Electric drive device for a motor vehicle

Abstract

Electric drive device (10, 110) for a motor vehicle, comprising a housing (12), a first planetary gear set (18) arranged in the housing (12), which has a first sun gear (22), a first planet carrier (24), and a first ring gear (26) as first elements, a second planetary gear set (20) arranged in the housing (12), which has a second sun gear (30) that can be coupled to the first ring gear (26) in a rotationally fixed manner, a second planet carrier (32), and a second ring gear (34), an electric machine (40) that has a stator (42) and a rotor (44), an input shaft (50) that can be driven by the rotor (44) and is permanently connected to the first sun gear (22) in a rotationally fixed manner, an output shaft (52), a differential gear (54), a side shaft (76), and a first shifting element (56) that is provided to shift the first ring gear (26) to be connected to the housing (12) in a rotationally fixed manner,wherein the rotor (44), the first planetary gear set (18), the second planetary gear set (20) and the differential gear (54) are arranged coaxially to one another, and wherein the side shaft (76) is arranged between the differential gear (54) and a wheel of the motor vehicle and passes through the rotor (44), wherein, - the second planet carrier (32) is permanently connected to the housing (12) in a rotationally fixed manner, - a second switching element (58, 158) is provided for connecting the second sun gear (30) in a rotationally fixed manner to the first ring gear (26), wherein the first planet carrier (24) is permanently connected in a rotationally fixed manner to the second ring gear (34), wherein the second switching element (58, 158) is arranged axially between the first planetary gear set (18) and the second planetary gear set (20), - the differential gear (54) has a ball differential (60) with a differential housing (62) which is permanently connected in a rotationally fixed manner to the first planet carrier (24); - the first switching element (56) is arranged radially surrounding and axially at least partially overlapping the first planetary gear set (18), characterized in that - the first sun gear (22) is arranged axially next to the differential housing (62), wherein a largest outer diameter of the differential housing (62) is larger than an outer diameter of the first sun gear (22); - the second sun gear (30) is arranged axially overlapping the differential housing (62), wherein an inner diameter of the second sun gear (30) is larger than the largest outer diameter of the differential housing (62); wherein a parking lock gear (98) is arranged axially between the first planetary gear set (18) and the second planetary gear set (20), wherein the parking lock gear (98) is connected in a rotationally fixed manner to the second sun gear (30).

Description

[0001] The invention relates to an electric drive device for a motor vehicle according to the preamble of patent claim 1.

[0002] Such an electric drive device for a motor vehicle is already known, for example, from JP H05-116 549 A. The electric drive device has a housing, a first planetary gear set and a second planetary gear set. The planetary gear sets are arranged in the housing. The first planetary gear set has a first sun gear, a first planet carrier and a first ring gear, wherein the first sun gear, the first planet carrier and the first ring gear are first elements of the first planetary gear set or are also referred to as first elements of the first planetary gear set. The second planetary gear set has a second sun gear that is or can be coupled in a rotationally fixed manner to the first ring gear, a second planet carrier and a second ring gear that is or can be coupled in a rotationally fixed manner to the first planet carrier.The second sun gear, the second planet carrier and the second ring gear are second elements of the second planetary gear set or are also referred to as second elements of the second planetary gear set.

[0003] Such drive devices are also known from DE 10 2018 008 939 B3 and the generic DE 10 2017 006 266 A1.

[0004] The object of the present invention is to further develop an electric drive device of the type mentioned at the outset in such a way that a particularly efficient operation and a particularly compact design of the drive device can be realized.

[0005] This object is achieved by an electric drive device having the features of patent claim 1. Advantageous embodiments with expedient further developments of the invention are specified in the remaining claims.

[0006] The starting point is an electric drive device for a motor vehicle which has a housing. A first planetary gear set is arranged in the housing and has a first sun gear, a first planet carrier and a first ring gear as first elements. Furthermore, a second planetary gear set is arranged in the housing and has a second sun gear that can be coupled to the first ring gear (26) in a rotationally fixed manner, a second planet carrier and a second ring gear as second elements. The electric drive device also has an electric machine which has a stator and a rotor. Furthermore, an input shaft which can be driven by the rotor and is permanently connected to the first sun gear in a rotationally fixed manner, an output shaft and a differential gear with a sideshaft are provided.

[0007] A first switching element is provided for connecting the first ring gear (26) to the housing (12) in a rotationally fixed manner, wherein the rotor, the first planetary gear set, the second planetary gear set and the differential gear are arranged coaxially to one another, and wherein the sideshaft is arranged between the differential gear and a wheel of the motor vehicle and passes through the rotor.

[0008] In order to further develop an electric drive device of the type specified in the preamble of patent claim 1 in such a way that a particularly low-loss and thus efficient operation as well as a particularly compact design of the electric drive device can be realized, it is further assumed that, on the one hand, the second planet carrier is permanently connected to the housing in a rotationally fixed manner.

[0009] Furthermore, a second switching element is provided in a known manner, by means of which the second sun gear (30) can be connected in a rotationally fixed manner to the first ring gear (26), wherein the first planet carrier (24) is permanently connected in a rotationally fixed manner to the second ring gear (34).

[0010] Furthermore, it is provided in a known manner that the differential gear has a ball differential with a differential housing, wherein the differential housing is permanently connected in a rotationally fixed manner to the first planet carrier.

[0011] The ball differential is preferably a bevel gear differential, which has differential gears rotatably mounted on the differential housing. The ball differential also has output gears that mesh with the differential gears. The differential gears and the output gears are gears of the ball differential, with the gears preferably being designed as bevel gears. The output gears can be driven by the differential gears, and output shafts, for example, can be driven via the output gears. The differential gears, in turn, can be driven by the differential housing. The output shafts, which are designed, for example, as drive shafts and / or also referred to as side shafts, can drive, for example, individual wheels of the motor vehicle.The ball differential is characterized in particular by the fact that the differential housing defines a receiving space or receiving area in which the aforementioned gears are at least partially, in particular at least predominantly or completely, arranged or accommodated. The receiving space or receiving area is at least substantially round, spherical, or spherical-segment-shaped on the inner circumference.

[0012] The ball differential has a function that is already well known from the general state of the art.

[0013] Furthermore, it is provided in a known manner that the first shifting element is arranged radially surrounding and axially overlapping the first planetary gear set. The feature that the first shifting element is arranged radially surrounding the first planetary gear set is to be understood in particular as meaning that at least a partial region of the first planetary gear set is covered outwards in the radial direction of the first planetary gear set by the first shifting element. Thus, for example, the first shifting element surrounds the partial region of the first planetary gear set at least partially, in particular at least predominantly or completely, circumferentially in the circumferential direction running around the axial direction of the first planetary gear set.The feature that the first shifting element is arranged axially overlapping the first planetary gear set is to be understood as meaning that at least a part of the first planetary gear set is covered by the first shifting element in the axial direction of the planetary gear set or in a direction coinciding with the axial direction of the first planetary gear set.

[0014] According to the invention, the first sun gear is arranged axially, i.e., in the axial direction of the coaxially arranged planetary gear sets, next to the differential housing. The largest outer diameter of the differential housing is larger than an outer diameter, in particular the largest outer diameter, of the first sun gear.

[0015] The respective element of the respective planetary gear set is rotatable about an axis of rotation, also referred to as the main axis of rotation, relative to the housing when the respective element is not connected to the housing in a rotationally fixed manner, i.e. is not fixed to the housing in a rotationally fixed manner, or rotates about the main axis of rotation relative to the housing when the respective planetary gear set is driven, i.e. when a torque is introduced into the respective planetary gear set. The axial direction of the respective planetary gear set coincides with the said main axis of rotation, with the axial direction of the electric drive device as a whole coinciding with the main axis of rotation. The radial direction of the respective planetary gear set runs perpendicular to the axial direction.The first elements, the second elements and the housing are respective components of the drive device or are also referred to as respective components of the drive device.

[0016] Furthermore, it is provided according to the invention that the second sun gear is arranged axially, i.e. in the axial direction of the respective planetary gear set, overlapping the differential housing, so that at least a partial area of ​​the differential housing is covered or overlapped by the first sun gear in a direction coinciding with the axial direction of the respective planetary gear set.

[0017] The feature that the planetary gear sets are arranged coaxially with the differential gear means, in particular, that the main axis of rotation coincides with the differential axis of rotation. The main axis of rotation also corresponds to an axis of rotation of the input shaft and an axis of rotation of the output shaft.

[0018] According to the invention, a parking lock gear is further provided which is arranged axially between the first planetary gear set and the second planetary gear set, wherein the parking lock gear is connected in a rotationally fixed manner to the second sun gear.

[0019] Overall, this results in a compact electric drive device that allows for two well-graded gears.

[0020] In the context of the invention, a rotationally fixed connection of two, in particular rotatably mounted, elements is to be understood in particular as meaning that the two rotationally fixed elements are arranged coaxially to one another and are connected to one another in such a way that they rotate at the same angular speed, in particular when they are driven.

[0021] A rotationally fixed connection of an element, in particular a rotatably mounted element, to the housing is to be understood as meaning that the element connected to the housing in a rotationally fixed manner is connected to the housing in such a way that the element connected to the housing in a rotationally fixed manner cannot be rotated relative to the housing, i.e. that the element connected to the housing in a rotationally fixed manner is secured against relative rotations relative to the housing.

[0022] A permanently rotationally fixed coupling or connection is to be understood in the context of the invention in particular as meaning that two components that are permanently connected to one another in a rotationally fixed manner are permanently, i.e. always or permanently, connected or coupled to one another in a rotationally fixed manner, so that no coupling device or switching element is provided by means of which this permanently rotationally fixed coupling or connection could be canceled or which can be switched between a coupling state that effects the rotationally fixed coupling and a decoupling state that cancels the rotationally fixed coupling.

[0023] The first shifting element can, for example, be switched between a first connected state and a first released state. The first connected state corresponds, for example, to at least one first connected position, wherein the first released state corresponds, for example, to at least one first released position. Thus, for example, the first shifting element can be moved, in particular relative to the housing and / or translationally, between the first connected position and the first released position. In the first connected state, the first ring gear is connected to the housing in a rotationally fixed manner by means of the first shifting element, such that the first ring gear does not rotate or cannot rotate relative to the housing, in particular even when the first planetary gear set is driven.In the first release state, however, the first switching element releases the first ring gear for rotation relative to the housing, so that the first ring gear rotates or can rotate relative to the housing, in particular about the main axis of rotation, when the first planetary gear set is driven.

[0024] The second switching element can be switched, for example, between a second connected state and a second released state. The second connected state corresponds, for example, to at least one second connected position of the second switching element, wherein the second released state corresponds, for example, to at least one second released position of the second switching element. The second switching element can be moved, for example, in particular translationally and / or relative to the housing, between the second connected state and the second released state. In the second connected state, the second sun gear is rotationally fixedly connected to the first ring gear by means of the second switching element.In the second release state, the second sun gear and the first ring gear are not connected in a rotationally fixed manner, so that the second sun gear rotates or can rotate relative to the first ring gear about the main axis of rotation when the second planetary gear set is driven.

[0025] A first development of the invention provides that the second shifting element is arranged axially between the first planetary gear set and the second planetary gear set. This allows the second shifting element to be arranged in a space-saving manner. Particularly advantageously, a power transmission region of the second shifting element is arranged radially between a toothing of the first sun gear and a toothing of the second sun gear. The power transmission region of the second shifting element refers to a region of a disk pack of the second shifting element or a toothing of the second shifting element.

[0026] In a further development, the electric drive device has a first axial bearing, which is designed to axially support the first planetary carrier relative to the first ring gear. In the context of the invention, an axial bearing is generally understood to mean a bearing that can absorb axial forces. The first axial bearing is particularly advantageously arranged axially, i.e., in the axial direction of the respective planetary gear set, between the first planetary gear set and the second planetary gear set. This allows for a low-loss bearing arrangement in a particularly space-efficient manner.

[0027] A further advantageous development is characterized in that the electric drive device has a second axial bearing, which is arranged axially between the second sun gear and a second ring gear shaft of the second ring gear, wherein the second axial bearing is arranged axially on a side of the second planetary gear set facing away from the first planetary gear set. This allows the installation space requirement to be kept particularly low.

[0028] In addition to the second axial bearing, a third axial bearing can be provided. The third axial bearing is designed to axially support the second planet carrier against the second ring gear, wherein the third axial bearing is arranged axially on a side of the second axial bearing facing away from the second planetary gear set. In other words, for example, the third axial bearing can support the second planet carrier in the axial direction against the second ring gear or on the second ring gear, or is supported and thus supported, so that an efficient and low-loss bearing arrangement can be realized in a space-saving manner.

[0029] A further development provides a fourth axial bearing, by means of which the second sun gear is axially supported relative to the first ring gear. The fourth axial bearing is advantageously arranged radially overlapping the first axial bearing. The fourth axial bearing is advantageously arranged axially on a side of the first axial bearing facing away from the first planetary gear set.

[0030] A further development provides a fifth axial bearing, which is designed to support the differential housing and, with it, the first planetary carrier against the housing. The fifth axial bearing is arranged axially on the side of the second planetary gear set facing away from the first planetary gear set and thus on the "output side" of the second planetary gear set and radially within the largest outer diameter of the differential housing. The fifth axial bearing is advantageously arranged axially adjacent to the fourth axial bearing. The differential housing is also referred to, for example, as a differential cage or is designed as a differential cage on which at least the differential gears can be rotatably mounted.

[0031] Particularly advantageously, exactly four axial bearings are provided, namely the first axial bearing, the second axial bearing, the fourth axial bearing and the fifth axial bearing, wherein the first axial bearing is arranged axially between the first and the second planetary gear set and the second axial bearing, the fourth axial bearing and the fifth axial bearing are arranged axially on the side facing away from the first planetary gear set.

[0032] A further development provides a first radial bearing which is designed to support the first planet carrier radially against the first sun gear, wherein the first radial bearing is arranged axially on a side of the first planetary gear set facing away from the second planetary gear set.

[0033] A further development provides for a second radial bearing, which is designed to support the second sun gear against the differential housing.

[0034] A further development provides a third radial bearing which is designed to support the first ring gear radially against the differential housing.

[0035] In order to achieve particularly comfortable operation while saving space, it is particularly advantageous for the first shifting element to be designed as a multi-plate shifting element. The first shifting element comprises, for example, a plurality of plates, in particular friction plates, arranged one behind the other or consecutively in the axial direction, which can be pressed or compressed. As a result, the first shifting element can, for example, connect at least or exactly two of the components to one another in a rotationally fixed manner, in particular exclusively by frictional engagement.

[0036] It has proven advantageous if the second switching element has at least one positive-locking element and is thus preferably designed as a positive-locking switching element, in particular as a claw clutch. This ensures particularly efficient operation.

[0037] The feature that the second switching element has at least one positive locking element can be understood in particular as the following: In a first variant, the positive locking element can be a positive locking switching element per se, in particular a claw clutch. In the first variant, it is preferably provided that the second switching element exclusively or only has the positive locking element and is thus designed, for example, as a whole as a positive locking switching element, in particular as a claw clutch. As a result, for example, the second switching element in the first variant exclusively enables a positive, rotationally fixed connection. In a second variant, it is conceivable that the positive locking element per se is designed as a positive locking switching element, in particular as a claw clutch.In the second variant, the second switching element additionally comprises a frictional switching element, in particular a multi-disk switching element. Thus, for example, in the second variant, the second switching element enables a positive, non-rotatable connection through the positive-locking element and a force-locking or frictional non-rotatable connection through the multi-disk element.

[0038] In a third variant, it is conceivable that the form-locking element is designed, in particular, as a switchable freewheel. In the third variant, the second switching element as a whole or per se is preferably designed, in particular, as a switchable freewheel, so that in the third variant the second switching element only or exclusively has the switchable freewheel as the form-locking element. Thus, in the third variant, the second switching element only enables a form-locking, rotationally fixed connection. In a fourth variant, it can be provided that the form-locking element is designed as the previously described freewheel, in particular as the previously described switchable freewheel. In the fourth variant, the second switching element additionally comprises a frictional or non-positive switching element, such as a multi-disk switching element.Thus, in the fourth variant, the second switching element can enable a non-positive or frictional rotational connection as well as a positive rotational connection. The respective freewheel ensures that the one second element is connected in a first direction running around the main axis of rotation to the housing or to the one first element in a first direction, which runs around the main axis of rotation, and the freewheel prevents relative rotations around the main axis of rotation in the first direction of rotation between the one second element and the housing or the one first element. However, in a second direction of rotation running around the main axis of rotation and opposite to the first direction of rotation, the freewheel opens, so that the freewheel allows relative rotations in the second direction of rotation between the one second element and the housing or the one first element.Thus, depending on the direction of rotation, the one second element is braked or not braked by means of the freewheel, or is connected to the housing with the one first element in a rotationally fixed manner or not. If necessary or optionally, the freewheel is switchable so that it can be switched on and off. If the freewheel is switched on, the freewheel connects the one second element to the housing or to the one first element in the first direction of rotation and allows relative rotation between the one second element and the housing or the one first element in the second direction of rotation. If the freewheel is switched off, the freewheel allows relative rotations between the one second element and the housing or the one first element, for example, in both the first direction of rotation and the second direction of rotation.

[0039] Further advantages, features and details of the invention will become apparent from the following description of preferred embodiments and from the figures.

[0040] The drawing shows: Fig. 1 a schematic representation of a transmission part of a first embodiment of an electric drive device according to the invention for a motor vehicle, Fig. 2 a schematic representation of a transmission part of a second embodiment of the electric drive device according to the invention, Fig. 3 a detailed schematic representation of the first embodiment Fig. 4 a detailed schematic representation of the second embodiment.

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

[0042] Fig. 1 and Fig. 3 show a schematic representation of a first embodiment of an electric drive device 10 for a motor vehicle, in particular for a motor vehicle such as a passenger car. Fig. 1 only shows a schematically illustrated planetary gear 16 of the first embodiment.

[0043] Fig. 2 and Fig. 4 show a schematic representation of a second embodiment of an electric drive device 110. Fig. 2 shows a schematically illustrated planetary gear 116 of the second embodiment.

[0044] The electric drive device 10, 110 intended for driving a motor vehicle comprises a housing 12 in both embodiments.

[0045] The electric drive device 10 according to the Fig. 1 and Fig. 3 further comprises the planetary gear 16, which is arranged or accommodated in the housing 12. The planetary gear 16, and thus the drive device 10, comprises a first planetary gear set 18 and a second planetary gear set 20, which are arranged coaxially to one another. The first planetary gear set 18 has a first sun gear 22, a first planet carrier 24, and a first ring gear 26. The first sun gear 22, the first planet carrier 24, and the first ring gear 26 are first elements of the first planetary gear set 18, or are also referred to as first elements. In addition, the first planetary gear set 18 comprises at least one first planet gear 28, which is rotatably mounted on the planet carrier 24 and simultaneously meshes with the sun gear 22 and the ring gear 26.

[0046] The second planetary gear set 20 has a second sun gear 30, a second planet carrier 32 permanently connected to the housing 12 in a rotationally fixed manner, and a second ring gear 34. The second sun gear 30, the second planet carrier 32, and the second ring gear 34 are second elements of the second planetary gear set 20 or are also referred to as second elements. The sun gears 22 and 30, the planet carriers 24 and 32, the ring gears 26 and 34, and the housing 12 are also referred to as components of the drive device 10. The planetary gear sets 18 and 20 are received or arranged in the housing 12. The second planetary gear set 20 further comprises at least one second planet gear 36, which is rotatably mounted on the planet carrier 32 and simultaneously meshes with the sun gear 30 and the ring gear 34. The planet carriers 24 and 32 are also referred to as webs.

[0047] In particular, when the respective element is not connected to the housing 12 in a rotationally fixed manner, the respective element can rotate about an axis of rotation, also referred to as the main axis of rotation 38, relative to the housing 12, or the respective element rotates about the main axis of rotation 38 relative to the housing 12, in particular when the respective planetary gear set 18 or 20 is driven, i.e. when a torque is introduced into the respective planetary gear set 18 or 20. Alternatively or additionally, the respective components can rotate about the main axis of rotation 38 relative to one another, in particular when the respective components are not connected to one another in a rotationally fixed manner. If, for example, two of the components are connected to one another in a rotationally fixed manner or are coupled to one another in a rotationally fixed manner, the components connected to one another in a rotationally fixed manner are secured against rotation relative to one another.If, for example, two of the elements are connected or coupled to one another in a rotationally fixed manner, and the planetary gear sets 18 and 20 are driven, the elements connected in a rotationally fixed manner rotate together and thus as a block about the main axis of rotation 38, in particular relative to the housing 12. This means that the elements connected in a rotationally fixed manner then rotate as a block. If, for example, the respective element is connected or coupled to the housing 12 in a rotationally fixed manner, the respective element is secured against rotation relative to the housing 12 and about the main axis of rotation 38, such that the respective element connected in a rotationally fixed manner to the housing 12 cannot rotate relative to the housing 12 about the main axis of rotation 38.

[0048] From the Fig. 1 to 4 it can be seen that in both embodiments the second ring gear 34 is connected in a rotationally fixed manner to the first planet carrier 24.

[0049] The drive device 10 further comprises a schematically illustrated electric machine 40, by means of which the motor vehicle can be electrically driven. For example, at least or exactly two wheels of the motor vehicle that are spaced apart from one another in the transverse direction of the vehicle can be electrically driven by means of the electric machine 40. By electrically driving the wheels, the motor vehicle as a whole can be electrically driven. For this purpose, the electric machine 40 comprises a Fig. 3 schematically illustrated stator 42 and a rotor 44. The rotor 44 is rotatable about a machine rotation axis 46 relative to the stator 42. The machine rotation axis 46 coincides with the main rotation axis 38. In particular, the rotor 44 is drivable by the stator 42 and thus rotatable about the machine rotation axis 46 relative to the stator 42. The electric machine 40 can be operated in motor mode and thus as an electric motor. In motor mode, the stator 42 drives the rotor 44, whereby the rotor 44 is rotated relative to the stator 42 about the machine rotation axis 46. Via the rotor 44, the electric machine 40 can provide torques for, in particular, purely electrically driving the wheels and thus the motor vehicle. This respective torque provided by the electric machine 40 via the rotor 44 for electrically driving the wheels is in Fig. 1 is illustrated by an arrow 48.

[0050] The drive device 10, in particular the planetary gear 16, has an input shaft 50 which is permanently connected in a rotationally fixed manner to the first sun gear 22 and which can be driven by the rotor 44 and is rotatable in particular about the main axis of rotation 38 or about the machine axis of rotation 46 relative to the housing 12. For example, the input shaft 50 is permanently connected in a rotationally fixed manner to the rotor 44. The elements of the planetary gear sets 18 and 20 and the input shaft 50 are also referred to, for example, as components. With respect to a torque flow running from the rotor 44 via the planetary gear 16 to the wheels, via which torque the respective torque provided by the electric machine 40 via its rotor 44 is transmitted from the rotor 44 to the wheels, the input shaft 50 is the first of the components to which the respective torque provided by the electric machine is transmitted.In other words, the input shaft 50 is arranged upstream of the other, or all, components in the torque flow. Thus, the respective torque provided by the electric machine 40 via the rotor 44 is transmitted first to the input shaft 50 and only then to the remaining, or other, components. This allows, for example, the respective torque provided by the electric machine 40 to be introduced into the planetary gear 16 via the input shaft 50.

[0051] The drive device 10, in particular the planetary gear 16, has an output shaft 52 rotatable about the main rotational axis 38 relative to the housing 12, via which the planetary gear 16 can provide torques in the form of output torques, in particular for driving the wheels. The respective output torque results from the respective torque provided by the electric machine 40. The respective output torque can be output from the planetary gear 16 via the output shaft 52.

[0052] The drive device 10 further comprises a differential gear 54, also simply referred to as a differential. The differential gear 54 is assigned to the axle, for example, and is thus also simply referred to as an axle gear. For example, the wheels of the axle can be driven by the electric machine 40 via the differential gear 54. Thus, the differential gear 54 has the particular function of distributing the respective torque provided by the electric machine 40 to the wheels. The differential gear 54 also has the function of allowing speed compensation between the wheels or different speeds of the wheels, for example when the motor vehicle is cornering. The differential gear 54 can be driven by the output shaft 52 or, via the output shaft 52, by the planetary gear 16, as will be explained in more detail below.

[0053] The drive device 10 has a first shifting element 56, by means of which the first ring gear 26 can be connected in a rotationally fixed manner to the housing 12. Furthermore, the drive device 10 has a second shifting element 58, by means of which the second sun gear 30 can be connected in a rotationally fixed manner to the first ring gear 26. The planetary gear sets 18 and 20 are arranged coaxially with the differential gear 54.

[0054] In order to achieve a particularly compact design and particularly efficient operation of the drive device 10, the differential gear 54 has a ball differential 60, also referred to as a bevel gear differential and / or a bevel gear differential, with a differential housing 62, also referred to as a differential carrier or differential cage. The output shaft 52 is permanently connected to the differential housing 62 in a rotationally fixed manner. The respective output torque provided by the output shaft 52 is thereby transmitted to the differential housing 62, whereby the differential housing 62 can be driven or is driven.

[0055] Out of Fig. 3 shows that the differential housing 62 defines a receiving space 64. The ball differential 60 is designed as a bevel gear differential, which has two differential gears 66 and 68 rotatably mounted on the differential housing 62 and two output gears 70 and 72 that are rotatable, in particular relative to the differential housing 62. The output gears 70 and 72 mesh simultaneously with the differential gears 66 and 68. The differential gears 66 and 68 and the output gears 70 and 72 are gears designed as bevel gears. The gears are arranged at least partially, in particular at least predominantly or completely, in the receiving space 64.

[0056] The output gears 70 and 72 are connected, in particular permanently, in a rotationally fixed manner to respective shafts 74 and 76, also referred to as side shafts. The aforementioned wheels of the motor vehicle can be driven via the shafts 74 and 76, so that the wheels can be driven via the shafts 74 and 76 by the output gears 70 and 72 and thus by the differential gear 54.

[0057] In Fig. 3 and Fig. 4, respective arrows 78 and 80 illustrate a respective drive torque resulting from the respective output torque, by means of which the respective wheel or the respective shaft 74 or 76 can be driven or is driven. If the differential housing 62 is rotated about the main axis of rotation 38, in particular relative to the housing 12, the differential gears 66 and 68 are rotated about the main axis of rotation 38, in particular relative to the housing 12. Then, for example, the output gears 70 and 72 and, via these, the shafts 74 and 76 and thus the wheels are driven by the differential gears 66 and 68, whereby the motor vehicle as a whole can be driven.

[0058] The differential housing 62 is permanently connected in a rotationally fixed manner to the first planet carrier 24 or to the output shaft 52. Furthermore, the first sun gear 22 is arranged axially next to the differential housing 62, wherein a largest outer diameter of the differential housing 62 is larger than an outer diameter, in particular than a largest outer diameter, of the first sun gear 22. This means that the differential housing 62 projects outwardly beyond the first sun gear 22 in a radial direction perpendicular to the axial direction of the respective planetary gear set 18 or 20.

[0059] The second sun gear 30 is arranged axially at the level of the differential housing 62, so that at least a part of the differential housing 62 is surrounded outwardly by the second sun gear 30 in the radial direction of the respective planetary gear set 18 or 20 and thus in the radial direction of the drive device 10.

[0060] In this case, an inner diameter of the second sun gear 30 is larger than the largest outer diameter of the differential housing 62. In particular, it is conceivable that at least a portion of the differential housing 62, in particular the largest outer diameter of the differential housing 62, is arranged radially inside the sun gear. Thus, the sun gear 30 is designed, for example, in the manner of a hollow shaft through which the differential housing 62 passes. Viewed in the direction of the main axis of rotation 38, i.e., in the axial direction, the differential housing 62 completely overlaps the second sun gear 30.

[0061] The first switching element 56 is arranged radially surrounding and axially overlapping the first planetary gear set 18.

[0062] The second shift element 58 is arranged axially between the first planetary gear set 18 and the second planetary gear set 20.

[0063] The electric drive device 10 comprises a first axial bearing 82, via which the first planetary carrier 24 is supported and thus mounted in the axial direction relative to the first ring gear 26. The first axial bearing 82 is arranged in the axial direction between the first planetary gear set 18 and the second planetary gear set 20.

[0064] At the Fig. In the first embodiment shown in Figure 3, a parking lock gear 98 of a parking lock 96 is arranged axially between the first planetary gear set 18 and the second planetary gear set 20. Advantageously, in the first embodiment, the first planetary gear set 18, the first axial bearing 82, the parking lock gear 98, and the second planetary gear set 20 are arranged one after the other in the axial direction in the order mentioned.

[0065] The electric drive device 10 further comprises a second axial bearing 84 by means of which the second sun gear 30 can be supported or is supported and thus mounted in the axial direction on the second planet carrier 32, wherein the second axial bearing 84 is arranged axially on the output side of the second planet carrier 32 of the second planetary gear set 20.

[0066] Furthermore, a third axial bearing 86 is provided, by means of which the second planet carrier 32 is supported and thus mounted in the axial direction on the second ring gear 34 or a second ring gear shaft 34a that is connected in a rotationally fixed manner to the second ring gear 34. The third axial bearing 86 is arranged axially on a side of the second axial bearing 84 facing away from the second planetary gear set 20. The third axial bearing 86 is not absolutely necessary. Alternatively, the second sun gear 30 can be supported axially relative to the second ring gear 34 by means of the second axial bearing 84.

[0067] By means of a fourth axial bearing 87, the first ring gear 26 is axially supported relative to the second sun gear 30.

[0068] The parking lock gear 98 of the first embodiment is, as shown in Fig. 3, is connected in a rotationally fixed manner to the second sun gear 30.

[0069] The differential housing 62 is axially supported relative to the housing 12 by means of a fifth axial bearing 90. The fifth axial bearing 90 is advantageously arranged axially on a side of the second planetary gear set 20 facing away from the first planetary gear set 18 and radially within the largest outer diameter of the differential housing 62, so that, for example, the differential housing 62 projects radially outward beyond the fifth axial bearing 90.

[0070] The arrangement of the axial bearings 82, 84, 86, 87, and 90 allows all axial forces in both directions coinciding with the axial direction to be efficiently transferred from the planetary gear 16, 216 into the housing 12. Particularly advantageous is the possibility of arranging the axial bearings 82, 84, and 86 with the same or similar diameter, so that an at least essentially linear force flow can be ensured.

[0071] The electric drive device 10, in particular the planetary gear 16, further comprises a first radial bearing 88, by means of which the first planet carrier 24 is supported in the radial direction against the first sun gear 22. The first radial bearing 88 is advantageously arranged on the input side, i.e., axially on a side facing away from the second planetary gear set, of the first planetary gear set 18.

[0072] A second radial bearing 89 of the electric drive device 10 is provided to support the second sun gear 30 radially relative to the differential housing 62.

[0073] A third radial bearing 91 is provided to support the first ring gear 26 radially relative to the differential housing 62.

[0074] Particularly advantageously, exactly three radial bearings are provided within the planetary gear 16, namely the first radial bearing 88, the second radial bearing 89 and the third radial bearing 91.

[0075] The first switching element 56 is advantageously designed as a brake, in particular as a friction brake, and thereby as a multi-disk switching element, that is to say as a multi-disk brake.

[0076] In contrast, the second switching element 58, 158 has at least one positive locking element in both embodiments.

[0077] Since the first shift element 56 is designed as a multi-disk shift element, the first shift element 56 has an inner disk carrier 92. The inner disk carrier 92 is particularly advantageously formed integrally with the first ring gear 26.

[0078] In both embodiments, the electric machine 40 is designed as an internal rotor, so that at least a longitudinal portion of the rotor 44 is arranged within the stator 42, or is covered radially outward by the stator 42. Of course, it is alternatively conceivable for the electric machine 40 to be designed as an external rotor.

[0079] The arrangement of the axial bearings 82, 84, 86, 87, 90 and the radial bearings 88, 89, 91 relative to the elements of the first planetary gear set 18 and to the elements of the second planetary gear set 20 is, as shown in the Fig. 3 and Fig. 4, is the same in both embodiments. Only the arrangement of the bearings 82, 84, 86, 87, 90, 88, 89, 91 relative to the parking lock gear differs in the two embodiments, which will be described in more detail below.

[0080] The electric drive device 110 in its second embodiment differs from the electric drive device 10 in the first embodiment in particular with regard to an arrangement of the parking lock 96, 196 and with regard to a detailed design of the second switching element 58, 158.

[0081] At the Fig. In the first embodiment shown in Figure 3, a first coupling element 58a of the second shifting element 58 is arranged in a rotationally fixed and axially displaceable manner with respect to the parking lock gear 98. A sliding sleeve 58c is connected in a rotationally fixed and axially fixed manner to the first coupling element 58a. A second coupling element 58b of the second shifting element 58 is connected in a rotationally fixed and axially fixed manner to the first ring gear 26. The sliding sleeve 58c is advantageously arranged axially on a side of the parking lock gear 98 facing away from the second planetary gear set 20. In the first embodiment, the second shifting element 58 is arranged axially directly adjacent to the parking lock gear 98.

[0082] The Fig. 2 and Fig.The second embodiment of the electric drive device 110 shown in Fig. 4 has a planetary gear 116 in which a parking lock gear 198 of a parking lock 196 is connected in a rotationally fixed manner to the differential housing 62 and is arranged on a side of the second planetary gear set 20 facing away from the first planetary gear set 18.

[0083] Furthermore, the second embodiment differs from the first embodiment in that a first coupling element 158a of a second shifting element 158 ​​is connected in a rotationally fixed and axially fixed manner to the second sun gear 30. In the second embodiment, a sliding sleeve 158c is arranged in a rotationally fixed and axially displaceable manner relative to the second sun gear 30, with the second shifting element 158 ​​being arranged axially directly adjacent to the second sun gear 30. A second coupling element 158b is connected in a rotationally fixed manner to the first ring gear 26, essentially as in the first embodiment. List of reference symbols 10; 110 drive device 12 housings 16, 116 planetary gears 18 first planetary gear set 20 second planetary gear set 22 first sun gear 24 first planet carrier 26 first ring gear 28 first planetary gear 30 second sun gear 32 second planet carrier 34 second ring gear 34a Second ring gear shaft 36 second planet gear 38 Main axis of rotation 40 Electric Machine 42 Stator 44 Rotor 46 Machine rotation axis 48 Arrow 50 input shaft 52 Output shaft 54 differential gears 56 first switching element 58, 158 second switching element 58a, 158a First coupling element 58b, 158b Second coupling element 58c, 158c sliding sleeve 60 ball differential 62 differential housing 64 recording room 66 balance wheel 68 balance wheel 70 Output gear 72 Output gear 74 Wave 76 Wave 78 Arrow 80 Arrow 82 First thrust bearing 84 Second thrust bearing 86 Third thrust bearing 87 Fourth thrust bearing 88 First radial bearing 89 Second radial bearing 90 Fifth thrust bearing 91 Third radial bearing 92 inner disc carrier 96, 196 parking lock 98, 198 parking lock gear

Claims

[1] Electric drive device (10, 110) for a motor vehicle, comprising a housing (12), a first planetary gear set (18) arranged in the housing (12), which has as first elements a first sun gear (22), a first planet carrier (24) and a first ring gear (26), a second planetary gear set (20) arranged in the housing (12), which has as second elements a second sun gear (30) which can be coupled in a rotationally fixed manner to the first ring gear (26), a second planet carrier (32) and a second ring gear (34), an electric machine (40) which has a stator (42) and a rotor (44), an input shaft (50) which can be driven by the rotor (44) and is permanently connected in a rotationally fixed manner to the first sun gear (22), an output shaft (52), a differential gear (54), a side shaft (76) and a first switching element (56) which is provided to to connect the first ring gear (26) to the housing (12) in a rotationally fixed manner,wherein the rotor (44), the first planetary gear set (18), the second planetary gear set (20) and the differential gear (54) are arranged coaxially to one another, and wherein the side shaft (76) is arranged between the differential gear (54) and a wheel of the motor vehicle and passes through the rotor (44), wherein, - the second planet carrier (32) is permanently connected to the housing (12) in a rotationally fixed manner, - a second switching element (58, 158) is provided for connecting the second sun gear (30) in a rotationally fixed manner to the first ring gear (26), wherein the first planet carrier (24) is permanently connected in a rotationally fixed manner to the second ring gear (34), wherein the second switching element (58, 158) is arranged axially between the first planetary gear set (18) and the second planetary gear set (20), - the differential gear (54) has a ball differential (60) with a differential housing (62) which is permanently connected in a rotationally fixed manner to the first planet carrier (24); - the first switching element (56) is arranged radially surrounding and axially at least partially overlapping the first planetary gear set (18), characterized by , that - the first sun gear (22) is arranged axially next to the differential housing (62), wherein a largest outer diameter of the differential housing (62) is larger than an outer diameter of the first sun gear (22); - the second sun gear (30) is arranged axially overlapping the differential housing (62), wherein an inner diameter of the second sun gear (30) is larger than the largest outer diameter of the differential housing (62); wherein a parking lock gear (98) is arranged axially between the first planetary gear set (18) and the second planetary gear set (20), wherein the parking lock gear (98) is connected in a rotationally fixed manner to the second sun gear (30). [2] Electric drive device (10, 110) according to claim 1, characterized byin that a first coupling element (58a) of the second switching element (58) is arranged in a rotationally fixed and axially displaceable manner with respect to the parking lock gear (98), wherein a sliding sleeve (58c) is connected in a rotationally fixed and axially fixed manner to the first coupling element (58a) and wherein a second coupling element (58b) of the second switching element (58) is connected in a rotationally fixed and axially fixed manner to the first ring gear (26), and wherein the sliding sleeve (58c) is arranged axially on a side of the parking lock gear (98) facing away from the second planetary gear set (20). [3] Electric drive device (10, 110) according to one of the preceding claims, characterized bya first axial bearing (82) which is designed to support the first planet carrier (24) axially relative to the first ring gear (26), wherein the first planetary gear set (18), the first axial bearing (82), the parking lock gear (98) and the second planetary gear set (20) are arranged one after the other in the said order, viewed in the axial direction. [4] Electric drive device (10, 110) according to one of the preceding claims, characterized by a second axial bearing (84) which is arranged axially between the second sun gear (30) and a second ring gear shaft (34a) of the second ring gear (34), wherein the second axial bearing (84) is arranged axially on a side of the second planetary gear set (20) facing away from the first planetary gear set (18). [5] Electric drive device (10, 110) according to one of the preceding claims, characterized bya fourth axial bearing (87) by means of which the second sun gear (30) is supported axially relative to the first ring gear (26). [6] Electric drive device (10, 110) according to one of the preceding claims, characterized by a fifth axial bearing (90) which is designed to support the differential housing (62) against the housing (12), wherein the fifth axial bearing (90) is arranged axially on the output side of the second planetary gear set (20) and radially within the largest outer diameter of the differential housing (62). [7] Electric drive device (10, 110) according to one of the preceding claims, characterized by a first radial bearing (88) which is designed to support the first planet carrier (24) radially against the first sun gear (22), wherein the first radial bearing (88) is arranged axially on a side of the first planetary gear set (18) facing away from the second planetary gear set (20). [8] Electric drive device (10, 110) according to one of the preceding claims, characterized by a second radial bearing (89) which is designed to support the second sun gear (30) against the differential housing (62). [9] Electric drive device (10, 110) according to one of the preceding claims, characterized by a third radial bearing (91) which is designed to support the first ring gear (26) radially against the differential housing (62).

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