parallel to the pawl axis of rotation and is spaced from the main axis of rotation and the pawl axis of rotation. Thus, by moving the push rod, the third eccentric element and the coupling shaft axis of rotation can be rotated relative to the housing, whereby the coupling shaft can be rotated about the coupling shaft axis of rotation relative to the housing and as a result the parking lock pawls can be actuated, in particular simultaneously. The parking lock can thus be implemented in a particularly space-efficient manner.

[0034] In order to be able to keep the installation space requirement of the parking lock particularly low, it is provided in a further embodiment of the invention that the actuator is coupled to the coupling shaft in the axial direction of the coupling shaft between the first eccentric element and the second eccentric element, in particular in such a way that the actuator is coupled to the coupling shaft in the middle between the first eccentric element and the second eccentric element, viewed in the axial direction of the coupling shaft.

[0035] Finally, in order to achieve particularly low installation space requirements, it has proven particularly advantageous if the third eccentric element is connected to the coupling shaft in a rotationally fixed manner between the first eccentric element and the second eccentric element in the axial direction of the coupling shaft, whereby the actuator is coupled to the coupling shaft between the first eccentric element and the second eccentric element in the axial direction of the coupling shaft. Preferably, the third eccentric element is connected to the coupling shaft in a rotationally fixed manner in the middle between the first eccentric element and the second eccentric element, whereby the actuator is coupled to the coupling shaft in the middle between the first eccentric element and the second eccentric element in the axial direction of the coupling shaft.This means that the installation space requirement can be kept to a minimum and the parking lock can be particularly robust.

[0036] A second aspect of the invention relates to a motor vehicle, also simply referred to as a vehicle, and preferably designed as a motor vehicle, in particular as a passenger car, which has at least or precisely one electric drive system according to the first aspect of the invention and can be driven, in particular purely electrically, by means of the electric drive system. 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. The actuator is preferably electromechanically or hydraulically operable and is thus an electromechanical or hydraulic actuator.

[0037] The central actuator can, for example, be or comprise a gear pair with a stepper motor. Alternatively or additionally, the central actuator can, for example, be or comprise a translational adjustment mechanism, which, for example, has the push rod. For example, the actuator, in particular the adjustment mechanism, comprises a particularly hydraulic, i.e., hydraulically actuated piston-cylinder unit, by means of which, for example, the push rod can be displaced.

[0038] Preferably, the respective electrical machine is designed as an axial flux machine.

[0039] Further advantages, features, and details of the invention will become apparent from the following description of preferred embodiments and from the drawings. The features and combinations of features mentioned above in the description, as well as 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 respective specified combinations, but also in other combinations or on their own, without departing from the scope of the invention.

[0040] The drawing shows: Fig. 1 is a schematic representation of a first embodiment of an electric drive system for a motor vehicle; Fig. 2 a schematic side view of a parking lock of the electric drive system; and Fig. 3 a schematic representation of a second embodiment of the drive system.

[0041] In the figures, identical or functionally identical elements are provided with the same reference symbols.

[0042] Fig. Figure 1 shows a schematic representation of a first embodiment of an electric drive system 10 for a motor vehicle, also referred to simply as a vehicle, and preferably designed as a motor vehicle, in particular as a passenger car. This means that the motor vehicle can be driven by means of the electric drive system 10, in particular purely electrically. In its fully manufactured state, the motor vehicle has at least or exactly two vehicle axles arranged consecutively in the longitudinal direction of the motor vehicle, of which Fig. 1, a vehicle axle designated 12 can be seen. The vehicle axle 12 has at least or exactly two vehicle wheels, namely a first vehicle wheel 14 and a second vehicle wheel 16, wherein the vehicle wheels 14 and 16 are arranged on opposite sides of the motor vehicle in the transverse direction of the motor vehicle. The vehicle wheels 14 and 16 are components of the drive system 10. The drive system 10 has a first electric machine 18 with a first rotor 20 and a first stator 22, by means of which the first rotor 20 can be driven and is thus rotatable about a main axis of rotation 24 of the drive system 10 relative to the stator 22. The drive system 10 also has a second electric machine 26 with a second rotor 28 and a second stator 30, by means of which the rotor 28 can be driven and is thus rotatable about the main axis of rotation 24 relative to the stator 30. The electrical machines 18 and 26 are in the Fig. 1 are designed as axial flow machines. The drive system 10 also has a Fig. 1 particularly schematically illustrated housing 32, wherein the rotors 20 and 28 are rotatable about the main axis of rotation 24 relative to the housing 32. The drive system 10 has a first gear stage 34, which is designed to couple the first rotor 20 to the first vehicle wheel 14 in a torque-transmitting manner, such that the vehicle wheel 14 can be driven by the rotor 20 via the gear stage 34. Also provided is a second gear stage 36, which is designed to couple the second rotor 28 to the second vehicle wheel 16 in a torque-transmitting manner, such that the second vehicle wheel 16 can be driven by the second rotor 28 via the second gear stage 36. In the first embodiment, the drive system 10 is free of a coupling gear by means of which the rotors 20 and 28 are or can be coupled to one another.

[0043] The electric drive system 10 also includes a parking lock 38, which includes a first parking lock unit 40 and a second parking lock unit 42. The parking lock unit 40 includes a first parking lock gear 44, and the second parking lock unit 42 includes a second parking lock gear 46. The parking lock unit 40 includes a first parking lock pawl 48 for locking the first parking lock gear 44, and the second parking lock unit 42 includes a second parking lock pawl 50 for locking the second parking lock gear 46.

[0044] In order to realize a particularly cost- and space-efficient design of the parking lock 38, the rotors 20 and 28 are arranged coaxially with one another. Furthermore, the respective transmission stage 34, 36 is designed as a planetary gear set. The respective planetary gear set has a respective sun gear 52a, b, a respective ring gear 54a, b and a planet carrier 56a, b. The planetary gear sets are arranged coaxially with one another such that the sun gears 52a and 52b and the planet carriers 56a and 56b are rotatable about the main axis of rotation 24 relative to the housing 32. The ring gears 54a and 54b are connected, in particular permanently, in a rotationally fixed manner to the housing 32. The respective planetary gear set also has at least one respective planet gear 58a, b, which is rotatably held on the respective planet carrier 56a, b of the respective planetary gear set.The first parking lock gear 44 is, in particular permanently, connected in a rotationally fixed manner to the planet carrier 56a of the first gear stage 34, and the second parking lock gear 46 is, in particular permanently, connected in a rotationally fixed manner to the planet carrier 56b of the second gear stage 36. Furthermore, the parking lock gears 44 and 46 are arranged coaxially to one another and are thus rotatable about the main axis of rotation 24 common to the parking lock gears 44 and 46 relative to the housing 32. The parking lock pawls 48 and 50 are arranged rotatably about a pawl rotation axis 60 common to the parking lock pawls 48 and 50, such that the respective parking lock pawl 48, 50 is rotatable about the pawl rotation axis 60 relative to the housing 32. The pawl rotation axis 60 is arranged axially parallel to the main axis of rotation 24. This means that the pawl rotation axis 60 runs parallel to the main rotation axis 24 and is spaced from the main rotation axis 24.

[0045] It can be seen that the rotors 20 and 28 are arranged coaxially with one another. Furthermore, it can be seen that the first parking lock gear 44 is connected, in particular permanently, in a rotationally fixed manner to the planet carrier 56a, while the second parking lock gear 46 is connected, in particular permanently, in a rotationally fixed manner to the second planet carrier 56b. Furthermore, the parking lock gears 44 and 46 are arranged coaxially with one another and are thus rotatable relative to the housing 32 about the main axis of rotation 24 common to the parking lock gears 44 and 46.

[0046] Especially good in conjunction with Fig. 2 that the parking lock 38 has a coupling shaft 62, which is rotatable about a coupling shaft rotation axis 64 relative to the housing 32. The coupling shaft rotation axis 64 runs parallel to the pawl rotation axis 60 and parallel to the main rotation axis 24 and is spaced apart from the pawl rotation axis 60 and the main rotation axis 24, so that the coupling shaft rotation axis 64 is arranged both axially parallel to the main rotation axis 24 and axially parallel to the pawl rotation axis 60. The parking lock pawls 48 and 50 can be actuated, in particular simultaneously, via the coupling shaft 62 and can thus be rotated, in particular simultaneously, about the pawl rotation axis 60 relative to the housing 32.The parking lock 38 has a first eccentric element 66 which is connected to the coupling shaft 62 in a rotationally fixed or almost rotationally fixed manner and which can be pivoted by rotating the coupling shaft 62. By means of which first eccentric element 66 the first parking lock pawl 48 can be actuated by pivoting the first eccentric element 66 and can thereby be rotated about the pawl rotation axis 60 relative to the housing 32. The parking lock 38 also has a second eccentric element 68 which is connected to the coupling shaft 62 in a rotationally fixed or almost rotationally fixed manner and can thereby be pivoted by rotating the coupling shaft 62. By means of which second eccentric element 68 the second parking lock pawl 50 can be actuated by pivoting the second eccentric element 68 and can thereby be rotated about the pawl rotation axis 60 relative to the housing 32. Furthermore, the parking lock 38 has an actuator 70, also referred to as a central actuator, central actuator or actuator, by means of which the coupling shaft 62 can be driven and is thereby rotatable about the coupling shaft rotation axis 64 relative to the housing 32.The actuator 70 has a third eccentric element 72 which is connected to the coupling shaft 62 in a rotationally fixed manner, in particular permanently rotationally fixed.

[0047] In the first embodiment, viewed in the axial direction of the coupling shaft 62 and thus along the coupling shaft rotation axis 64, the first parking lock gear 44, the first rotor 20, the third eccentric element 72, the second rotor 28, and the second parking lock gear 46 are arranged consecutively, i.e., one after the other, in the order in which they are named. In particular, viewed along the main rotation axis 24, the gear ratio stage 34, the parking lock gears 44 and 46, and the gear ratio stage 36 are arranged in the following order: the gear ratio stage 34 - the parking lock gear 44 - the parking lock gear 46 - the gear ratio stage 36. Thus, viewed along the main rotation axis 24, the parking lock gears 44 and 46 are arranged within the gear ratio stages 34 and 36, which are here designed as output gear sets.

[0048] Particularly good looking Fig. 2 that the actuator 70 has a push rod 74, which is displaceable relative to the coupling shaft 62 and relative to the housing 32 along a sliding axis running perpendicular to the coupling shaft rotation axis 64. This means that the sliding axis runs perpendicular to a first plane and the coupling shaft rotation axis 64 runs perpendicular to a second plane, wherein the first plane and the second plane run perpendicular to one another. The push rod 74 is pivotally coupled to the third eccentric element 72 about a coupling axis 76 relative to the eccentric element 72, so that the push rod 74 is articulated to the eccentric element 72. The coupling axis 76 runs parallel to the coupling shaft rotation axis 64, parallel to the pawl rotation axis 60 and parallel to the main rotation axis 24 and is spaced from the coupling shaft rotation axis 64, from the pawl rotation axis 60 and from the main rotation axis 24.The actuator 70 has an actuating unit 78, by means of which the push rod 74 can be displaced along the sliding axis relative to the coupling shaft 62 and relative to the housing 32. The third eccentric element 72 is connected in a rotationally fixed manner to the coupling shaft 62 in the axial direction of the coupling shaft 62 between the first eccentric element 66 and the second eccentric element 68, whereby the actuator 70 is coupled to the coupling shaft 62 in the axial direction of the coupling shaft 62 between the first eccentric element 66 and the second eccentric element 68.

[0049] Fig.3 shows a schematic representation of a second embodiment of the drive system 10. In the second embodiment, the parking lock gears 44 and 46 are arranged outside the gear ratios 34 and 36 when viewed along the main axis of rotation 24, so that the parking lock gears 44 and 46 and the gear ratios 34 and 36 are arranged successively in the following order when viewed along the main axis of rotation 24: the first parking lock gear 44 - the first gear ratio 34 - the second gear ratio 36 - the second parking lock gear 46.

[0050] Furthermore, the second embodiment provides a coupling gear 80, by means of which the rotors 20 and 28 can be coupled or are coupled to one another in a torque-transmitting manner. In the present case, the rotors 20 and 28 are permanently coupled to one another in a torque-transmitting manner by means of the coupling gear 80. The coupling gear 80, also referred to as a superposition gear or designed as a superposition gear, has at least or exactly two planetary gear sets, namely a third planetary gear set 82 and a fourth planetary gear set 84. The planetary gear sets 82 and 84 have ring gears 86 and 88, sun gears 90 and 92, and planet carriers 94 and 96, wherein, for example, the planet carriers 94 and 96 are connected to one another in a rotationally fixed manner, in particular permanently. Thus, for example, the planet carriers 94 and 96 are formed by a common overall planet carrier.For example, the planet carriers 94 and 96 and the ring gears 86 and 88 perform a differential gear function, so that, for example, the coupling gear 80 is designed and / or operable as a differential gear. It can be seen that the rotor 20 is connected, in particular permanently, in a rotationally fixed manner to the sun gear 92, and the rotor 28 is connected, in particular permanently, in a rotationally fixed manner to the sun gear 90, so that the rotors 20 and 28 are connected to the sun gears 90 and 92. This results in, in particular in addition to the differential gear function, a superposition function, by means of which a respective first drive torque provided or capable of being provided by the electric machine 18 via its rotor 20 can be superimposed on a respective second drive torque provided or capable of being provided by the second electric machine 26 via its rotor 28.

[0051] For example, the coupling shaft 62 is designed to be torsionally flexible. Alternatively or additionally, the eccentric element 66 and / or the eccentric element 68 and / or the eccentric element 72 are particularly advantageously torsionally flexible, particularly with respect to the coupling shaft rotation axis 64, and thus are each connected to the coupling shaft 62 in a virtually rotationally fixed manner. If, for example, during an insertion process intended for engaging the respective parking lock unit 40, 42, a tooth-on-tooth position of the respective parking lock pawl 48, 50 with the respective corresponding parking lock gear 44, 46 occurs, the coupling shaft 62 can be twisted about the coupling shaft rotation axis 64 by the torsionally elastic connection and / or the torsionally elastic design of the coupling shaft 62, in that the eccentric element 72 is rotated about the coupling shaft rotation axis 64 relative to the housing 32, in particular by means of the push rod 74.If, for example, the tooth-on-tooth position is then released, for example by the respective vehicle wheel 14, 16 rotating a small distance, the twisted coupling shaft 62 can at least partially relax, whereby the respective eccentric element 66, 68 is rotated about the coupling shaft rotation axis 64 relative to the housing 32 and thereby the respective parking lock pawl 48, 50 can be rotated into engagement with the respective corresponding parking lock wheel 44, 46, whereby the respective parking lock unit 40, 42 is engaged. List of reference symbols 10 electric drive system 12 vehicle axles 14 first vehicle wheel 16 second vehicle wheel 18 first electric machine 20 first rotor 22 first stator 24 Main axis of rotation 26 second electric machine 28 second rotor 30 second stator 32 housings 34 first translation level 36 second gear ratio 38 Parking lock 40 first parking lock unit 42 second parking lock unit 44 first parking lock gear 46 second parking lock gear 48 first parking lock pawl 50 second parking lock pawl 52a, b sun gear 54a, b ring gear 56a, b planet carrier 58a, b planetary gear 60 pawl rotation axis 62 coupling shaft 64 Coupling shaft rotation axis 66 first eccentric element 68 second eccentric element 70 Actuator 72 third eccentric element 74 push rod 76 coupling axle 78 Actuating unit 80 coupling gears 82 third planetary gear set 84 fourth planetary gear set 86 ring gear 88 ring gear 90 Sun gear 92 Sun gear 94 planet carrier 96 planet carriers

Claims

[1] An electric drive system (10) for a motor vehicle, comprising a first electric machine (18) having a first rotor (20), a second electric machine (26) having a second rotor (28), a first vehicle wheel (14), a second vehicle wheel (16), a first gear stage (34) designed to couple the first rotor (20) to the first vehicle wheel (14) in a torque-transmitting manner, a second gear stage (36) designed to couple the second rotor (28) to the second vehicle wheel (16) in a torque-transmitting manner, a first parking lock gear (44), a second parking lock gear (46), a first parking lock pawl (48) for locking the first parking lock gear (44), and a second parking lock pawl (50) for locking the second parking lock gear (46), characterized by , that: - the first rotor (20) is arranged coaxially to the second rotor (28), - the first parking lock gear (44) is coupled to a first planet carrier (56a) of the first gear ratio (34) in a torque-transmitting manner, - the second parking lock gear (46) is coupled to a second planet carrier (56b) of the second gear stage (36) in a torque-transmitting manner and is arranged coaxially to the first parking lock gear (44), wherein exactly one coupling shaft (62) is provided which is rotatable about a coupling shaft rotation axis (64) and via which the two parking lock pawls (48, 50) can be actuated, wherein the first parking lock pawl (48) and the second parking lock pawl (50) are arranged to be rotatable about a common pawl rotation axis (60), where - a first eccentric element (66) is elastically connected to the coupling shaft (62) and pivotable by rotating the coupling shaft (62), by means of which the first parking lock pawl (48) can be actuated by pivoting the first eccentric element (66) and can thereby be rotated about the pawl rotation axis (60), wherein, if a resistance acts on the first eccentric element (66), the rotation of the first eccentric element (66) can be delayed relative to the coupling shaft (62); and - a second eccentric element (68) is elastically connected to the coupling shaft (62) and pivotable by rotating the coupling shaft (62), by means of which the second parking lock pawl (50) can be actuated by pivoting the second eccentric element (68) and can thereby be rotated about the pawl rotation axis (60), wherein, if a resistance acts on the second eccentric element (68), the rotation of the second eccentric element (68) can be delayed relative to the coupling shaft (62). [2] Electric drive system (10) according to claim 1, characterized by an actuator (70) which is designed to rotate the coupling shaft (62) about the coupling shaft rotation axis (64). [3] Electric drive system (10) according to claim 2, characterized by that the actuator (70) comprises a third eccentric element (72) which is connected in a rotationally fixed manner to the coupling shaft (62). [4] Electric drive system (10) according to claim 3, characterized by in that in the axial direction of the coupling shaft (62) the first parking lock gear (44), the first rotor (20), the third eccentric element (72), the second rotor (28) and the second parking lock gear (46) are arranged one after the other in the following order: the first parking lock gear (44) - the first rotor (20) - the third eccentric element (72) - the second rotor (28) - the second parking lock gear (46). [5] Electric drive system (10) according to claim 3 or 4, characterized byin that the actuator (70) has a push rod (74) which is displaceable relative to the coupling shaft (62) along a sliding axis running perpendicular to the coupling shaft rotation axis (64), by means of which the third eccentric element (72) can be pivoted by displacing the push rod (74), whereby the coupling shaft (62) can be rotated about the coupling shaft rotation axis (64). [6] Electric drive system (10) according to one of claims 2 to 5, characterized by that the actuator (70) is coupled to the coupling shaft (62) in the axial direction of the coupling shaft (62) between the first eccentric element (66) and the second eccentric element (68). [7] Electric drive system (10) according to claim 6 in its dependence on one of claims 3 to 5, characterized bythat the third eccentric element (72) is connected in a rotationally fixed manner to the coupling shaft (62) in the axial direction of the coupling shaft (62) between the first eccentric element (66) and the second eccentric element (68), whereby the actuator (70) is coupled to the coupling shaft (62) in the axial direction of the coupling shaft (62) between the first eccentric element (66) and the second eccentric element (68). [8] Motor vehicle, comprising an electric drive system (10) according to one of the preceding claims.

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