Electric drive system for a motor vehicle and motor vehicles

Abstract

Electric drive system (10) for a motor vehicle, comprising: an electric machine (16) comprising a stator (18) and a rotor (20); a planetary gear set (28) comprising: a first planetary gear set (30) comprising a first sun gear (34), a first planet carrier (36) and a first ring gear (38); and a second planetary gear set (32) comprising a second sun gear (40), a second planet carrier (42) and a second ring gear (44) and arranged radially outside and axially overlapping the first planetary gear set (30) with respect to an axis of rotation (45) of the planetary gear set (28); a first brake switching element (SE1) configured to connect the first ring gear (38) to the housing wall (68) in a rotationally fixed manner, wherein a housing-side switching half (70) of the first brake switching element (SE1) is arranged on the housing wall (68);- a differential gear (46), characterized in that the differential gear has a first crown gear (48), a second crown gear (50) and compensating gears (56) arranged axially between the crown gears (48, 50) and meshing with them, each of which is arranged on a respective bearing pin (66) which is rotationally fixed to the first planet carrier (36) and rotationally fixed to the second ring gear (44), wherein a housing wall (68) extending radially is arranged axially adjacent to the planet gear (28);wherein, with respect to the axis of rotation (45) of the planetary gear (28), the rotor (20), the housing wall (68), the planetary gear (28), the first crown gear (48) and the second crown gear (50) are arranged successively in the following sequence: the rotor (20) - the housing wall (68) - the planetary gear (28) - the first crown gear (48) - the second crown gear (50), wherein a one-piece support element (74) is provided which comprises a plate section (76), a first cylinder section (78) and a second cylinder section (80), wherein planet gear pins (84) for first planet gears (P1) of the planetary gear (28) are arranged on the plate section (76), wherein the second ring gear (44) is arranged on a radial inner surface (S1) of the first cylinder section (78), and wherein the bearing pins (66) are arranged on a radial inner surface (S2) of the second cylinder section (80) Compensating bolts for the compensating gears (56) are arranged.;

Description

The invention relates to an electric drive system for a motor vehicle. Furthermore, the invention relates to a motor vehicle with at least one such electric drive system. DE 10 2018 008 939 B3 discloses an electric drive device for a motor vehicle. Furthermore, DE 10 2014 000 499 A1 discloses a differential gear for a motor vehicle, wherein an output gear can be designed as a crown gear. DE 11 2004 002 526 B4 also discloses a crown gear differential. DE 10 2017 006 266 A1 discloses an electric drive device with two planetary gear sets that are radially nested. DE 10 2021 103 176 A1 discloses an electric drive device with an electric machine designed as an axial flux machine. The object of the present invention is to create an electric drive system for a motor vehicle and a motor vehicle with such an electric drive system, so that a particularly compact design can be achieved. This problem is solved by an electric drive system with the features of claim 1 and by a motor vehicle with the features of claim 5. Advantageous embodiments with expedient further developments of the invention are specified in the remaining claims. A first aspect of the invention relates to an electric drive system for a motor vehicle, also referred to as an electric drive device or designed as such. 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, in particular purely electrically, by means of the electric drive system. For example, the motor vehicle, in its fully manufactured state, has at least or exactly two axles, also referred to simply as axles, arranged consecutively and thus one behind the other in the longitudinal direction of the motor vehicle. Each axle has, for example, at least or exactly two wheels, also referred to simply as wheels.The wheels of each vehicle axle are arranged, for example, on opposite sides of the vehicle in the transverse direction. The wheels are ground contact elements that allow the vehicle to be supported or stabilized against the ground in its vertical direction. For example, the vehicle is a motor vehicle, particularly a passenger car. When the vehicle is driven along the ground while supported by the ground contact elements, the wheels roll along the ground. The electric drive system can, for example, drive at least one or exactly one of the axles, or both axles, electrically.The vehicle wheels driven by the electric drive system are also called drive wheels. When the term "vehicle wheels" is used below, it refers to the drive wheels unless otherwise specified. The electric drive system comprises an electric machine, which has a stator and a rotor. For example, the stator can be driven by the rotor and thus rotated around a machine axis relative to the rotor. In particular, the electric machine can provide drive torques via its rotor, which can be used to electrically drive the vehicle, especially its wheels. The electric drive system also includes a planetary gear set. For example, the electric drive system comprises a housing, in which the planetary gear set may be at least partially located. The planetary gear set includes a first planet gear set, also referred to as the first planetary gear set. The first planet gear set includes a first sun gear, a first planet carrier, and a first ring gear. The first sun gear, the first planet carrier, and the first ring gear are the first gear elements of the planet gear set. Particularly if the respective first gear element is not rotationally fixed to the housing, it can be rotated about a first planet gear set axis of rotation relative to the housing. The planetary gear set also includes a second planetary gear set, also referred to as the second planetary gear set. This second planetary gear set comprises a second sun gear, a second planet carrier, and a second ring gear. The second sun gear, the second planet carrier, and the second ring gear are the second gear elements of the second planetary gear set. Particularly when the respective second gear element is not fixed to the housing, it can rotate about a second planetary gear set axis of rotation relative to the housing. Specifically, the planetary gear sets are arranged coaxially with respect to each other, particularly with respect to their planetary gear set axes of rotation, so that the planetary gear set axes of rotation coincide. The planetary gear set axes of rotation thus run along or form a common axis of rotation. In other words, the respective planetary gear set axis of rotation is also referred to as the axis of rotation. The second planetary gear set is arranged radially outside the axis of rotation of the planetary gear set and axially overlapping with the first planetary gear set. Unless otherwise specified, the terms "axial" and "radial" in this disclosure refer to the axis of rotation of the planetary gear set, to which the first gear elements and, for example, also the second gear elements are arranged coaxially. "Radial within" means, in particular, the following: An element, especially one rotatably mounted, such as the first planetary gear set, is arranged radially within another element, especially one rotatably mounted, such as the first planetary gear set, when it is arranged in a region of smaller radii, particularly in the radial direction of the planetary gear set and thus of the electric drive system, the radial direction of which is perpendicular to the axial direction of the planetary gear set and thus of the electric drive system. The axial direction coincides with the axis of rotation."Radially outside" therefore means that an element, in particular one rotatably mounted, is arranged radially outside another element, in particular one rotatably mounted, when it is arranged in an area of ​​larger radii. In particular, "axially overlapping" means the following: Two elements, such as planetary gear sets, are arranged axially overlapping, especially relative to each other, when viewed along the axis of rotation and thus in the axial direction of the planetary gear set and the drive system, if they are arranged at least partially in the same axial area. In other words, two elements are arranged axially overlapping, especially relative to each other, if these two elements have at least partially the same coordinates with respect to a reference axis, which is the axis of rotation. "Coaxial" means that two elements, especially those rotatably mounted, are arranged coaxially relative to each other if they are rotatably mounted about the same axis of rotation. The electric drive system includes a differential gear, also referred to as a differential, axle differential, or axle transmission, which is provided in addition to the planetary gear set. For example, the vehicle wheels can be driven by the electric motor, particularly the rotor, via the differential gear. Specifically, the differential gear can be driven by the rotor, and thus the electric motor, via the planetary gear set.Thus, it is specifically provided that, with regard to a torque flow along which the respective drive torque provided or available by the rotor can be transmitted from the rotor to the respective vehicle wheel, the planetary gear and differential gear are arranged in the torque flow such that the planetary gear is arranged downstream of the rotor and upstream of the differential gear, and the differential gear is arranged downstream of the planetary gear and upstream of the respective vehicle wheel. Advantageously, the differential gear is arranged coaxially with the planetary gear. It is also advantageous for the rotor, the differential gear, and the planetary gear to all be arranged coaxially with each other. According to the invention, the differential gear comprises a first crown gear, in particular as the first output gear, and a second crown gear, in particular as the second output gear. The respective drive torque, which is also referred to as drive torque, can, for example, be introduced from the rotor into the planetary gear. The planetary gear can, for example, provide a respective input torque resulting from the respective drive torque introduced into the planetary gear, which can be introduced into the differential gear. The differential gear can, for example, distribute the respective input torque introduced into the differential gear, in particular half, to the vehicle wheels, in particular to the crown gears, so that, for example, the respective crown gear can provide a respective output torque resulting from the respective input torque.The respective vehicle wheel can be driven by means of the respective output torque provided. According to the invention, the differential gear includes compensating gears. The crown gears and the compensating gears are designed as toothed gears. The compensating gears are arranged axially, that is, in the axial direction of the electrical drive system and thus along the axis of rotation, between the crown gears, with the compensating gears meshing with the respective crown gears, in particular simultaneously. For example, a first crown gear has a first tooth on its first axial end face, and for example, the second crown gear has a second tooth on its second axial end face. For example, the first axial end face faces the second axial end face in the axial direction of the electrical drive system, and vice versa, so that the axial end faces and thus the toothing faces each other in the axial direction of the drive system.The compensating gears engage with the teeth of the crown gears, so that the compensating gears mesh with the crown gears. In particular, the compensating gears are arranged in the axial direction of the drive system between the axial end faces. The respective differential gear is arranged on a respective bearing pin, in particular rotatably, and, for example, the respective differential gear is rotatably mounted on the respective associated bearing pin. The respective bearing pin is, in particular, permanently and non-rotatably connected to the first planet carrier and to the second ring gear, such that, for example, the first planet carrier and the second ring gear are, in particular, permanently and non-rotatably connected to each other. The respective bearing pin of the respective differential gear defines a respective differential gear axis of rotation about which the respective differential gear is rotatably mounted on the respective bearing pin of the differential gear. The respective differential gear axis of rotation is arranged perpendicular to the axis of rotation of the planetary gear set. The respective differential gear axis of rotation is also arranged perpendicular to the planet gear pins (more precisely: to axes of rotation defined by the planet gear pins).Planetary gear bolts serve to support the planet gears of the planetary gear system. More precisely, the axes of rotation defined by the planetary gear bolts are arranged parallel to the axis of rotation of the planetary gear system. A housing wall is arranged axially adjacent to the planetary gear unit. For example, the housing wall is arranged in the axial direction of the drive system between the electric motor and the planetary gear unit. It is also conceivable that the differential gear unit and the planetary gear unit are arranged on a first side of the housing wall, with the electric motor, for example, arranged on a second side of the housing wall. The first housing wall faces away from the second housing wall in the axial direction of the electric motor, and vice versa. In particular, the housing wall is also referred to as a wall of the aforementioned housing. The electric drive system also includes a brake switching element, which is also referred to as the first switching element. The brake switching element is designed to connect the first ring gear to the housing wall in a rotationally fixed manner, and thus to the housing itself. A housing-side switching half of the brake switching element is arranged on the housing wall, in particular such that this half is permanently connected to the housing wall in a rotationally fixed manner. In other words, the brake switching element allows the first ring gear to be connected to the housing wall in a rotationally fixed manner. For example, the brake switching element can be switched between a first coupling state and a first end coupling state. In the first coupling state, the brake switching element connects the first ring gear to the housing wall in a rotationally fixed manner.In the first end-coupling state, the brake switching element releases the first ring gear for rotation about the axis of rotation and relative to the housing wall. For example, the brake switching element can be moved, particularly relative to the housing or the housing wall and / or translationally, between at least one first coupling position that effects the first coupling state and at least one first end-coupling position that effects the first end-coupling state. This means, in particular, that at least one switching element of the brake switching element is movable between the first end-coupling position and the first coupling position. The switching element is, or comprises, for example, friction plates. In particular, it is conceivable that the brake switching element is a multi-plate clutch, also referred to as a friction clutch, or designed as a friction clutch, whose plate carrier is, for example, arranged coaxially to the planetary gear sets. Since the second planetary gear set is arranged radially outside and axially overlapping the first planetary gear set, the planetary gear sets are stacked at least partially, and in particular at least predominantly and thus to more than half or even completely, with respect to the axis of rotation, and in particular stacked with overlapping edges, which allows for a particularly compact design, especially in the axial direction of the drive system. The first crown gear and the second crown gear are gears which are designed in particular as output gears. Since the output gears are crown gears, the differential is designed as a crown gear differential, which allows for a particularly compact design. Since the housing-side switching half of the brake switching element is arranged on the housing wall, the housing-side switching half is connected to the housing wall, which is also referred to as or designed as an intermediate wall.This allows for particularly favorable noise characteristics, also known as NVH (Noise, Vibration, Harshness). Furthermore, the brake switching element enables particularly demand-oriented and advantageous switching of the drive system. Within the context of the present disclosure, ordinal numbers such as "first", "second", and "second" etc., which are referred to as ordinalia, are not necessarily used to indicate or imply a number or quantity, but rather to be able to clearly refer to terms to which the ordinal numbers are assigned or to which the ordinal numbers refer. Within the scope of this disclosure, the feature that two components are rotationally fixed to one another is understood to mean that the components connected 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 common axis of rotation of the components, such as the aforementioned axis of rotation, at the same angular velocity, especially relative to the housing. The feature that two components are connected to one another in a torque-transmitting manner is understood to mean that the components are coupled to one another in such a way that torques can be transmitted between the components, wherein, if the components are connected in a rotationally fixed manner, the components are also connected to one another in a torque-transmitting manner. The characteristic that two components are permanently connected in a torque-transmitting manner means that there is no switching element that can be toggled between a coupling state connecting the components in a torque-transmitting manner and a final coupling 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 coupled to each other in such a way that torque can be transmitted between them. Thus, for example, one component can be driven by the other, and vice versa.In particular, the characteristic that two components are connected to each other in a rotationally fixed manner means that a switching element is not provided which can be switched between a coupling state that connects the components in a rotationally fixed manner and an end-coupling state in which the components are decoupled from each other and rotatable relative to each other, so that no torques can be transmitted between the components via the switching element, but rather the components are always, or always, permanently connected or coupled to each other in a rotationally fixed manner. The characteristic that two components can be connected to each other in a rotationally fixed or torque-transmitting manner means, in particular, that the components are assigned a switching element which can be switched between at least one coupling state and at least one end-coupling state. In the coupling state, the components are connected to each other in a rotationally fixed or torque-transmitting manner by means of the switching element, such as a brake switching element. In the end-coupling state, the components are decoupled from each other, so that in the end-coupling state the components can rotate relative to each other, in particular about the component axis of rotation, and in particular so that no torques can be transmitted between the components via the switching element. Thus, "rotatably connected" means that two elements, of which at least one or both are rotatably mounted, are rotatably connected to each other if they are arranged coaxially and connected in such a way that they rotate at the same angular velocity. The characteristic that an element is formed in one piece means that the element is formed in a single component. The element therefore has no joint, such as a joining point. In other words, the one-piece element is manufactured, for example, by primary forming, such as casting or forging, so that the one-piece element is, for example, a casting or forging.In other words, the one-piece element is not composed of several parts formed separately from each other and connected to each other, but rather the one-piece element is formed from a single piece, so that the one-piece element is formed by a monoblock or is designed as a monoblock. In order to keep the installation space requirement of the electric drive system, particularly in the axial direction of the electric drive system and thus along the axis of rotation, within a particularly small range, it is further provided according to the invention that, with regard to the axis of rotation of the planetary gear, i.e., along the axis of rotation of the planetary gear, the rotor, the housing wall, the planetary gear, the first crown gear and the second crown gear are arranged in the aforementioned order, i.e., in the order in which they are mentioned, one after the other, i.e., consecutively.In other words, it is preferably provided that, along the axis of rotation of the planetary gear unit and thus in the axial direction of the drive system, the rotor, the housing wall, the planetary gear unit, the first crown gear, and the second crown gear are arranged successively in the following order: the rotor – the housing wall – the planetary gear unit – the first crown gear – the second crown gear. Put another way, in the axial direction of the drive system, the housing wall adjoins the rotor, the planetary gear unit adjoins the housing wall in the axial direction, the first crown gear unit adjoins the planetary gear unit in the axial direction, and the second crown gear unit adjoins the first crown gear unit in the axial direction. Furthermore, according to the invention, a one-piece, i.e., integrally formed, support element is provided.The support element according to the invention comprises a plate section, a first cylinder section, and a second cylinder section. Each cylinder section is, for example, cylindrical on its inner and / or outer circumference, i.e., in the form of a straight circular cylinder, particularly a hollow cylinder. The plate section, the first cylinder section, and the second cylinder section are arranged coaxially with each other. Planet gear pins for first planet gears of the planetary gear set are arranged on the plate section. In particular, each planet gear pin is fixed to the plate section in a rotationally fixed manner. For example, each of the first planet gears is rotatably mounted on each planet gear pin.The first planet gears are, for example, part of the first planet gear set, wherein, for example, the respective first planet gear meshes, in particular simultaneously, with the first sun gear and the first ring gear. For example, the second ring gear is arranged on a radial inner surface of the first cylinder section, i.e., an inner surface facing radially inwards in the drive system, in particular such that the second ring gear is permanently and rotationally fixed to the radial inner surface of the first cylinder section. The radial inner surface of the third cylinder section is also referred to as the first radial inner surface. Furthermore, it is preferably provided that compensating bolts for the compensating gears are arranged on a radial inner surface of the second cylinder section, also referred to as the second radial inner surface.In this arrangement, for example, each of the compensating gears is held, in particular rotatably, or mounted on the respective compensating bolt. For example, the respective compensating bolt is fixed to the second radial inner surface of the second cylinder section. The one-piece support element is thus, for example, a component of the first planet carrier. By using the partial support element, a particularly compact and lightweight design can be achieved. Another embodiment is characterized by a further brake switching element, which is also referred to as a second switching element. It is conceivable that the first brake switching element is designed as a friction brake. For example, the further brake switching element is designed as a positive-locking switching element, i.e., for example, as a jaw coupling. The further brake switching element is designed to connect the second planetary carrier to the housing in a rotationally fixed manner. In other words, the second planetary carrier can be connected to the housing in a rotationally fixed manner by means of the further switching element. For example, the further brake switching element can be switched between a second coupled state and a second end-disengagement state. In the second coupled state, the second planetary carrier is connected to the housing in a rotationally fixed manner by means of the second switching element (further brake switching element).In the second end-coupling state, the additional brake switching element releases the second planet carrier for rotation about the axis of rotation and relative to the housing. For example, the additional brake switching element, that is, at least a further switching part of the additional brake switching element, can be moved, particularly relative to the housing and / or translationally, between at least one second coupling position that effects the second coupling state and at least one second end-coupling position that effects the second end-coupling state. This allows for advantageous switching of the drive system in a space-saving manner. Finally, it has proven particularly advantageous for realizing a particularly weight- and space-saving design of the drive system if the electric machine is designed as an axial flux machine. For example, the one-piece support element is made of a light metal, in particular aluminum. Most preferably, the support element is designed as an aluminum casting. The respective planetary gear bolt is, for example, formed in one piece. The respective planetary gear bolt can, for example, be made of a metallic material, particularly steel, so that the respective planetary gear bolt is, for example, a steel bolt. Furthermore, it is conceivable that the respective compensating bolt is formed in one piece. In particular, it is conceivable that the respective compensating bolt is made of a metallic material, especially steel, so that the respective compensating bolt can be a steel bolt. A second aspect of the invention relates to a motor vehicle, preferably designed as a motor vehicle, in particular as a passenger car, and also referred to as a vehicle, which has an electric drive system according to the first aspect of the invention and can be driven electrically, in particular purely, 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. 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 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. The drawing shows in: Fig. 1 a schematic representation of a first embodiment of an electric drive system for a motor vehicle: and Fig. 2 a schematic representation of a second embodiment of the electric drive system. In the figures, identical or functionally equivalent elements are provided with the same reference symbols. Fig. 1 shows a schematic representation of a first embodiment of an electric drive system 10 for a motor vehicle. This means that the motor vehicle, also referred to simply as a vehicle, in its fully manufactured state has the drive system 10 and can be driven, in particular purely electrically, by means of the drive system 10. The motor vehicle has at least or exactly two axles arranged consecutively and thus one behind the other in the longitudinal direction of the motor vehicle. Each axle has at least or exactly two wheels, with the wheels of each axle being arranged on opposite sides in the transverse direction of the motor vehicle. The wheels of at least or exactly one of the axles can be driven electrically by means of the drive system 10. The wheels that can be driven by means of the drive system 10 are shown in Fig.1 is shown particularly schematically and labelled 12 and 14. The electric drive system 10 comprises an electric machine 16, which has a stator 18 and a rotor 20. The electric machine 16 can provide drive torques for driving the vehicle wheels 12 and 14 via its rotor 20. The respective drive torque is illustrated by an arrow 22 in Fig. 1. The rotor 20 can be driven by means of the stator 18 and is thus rotatable about a machine axis 24 relative to the stator 18 and also relative to a housing 26 of the drive system 10. The drive system 10 comprises a planetary gear set 28, which includes a first planet gear set 30 and a second planet gear set 32. The first planet gear set 30 includes a first sun gear 34, a first planet carrier 36, and a first ring gear 38. The second planet gear set 32 ​​includes a second sun gear 40, a second planet carrier 42, and a second ring gear 44. The first planet gear set 30 includes planet gears, one of which, designated P1, is visible in Fig. 1. As can be seen from the example of planet gear P1, the planet gears P1 are rotatably held on the planet carrier 36, in particular by bearings. Each planet gear P1 meshes, in particular simultaneously, with the sun gear 34 and the ring gear 38. The planet gear set 32 ​​includes second planet gears, one of which, designated P2, is shown in Fig. 1.The example of the second planet gear P2 shows that the second planet gears P2 are rotatably held, in particular mounted, on the planet carrier 42. Each planet gear P2 meshes, in particular simultaneously, with the sun gear 40 and with the ring gear 44. The second planetary gear set 32 ​​is arranged radially outside and axially overlapping the first planetary gear set 30 with respect to a rotation axis 45 of the planetary gear set 28, also referred to as the planetary gear set rotation axis, such that the planetary gear sets 30 and 32 are stacked, in particular stacked on top of each other, in the axial direction of the planetary gear set 28 and the drive system 10, which coincides with the rotation axis 45. In the first embodiment, the planetary gear sets 30 and 32 are stacked on top of each other such that the planetary gear set 32 ​​is arranged on the planetary gear set 30 or stacked on the planetary gear set 30. In other words, the planetary gear set 30, viewed in the axial direction of the drive system 10 and thus along the rotation axis 45, is arranged at least partially, in particular at least predominantly and thus at least more than half or completely, within the second planetary gear set 32.The sun gears 34 and 40, the planet carriers 36 and 42, and the ring gears 38 and 44 are gear elements of the planetary gear set 28. In particular, if the respective gear element is not rotationally fixed to the housing 26, it can rotate about the axis of rotation 45 relative to the housing 26. It can be seen that the planetary gear sets 30 and 32 are arranged coaxially with each other, and the electric machine 16 is arranged coaxially with the planetary gear sets 30 and 32, so that the machine's axis of rotation 24 coincides with the axis of rotation 45. The drive system 10 also includes a differential gear 46, which is designed as a crown gear differential. The differential gear 46 has a first crown gear 48 as the first output gear and a second crown gear 50 as the second output gear. The output gears are gears. The crown gear 48 has a first axial face 52, and the crown gear 50 has a second axial face 54. The axial faces 52 and 54 are oriented axially towards each other in the direction of the drive system 10 and thus, when viewed along the axis of rotation 45, towards each other. On or at face 52, the crown gear 48 has a first tooth, and on or at face 54, the crown gear 50 has a second tooth. Thus, the toothing faces each other in the axial direction of the drive system 10. The differential gear 46 also includes differential gears, one of which, designated 56, is visible in Fig. 1. Each differential gear 56 is a further gear of the differential gear 46. The differential gear 56 is arranged axially within the planetary gear set 28 and thus within the drive system 10, between the crown gears 48 and 50, in particular between the end faces 52 and 54. The differential gears 56 mesh with the crown gears 48 and 50, in particular simultaneously. The differential gears 56 are rotatable about a differential axis 58 relative to the housing 26. Furthermore, each differential gear 56 is rotatable about a differential axis 60, also referred to as a differential axis, relative to the housing 26, with the differential axis 60 being perpendicular to the differential axis 58.It can be seen that the differential gear 46 is arranged coaxially to the planetary gear sets 30 and 32, thus coaxially to the planetary gear 28 and also coaxially to the electric machine 16, so that the differential rotation axis 58 coincides with a machine rotation axis 24 with the rotation axis 45. The respective drive torque provided or available by arrow 22 can be introduced into the planetary gear 28. The planetary gear 28 can, in particular via the planet carrier 36, provide a respective input torque resulting from the respective drive torque, which can be introduced into the differential gear 46, in particular via the differential gears 56. The differential gear 46 can distribute or transmit the respective input torque, in particular in equal parts, to the vehicle wheels 12 and 14, in particular such that the respective crown gear 48, 50 can provide a respective output torque resulting from the respective input torque. The output torque available from the crown gear 48 is illustrated in Fig. 1 by arrow 62, and the output torque available from the crown gear 50 is illustrated by arrow 64.It can be seen that the vehicle wheel 12 can be driven by means of the output torque illustrated by arrow 62 and thus by means of the crown gear 48, and the vehicle wheel 14 can be driven by means of the output torque illustrated by arrow 64 and thus by means of the crown gear 50. The crown gears 48 and 50 are arranged coaxially with each other and are rotatable about the differential axis of rotation 58 relative to the housing 26 and, in particular, relative to each other.In particular, the differential gear 46 has the functionality already well known from the general prior art that the differential gear 46 allows different rotational speeds in the vehicle wheels 12 and 14, especially when the vehicle is cornering, in particular such that the outer vehicle wheel rotates or can rotate at a higher rotational speed than the inner vehicle wheel, especially while the vehicle wheels 12 and 14 are connected to the rotor 20 in a torque-transmitting manner and are thus driven or can be driven by the rotor 20. The respective compensating gear 56 is rotatably arranged on a respective bearing pin 66. The respective bearing pin 66 is, in particular, permanently and non-rotatably connected to the planet carrier 36 and, in particular, permanently and non-rotatably connected to the second ring gear 44. Thus, it is specifically provided that the second ring gear 44 and the first planet carrier 36 are, in particular, permanently and non-rotatably connected to each other. It can be seen that the ring gear 44 and the planet carrier 36 form an output of the planetary gear set 28, which can provide the respective input torque resulting from the respective drive torque via its output. In the first embodiment shown in Fig. 1, a housing wall 68, which is a wall of the housing 26, is arranged axially adjacent to the planetary gear 28. The housing wall 68 extends radially, i.e., with respect to the axis of rotation 45, in the radial direction of the planetary gear 28 and thus of the drive system 10, the radial direction of which is perpendicular to the aforementioned axial direction of the planetary gear 28 and thus of the drive system 10. In the first embodiment, the housing wall 68 is arranged on an axial side of the planetary gear facing away from the rotor 20. Both a first brake switching element SE1 and a second brake switching element SE2 each have a switching half directly and rotationally fixed to the housing wall 68, namely a first switching half 70 of the first brake switching element SE1 and a third switching half 71 of the second brake switching element SE2.The first brake switching element SE1 is configured to connect the second sun gear 40 and the first ring gear 38 to the housing 26 in a rotationally fixed manner. The second brake switching element is configured to connect the second planet carrier 42 to the housing 26 in a rotationally fixed manner. The first brake switching element SE1 and the second brake switching element SE2 are advantageously arranged axially overlapping each other. Advantageously, the second brake switching element SE2 is arranged axially outside the first brake switching element SE1. In the first embodiment of the electrical machine 16 shown in Fig. 1, it is designed as a radial flux machine. Fig. 2 shows a second embodiment of the drive system 10. As can be seen from Fig. 2, in the second embodiment the housing wall 68, which is a wall of the housing 26, is also arranged axially adjacent to the planetary gear 28. In the second embodiment, the drive system 10 also includes the first brake switching element SE1, by means of which the first ring gear 38 can be connected to the housing 26 and thus to the housing wall 68 in a rotationally fixed manner. The housing-side, first switching half 70 of the first brake switching element SE1 is arranged on the housing wall 68, in particular such that the first switching half 70 is permanently connected to the housing wall 68 in a rotationally fixed manner. For example, a wheel-side, second switching half 72 of the first brake switching element SE1 is arranged on the first ring gear 38, in particular permanently connected to the first ring gear 38 in a rotationally fixed manner. It can be seen that in the second embodiment, with respect to an axial direction of the axis of rotation 45 of the planetary gear 28 and thus in the axial direction of the planetary gear 28 and the drive system 10, the rotor 20, the housing wall 68, the planetary gear 28, the first crown gear 48 and the second crown gear 50 are arranged successively in the following order: the rotor 20 - the housing wall 68 - the planetary gear 28 - the first crown gear 48 - the second crown gear 50. In the second embodiment, the drive system 10 also includes the second brake switching element SE2, by means of which the second planet carrier 42 can be connected to the housing 26 in a rotationally fixed manner. In its second embodiment, the electric drive system 10 comprises a one-piece, i.e., single-unit, carrier element 74, which is, for example, a component of the planet carrier 36 or forms the planet carrier 36 itself. The carrier element 74 has a disc section 76, a first cylindrical section 78, and a second cylindrical section 80. The respective compensating gear 56 is held, in particular rotatably, on the respective bearing pin 66, also referred to as a compensating pin. The respective first planet gear P1 is held, in particular rotatably, on a respective planet gear pin 84. As can be seen from Fig. 2, the planet gear pins 84 for the first planet gears P1 are arranged, in particular rotationally fixed, on the disc section 76.For example, the planet gear pins 84 are formed separately from the support element 74 and thus from the plate section 76 and are held, in particular, rotationally fixed to the plate section 76. The second ring gear 44 is arranged, in particular, rotationally fixed, on a first radial inner surface S1 of the second cylinder section 78. It is conceivable that the ring gear 44 is formed separately from the support element 74 and thus separately from the first cylinder section 78 and is arranged, in particular, rotationally fixed, on the first radial inner surface S1 and thus on the first cylinder section 78. Furthermore, it is conceivable that the ring gear 44 is formed integrally with the support element 74, so that the one-piece support element 74 forms the second ring gear 44. The compensating pins (bearing pins 66) are arranged, in particular, rotationally fixed, and in particular held or fastened, on a second radial inner surface S2.For example, the respective compensating bolt is formed separately from the support element 74 and thus separately from the second cylinder section 80 and is held, in particular in a rotationally fixed manner, on the first cylinder section 78 and thus on the support element 74, in particular attached. In the first embodiment of Fig. 1, a one-piece support element 74a is also included, comprising a plate section 76a and a first cylinder section 78a. Planet gear pins of the first planet gear carrier 36 are advantageously integrally connected to the one-piece support element 74a of the first embodiment. Furthermore, it can be seen from Fig. 1 and Fig. 2 that the ring gear 38 is permanently connected to the sun gear 40 in a rotationally fixed manner. In the second embodiment, the electric machine 16 is designed as an axial flux machine whose rotor 20 has two rotor elements 86 and 88, spaced apart from each other in the axial direction and designed, for example, as rotor disks. At least a partial region of the stator 18 is arranged axially between the rotor elements 86 and 88, such that the rotor element 88 is overlapped by the partial region of the stator 18 in a first overlap direction parallel to the axial direction and pointing from the rotor element 86 to the rotor element 88. Consequently, the rotor element 86 is overlapped by the partial region of the stator 18 in a second overlap direction parallel to the axial direction of the drive system 10, opposite to the first overlap direction, and pointing from the rotor element 86 to the rotor element 88. Reference symbol list 10 electric drive system 12 vehicle wheel 14 vehicle wheel 16 electric machine 18 stator 20 rotor 22 arrow 24 machine axis of rotation 26 housing 28 planetary gear set 30 first planet gear set 32 ​​second planet gear set 34 first sun gear 36 first planet carrier 38 first ring gear 40 second sun gear 42 second planet carrier 44 second ring gear 45 axis of rotation 46 differential gear set 48 first crown gear 50 second crown gear 52 first axial end face 54 second axial end face 56 compensating gear 58 differential axis of rotation 60 compensating gear axis of rotation 62 arrow 64 arrow 66 compensating bolt 68 housing wall 70 first switching half 71 third switching half 72 second switching half 74 carrier element 76 disc section 78 first cylinder section 80 second cylinder section 84 planet gear bolt 86 rotor element 88 rotor element S1 first radial inner side S2 second radial inner side SE1 first brake switching element SE2 second brake switching element

Claims

Electric drive system (10) for a motor vehicle, comprising: an electric machine (16) comprising a stator (18) and a rotor (20); a planetary gear set (28) comprising: a first planetary gear set (30) comprising a first sun gear (34), a first planet carrier (36) and a first ring gear (38); and a second planetary gear set (32) comprising a second sun gear (40), a second planet carrier (42) and a second ring gear (44) and arranged radially outside and axially overlapping the first planetary gear set (30) with respect to an axis of rotation (45) of the planetary gear set (28); a first brake switching element (SE1) configured to connect the first ring gear (38) to the housing wall (68) in a rotationally fixed manner, wherein a housing-side switching half (70) of the first brake switching element (SE1) is arranged on the housing wall (68);- a differential gear (46), characterized in that the differential gear has a first crown gear (48), a second crown gear (50) and compensating gears (56) arranged axially between the crown gears (48, 50) and meshing with them, each of which is arranged on a respective bearing pin (66) which is rotationally fixed to the first planet carrier (36) and rotationally fixed to the second ring gear (44), wherein a radially extending housing wall (68) is arranged axially adjacent to the planet gear (28);wherein, with respect to the axis of rotation (45) of the planetary gear (28), the rotor (20), the housing wall (68), the planetary gear (28), the first crown gear (48) and the second crown gear (50) are arranged successively in the following sequence: the rotor (20) - the housing wall (68) - the planetary gear (28) - the first crown gear (48) - the second crown gear (50), wherein a one-piece support element (74) is provided which comprises a plate section (76), a first cylinder section (78) and a second cylinder section (80), wherein planet gear pins (84) for first planet gears (P1) of the planetary gear (28) are arranged on the plate section (76), wherein the second ring gear (44) is arranged on a radial inner surface (S1) of the first cylinder section (78), and wherein the bearing pins (66) are arranged on a radial inner surface (S2) of the second cylinder section (80) as Compensating bolts for the compensating gears (56) are arranged.; Electric drive system (10) according to claim 1 , characterized by a second brake switching element (SE2) which is designed to connect the second planet carrier (42) to a housing (26) of the electric drive system (10) in a rotationally fixed manner. Electric drive system (10) according to claim 1 or 2, characterized in that the first ring gear (38) is permanently connected to the second sun gear (40) in a rotationally fixed manner. Electric drive system (10) according to one of the preceding claims, characterized in that the electric machine (16) is designed as an axial flux machine. Motor vehicle, with an electric drive system (10) according to one of the preceding claims.

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