Hybrid transmission and motor vehicle with a hybrid transmission

Abstract

Hybrid transmission (1) for a motor vehicle (100), comprising • a first transmission input shaft (2) for connecting a crankshaft (3.1) of an internal combustion engine (3), • a second transmission input shaft (4) for connecting a rotor shaft (5.1) of a first electric machine (5), • a first planetary gear set (P1) with a sun gear (P11), a ring gear (P12) and a planet carrier (P13), • a second planetary gear set (P2) with a sun gear (P21), a ring gear (P22) and a planetary carrier (P23), wherein the two planetary gear sets (P1, P2) and the two transmission input shafts (2, 4) are arranged coaxially to one another, • a main output shaft (10) arranged coaxially to the two planetary gear sets (P1, P2), • at least a first shifting element (A), a second shifting element (B), a third shifting element (C), a fourth shifting element (D) and a fifth shifting element (E), wherein all five shifting elements (A, B, C, D, E) are arranged coaxially to the two planetary gear sets (P1, P2), and wherein all five shifting elements (A, B, C, D, E) are designed as positive shifting elements and at least three of the five shifting elements (A, B, C, D, E) are arranged axially between the two planetary gear sets (P1, P2), characterized in that there is also a differential (6) which is arranged coaxially to the two planetary gear sets (P1, P2) and has a first and second side shaft (6.1, 6.2), wherein the main output shaft (10) is at least indirectly connected to the differential (6), and wherein the side shafts (6.1, 6.2) of the differential (6) are arranged to connect a respective wheel of the motor vehicle (100), and wherein, according to an axial sequence, first the differential (6), adjacent thereto the second planetary gear set (P2), adjacent thereto the connection of the first electric machine (5), adjacent thereto the fifth shifting element (E), adjacent thereto the third shifting element (C), adjacent thereto the fourth shifting element (D), adjacent thereto the first planetary gear set (P1), adjacent thereto the connection of the internal combustion engine (3), adjacent thereto the second shifting element (B), and adjacent thereto the first shifting element (A) are arranged.

Description

[0001] The invention relates to a hybrid transmission for a motor vehicle, comprising two transmission input shafts for connecting a respective drive motor, two planetary gear sets, a main output shaft, and at least five shift elements. Furthermore, the invention also relates to a motor vehicle with such a hybrid transmission.

[0002] For example, DE 10 2013 215 114 A1 discloses a hybrid drive of a motor vehicle, which has an internal combustion engine with a drive shaft, an electric machine with a rotor that can be operated as a motor and as a generator, an automated manual transmission designed in countershaft design with an input shaft and at least one output shaft, and a superposition transmission designed in planetary design with two input elements and one output element.In this hybrid drive it is provided that the superposition gear is arranged coaxially above a free end of the output shaft, and that the first input element of the superposition gear is connected in a rotationally fixed manner to a hollow shaft arranged coaxially above the output shaft, which hollow shaft is connected in a rotationally fixed manner to an idler gear of the immediately axially adjacent spur gear stage of the manual transmission via a coupling switching element in order to couple the internal combustion engine and in a rotationally fixed manner to the idler gear of the immediately axially adjacent spur gear stage of the manual transmission via a coupling switching element in order to bridge the superposition gear, and in a rotationally fixed manner to the second input element or the output element of the superposition gear via a bridging switching element in order to bridge the superposition gear, that the second input element of the superposition gear is permanently in drive connection with the rotor of the electric machine, and that the output element of the superposition gear is connected in a rotationally fixed manner to the output shaft.

[0003] Furthermore, DE 10 2020 125 276 A1 discloses a hybrid drive arrangement with an internal combustion engine as the first drive machine, which has a first drive shaft, and an electromechanical energy converter as the second drive machine, which has a second drive shaft, and with a switchable traction transmission device with a first transmission input shaft, which is selectively connectable to the first drive shaft and with a second transmission input shaft, which is permanently or selectively connectable to the second drive shaft and with a transmission output shaft, which is designed to output drive power from at least one or both drive machines to a remaining motor vehicle drive train.The traction transmission device is designed as an epicyclic transmission device and has an input planetary gear set. The input planetary gear set has at least three transmission shafts, one of which is designed as an input sun gear shaft, one as an input ring gear shaft, and one as an input planetary gear carrier shaft. One of these three transmission shafts of the input planetary gear set is designed as the first transmission input shaft. A first torsional vibration reduction device is arranged between the first drive shaft and the first transmission input shaft. A second torsional vibration reduction device is arranged between the second drive shaft and the second transmission input shaft.

[0004] The publications DE 690 10 472 T2, DE 10 2013 204 172 A1, DE 10 2016 221 796 A1, DE 10 2021 211 239 A1 and DE 10 2017 221 775 A1 also disclose generic hybrid transmissions with planetary gear stages.

[0005] The object of the invention is to provide an alternative hybrid transmission for a motor vehicle. In particular, the hybrid transmission should be compact and capable of being installed in a front-transverse arrangement in the motor vehicle. This object is achieved by the subject matter of independent patent claim 1. Advantageous embodiments are the subject matter of the dependent claims, the following description, and the figures.

[0006] A hybrid transmission according to the invention for a motor vehicle comprises • a first transmission input shaft for connecting a crankshaft of an internal combustion engine, • a second transmission input shaft for connecting a rotor shaft of a first electric machine, • a first planetary gear set with a sun gear, a ring gear and a planet carrier, • a second planetary gear set with a sun gear, a ring gear and a planetary carrier, wherein the two planetary gear sets and the two transmission input shafts are arranged coaxially to each other, • a main output shaft arranged coaxially to the two planetary gear sets, • at least a first switching element, a second switching element, a third switching element, a fourth switching element and a fifth switching element, wherein all five switching elements are arranged coaxially to the two planetary gear sets.

[0007] The connection of a shaft or device to another shaft or device means that these shafts or devices are either directly connected to one another or indirectly connected to one another via at least one additional component, in particular via additional shafts and gears. For example, the crankshaft of the internal combustion engine is drive-connected to the first transmission input shaft via at least one additional shaft. For example, the rotor shaft of the electric motor is drive-connected to the second transmission input shaft via at least one additional shaft.

[0008] In particular, the two transmission input shafts are coaxial with each other and arranged axially adjacent to each other, i.e., not overlapping. A transmission input shaft is understood to be a transmission element designed for connection to a respective drive motor, in particular to a crankshaft of the internal combustion engine or a rotor shaft of the electric motor. The drive power generated by the internal combustion engine and / or the first electric motor is combined in the hybrid transmission, particularly superimposed in the planetary gear sets, and transmitted via the main output shaft, for example, to a differential.

[0009] The first planetary gear set comprises a plurality of planet gears that are rotatably mounted on the planet carrier of the first planetary gear set and mesh with, or are in tooth engagement, the sun gear and the ring gear of the first planetary gear set. The first planetary gear set is preferably designed as a negative planetary gear set. A negative planetary gear set has a sun gear, a ring gear, a planet carrier, and a plurality of planet gears, wherein each planet gear is rotatably arranged on the planet carrier and meshes with the sun gear and the ring gear. The second planetary gear set comprises a plurality of planet gears that are rotatably mounted on the planet carrier of the second planetary gear set and mesh with, or are in tooth engagement, the sun gear and the ring gear of the second planetary gear set. The second planetary gear set is preferably designed as a negative planetary gear set.

[0010] The combination of the two planetary gear sets with at least five shifting elements results in several functional options for the hybrid drive train, for example, combustion engine or hybrid driving modes, electric motor driving modes, and electrodynamic starting modes. The hybrid transmission is particularly compact due to the arrangement and connection of the two planetary gear sets and the five shifting elements. In a combustion engine driving mode, the motor vehicle is in combustion engine operation using the combustion engine alone or in hybrid operation with a combination of combustion engine and first electric motor. With a combination of combustion engine and first electric motor, each acting on the output, the combustion engine operation is hybrid operation.To select a combustion engine driving mode, three of the at least five shift elements are closed. The hybrid transmission allows at least three hybrid or combustion engine gears to be implemented. If only the fifth shift element is closed and the remaining shift elements are open, a purely electric gear is possible, with the combustion engine decoupled from the main output shaft. Furthermore, traction assistance in hybrid mode can be provided with the help of the first electric motor during gear shifts. The gear shifts can be output-assisted or electrodynamic.

[0011] The hybrid transmission preferably has exactly five shifting elements. According to the invention, the five shifting elements are designed to be positively connected, and at least three of the five shifting elements are arranged axially between the two planetary gear sets. By arranging three of the five shifting elements axially between the two planetary gear sets, the hybrid transmission is designed to be more compact and the connection of the planetary gear sets is improved. A positively connected shifting element is understood to be a shifting element which, for connecting two components, in particular two shafts, has teeth and / or claws which engage with one another in a positively connected manner to establish the rotationally fixed connection, wherein the transmission of power from one clutch part to the other clutch part of the shifting element, in a fully closed state, occurs primarily through a positive connection. For example, all five shifting elements are designed as claw clutches.Positive-locking shift elements increase the compactness and efficiency of the hybrid transmission.

[0012] According to the invention, the hybrid transmission comprises a differential that is arranged coaxially to the two planetary gear sets and has a first and second side shaft, wherein the main output shaft is at least indirectly connected to the differential, and wherein the side shafts of the differential are configured to connect a respective wheel of the motor vehicle. In particular, the main output shaft is at least indirectly connected to a differential carrier. If a component or device is configured for a function or connection, this is to be understood that this component or device is specifically designed and / or specially equipped for this purpose. The drive power is distributed in the differential between the two side shafts and transmitted to a drive wheel of the motor vehicle that is operatively connected to the respective side shaft.In particular, the first transmission input shaft, the second transmission input shaft, and the main output shaft are designed as hollow shafts, with the second side shaft of the differential extending substantially axially through the entire hybrid transmission. This allows the hybrid transmission to be more compact in both the radial and axial directions. Preferably, the side shafts of the differential are designed as central shafts of the hybrid transmission.

[0013] The differential can be designed, for example, as a bevel gear differential, a spur gear differential, or a planetary gear differential. The differential's side shafts are arranged together on an output axle of the motor vehicle, with the first transmission input shaft and the second transmission input shaft arranged coaxially to the output axle, and the combustion engine and the first electric motor arranged axially parallel to the output axle. The output axle is preferably the front-wheel drive axle of the motor vehicle. Thus, the hybrid transmission is installed in a front-transverse arrangement in the motor vehicle.

[0014] According to the invention, the differential is arranged first, adjacent to it, the second planetary gear set, adjacent to it, the connection of the first electric machine, adjacent to it, the fifth shifting element, adjacent to it, the third shifting element, adjacent to it, the fourth shifting element, adjacent to it, the first planetary gear set, adjacent to it, the connection of the internal combustion engine, adjacent to it, the second shifting element, and adjacent to it, the first shifting element. In other words, the differential is located at a first end section of the housing, and the first shifting element is arranged at a second end section of the housing, which is arranged opposite the first housing section.

[0015] The respective drive motor is preferably connected via at least one traction mechanism and / or at least one idler gear. This axial arrangement of the transmission elements makes the hybrid transmission more compact both axially and radially. Optionally, a gear ratio can be arranged axially between the differential and the superposition gear. Furthermore, a sixth shift element can optionally be arranged axially between the fifth shift element and the third shift element.

[0016] According to a preferred embodiment, the hybrid transmission has a third planetary gear set, which is arranged coaxially to the two planetary gear sets and in the power flow between the second planetary gear set and the differential. In particular, the third planetary gear set has a sun gear, a ring gear, and a planet carrier, wherein the sun gear of the third planetary gear set is rotationally fixedly connected to the planet carrier of the second planetary gear set, wherein the ring gear of the third planetary gear set is rotationally fixedly connected to a housing of the hybrid transmission, wherein the planet carrier of the third planetary gear set is rotationally fixedly connected to a differential carrier of the differential. A rotationally fixed connection is understood to be a non-switchable connection between two components which transmits speed and torque. Rotationally fixed connections increase the compactness and reduce the weight of the hybrid transmission.The third planetary gear set generates a constant gear ratio and comprises several planetary gears that are rotatably mounted on the planetary carrier and mesh with the sun gear and the ring gear. Therefore, the third planetary gear set is preferably designed as a negative planetary gear set.

[0017] According to a preferred embodiment, the sun gear of the first planetary gear set is connected in a rotationally fixed manner to a housing of the hybrid transmission, wherein the ring gear of the first planetary gear set is connected to the first transmission input shaft in the closed state of the first shifting element, wherein the planet carrier of the first planetary gear set is connected to the first transmission input shaft in the closed state of the second shifting element and is connected to the ring gear of the second planetary gear set in the closed state of the fourth shifting element.

[0018] According to a preferred embodiment, the sun gear of the second planetary gear set is connected in a rotationally fixed manner to the second transmission input shaft, wherein the ring gear of the second planetary gear set is connected to the ring gear of the first planetary gear set when the third shifting element is engaged, wherein the fifth shifting element blocks the second planetary gear set when engaged, wherein the planet carrier of the second planetary gear set is connected in a rotationally fixed manner to the main output shaft. For example, the ring gear of the second planetary gear set is connected in a rotationally fixed manner to the sun gear of the second planetary gear set when the fifth shifting element is engaged, wherein the sun gear of the second planetary gear set is connected in a rotationally fixed manner to the second transmission input shaft. Alternatively, the fifth shifting element can connect any two other elements of the second planetary gear set, for example the sun gear and the planet carrier or the ring gear and the planet carrier.Therefore, the fifth shift element is designed to lock the second planetary gear set. When the second planetary gear set is locked, the gear ratio is always 1, regardless of the number of teeth. In other words, the second planetary gear set rotates as a block.

[0019] According to an alternative embodiment, the ring gear of the second planetary gear set is connected in a rotationally fixed manner to the second transmission input shaft, wherein the sun gear of the second planetary gear set is connected to the ring gear of the first planetary gear set when the third shifting element is engaged, wherein the fifth shifting element blocks the second planetary gear set when engaged, wherein the planet carrier of the second planetary gear set is connected in a rotationally fixed manner to the main output shaft. For example, the ring gear of the second planetary gear set is connected in a rotationally fixed manner to the sun gear of the second planetary gear set when the fifth shifting element is engaged, wherein the ring gear of the second planetary gear set is connected in a rotationally fixed manner to the second transmission input shaft. Alternatively, the fifth shifting element can connect any two other elements of the second planetary gear set, for example the sun gear and the planet carrier or the ring gear and the planet carrier.

[0020] According to a preferred embodiment, the hybrid transmission has a sixth positive-locking shifting element, which is arranged coaxially with the two planetary gear sets and, in a closed state, connects the ring gear of the second planetary gear set to a housing of the hybrid transmission. Thus, the sixth positive-locking shifting element is configured, in the closed state, to fix the ring gear of the second planetary gear set stationary to the housing of the hybrid transmission. In particular, the fifth positive-locking shifting element creates an additional electromotive gear with a shorter gear ratio. The short electromotive gear is preferably used for starting in reverse.

[0021] According to a preferred embodiment, the first and second shifting elements are combined to form a first double shifting element. According to a preferred embodiment, the third and fourth shifting elements are combined to form a second double shifting element. According to a preferred embodiment, the fifth and sixth shifting elements are combined to form a third double shifting element. The respective double shifting element has, in particular, a single shift fork and a single actuator for switching the two respective shifting elements. This saves installation space, weight, and transmission components. The respective double shifting element is designed coaxially to the planetary gear sets, the transmission input shafts, and the differential, with the second side shaft extending axially through all of the double shifting elements.

[0022] According to a preferred embodiment, a second electric machine is configured to be connected to the first transmission input shaft. The second electric machine is preferably designed as a starter generator, in particular as a high-voltage starter generator. In particular, the second electric machine is arranged axially parallel to the internal combustion engine as well as to the first electric machine and the superposition gearbox. For example, the second electric machine is connected via a traction drive to a shaft arranged coaxially to the crankshaft of the internal combustion engine, wherein this shaft is connected to the first transmission input shaft via a further traction mechanism. The internal combustion engine is preferably started from a purely electric driving mode via the second electric machine. Furthermore, the second electric machine is provided for supplying power to the on-board electrical system of the motor vehicle.Serial creeping, especially forward or reverse driving of the vehicle, is also advantageous using the second electric motor. The second electric motor can also be used advantageously to support the speed control of the combustion engine during coupling and gear shifting.

[0023] According to a preferred embodiment, a damping device is arranged axially parallel to the first transmission input shaft, wherein the damping device is configured to connect the crankshaft of the internal combustion engine to the hybrid transmission. The damping device can comprise a torsional damper and / or a mass damper and / or a slip clutch. The torsional damper can be designed as a dual-mass flywheel. The mass damper can be designed as a speed-adaptive mass damper.

[0024] According to a preferred embodiment, a shifting element designed as a separating clutch is arranged axially parallel to the first transmission input shaft, wherein the separating clutch is configured to decouple the hybrid transmission from the crankshaft of the internal combustion engine. The separating clutch is thus arranged in the drive train between the internal combustion engine and the first transmission input shaft. Furthermore, the separating clutch can be arranged downstream of the damping device in the power flow from the internal combustion engine. By means of the separating clutch, the internal combustion engine can be decoupled for purely electric driving, whereby the electric driving operation of the motor vehicle becomes more energy-efficient. The separating clutch can be designed either as a positive or a non-positive shifting element. A separating clutch designed as a positive shifting element is more compact and has fewer losses than a non-positive shifting element.One advantage of a clutch designed as a frictional engagement shift element is the ability to open it even under load, for example, during emergency braking or a malfunction of the combustion engine. In particular, a frictional engagement clutch can also be closed when the speed of the two clutch components differs, allowing, for example, a so-called "inertial start" of the combustion engine using the second electric motor. The inertial mass of the second electric motor is utilized to start the combustion engine.

[0025] According to a preferred embodiment, the first transmission input shaft is designed to be connected to the internal combustion engine arranged axially parallel to the superposition gearbox at least via a traction means and / or via at least one intermediate gear, wherein the second transmission input shaft is designed to be connected to the first electric machine arranged axially parallel to the superposition gearbox at least via a traction means and / or via at least one intermediate gear. The connection by means of a traction means and / or via at least one intermediate gear, for example via a gear chain, is a non-switchable connection which is intended for the permanent transmission of a rotational speed and / or a torque. The connection can be made either directly or via a fixed transmission ratio. The connection can be made, for example, via a shaft, a gearing, in particular a spur gearing, and / or a belt means.For example, the traction means is a chain or a belt. Preferably, the traction means wraps around a first toothed section arranged coaxially to the crankshaft of the internal combustion engine and a second toothed section arranged coaxially to the first transmission input shaft. Alternatively, the internal combustion engine can be connected via a gear chain. For example, several gears form a gear chain, with at least one gear being arranged coaxially to the crankshaft of the internal combustion engine and at least one further gear being arranged coaxially to the first transmission input shaft. In particular, an intermediate gear is arranged between the two gears, with the intermediate gear meshing with both gears. Preferably, the traction means wraps around a first toothed section arranged coaxially to the rotor shaft of the first electric machine and a second toothed section arranged coaxially to the second transmission input shaft.Alternatively, the first electric motor can be connected via a gear chain. For example, several gears form a gear chain, with one of the gears arranged coaxially to the rotor shaft of the first electric motor, and another gear arranged coaxially to the second transmission input shaft. In particular, an intermediate gear is arranged between the two gears.

[0026] A motor vehicle according to the invention comprises an internal combustion engine, at least one first electric machine, and a hybrid transmission according to the invention, wherein the hybrid transmission, the internal combustion engine, and the first electric machine are arranged axially parallel to one another. Optionally, the motor vehicle comprises at least one second electric machine arranged on a rear-drive axle and thus axially parallel to the hybrid transmission, the internal combustion engine, and the first electric machine. Furthermore, the motor vehicle optionally comprises at least one further electric machine arranged axially parallel to the hybrid transmission, the internal combustion engine, and the first electric machine on the front axle of the motor vehicle.

[0027] In the following, embodiments of the invention are explained in more detail with reference to the schematic drawings, in which identical or similar elements are provided with the same reference numerals. Herein: Fig. 1a shows a section of a drive train with a hybrid transmission according to the invention according to a first embodiment, Fig. 1b a motor vehicle with the drive train according to Fig. 1a, Fig. 1c shows a shift matrix for the hybrid transmission of the drive train according to the first embodiment, Fig. 2 shows a section of a drive train with a hybrid transmission according to the invention according to a second embodiment, Fig. 3 shows a section of a drive train with a hybrid transmission according to the invention according to a third embodiment, Fig. 4 shows a drive train with a hybrid transmission according to the invention according to a fourth embodiment, and Fig. 5 shows a drive train with a hybrid transmission according to the invention according to a fifth embodiment.

[0028] Fig. 1a shows a section of a drive train with a hybrid transmission 1 according to the invention according to a first embodiment. The hybrid transmission 1 is according to Fig. 1b is shown in a highly simplified manner installed in a motor vehicle 100.

[0029] Fig. Figure 1b shows the motor vehicle 100 with two axles 101, 102 and four wheels 111, 112, 113, 114, wherein the hybrid transmission 1 is arranged on the first axle 101, in this case the front axle of the motor vehicle 100. The hybrid transmission 1 is drivingly connected to a first electric machine 5 and an internal combustion engine 3, wherein the first electric machine 5 and the internal combustion engine 3 are arranged around the first axle 101. A second electric machine 7 for the electric drive of the rear axle is arranged on the second axle 102, in this case the rear axle of the motor vehicle 100. The internal combustion engine 3, together with the two electric motors 5, 7 and the hybrid transmission 1, forms the drive train 103 of the motor vehicle 100. The hybrid transmission 1 is arranged transversely to the vehicle's longitudinal direction, with the internal combustion engine 3 and the two electric motors 5, 7 being arranged axially parallel to the hybrid transmission 1.The hybrid transmission 1 has a differential 6 with two side shafts 6.1, 6.2. The drive power of the two drive motors, namely the internal combustion engine 3 and / or the first electric motor 5, is distributed to the drive wheels 111, 112 on the first axle 101 of the motor vehicle 100 via the two side shafts 6.1, 6.2 of the differential 6. The second electric motor 7 on the second axle 102, in particular, implements an all-wheel drive system. For example, the second electric motor 7 can also be connected to the drive wheels 113, 114 of the second axle 102 via a differential (not shown in detail) on the second axle 102 via side shafts. Alternatively, the drive on the second axle 102 of the motor vehicle 100 can be omitted, thereby saving costs, weight, and installation space.

[0030] According to Fig. 1a, the hybrid transmission 1 comprises a first transmission input shaft 2 for connecting a crankshaft 3.1 of the internal combustion engine 3 and a second transmission input shaft 4 for connecting a rotor shaft 5.1 of the first electric machine 5, as well as five positive-locking shifting elements A, B, C, D, E, which are designed, for example, as claw clutches. The two transmission input shafts 2, 4 are arranged coaxially to one another and axially adjacent to one another, such that the two transmission input shafts 2, 4 do not overlap in the axial direction. The first and second positive-locking shifting elements A, B are arranged coaxially to the two transmission input shafts 2, 4 and are combined to form a first double shifting element DS1, wherein the first double shifting element DS1 can be switched by a single actuator.The third and fourth positive-locking shift elements C, D are arranged coaxially to the two transmission input shafts 2, 4 and are combined to form a second double shift element DS2, wherein the second double shift element DS2 can be switched by a single actuator.

[0031] The hybrid transmission 1 has a first planetary gear set P1 with a sun gear P11, a ring gear P12 and a planet carrier P13, wherein planet gears P14 are rotatably mounted on the planet carrier P13 and mesh with the sun gear P11 and the ring gear P12. The hybrid transmission 1 has a second planetary gear set P2 with a sun gear P21, a ring gear P22 and a planet carrier P23, wherein planet gears P24 are rotatably mounted on the planet carrier P23 and mesh with the sun gear P21 and the ring gear P22. The two planetary gear sets P1, P2 and the two transmission input shafts 2, 4 are arranged coaxially to one another. The third, fourth and fifth shifting elements C, D, E are arranged axially between the two planetary gear sets P1, P2. The sun gear P11 of the first planetary gear set P1 is connected in a rotationally fixed manner to a housing G of the hybrid transmission 1.The ring gear P12 of the first planetary gear set P1 is connected to the first transmission input shaft 2 when the first shifting element A is engaged. The planet carrier P13 of the first planetary gear set P1 is connected to the first transmission input shaft 2 when the second shifting element B is engaged, and to the ring gear P22 of the second planetary gear set P2 when the fourth shifting element D is engaged. The sun gear P21 of the second planetary gear set P2 is connected in a rotationally fixed manner to the second transmission input shaft 4. The ring gear P22 of the second planetary gear set P2 is connected in a rotationally fixed manner to the ring gear P12 of the first planetary gear set P1 when the third shifting element C is engaged, and in a rotationally fixed state of the fifth shifting element E is connected to the second transmission input shaft 4. The planet carrier P23 of the second planetary gear set P2 is connected in a rotationally fixed manner to the main output shaft 10.

[0032] The main output shaft 10 is connected to the Fig. 1b shown differential 6. For simplification, Fig. 1a neither the differential with the two side shafts nor the combustion engine and its connection are shown, but only the core section of the hybrid transmission 1. Despite this highly simplified representation, it should be noted that the first transmission input shaft 2, the second transmission input shaft 4, a first intermediate shaft 11, which is arranged coaxially to the two transmission input shafts 2, 4 and radially inside the first transmission input shaft 2, and a second intermediate shaft 12, which is arranged coaxially to the two transmission input shafts 2, 4 and radially inside the second transmission input shaft 4, are designed as hollow shafts, wherein the second side shaft of the differential extends essentially axially through the entire hybrid transmission 1, in particular through the two transmission input shafts 2, 4, through the two intermediate shafts 11, 12 and through all shift elements A, B, C, D, E.The first intermediate shaft 11 is rotationally fixedly connected to the ring gear P12 of the first planetary gear set P1. The second intermediate shaft 12 is rotationally fixedly connected to the ring gear P22 of the second planetary gear set P2.

[0033] A gear 20 is arranged on the first transmission input shaft 2, this gear 20 being part of a traction drive (not shown in detail) for connecting the crankshaft of the internal combustion engine. Furthermore, a gear 40 is arranged on the second transmission input shaft 4, this gear 40 being connected in a rotationally fixed manner to the second transmission input shaft 4 and being part of a gear chain for connecting the rotor shaft 5.1 of the first electric machine 5. The gear chain further comprises the intermediate gear 42 and a gear 41 that is connected in a rotationally fixed manner to the rotor shaft 5.1. Thus, the drive power of the first electric machine 5 is transmitted via the gear chain by means of the intermediate gear 42 from the rotor shaft 5.1 to the second transmission input shaft 4, which is arranged axially parallel thereto. When the fifth shifting element E is closed, the sun gear P21 of the second planetary gear set P2 is connected to the ring gear P22 of the second planetary gear set P2.This blocks the second planetary gear set P2.

[0034] According to an axial sequence beginning at a first end section of the hybrid transmission 1, the second planetary gear set P2 is arranged first, adjacent to it the connection of the first electric machine 5, adjacent to it the fifth shifting element E, adjacent to it the third shifting element C, adjacent to it the fourth shifting element D, adjacent to it the first planetary gear set P1, adjacent to it the connection of the combustion engine 3, adjacent to it the second shifting element B, and adjacent to it the first shifting element A. Thus, the first double shifting element DS1 is arranged in a second end section of the hybrid transmission 1, which is opposite the first end section.

[0035] The advantages of the present hybrid transmission 1 are particularly its simple and compact design, the use of only three actuators for switching the five positive-locking shifting elements A, B, C, D, and E, low component loads and low transmission losses due to the positive-locking shifting elements A, B, C, D, and E, good gearing efficiency both in terms of the combustion engine and electrically, and a good gear ratio series. Due to the axial arrangement of three of the five shifting elements A, B, C, D, and E between the two planetary gear sets P1, P2 and the connection of the two planetary gear sets P1, P2, no countershaft is required, whereby the hybrid transmission 1 exhibits maximum compactness, particularly in the radial direction.

[0036] The drive train with the hybrid transmission 1 according to Fig. 1a has several driving modes, which are shown in the switching matrix according to Fig. 1c, wherein the columns of the shift matrix list the respective shift elements A, B, C, D, E, and wherein the rows of the shift matrix list the respective driving modes H1, H2, H3, E2, EDA1, EDA2, EDA3 of the motor vehicle 100. By entering a cross in a respective box of the shift matrix, a closed state of the respective shift element A, B, C, D, E is represented, wherein no entry indicates an open state of the respective shift element A, B, C, D. By means of the four positive shift elements A, B, C, D, three combustion engine gears or hybrid driving modes H1, H2, H3, one purely electric motor gear or electric motor driving mode E2, and three electrodynamic starting modes EDA1, EDA2, EDA3 are realized.

[0037] In a first hybrid driving mode H1, the first, fourth, and fifth shift elements A, D, E are closed, while the second and third shift elements B, C are open. In a second hybrid driving mode H2, the first, third, and fifth shift elements A, C, E are closed, while the second and fourth shift elements B and D are open. In a third hybrid driving mode H3, the second, third, and fifth shift elements B, C, E are closed, while the first and fourth shift elements A, D are open. In the three hybrid driving modes H1, H2, H3, the combustion engine 3 is always involved in driving the vehicle 100, while the first electric machine 5 can assist the drive. In all three hybrid driving modes H1, H2, H3, the shift element E is closed. Thus, the first electric machine 5 is drivingly connected to the main output shaft 10.

[0038] In a purely electric driving mode E2, only the fifth switching element E is closed, while the first, second, third, and fourth switching elements A, B, C, D are open. The vehicle 100 is driven exclusively by the first electric motor 5, with the combustion engine 3 decoupled from the drive. In addition to the fifth switching element E, any two additional switching elements A, B, C, D can be closed in the purely electric driving mode E2.

[0039] The vehicle 100 is started via the superposition gear 6 using the first driving mode, electrodynamic starting EDA1. In the first electrodynamic starting mode EDA1, the first and fourth switching elements A, D are closed, while the second, third, and fifth switching elements B, C, E are open. This creates an electrodynamic state at the second planetary gear set P2. The internal combustion engine 3 is then connected via the first planetary gear set P1 to the ring gear P22 of the second planetary gear set P2, with the first electric machine 5 supporting the torque of the internal combustion engine 3 on the sun gear P21 of the second planetary gear set P2, with the planet carrier P32 of the second planetary gear set P2 being connected to the main output shaft 10. From this EDA mode, the internal combustion engine 3 can enter driving mode H1 because the first and fourth switching elements A, D are closed in this driving mode.In a second driving mode, electrodynamic start-up EDA2, the first and third switching elements A, C are closed, while the second, fourth and fifth switching elements B, D, E are open. In a third driving mode, electrodynamic start-up EDA3, the second and third switching elements B, C are closed, while the first, fourth and fifth switching elements A, D, E are open.

[0040] A powershift from the first hybrid driving mode H1 to the second hybrid driving mode H2 is possible, as is a powershift from the second hybrid driving mode H2 to the third hybrid driving mode H3. An electrodynamic state of the hybrid transmission 1 is used both for electrodynamic starting and for these powershifts. Both powershifts are performed with output support by the first electric motor 5, with the fifth shift element E always closed.

[0041] For example, the power shift from hybrid driving mode H1 to hybrid driving mode H2 occurs through the sequence of the following method steps: In the initial state, hybrid driving mode H1, the shift elements A, D, E are closed. The torques of the combustion engine 3 and the first electric machine 5 are adjusted such that, on the one hand, the desired output torque is provided and, on the other hand, the positive shift element D to be designed is load-free. In particular, a load reduction occurs on the fourth shift element D and a simultaneous load build-up on the first electric machine 5. The fourth shift element D is then opened. The speed of the combustion engine 3 is reduced so that the third shift element C becomes synchronous. For this purpose, the combustion engine 3 goes into overrun mode. The third shift element C can then be engaged. The first and fifth shift elements A, E remain closed during the shift.The powershift from the second hybrid driving mode H2 to the third hybrid driving mode H3 proceeds in the same way as the powershift from the first hybrid driving mode H1 to the second hybrid driving mode H2, but with the necessary shifting elements according to the shift matrix. A downshift occurs analogously to an upshift, only in the reverse order of the process steps. Overrun shifts are also possible, since the first electric motor 5 can support a torque on the first planetary gear set P1 by braking.

[0042] Fig. 2 shows a second embodiment of the hybrid transmission 1 in a drive train which is only partially shown, wherein this second embodiment of the hybrid transmission 1 is essentially based on the embodiment of the hybrid transmission 1 according to Fig. 1a. Therefore, reference is made to the explanations to Fig. 1a. The embodiment according to Fig. 2 differs from the embodiment according to Fig. 1a by a sixth positive-locking shifting element F, which is arranged coaxially to the two planetary gear sets P1, P2 and axially between the two planetary gear sets P1, P2. The fifth shifting element E, in a closed state, connects the ring gear P22 of the second planetary gear set P2 to a housing G of the hybrid transmission 1. The fifth shifting element E realizes a further electric driving mode, wherein for this purpose only the sixth shifting element F is closed and the first, second, third, fourth and fifth shifting elements A, B, C, D, E are open. In this further electric driving mode, a gear ratio for the first electric machine 5 is shorter than in the electric driving mode E2, wherein the drive of the vehicle 100 is effected exclusively via the first electric machine 5, and wherein the combustion engine 3 is decoupled from the drive.This additional electric driving mode is preferably used for starting off in reverse, as no EDA mode is available when reversing. In this way, a high axle torque is possible in a serial drive mode when reversing, and due to the lower requirements for the maximum driving speed when reversing, switching to a longer electric motor gear is not necessary. In particular, the additional electric driving mode can be used as a purely electric crawler gear when driving forwards and backwards, for example in a parking garage where only limited speeds occur and operation with the combustion engine is not desired. The sixth shift element F is arranged axially adjacent to the fifth shift element E and can be combined with the fifth shift element E to form a third double shift element DS3. Otherwise, the hybrid transmission 1 according to . Fig. 1a and the hybrid transmission 1 according to Fig. 2. The switching matrix according to Fig. 1c also applies to the hybrid transmission 1 according to Fig. 2.

[0043] Fig. 3 shows a third embodiment of the hybrid transmission 1 in a drive train which is only partially shown, wherein this third embodiment of the hybrid transmission 1 is essentially based on the embodiment of the hybrid transmission 1 according to Fig. 1a. Therefore, reference is made to the explanations to Fig. 1a. The embodiment according to Fig. 3 differs from the embodiment according to Fig. 1a by a different connection of the second planetary gear set P2. In this case, the connection of the sun gear P21 of the second planetary gear set P2 is swapped with the connection of the ring gear P22 of the second planetary gear set P2. In other words, the ring gear P22 of the second planetary gear set P2 is connected in a rotationally fixed manner to the second transmission input shaft 4, wherein the sun gear P21 of the second planetary gear set P2 is connected to the ring gear P12 of the first planetary gear set P1 when the third shifting element C is engaged, and is connected to the second transmission input shaft 4 when the fifth shifting element E is engaged. Independently of this, the planet carrier P23 of the second planetary gear set P2 is connected in a rotationally fixed manner to the main output shaft 10.This connection provides the particular advantage that the first electric motor 5 on the ring gear P22 of the second planetary gear set P2 operates at a lower compensating speed in EDA driving mode and during electrodynamic shifting. Otherwise, the hybrid transmission 1 according to . Fig. 1a and the hybrid transmission 1 according to Fig. 3. The switching matrix according to Fig. 1c also applies to the hybrid transmission 1 according to Fig. 3.

[0044] Fig. 4 shows a fourth embodiment of the hybrid transmission 1 in a drive train, wherein this fourth embodiment of the hybrid transmission 1 is essentially based on the embodiment of the hybrid transmission 1 according to Fig. 1a. Therefore, reference is made to the explanations to Fig. 1a. The embodiment according to Fig. 4 differs from the embodiment according to Fig. 1a by a third planetary gear set P3, which is arranged coaxially to the two planetary gear sets P1, P2 and in the power flow between the second planetary gear set P2 and the differential 6. Furthermore, the differential 6 with the two side shafts 6.1, 6.2 and the connection of the combustion engine 3 are shown. The third planetary gear set P3 has a sun gear P31, a ring gear P32 and a planet carrier P33, wherein the sun gear P31 of the third planetary gear set P3 is rotationally fixedly connected to the planet carrier P23 of the second planetary gear set P2, wherein the ring gear P32 of the third planetary gear set P3 is rotationally fixedly connected to a housing G of the hybrid transmission 1, wherein the planet carrier P33 of the third planetary gear set P3 is rotationally fixedly connected to a differential cage 6.3 of the differential 6.

[0045] The gear 20 is arranged on the first transmission input shaft 2, wherein this gear 20 is part of a traction drive for connecting the crankshaft 3.1 of the internal combustion engine 2. This traction drive further comprises the traction mechanism 22 and a further gear 21, which is formed on a third intermediate shaft 23 arranged coaxially to the crankshaft 3.1 of the internal combustion engine 3. The internal combustion engine 3 can alternatively be connected to the first transmission input shaft 2 via a gear chain. The third intermediate shaft 23 connects the crankshaft 3.1 of the internal combustion engine 3 to the hybrid transmission 1 and a further electric machine 8 via a damping device 9, which is arranged axially parallel to the third intermediate shaft 23 and is designed as a high-voltage starter generator. The further electric machine 8 is connected to the third intermediate shaft 23 via a further traction drive. The further traction drive comprises a rotor shaft 8 which is non-rotatably connected to it.1 of the further electric machine 8, a gear 31 connected to the rotor shaft 8.1, a gear 30 which is arranged in a rotationally fixed manner on the third intermediate shaft 23, and a traction means 32 which wraps around the gear 31 on the rotor shaft 8.1 and the gear 30 on the third intermediate shaft 23. The further electric machine 10 can alternatively be connected to the third intermediate shaft 23 via a gear chain. The internal combustion engine 3 is preferably started via the further electric machine 8. Furthermore, the further electric machine 8 is provided for the power supply of the on-board electrical system of the motor vehicle, wherein it can also advantageously serve to support speed control of the internal combustion engine 3 during coupling and gear shifting. Alternatively, the further electric machine 8 can be omitted, whereby the hybrid transmission 1 becomes more compact, particularly in the radial direction. Furthermore, alternatively, the further electric machine 8 can be arranged coaxially to the internal combustion engine 3.The drive power of the combustion engine 3 is transmitted via the traction drive by means of the traction mechanism 22 from the crankshaft 3.1 to the first transmission input shaft 2, which is arranged axially parallel thereto. Otherwise, the hybrid transmission 1 according to . Fig. 1a and the hybrid transmission 1 according to Fig. 4. The switching matrix according to Fig. 1c also applies to the hybrid transmission 1 according to Fig. 4.

[0046] Fig. 5 shows a fifth embodiment of the hybrid transmission 1 in a drive train, wherein this fifth embodiment of the hybrid transmission 1 is essentially based on the embodiment of the hybrid transmission 1 according to Fig. 4. Therefore, reference is made to the explanations to Fig. 4 and Fig. 1a. The embodiment according to Fig. 5 differs from the embodiment according to Fig. 4 by a switching element designed as a separating clutch K0, which is arranged axially parallel to the first transmission input shaft 2 and is designed to decouple the hybrid transmission 1 from the crankshaft 3.1 of the internal combustion engine 3. The separating clutch K0 is arranged coaxially to the crankshaft 3.1 of the internal combustion engine 3. In an open state of the separating clutch K0, the third intermediate shaft 23 is decoupled from the damping device 9 and thus from the crankshaft 3.1 of the internal combustion engine 3. In the present case, the separating clutch K0 is designed as a positive-locking switching element. Alternatively, the separating clutch K0 can be designed as a non-positive switching element, for example as a multi-plate clutch. Otherwise, the hybrid transmission 1 according to Fig. 4 and the hybrid transmission 1 to Fig. 5. The switching matrix according to Fig. 1c also applies to the hybrid transmission 1 according to Fig. 5. LIST OF REFERENCE SYMBOLS: 1 hybrid transmission 2 first transmission input shaft 3 combustion engine 3.1 Crankshaft 4 second transmission input shaft 5 first electric machine 5.1 Rotor shaft 6 Differential 6.1 first side wave 6.2 second side shaft 6.3 Differential cage 7 second electric machine 8 additional electric machines 8.1 Rotor shaft 9 Damping device 10 Main output shaft 11 first intermediate shaft 12 second intermediate shaft 20 gear 21 gear 22 traction devices 23 third intermediate shaft 30 gear 31 gear 32 traction devices 40 gear 41 gear 42 intermediate gear G Housing DS1 first double switching element DS2 second double switching element DS3 third double switching element A first switching element B second switching element C third switching element D fourth switching element E fifth switching element F sixth switching element K0 separating clutch H1 first combustion engine gear H2 second combustion engine gear H3 third combustion engine gear E2 electromotive gear EDA1 first electrodynamic starting mode EDA2 second electrodynamic starting mode EDA3 third electrodynamic starting mode P1 first planetary gear set P11 Sun gear of the first planetary gear set P12 Ring gear of the first planetary gear set P13 Planet carrier of the first planetary gear set P14 Planet gear of the first planetary gear set P2 second planetary gear set P21 Sun gear of the second planetary gear set P22 Ring gear of the second planetary gear set P23 Planet carrier of the second planetary gear set P24 Planetary gear of the second planetary gear set P3 third planetary gear set of the third planetary gear set P31 Sun gear of the third planetary gear set P32 Ring gear of the third planetary gear set P33 Planet carrier of the third planetary gear set P34 Planet gear of the third planetary gear set 100 motor vehicles 101 first axle of the motor vehicle 102 second axle of the motor vehicle 103 Powertrain 111 Wheel 112 wheels 113 wheels 114 wheels

Claims

[1] Hybrid transmission (1) for a motor vehicle (100), comprising • a first transmission input shaft (2) for connecting a crankshaft (3.1) of an internal combustion engine (3), • a second transmission input shaft (4) for connecting a rotor shaft (5.1) of a first electric machine (5), • a first planetary gear set (P1) with a sun gear (P11), a ring gear (P12) and a planet carrier (P13), • a second planetary gear set (P2) with a sun gear (P21), a ring gear (P22) and a planetary carrier (P23), wherein the two planetary gear sets (P1, P2) and the two transmission input shafts (2, 4) are arranged coaxially to one another, • a main output shaft (10) arranged coaxially to the two planetary gear sets (P1, P2), • at least one first shifting element (A), one second shifting element (B), one third shifting element (C), one fourth shifting element (D) and one fifth shifting element (E), wherein all five shifting elements (A, B, C, D, E) are arranged coaxially to the two planetary gear sets (P1, P2), and wherein all five shifting elements (A, B, C, D, E) are designed as positive-locking shifting elements and at least three of the five shifting elements (A, B, C, D, E) are arranged axially between the two planetary gear sets (P1, P2), characterized bythat there is also a differential (6) which is arranged coaxially to the two planetary gear sets (P1, P2) and has a first and second side shaft (6.1, 6.2), wherein the main output shaft (10) is at least indirectly connected to the differential (6), and wherein the side shafts (6.1, 6.2) of the differential (6) are designed to connect a respective wheel of the motor vehicle (100), and wherein, according to an axial sequence, first the differential (6), adjacent thereto the second planetary gear set (P2), adjacent thereto the connection of the first electric machine (5), adjacent thereto the fifth shifting element (E), adjacent thereto the third shifting element (C), adjacent thereto the fourth shifting element (D), adjacent thereto the first planetary gear set (P1), adjacent thereto the connection of the internal combustion engine (3), adjacent thereto the second shifting element (B), and adjacent thereto the first shifting element (A) are arranged. [2] Hybrid transmission (1) according to claim 1, wherein the first transmission input shaft (2), the second transmission input shaft (4) and the main output shaft (10) are designed as hollow shafts and the second side shaft (6.2) of the differential (6) extends substantially axially through the entire hybrid transmission (1). [3] Hybrid transmission (1) according to claim 2, further comprising a third planetary gear set (P3) which is arranged coaxially to the two planetary gear sets (P1, P2) and is arranged in the power flow between the second planetary gear set (P2) and the differential (6), wherein the third planetary gear set (P3) has a sun gear (P31), a ring gear (P32) and a planet carrier (P33), wherein the sun gear (P31) of the third planetary gear set (P3) is connected in a rotationally fixed manner to the planet carrier (P23) of the second planetary gear set (P2), wherein the ring gear (P32) of the third planetary gear set (P3) is connected in a rotationally fixed manner to a housing (G) of the hybrid transmission (1), wherein the planet carrier (P33) of the third planetary gear set (P3) is connected in a rotationally fixed manner to a differential cage (6.3) of the differential (6). [4] Hybrid transmission (1) according to one of the preceding claims, wherein the sun gear (P11) of the first planetary gear set (P1) is connected in a rotationally fixed manner to a housing (G) of the hybrid transmission (1), wherein the ring gear (P12) of the first planetary gear set (P1) is connected to the first transmission input shaft (2) in the closed state of the first shifting element (A), wherein the planet carrier (P13) of the first planetary gear set (P1) is connected to the first transmission input shaft (2) in the closed state of the second shifting element (B) and is connected to the ring gear (P22) of the second planetary gear set (P2) in the closed state of the fourth shifting element (D). [5] Hybrid transmission (1) according to one of the preceding claims, wherein the sun gear (P21) of the second planetary gear set (P2) is connected in a rotationally fixed manner to the second transmission input shaft (4), wherein the ring gear (P22) of the second planetary gear set (P2) is connected in the closed state of the third shifting element (C) to the ring gear (P12) of the first planetary gear set (P1), wherein the fifth shifting element (E) blocks the second planetary gear set (P2) in the closed state, wherein the planet carrier (P23) of the second planetary gear set (P2) is connected in a rotationally fixed manner to the main output shaft (10). [6] Hybrid transmission (1) according to one of claims 1 to 4, wherein the ring gear (P22) of the second planetary gear set (P2) is connected in a rotationally fixed manner to the second transmission input shaft (4), wherein the sun gear (P21) of the second planetary gear set (P2) is connected in the closed state of the third shifting element (C) to the ring gear (P12) of the first planetary gear set (P1), wherein the fifth shifting element (E) blocks the second planetary gear set (P2) in the closed state, wherein the planet carrier (P23) of the second planetary gear set (P2) is connected in a rotationally fixed manner to the main output shaft (10). [7] Hybrid transmission (1) according to one of the preceding claims, further comprising a sixth positive-locking shift element (F) which is arranged coaxially to the two planetary gear sets (P1, P2) and, in a closed state, connects the ring gear (P22) of the second planetary gear set (P2) to a housing (G) of the hybrid transmission (1). [8] Hybrid transmission (1) according to one of the preceding claims, wherein the first and second switching elements (A, B) are combined to form a first double switching element (DS1), wherein the third and fourth switching elements (C, D) are combined to form a second double switching element (DS2). [9] Hybrid transmission (1) according to one of the preceding claims, wherein a second electric machine (8) is adapted to be connected to the first transmission input shaft (2). [10] Hybrid transmission (1) according to one of the preceding claims, wherein a switching element designed as a separating clutch (K0) is arranged axially parallel to the first transmission input shaft (2), wherein the separating clutch (K0) is designed to decouple the hybrid transmission (1) from the crankshaft (3.1) of the internal combustion engine (3). [11] Hybrid transmission (1) according to one of the preceding claims, wherein the first transmission input shaft (2) is designed to be connected at least via a traction means and / or via at least one intermediate gear to the internal combustion engine (3) arranged axially parallel to the two planetary gear sets (P1, P2), wherein the second transmission input shaft (4) is designed to be connected at least via a traction means and / or via at least one intermediate gear to the first electric machine (5) arranged axially parallel to the two planetary gear sets (P1, P2). [12] Motor vehicle (100) with an internal combustion engine (3), at least one first electric machine (5) and a hybrid transmission (1) according to one of claims 1 to 11, wherein the hybrid transmission (1), the internal combustion engine (3) and the first electric machine (5) are arranged axially parallel to one another.

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