Drive unit for a vehicle

Abstract

A drive unit for a vehicle, comprising two electric motors (EM1, EM2) and a manual transmission (SG) with two planetary gear sets (PS1, PS2), a first shifting element (D), a second shifting element (E), and a first positive-locking shifting unit with a third shifting element (A), a fourth shifting element (B), and a first sliding sleeve (SM1), wherein the first sun gear shaft (SO1) is rotationally fixedly connected to the input shaft (An), wherein the first carrier shaft (ST1) is rotationally fixedly connected to the second ring gear shaft (HR2), wherein the second carrier shaft (ST2) is rotationally fixedly connected to an output shaft (Ab), wherein the second sun gear shaft (SO2) is rotationally fixedly connected to a stationary component, wherein, in a closed state of the first shifting element (D), the second electric motor (EM2) is drive-effectively connected to the first ring gear shaft (HR1),wherein, in a closed state of the second switching element (E), the second electric machine (EM2) is drivingly connected to the drive shaft (An) and the first sun shaft (SO1), wherein, in a closed state of the third switching element (A), the first ring gear shaft (HR1) is rotationally fixedly connected to the stationary component, wherein, in a closed state of the fourth switching element (B), the first ring gear shaft (HR1) is rotationally fixedly connected to the second carrier shaft (ST2) and the output shaft (Ab).

Description

[0001] The invention relates to a drive unit for a vehicle, wherein the drive unit comprises two electric motors and a manual transmission with multiple gears. The invention also relates to a vehicle having such a drive unit.

[0002] For example, DE 10 2013 214 238 A1 discloses a drive unit for a vehicle, wherein the drive unit has a plurality of electric machines, at least one planetary gear, and a plurality of positive-locking shifting elements. A first electric machine is permanently coupled, directly or indirectly, to a sun gear of a first planetary gear, wherein a second electric machine is directly or indirectly coupled, depending on the shift position of a first positive-locking shifting element and a second positive-locking shifting element, either to the sun gear of the first planetary gear or to a carrier of the first planetary gear. A ring gear of the first planetary gear is coupled, depending on the shift position of a third positive-locking shifting element and a fourth positive-locking shifting element, either to a housing or to the carrier of the first planetary gear.

[0003] Furthermore, DE 10 2019 218 413 A1 discloses a drive unit for an electric vehicle with a manual transmission having a transmission input shaft and a transmission output shaft, wherein the manual transmission is designed as a three-speed manual transmission for shifting three gears, with three shifting elements and two interconnected planetary gear sets. The first planetary gear set has a first sun gear shaft, a first ring gear shaft, and a first carrier shaft. The second planetary gear set has a second sun gear shaft, a second ring gear shaft, and a second carrier shaft. The first carrier shaft is fixedly connected to the second ring gear shaft, wherein the first sun gear shaft forms the transmission input shaft, wherein the second sun gear shaft is fixedly locked to the housing, and wherein the second carrier shaft forms the transmission output shaft.

[0004] The object of the present invention is to provide an alternative drive unit for a vehicle. In particular, the drive unit should be compact. This object is achieved by a drive unit having the features of independent patent claim 1. Advantageous embodiments are the subject of the dependent claims, the following description, and the figures.

[0005] A drive unit for a vehicle according to the invention comprises a first electric machine, a second electric machine, and a manual transmission with a first planetary gear set having a first sun gear shaft, a first ring gear shaft, and a first carrier shaft, a second planetary gear set having a second sun gear shaft, a second ring gear shaft, and a second carrier shaft, a first shifting element, a second shifting element, and a first positive shifting unit having a third shifting element, a fourth shifting element, and a single first sliding sleeve, wherein the manual transmission is drive-connected to the first electric machine via a drive shaft, wherein the first sun gear shaft is rotationally fixedly connected to the drive shaft, wherein the first carrier shaft is rotationally fixedly connected to the second ring gear shaft, wherein the second carrier shaft is rotationally fixedly connected to an output shaft,wherein the second sun gear shaft is rotationally fixedly connected to a stationary component, wherein, in a closed state of the first switching element, the second electric machine is drivingly connected to the first ring gear shaft, wherein, in a closed state of the second switching element, the second electric machine is drivingly connected to the drive shaft and the first sun gear shaft, wherein, in a closed state of the third switching element, the first ring gear shaft is rotationally fixedly connected to the stationary component, whereby at least a first gear is engaged for the first electric machine, wherein, in a closed state of the fourth switching element, the first ring gear shaft is rotationally fixedly connected to the second carrier shaft and the output shaft, whereby at least a second gear is engaged for the first electric machine.

[0006] The manual transmission thus has two planetary gear sets, with the two planetary gear sets arranged axially adjacent to one another to save radial installation space. The first shift unit is arranged radially nested on an outer circumferential surface of the two planetary gear sets, thereby saving axial installation space. The first carrier shaft carries several planetary gears that mesh with the first sun gear shaft and the first ring gear shaft. The second carrier shaft carries several planetary gears that mesh with the second sun gear shaft and the second ring gear shaft.

[0007] For the purposes of the invention, a “shaft” is understood to be a rotatable component of the transmission via which associated components of the transmission are connected to one another in a rotationally fixed manner or via which such a connection can be established upon actuation of one of the shift elements. The respective shaft can connect the components axially or radially, or even both axially and radially. For example, the respective shaft can also be in the form of an intermediate piece via which a respective component is connected radially, for example. The term “shaft” does not exclude the possibility that the components to be connected can be designed as a single piece. In particular, two or more shafts connected to one another in a rotationally fixed manner can be designed as a single piece.

[0008] A "switching element" is a switchable device that, when closed, connects two shafts or a shaft and a housing in a rotationally fixed manner, and, when opened, decouples the two shafts or the shaft and the housing. Two shafts can then rotate relative to each other.

[0009] According to one embodiment, the first shifting unit has three shift positions, namely two gear positions and a neutral position, the neutral position being arranged between the two gear positions, and the first sliding sleeve being displaceable into the respective shift position by means of a first actuator. In the neutral position, two shafts or a shaft and the stationary component are decoupled from one another via the first shifting unit, the first sliding sleeve then being in rotational engagement with a single shaft, in particular with the first ring gear shaft. The first sliding sleeve is designed to be positively engaged and has positively engaging claws which, in the respective gear position, interact positively with a respective corresponding claw toothing in order to establish a rotationally fixed connection between two shafts or a shaft and the stationary component.Therefore, the respective claw toothing with which the first sliding sleeve interacts in a positive-locking manner is to be understood as a shifting element. The first shifting unit preferably comprises unsynchronized claw clutches. Thus, the two shifting elements of the first shifting unit are designed as positive-locking shifting elements. Positive-locking shifting elements can increase the efficiency of the drive unit due to reduced drag losses. In particular, positive-locking shifting elements are more compact and have an optimized efficiency, offering a cost advantage over friction-locking shifting elements. The use of a single sliding sleeve and a single actuator for switching the third and fourth shifting elements further increases compactness.

[0010] The third and fourth shifting elements are designed as gear shifting elements and are thus configured for shifting gears. When the third shifting element is closed, i.e. in the first shifting position of the first sliding sleeve, the first ring gear shaft is connected in a rotationally fixed manner to the stationary component, with a first gear having a first ratio being active for the first electric machine. When the third and fourth shifting elements are open, i.e. in the second shifting position or neutral position of the first sliding sleeve, both electric machines are decoupled from the output. When the fourth shifting element is closed, i.e. in the third shifting position of the first sliding sleeve, the first ring gear shaft is connected in a rotationally fixed manner to the second carrier shaft and the output shaft, with a second gear having a second ratio being active for the first electric machine.

[0011] According to one embodiment, the second shifting unit further comprises a third shifting element. When the third shifting element is engaged, the first planetary gear set is locked, thereby engaging at least a third gear for the first electric motor. When the first planetary gear set is locked, the first planetary gear set rotates in a locked state, with only the gear ratio of the second planetary gear set being effective. For example, when the third shifting element is engaged, the first ring gear shaft is rotationally fixedly connected to the first carrier shaft and the second ring gear shaft.

[0012] According to one embodiment, the first shifting unit has five shift positions, namely three gear positions and two neutral positions, wherein the respective neutral position is arranged between two gear positions, wherein furthermore the first sliding sleeve can be moved into the respective shift position by means of a first actuator. In the respective neutral position, two shafts or a shaft and the stationary component are decoupled from one another via the first shifting unit, wherein the first sliding sleeve is then in rotational engagement with a single shaft, in particular with the first ring gear shaft. The first sliding sleeve is designed to be positively engaged and has positively engaging claws which, in the respective gear position, interact positively with a respective corresponding claw toothing in order to establish a rotationally fixed connection between two shafts or a shaft and the stationary component.Therefore, the respective claw toothing with which the first sliding sleeve interacts in a positive-locking manner is to be understood as a shifting element. The first shifting unit preferably comprises unsynchronized claw clutches. Thus, the three shifting elements of the first shifting unit are designed as positive-locking shifting elements. The use of a single sliding sleeve and a single actuator for switching the third, fourth, and fifth shifting elements further increases compactness.

[0013] When the third shift element is closed, i.e. in the first shift position of the first sliding sleeve, the first ring gear shaft is connected to the stationary component in a rotationally fixed manner, whereby a first gear with a first ratio is active for the first electric machine. When the third, fourth and fifth shift element is open, i.e. in the second or fourth shift position or one of the two neutral positions of the first sliding sleeve, both electric machines are decoupled from the output. When the fourth shift element is closed, i.e. in the third shift position of the first sliding sleeve, the first ring gear shaft is connected to the second carrier shaft and the output shaft in a rotationally fixed manner, whereby a second gear with a second ratio is active for the first electric machine.When the fifth shift element is closed, i.e., in the fifth shift position of the first sliding sleeve, the first planetary gear set is locked, with the first ring gear shaft preferably being rotationally fixedly connected to the first carrier shaft and the second ring gear shaft. This engages a third gear with a third ratio for the first electric motor.

[0014] According to one embodiment, the first and second shifting elements are combined to form a second shifting unit with a second sliding sleeve, the second shifting unit having three shift positions, namely two gear positions and a neutral position, the neutral position being arranged between the two gear positions, and the second sliding sleeve being displaceable into the respective shift position by means of a second actuator. In the neutral position, two shafts are decoupled from one another via the second shifting unit, the second sliding sleeve then being in rotational engagement with a single shaft. In particular, the second actuator displaces the second sliding sleeve into the respective shift position.The second sliding sleeve is designed to be positively engaged and has positive-locking claws that, in the respective gear position, interact positively with a corresponding claw toothing to establish a rotationally fixed connection between two shafts. Therefore, the respective claw toothing with which the second sliding sleeve interacts positively is to be understood as a shifting element. Preferably, the second shifting unit comprises unsynchronized claw clutches. Thus, all shifting elements of the second shifting unit are designed as positive-locking shifting elements. The use of a single sliding sleeve for switching the first and second shifting elements further increases compactness, requiring only a single actuator.

[0015] According to an alternative embodiment, the first shifting element can be actuated by a second actuator, and the second shifting element can be actuated by a third actuator. Thus, the manual transmission has a total of three actuators. Reference is made here to the embodiment according to Fig. 5.

[0016] For example, when only the second shifting element and the third shifting element are closed, a first gear can be set for the second electric machine. For example, when only the second shifting element and the fourth shifting element are closed, a second gear can be set for the second electric machine. For example, when only the first shifting element is closed, both electric machines are in speed superposition mode and support their torque against each other. This state is also known as the EDS state (electrodynamic shifting). In this EDS state, the torque ratio is fixed and the speed is variable. For example, when the first shifting element and the second shifting element are open, the second electric machine is decoupled from the manual transmission. The shift matrix according to Fig. 3b.

[0017] According to one embodiment, all switching elements of the drive unit are designed as claw switching elements, which can be synchronized by means of the two electrical machines.

[0018] According to one embodiment, the two electric machines are arranged axially parallel to one another and to the manual transmission, wherein the first electric machine is connected to the drive shaft via a first spur gear stage and a second spur gear stage, wherein the second electric machine can be connected to the first ring gear shaft or to the drive shaft via a third spur gear stage and a fourth spur gear stage, wherein the first and the second switching element, in particular the second switching unit, are arranged at least partially radially nested with the first spur gear stage and the third spur gear stage. In particular, the first spur gear stage has a first spur gear and a second spur gear which are in meshing engagement with one another. Furthermore, the second spur gear stage has a third spur gear and a fourth spur gear which are in meshing engagement with one another.The first spur gear is, for example, rotationally fixedly connected to a rotor shaft of the first electric machine, wherein the second and third spur gears are rotationally fixedly connected, wherein the fourth spur gear is rotationally fixedly connected to the drive shaft. In particular, the third spur gear stage has a fifth spur gear and a sixth spur gear, which mesh with one another. Furthermore, the fourth spur gear stage has a seventh spur gear and an eighth spur gear, which mesh with one another. The fifth spur gear is, for example, rotationally fixedly connected to a rotor shaft of the second electric machine, wherein the sixth and seventh spur gears are rotationally fixedly connected, wherein the eighth spur gear is either rotationally fixedly connectable to the first ring gear shaft via the first switching element or rotationally fixedly connectable to the drive shaft and the first sun gear shaft via the second switching element.In particular, the first spur gear stage and the third spur gear stage are arranged radially nested on an outer circumference of the second switching unit in order to save axial installation space.

[0019] As a result, the second switching unit with the first and second switching elements, the first spur gear stage and the third spur gear stage are at least partially located in the same axial installation space plane.

[0020] According to an alternative embodiment, the two electric machines are arranged coaxially with the manual transmission, with a rotor of the first electric machine being rotationally fixedly connected to the drive shaft, and a rotor of the second electric machine being rotationally fixedly connected either to the first ring gear shaft or to the drive shaft and the first sun gear shaft, depending on whether the first or second switching element is closed. When the first and second switching elements are open, the second electric machine is decoupled from the drivetrain.

[0021] According to one embodiment, a differential with a differential input shaft, a first differential output shaft, and a second differential output shaft is arranged coaxially with the manual transmission, the first differential output shaft being guided axially through the manual transmission, and the differential input shaft being connected in a rotationally fixed manner to the output shaft. For example, the differential is designed as a ball or bevel gear differential. A differential designed as a ball or bevel gear differential has two wheel-side output elements, in particular a first output gear and a second output gear. The two output gears each mesh with a compensating element. The compensating elements are mounted in a differential carrier for rotation about their own axis. The respective output gear is connected in a rotationally fixed manner to the respective differential output shaft.The differential is driven via the differential cage, which serves as the differential input shaft. Alternative differential designs are also conceivable, such as a spur gear differential or planetary differential. The drive power fed into the differential via the differential input shaft is distributed in a known manner between the two differential output shafts and transmitted to the drive wheels of the axle. The differential output shafts are designed to be connected to the vehicle's drive wheels in a drive-effective manner. The respective differential output shaft can be connected to the corresponding vehicle wheel directly or indirectly via a downstream fixed gear, a joint, a propeller shaft, and / or a wheel hub.

[0022] A vehicle according to the invention comprises a drive unit according to the invention. The above definitions as well as statements regarding technical effects, advantages, and advantageous embodiments of the drive unit according to the invention also apply mutatis mutandis to the vehicle according to the invention.

[0023] Advantageous embodiments of the invention, which are explained below, are illustrated in the drawings, wherein identical or similar elements are provided with the same reference numerals. They show: Fig. 1 is a highly abstracted schematic view of a vehicle with a drive axle having a drive unit according to the invention; Fig. 2 a highly abstracted schematic view of a drive unit according to the invention according to a first embodiment; Fig. 3a a highly abstracted schematic view of a drive unit according to the invention according to a second embodiment; Fig. 3b a switching matrix for the drive unit according to Fig. 3a; Fig. 4 a highly abstracted schematic view of a drive unit according to the invention according to a third embodiment and Fig. 5 a highly abstracted schematic view of a drive unit according to the invention according to a fourth embodiment.

[0024] Fig. 1 shows a vehicle 100 with a first axle 101 with two vehicle wheels R1, R2 and a second axle 102 with two vehicle wheels R3, R4. In the present case, the first axle 101 is designed as the rear drive axle of the vehicle 100 and is equipped with a drive unit according to the invention. The drive unit comprises a first and a second electric machine EM1, EM2, each of which is designed to generate drive power, a manual transmission SG with two gears, and a differential DG. Thus, the vehicle 100 is designed as an electric vehicle, i.e., as an electrically driven vehicle. The drive unit is arranged transversely to the vehicle's longitudinal direction and is drivingly connected to the vehicle wheels R1, R2 of the first axle 101. A detailed design of this drive unit is shown in Fig. 2. Alternatively, the differential DG can be arranged axially parallel to the manual transmission and / or transversely to the vehicle's longitudinal direction. In the present case, no further drive unit is arranged on the second axle 102, i.e., on the front axle of the vehicle 100, thereby saving costs, weight, and installation space. Alternatively, the drive unit can be arranged on the front axle of the vehicle 100 instead of on the rear axle. To implement an all-wheel drive system, a further drive unit can be arranged on the second axle 102 and be drivingly connected to the vehicle wheels R3, R4 of this axle 102.

[0025] Fig. 2 shows the drive unit according to a first embodiment. The drive unit comprises an input shaft An for connecting the first electric machine EM1 to the manual transmission SG and an output shaft Ab for connecting the manual transmission SG to the differential DG. The differential DG has a differential input shaft D1 and two differential output shafts D2, D3, wherein the differential DG is arranged coaxially to the manual transmission SG and the first differential output shaft D2 is guided axially through the manual transmission SG, whereby the drive unit is particularly compact. In particular, the input shaft An and the output shaft Ab are designed as hollow shafts. The differential input shaft D1 is connected to the output shaft Ab in a rotationally fixed manner. The differential DG is designed as a ball or bevel gear differential. The differential input shaft D1 is designed as a differential carrier.The differential DG, designed as a ball or bevel gear differential, has two wheel-side output elements, specifically a first output gear and a second output gear. The two output gears each mesh with a compensating element. The compensating elements are mounted in the differential carrier so they can rotate about their own axes. The respective output gear is connected in a rotationally fixed manner to the respective differential output shaft D2, D3. Thus, the differential DG is driven via the differential carrier, which is connected in a rotationally fixed manner to the output shaft Ab. Arrows on the differential output shafts D2, D3 indicate a connection to a respective vehicle wheel of this vehicle axle.

[0026] The manual transmission SG has a first planetary gear set PS1, a second planetary gear set PS2 and five shift elements E, D, A, B, C. The two planetary gear sets PS1, PS2 are arranged axially adjacent to one another to save installation space and increase compactness. The first planetary gear set PS1 comprises three shafts, namely a first sun gear shaft SO1, a first ring gear shaft HR1 and a first carrier shaft ST1. The first carrier shaft ST1 carries a plurality of planet gears that mesh with the first sun gear shaft SO1 and the first ring gear shaft HR1. The second planetary gear set PS2 also comprises three shafts, namely a second sun gear shaft SO2, a second ring gear shaft HR2 and a second carrier shaft ST2. The second carrier shaft ST2 carries a plurality of planet gears that mesh with the second sun gear shaft SO2 and the second ring gear shaft HR2. The first sun gear shaft SO1 is connected to the input shaft An in a rotationally fixed manner.The first carrier shaft ST1 is non-rotatably connected to the second ring gear shaft HR2. The second carrier shaft ST2 is non-rotatably connected to the output shaft Ab. The second sun gear shaft SO2 is non-rotatably connected to a stationary component formed as a housing G.

[0027] A third shifting element A, a fourth shifting element B and a fifth shifting element C are combined to form a first shifting unit with five shift positions, wherein the first shifting unit has a first sliding sleeve SM1 which can be moved into the respective shift position by means of a first actuator AK1. The first shifting unit is arranged radially nested on a circumference of the second planetary gear set PS2 and is thus arranged at least partially in a common axial plane with the second planetary gear set PS2, thereby saving axial installation space. A first shifting element D and a second shifting element E are combined to form a second shifting unit with three shift positions, wherein the second shifting unit has a second sliding sleeve SM2 which can be moved into the respective shift position by means of a second actuator AK2.

[0028] Regardless of the switching position of the first and second switching elements D, E, when the third switching element A is closed, the first ring gear shaft HR1 is connected in a rotationally fixed manner to the stationary component designed as a housing G, whereby a first gear is engaged for the first electric machine EM1. Likewise, regardless of the switching position of the first and second switching elements D, E, when the fourth switching element B is closed, the first ring gear shaft HR1 is connected in a rotationally fixed manner to the second carrier shaft ST2 and the output shaft Ab, whereby a second gear is engaged for the first electric machine EM1.Also independent of the switching position of the first and second switching elements D, E, in a closed state of the fifth switching element C, the first planetary gear set PS1 is blocked, wherein in this case the first ring gear shaft HR1, the first carrier shaft ST1 and the second ring gear shaft HR2 are connected in a rotationally fixed manner, whereby a third gear is engaged for the first electric machine EM1.

[0029] The first gear for the first electric machine EM1 is engaged when the first sliding sleeve SM1 is in a first gear position, i.e., in a first switching position. The third switching element A, in an actuated or closed state, i.e., in the first switching position of the first sliding sleeve SM1, connects the first ring gear shaft HR1 to the stationary component to engage the first gear for the first electric machine EM1.

[0030] The first gear for the first electric machine EM1 is disengaged by axially shifting the first sliding sleeve SM1 into a first neutral position, i.e., into a second switching position. In the second switching position of the first sliding sleeve SM1, the first sliding sleeve SM1 is only in rotational engagement with the first ring gear shaft HR1. In this neutral position, the switching elements A, B, C are open. In this case, Fig. 2 shows this second switching position of the first sliding sleeve SM1.

[0031] The second gear for the first electric motor EM1 is engaged by axially shifting the first sliding sleeve SM1 into a second gear position, i.e., a third shift position. The fourth shift element B, in an actuated or closed state, i.e., in the third shift position of the first sliding sleeve SM1, connects the first ring gear shaft HR1 with the second carrier shaft ST2 and the output shaft Ab to engage the second gear for the first electric motor EM1.

[0032] Second gear for the first electric motor EM1 is disengaged by axially shifting the first sliding sleeve SM1 into a second neutral position, i.e., a fourth shift position. In the fourth shift position of the first sliding sleeve SM1, the first sliding sleeve SM1 is only in rotational engagement with the first ring gear shaft HR1. In this neutral position, the shift elements A, B, and C are open.

[0033] The third gear for the first electric machine EM1 is engaged by axially shifting the first sliding sleeve SM1 into a third gear position, i.e., a fifth shift position. The fifth shift element B, in an actuated or closed state, i.e., in the fifth shift position of the first sliding sleeve SM1, connects the first ring gear shaft HR1 with the second ring gear shaft HR2 and the first carrier shaft ST1 to engage the third gear for the first electric machine EM1.

[0034] In a first switching position of the second sliding sleeve SM2, the first switching element D is closed, whereby the second electric machine EM2 is drivingly connected to the first ring gear shaft HR1. In a second switching position of the second sliding sleeve SM2, both switching elements D, E are opened, whereby the second electric machine EM2 is thereby decoupled from the manual transmission SG. In the present case, Fig. 2 shows this second switching position of the second sliding sleeve SM2. In a third switching position of the second sliding sleeve SM2, the second switching element E is closed and the second electric machine EM2 is drivingly connected to the drive shaft An.

[0035] The first electric machine EM1 is connected to the drive shaft An via a first spur gear stage SR1 and a second spur gear stage SR2. In this case, the first spur gear stage SR1 has a first spur gear S1 and a second spur gear S2, which mesh with each other. Furthermore, the second spur gear stage SR2 has a third spur gear S3 and a fourth spur gear S4, which mesh with each other. In this case, the first spur gear S1 is connected in a rotationally fixed manner to a rotor shaft of the first electric machine EM1, wherein the second and third spur gears S2, S3 are connected in a rotationally fixed manner, wherein the fourth spur gear S4 is connected in a rotationally fixed manner to the drive shaft An.

[0036] The second electric machine EM2 can be connected to the first carrier shaft HR1 or to the drive shaft An via the third spur gear stage SR3 and the fourth spur gear stage SR4. Furthermore, the third spur gear stage SR3 has a fifth spur gear S5 and a sixth spur gear S6, which mesh with each other. The fourth spur gear stage SR4 has a seventh spur gear S7 and an eighth spur gear S8, which mesh with each other. The fifth spur gear S5 is here connected in a rotationally fixed manner to a rotor shaft of the second electric machine EM2, wherein the sixth and seventh spur gears S6, S7 are connected in a rotationally fixed manner, wherein the eighth spur gear S8 can be connected in a rotationally fixed manner to the first ring gear shaft HR1 or to the drive shaft An via the second switching unit. When the first switching element D is closed, the eighth spur gear S8 is connected in a rotationally fixed manner to the first ring gear shaft HR1.When the second shift element E is closed, the eighth spur gear S8 is connected to the drive shaft An and the first sun gear SO1, which is connected to it in a rotationally fixed manner. The second shift unit is arranged radially nested with the first spur gear stage SR1 and the third spur gear stage SR3 to save axial space.

[0037] The input shaft An, the output shaft Ab, the manual transmission SG and the differential DG are arranged on a common axis of rotation R and are therefore coaxial with one another. The two electric machines EM1, EM2 are arranged axially parallel to the axis of rotation R. According to an axial sequence, the fourth spur gear stage SR4 is arranged axially adjacent to the second spur gear stage SR2, wherein the second switching unit, which is in a common axial plane with the first and third spur gear stages SR1, SR3, is arranged axially adjacent to the fourth spur gear stage SR4, wherein the first planetary gear set PS1 is arranged axially adjacent to the second switching unit, wherein the second planetary gear set PS2 is arranged axially adjacent to the first planetary gear set PS1, wherein the differential DG is arranged axially adjacent to the second planetary gear set PS2.

[0038] Fig. Figure 3a shows a drive unit according to a second embodiment. The drive unit comprises an input shaft An for connecting the first electric motor EM1 to the manual transmission SG and an output shaft Ab for connecting the manual transmission SG to a vehicle wheel or to a differential, which is illustrated in simplified form by the arrow on the output shaft Ab.

[0039] The manual transmission SG has a first planetary gear set PS1, a second planetary gear set PS2 and four shift elements E, D, A, B. The two planetary gear sets PS1, PS2 are arranged axially adjacent to one another to save installation space and increase compactness. The first planetary gear set PS1 comprises three shafts, namely a first sun gear shaft SO1, a first ring gear shaft HR1 and a first carrier shaft ST1. The first carrier shaft ST1 carries a plurality of planet gears that mesh with the first sun gear shaft SO1 and the first ring gear shaft HR1. The second planetary gear set PS2 also comprises three shafts, namely a second sun gear shaft SO2, a second ring gear shaft HR2 and a second carrier shaft ST2. The second carrier shaft ST2 carries a plurality of planet gears that mesh with the second sun gear shaft SO2 and the second ring gear shaft HR2. The first sun gear shaft SO1 is connected to the input shaft An in a rotationally fixed manner.The first carrier shaft ST1 is non-rotatably connected to the second ring gear shaft HR2. The second carrier shaft ST2 is non-rotatably connected to the output shaft Ab. The second sun gear shaft SO2 is non-rotatably connected to a stationary component formed as a housing G.

[0040] A third shifting element A and a fourth shifting element B are combined to form a first shifting unit with three shift positions, the first shifting unit having a first sliding sleeve SM1 which can be moved into the respective shift position by means of a first actuator AK1. The first shifting unit is arranged radially nested on a circumference of the second planetary gear set PS2 and is thus arranged at least partially in a common axial plane with the second planetary gear set PS2, thereby saving axial installation space. A first shifting element D and a second shifting element E are combined to form a second shifting unit with three shift positions, the second shifting unit having a second sliding sleeve SM2 which can be moved into the respective shift position by means of a second actuator AK2.

[0041] Regardless of the switching position of the first and second switching elements D, E, when the third switching element A is closed, the first ring gear shaft HR1 is connected in a rotationally fixed manner to the stationary component designed as a housing G, whereby a first gear is engaged for the first electric machine EM1. Likewise, regardless of the switching position of the first and second switching elements D, E, when the fourth switching element B is closed, the first ring gear shaft HR1 is connected in a rotationally fixed manner to the second carrier shaft ST2 and the output shaft Ab, whereby a second gear is engaged for the first electric machine EM1.

[0042] The first gear for the first electric machine EM1 is engaged when the first sliding sleeve SM1 is in a first gear position, i.e., in a first switching position. The third switching element A, in an actuated or closed state, i.e., in the first switching position of the first sliding sleeve SM1, connects the first ring gear shaft HR1 to the stationary component to engage the first gear for the first electric machine EM1.

[0043] The first gear for the first electric machine EM1 is disengaged by axially shifting the first sliding sleeve SM1 into a first neutral position, i.e., into a second switching position. In the second switching position of the first sliding sleeve SM1, the first sliding sleeve SM1 is only in rotational engagement with the first ring gear shaft HR1. In this neutral position, the switching elements A, B are open. In this case, Fig. 3a shows this second switching position of the first sliding sleeve SM1.

[0044] The second gear for the first electric motor EM1 is engaged by axially shifting the first sliding sleeve SM1 into a second gear position, i.e., a third shift position. The fourth shift element B, in an actuated or closed state, i.e., in the third shift position of the first sliding sleeve SM1, connects the first ring gear shaft HR1 with the second carrier shaft ST2 and the output shaft Ab to engage the second gear for the first electric motor EM1.

[0045] In a first switching position of the second sliding sleeve SM2, the first switching element D is closed, whereby the second electric machine EM2 is drivingly connected to the first ring gear shaft HR1. In a second switching position of the second sliding sleeve SM2, both switching elements D, E are opened, whereby the second electric machine EM2 is thereby decoupled from the manual transmission SG. In the present case, Fig. 3a shows this second switching position of the second sliding sleeve SM2. In a third switching position of the second sliding sleeve SM2, the second switching element E is closed and the second electric machine EM2 is drivingly connected to the drive shaft An.

[0046] The first electric machine EM1 has a first rotor EMR1 and a first stator EMS1. The second electric machine EM2 has a second rotor EMR2 and a second stator EMS2. The first rotor EMR1 is rotationally fixedly connected to the drive shaft An. The second rotor EMR2 can be rotationally fixedly connected to the first ring gear shaft HR1 or to the drive shaft An and the first sun gear shaft SO1, depending on whether the first or second switching element D, E is closed. When the first and second switching elements D, E are open, the second electric machine EM2 is decoupled from the drive train, which, for example, reduces losses due to rotating bearings and electrical losses, for example during partial load operation. The second switching unit is arranged at least partially radially inside the second electric machine EM2 in order to save axial installation space.

[0047] The two electric machines EM1, EM2, the input shaft An, the output shaft Ab and the manual transmission SG are arranged on a common rotation axis R and are thus coaxial with each other. Fig. 3a and Fig. 4 and Fig. 5 shows only the "upper" half of the respective drive unit, with the "lower" half (not shown) being symmetrical to the "upper" half. The lower half of the drive unit is created by mirroring it about the rotation axis R.

[0048] Fig. 3b shows a switching matrix for the drive unit according to Fig. 3a. In the columns of the switching matrix, a respective state of the drive unit, the respective gear for the first electric machine EM1, the respective gear for the second electric machine EM2 and the four switching elements A, B, D, E of the drive unit are shown according to Fig. 3a. Depending on the switching position of the four switching elements A, B, D, and E, a total of eight states can be realized for the drive unit.

[0049] In a first state of the drive unit, the second switching element E and the third switching element A are closed, while the first switching element D and the fourth switching element B are open. As a result, a first gear is engaged for the first electric machine EM1 as well as for the second electric machine EM2.

[0050] In a second state of the drive unit, the second switching element E and the fourth switching element B are closed, while the first switching element D and the third switching element A are open. As a result, a second gear is engaged for the first electric machine EM1 as well as for the second electric machine EM2.

[0051] In a third state of the drive unit, the first switching element D and the third switching element A are closed, while the second switching element E and the fourth switching element B are open. As a result, a first gear is engaged for the first electric machine EM1, while the second electric machine EM2 is in an intermediate state, i.e., no specific gear is engaged for the second electric machine EM2.

[0052] In a fourth state of the drive unit, the first switching element D and the fourth switching element B are closed, while the second switching element E and the third switching element A are open. As a result, a second gear is engaged for the first electric machine EM1, while the second electric machine EM2 is in an intermediate state, i.e., no specific gear is engaged for the second electric machine EM2.

[0053] In a fifth state of the drive unit, only the first switching element D is closed, while the second switching element E, the third switching element A, and the fourth switching element B are open. This creates an electrodynamic shift (EDS) for both electric machines EM1, EM2. In other words, the first and second electric machines EM1, EM2 are in speed-overlapping operation and mutually support their torque, with the torque ratio being fixed and the speed being variable.

[0054] In a sixth state of the drive unit, only the third switching element A is closed, while the first switching element D, the second switching element E, and the fourth switching element B are open. As a result, a first gear is engaged for the first electric machine EM1, while the second electric machine EM2 is decoupled from the drive train.

[0055] In a seventh state of the drive unit, only the fourth switching element B is closed, while the first switching element D, the second switching element E, and the third switching element A are open. As a result, a second gear is engaged for the first electric machine EM1, while the second electric machine EM2 is decoupled from the drive train.

[0056] In an eighth state of the drive unit, only the second switching element E is closed, while the first switching element D, the third switching element A, and the fourth switching element B are open. This decouples both electric motors EM1, EM2 from the drive train. Likewise, all switching elements A, B, D, and E can be open to decouple both electric motors EM1, EM2 from the drive train.

[0057] As an example, the gearshift sequence is described with a power shift from the first gear of the first electric machine EM1 to the second gear of the first electric machine EM1. In the initial state, i.e. the first state, both electric machines EM1, EM2 are in first gear and can jointly contribute drive power to the drivetrain. The second electric machine EM2 is recoupled via the first switching unit, with the second switching element E being opened and the first switching element D being closed. This reaches the third state. The second electric machine EM2 synchronizes the switching elements E and D. While the second electric machine EM2 is being recoupled, the first electric machine EM1 can support the tractive force. The second electric machine EM2 is braked hard.The third shift element A is relieved of load by the appropriate torque ratio of the first electric machine EM1 to the second electric machine EM2 in accordance with the stationary gear ratio of the first planetary gear set PS1 and is then opened, thereby reaching the fifth state according to the shift matrix. In the fifth state, the two electric machines EM1, EM2 are in the EDL state, which implements the power shift from first to second gear. In principle, longer driving periods in the EDL state are also possible, in which case the two electric machines EM1, EM2 can, for example, have the same speed. This state is therefore also suitable for higher driving speeds, as the speed ratio of input to output corresponds to a gear with a lower gear ratio than second gear when the first planetary gear set PS1 rotates in unison at the same speed of the two electric machines EM1, EM2.The speed of the first electric machine EM1 is synchronized to the level of the target gear, i.e. second gear, and then the fourth shift element B is closed, thereby reaching the fourth state. The second electric machine EM2 is then torsionally fixedly connected to the output shaft Ab. The second electric machine EM2 is recoupled via the second shift unit, with the first shift element D being opened and the second shift element E being closed. The second state is reached, with the second electric machine synchronizing the shift elements of the second shift unit. While the second electric machine EM2 is being recoupled, the first electric machine EM1 can support the tractive force. In the second state, both electric machines EM1, EM2 are in second gear and can jointly contribute drive power to the drivetrain.

[0058] Fig. 4 shows a third embodiment of the drive unit according to the invention. The drive unit according to Fig. 4 essentially corresponds to the drive unit according to Fig. 3a, wherein one difference between these two embodiments lies in the design of the first shifting unit. In the present case, the drive unit further comprises a fifth shifting element C. The third shifting element A, the fourth shifting element B, and the fifth shifting element C together form the first shifting unit. With the fifth shifting element C, a third gear designed as a direct gear with a third ratio can be shifted. In the closed state, the fifth shifting element C connects the first ring gear shaft HR1 with the first carrier shaft ST1 and the second ring gear shaft HR2.

[0059] The first shift unit has five shift positions and a single axially movable first sliding sleeve SM1, with which the five shift positions are realized. The first sliding sleeve SM1 has claw shift elements and can be axially moved into the respective shift position by means of a single first actuator AK1. Thus, all five shift positions of the first shift unit are arranged linearly and consist of three gear positions and two neutral positions, with a neutral position located between each two gear positions. The three gears are shifted one after the other or sequentially by moving the first sliding sleeve SM1 in an axial direction, beyond the neutral position. This not only saves weight and components, but also costs, installation space, and assembly effort.The first three switching positions of the first sliding sleeve SM1 according to this third embodiment of the manual transmission SG correspond exactly to the first three switching positions of the first sliding sleeve SM1 according to the second embodiment of the manual transmission SG.

[0060] Second gear is disengaged by axially shifting the first sliding sleeve SM1 into a second neutral position, i.e., the fourth shift position. In the second neutral position, the first sliding sleeve SM1 is only in rotational engagement with the first ring gear shaft. In this neutral position, all three shift elements A, B, and C are open. Third gear is engaged by axially shifting the first sliding sleeve SM1 into a third gear position, i.e., a fifth shift position. In the fifth shift position of the first sliding sleeve SM1, the third shift element C connects the first ring gear shaft HR1 with the first carrier shaft ST1 and the second ring gear shaft HR2 in order to block the first planetary gear set PS1 and shift the third gear for the first electric machine EM1.

[0061] The shift from second gear to third gear for the first electric machine EM1 can be performed as an electrodynamic load shift (EDS). In the initial state, both electric machines EM1 and EM2 are in second gear (state 2 in the shift matrix according to Fig. 3b). The second electrical machine EM2 is recoupled via the first switching unit, whereby the second switching element E is opened and the first switching element D is closed. The fourth state in the switching matrix according to Fig. 3b is achieved in this way. During the recoupling of the second electric machine EM2, the first electric machine EM1 can support the traction force. The second electric machine EM2 is connected to the output via the first switching element D and the fourth switching element B. The fourth switching element B is relieved by the appropriate torque ratio of the first electric machine EM1 to the second electric machine EM2 and then opened, thereby achieving the fifth state according to the switching matrix according to Fig. 3b is achieved. In the fifth state, the two electric machines EM1, EM2 are in the EDL state, whereby the power shift from second to third gear is realized. The speed of the first electric machine EM1 is synchronized to the level of the target gear, i.e., third gear, after which the fifth shift element C is closed. The two electric machines EM1, EM2 then have the same speed, since the first planetary gear set PS1 rotates in unison, with the two electric machines EM1, EM2 being in third gear. The second electric machine EM2 can optionally be recoupled from the first shift element D to the second shift element E, whereby the speed of the second electric machine EM2 does not change. This state is useful, for example, when a traction-interrupted shift in second gear (state 2 in the shift matrix according to Fig. 3b), in which the second switching element E remains closed. The fifth switching element C is opened, synchronizing the second gear and closing the fourth switching element B. Otherwise, the embodiment according to Fig. 4 the embodiment according to Fig. 3a, to which reference is made.

[0062] Fig. Figure 5 shows a fourth embodiment of the drive unit according to the invention. The drive unit according to Fig. 5 essentially corresponds to the drive unit according to Fig. 3a, wherein a difference between these two embodiments lies in the design of the first and second shifting elements D, E. In the present case, the drive unit does not have a second shifting unit. Thus, the first and second shifting elements D, E are designed as individual shifting elements and thus are not combined to form a second shifting unit. The first shifting element D can be actuated by means of a second actuator AK2, wherein the second shifting element E can be actuated by means of a third actuator AK3. As a result, the first shifting element D and the second shifting element E can be closed simultaneously, wherein the first planetary gear set PS1 is then blocked and thus the third gear is engaged, wherein this third gear corresponds to the third gear according to Fig. 4. This therefore represents a blocking variant of the fifth switching element C. Here, too, an electrodynamic load switching is possible. From the fifth state according to Fig. 3b (only the first switching element D is closed), the second switching element E is additionally closed to enter the third gear for the first electric machine EM1. Thus, a third mechanical gear is enabled with the four switching elements A, B, D, E. Otherwise, the embodiment corresponds to Fig. 5 the embodiment according to Fig. 3a, to which reference is made. Reference symbol 100 vehicles 101 first axis 102 second axis R1 vehicle wheel R2 vehicle wheel R3 vehicle wheel R4 vehicle wheel On drive shaft From output shaft SG manual transmission EM1 first electric machine EMS1 first stator EMR1 first rotor EM2 second electric machine EMS1 second stator EMR1 second rotor SR1 first spur gear stage SR2 second spur gear stage SR3 third spur gear stage SR4 fourth spur gear stage S1 first spur gear S2 second spur gear S3 third spur gear S4 fourth spur gear S5 fifth spur gear S6 sixth spur gear S7 seventh spur gear S8 eighth spur gear PS1 first planetary gear set SO1 first solar wave HO1 first ring gear shaft ST1 first bridge wave PS2 second planetary gear set SO2 second solar wave HO2 second ring gear shaft ST2 second web wave AK1 first actuator AK2 second actuator AK3 third actuator SM1 first sliding sleeve SM2 second sliding sleeve G Housing R rotation axis DG Differential D1 differential input shaft D2 first differential output shaft D3 second differential output shaft D first switching element E second switching element A third switching element B fourth switching element C fifth switching element QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2013 214 238 A1

[0002] DE 10 2019 218 413 A1

[0003]

Claims

[1] Drive unit for a vehicle (100), comprising a first electric machine (EM1), a second electric machine (EM2) and a manual transmission (SG) with • a first planetary gear set (PS1) comprising a first sun shaft (SO1), a first ring gear shaft (HR1) and a first carrier shaft (ST1), • a second planetary gear set (PS2) comprising a second sun gear shaft (SO2), a second ring gear shaft (HR2) and a second carrier shaft (ST2), • a first switching element (D), a second switching element (E) and a first positive switching unit with a third switching element (A), a fourth switching element (B) and a first sliding sleeve (SM1), • wherein the manual transmission (SG) is connected to the first electric machine (EM1) via a drive shaft (An), • wherein the first sun shaft (SO1) is connected in a rotationally fixed manner to the drive shaft (An), wherein the first carrier shaft (ST1) is connected in a rotationally fixed manner to the second ring gear shaft (HR2), wherein the second carrier shaft (ST2) is connected in a rotationally fixed manner to an output shaft (Ab), wherein the second sun shaft (SO2) is connected in a rotationally fixed manner to a stationary component, • wherein in a closed state of the first switching element (D), the second electrical machine (EM2) is drivingly connected to the first ring gear shaft (HR1), • wherein in a closed state of the second switching element (E), the second electric machine (EM2) is drivingly connected to the drive shaft (An) and the first sun shaft (SO1), • wherein in a closed state of the third switching element (A), the first ring gear shaft (HR1) is connected in a rotationally fixed manner to the stationary component, whereby at least a first gear for the first electric machine (EM1) is engaged, • wherein in a closed state of the fourth switching element (B), the first ring gear shaft (HR1) is connected in a rotationally fixed manner to the second carrier shaft (ST2) and the output shaft (Ab), whereby at least a second gear for the first electric machine (EM1) is engaged. [2] Drive unit according to claim 1, wherein the first switching unit has three switching positions, namely two gear positions and a neutral position, wherein the neutral position is arranged between the two gear positions, wherein furthermore the first sliding sleeve (SM1) is displaceable into the respective switching position by means of a first actuator (AK1). [3] Manual transmission (SG) according to claim 1, wherein the second switching unit further comprises a third switching element (C), wherein in the closed state of the third switching element (C) the first planetary gear set (PS1) is blocked, whereby at least a third gear is engaged for the first electric machine (EM1). [4] Manual transmission (SG) according to claim 3, wherein in the closed state of the third shift element (C) the first ring gear shaft (HR1) is connected in a rotationally fixed manner to the first carrier shaft (ST1) and the second ring gear shaft (HR2). [5] Drive unit according to claim 3 or 4, wherein the first switching unit has five switching positions, namely three gear positions and two neutral positions, wherein the respective neutral position is arranged between two gear positions, wherein furthermore the first sliding sleeve (SM1) is displaceable into the respective switching position by means of a first actuator (AK1). [6] Drive unit according to one of the preceding claims, wherein the first and the second switching element (D, E) are combined to form a second switching unit with a second sliding sleeve (SM2), wherein the second switching unit has three switching positions, namely two gear positions and a neutral position, wherein the neutral position is arranged between the two gear positions, wherein furthermore the second sliding sleeve (SM2) is displaceable into the respective switching position by means of a second actuator (AK2). [7] Drive unit according to one of claims 1 to 5, wherein the first switching element (D) is operable by means of a second actuator (AK2), wherein the second switching element (E) is operable by means of a third actuator (AK3). [8] Drive unit according to one of the preceding claims, wherein the two electric machines (EM1, EM2) are arranged axially parallel to each other and to the gearbox (SG), • wherein the first electric machine (EM1) is connected to the drive shaft (An) via a first spur gear stage (SR1) and a second spur gear stage (SR2), • wherein the second electric machine (EM2) can be connected to the first ring gear shaft (HR1) or to the drive shaft (An) via a third spur gear stage (SR3) and a fourth spur gear stage (SR4), • wherein the first and the second switching element (D, E) are arranged at least partially radially nested with the first spur gear stage (SR1) and the third spur gear stage (SR3). [9] Drive unit according to one of claims 1 to 7, wherein the two electric machines (EM1, EM2) are arranged coaxially to the gearbox (SG), wherein a first rotor (EMR1) of the first electric machine (EM1) is connected in a rotationally fixed manner to the drive shaft (An), wherein a second rotor (EMR2) of the second electric machine (EM2) is connectable in a rotationally fixed manner to the first ring gear shaft (HR1) or to the drive shaft (An) and the first sun gear shaft (SO1). [10] Drive unit according to one of the preceding claims, wherein a differential (DG) with a differential input shaft (D1), a first differential output shaft (D2) and a second differential output shaft (D3) is arranged coaxially to the manual transmission (SG), wherein the first differential output shaft (D2) is guided axially through the manual transmission (SG), wherein the differential input shaft (D1) is connected to the output shaft (Ab) in a rotationally fixed manner. [11] Drive unit according to one of the preceding claims, wherein in the closed state of only the second switching element (E) and the third switching element (A) a first gear for the second electric machine (EM2) can be set. [12] Drive unit according to one of the preceding claims, wherein in the closed state of only the second switching element (E) and the fourth switching element (B) a second gear for the second electric machine (EM2) can be set. [13] Drive unit according to one of the preceding claims, wherein both electric machines (EM1, EM2) are in a speed superposition operation in the closed state of only the first switching element (D) and mutually support their torque. [14] Drive unit according to one of the preceding claims, wherein in the open state of the first switching element (D) and the second switching element (E), the second electric machine (EM2) is decoupled from the manual transmission (SG). [15] Vehicle (100) comprising at least one drive unit according to one of the preceding claims.

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