DE102021208194A1 - Transmission for a motor vehicle - Google Patents

Abstract

The invention relates to a transmission (4) for a motor vehicle, comprising an electric machine (10), a first input shaft (19), a second input shaft (20), an output shaft (21), two planetary gear sets (11, 12) and five shifting elements ( A, B, C, D, E), whereby by selectively operating the five shifting elements (A, B, C, D, E), different gears can be shifted and, in addition, different operating modes can be represented in interaction with the electric machine (10), as well as a motor vehicle drive train with such a transmission (4) and method for operating a transmission (4).

Description

The invention relates to a transmission for a motor vehicle, comprising an electric machine, a first drive shaft, a second drive shaft, an output shaft, and a first planetary gear set and a second planetary gear set, the first drive shaft being set up to connect the transmission to a drive engine of the motor vehicle , wherein the planetary gear sets each comprise a first element, a second element and a third element each, with a first, a second, a third, a fourth and a fifth switching element being provided, and with a rotor of the electric machine having the second drive shaft connected. Furthermore, the invention relates to a motor vehicle drive train, in which an aforementioned transmission is used, and a method for operating a transmission.

In hybrid vehicles, transmissions are known which, in addition to a wheel set, also have one or more electric machines. The transmission is usually designed with multiple gears, d. H. several different transmission ratios can be switched as gears between an input shaft and an output shaft by actuating corresponding switching elements, this preferably being carried out automatically. Depending on the arrangement of the shifting elements, these are either clutches or brakes. In this case, the transmission is used to suitably implement a tractive force available from a drive machine of the motor vehicle with regard to various criteria. The gears of the transmission are usually also used in conjunction with the at least one electric machine to represent purely electric driving. The at least one electric machine can often also be integrated in different ways in the transmission to represent different operating modes.

From the DE 10 2013 013 947 A1 discloses a transmission for a motor vehicle which, in addition to a first drive shaft and an output shaft, comprises two planetary gear sets and an electric machine connected to a second drive shaft. Furthermore, a total of five shifting elements are provided, via which different power flows from the first drive shaft to the output shaft can be implemented, showing different gears, and different integrations of the electric machine can also be designed. In this case, purely electric driving can also be represented by the sole drive via the electric machine.

It is the object of the present invention to provide an alternative embodiment to the transmission for a motor vehicle known from the prior art, with which different operating modes can be represented in a suitable manner with a compact structure.

This object is achieved based on the preamble of claim 1 in conjunction with its characterizing features. The dependent claims that follow each specify advantageous developments of the invention. A motor vehicle drive train is also the subject of claim 16. Furthermore, claim 17 relates to a method for operating a transmission.

According to the invention, a transmission includes an electric machine, a first input shaft, a second input shaft, an output shaft and a first planetary gear set and a second planetary gear set. The first drive shaft is designed to connect the transmission to a drive engine of the motor vehicle. The planetary gear sets each comprise a first element, a second element and a third element, one of which is preferably designed as a sun gear, one in each case as a planet carrier and one in each case as a ring gear. In addition, a first, a second, a third, a fourth and a fifth shifting element are provided, through the selective actuation of which, in particular, different power flow guides can be displayed with the shifting of different gears. Particularly preferably, exactly four different gears can be formed between the first drive shaft and the output shaft from the transmission ratio. Furthermore, a rotor of the electric machine is connected to the second drive shaft.

In the context of the invention, a “shaft” is to be understood as meaning a rotatable component of the transmission, via which a power flow can be guided between components, if necessary with simultaneous actuation of a corresponding shifting element. The respective shaft can connect components to one another axially or radially or both axially and radially. The respective shaft can also be present as an intermediate piece, via which a respective component is connected radially, for example. In addition, the respective shaft can be designed as a one-piece component or can be in multiple parts, in that the respective shaft is composed of several shaft parts connected to one another in a torque-proof manner.

In the context of the invention, “axial” means an orientation in the direction of a longitudinal central axis of the transmission, parallel to which the axes of rotation of the planetary gear sets are arranged. Under "radial" is then an orientation in diameter direction of a respective rotatable component, in particular to understand a respective shaft.

Within the scope of the invention, the first input shaft, the second input shaft and the output shaft are placed in particular lying coaxially with one another, with the two planetary gear sets also preferably being arranged coaxially with the input shafts and the output shaft.

The output shaft of the transmission preferably has a connection point, via which the output shaft is then in operative connection in the motor vehicle drive train with a differential gear arranged axially parallel to the output shaft. This connection point is preferably present as teeth on the output shaft, the connection point of the output shaft being located in particular axially in the region of one end of the transmission, at which there is also a connection point of the first drive shaft that establishes the connection to the upstream drive machine. This type of arrangement is particularly suitable for use in a motor vehicle with a drive train oriented transversely to the direction of travel of the motor vehicle. In this variant of the invention, the connection point of the first drive shaft is preferably followed axially first by the connection point of the output shaft and then by the second planetary gear set and finally the first planetary gear set. In addition, the first drive shaft is preferably present essentially as a solid shaft, to which the second drive shaft and the output shaft are placed radially surrounding as hollow shafts. The second input shaft and the output shaft each overlap axially with a part of the radially inner, first input shaft. Other shafts that connect the individual components of the transmission and in particular the elements of the planetary gear sets to one another or establish a connection when the corresponding shifting element is actuated are preferably each designed as hollow shafts that are arranged radially surrounding the first drive shaft.

As an alternative to this, in the case of the transmission according to the invention, an output can also be provided at an axial end of the transmission which is opposite to a connection point of the first drive shaft. A connection point of the output shaft is then configured at an axial end of the output shaft coaxially with a connection point of the first drive shaft, so that the input and output of the transmission are placed at opposite axial ends of the transmission. A transmission designed in this way is suitable for use in a motor vehicle with a drive train aligned in the direction of travel of the motor vehicle. The first drive shaft and also the output shaft are in particular essentially solid shafts that are placed on the face side and coaxially with one another, with the second drive shaft and any other shafts that may be present being arranged as hollow shafts, each radially surrounding the first drive shaft and the output shaft and axially overlap with a portion of the first input shaft or the output shaft. In particular, in this variant of the invention, the connection point of the first drive shaft is followed by the first planetary gear set, then the second planetary gear set and finally the connection point of the output shaft at the opposite, axial end of the transmission.

The invention now includes the technical teaching that the second drive shaft is non-rotatably connected to the first element of the second planetary gear set, while the third element of the second planetary gear set is fixed. Furthermore, the output shaft can be connected in a rotationally fixed manner to the second element of the second planetary gear set via the first shifting element and can be connected in a rotationally fixed manner to the first drive shaft by means of the second shifting element. The first drive shaft can be connected in a rotationally fixed manner to the second drive shaft via the third shifting element, while the second drive shaft can be connected in a rotationally fixed manner to the output shaft by means of the fourth shifting element. Furthermore, in the first planetary gear set there is a first coupling of the first element of the first planetary gear set with a non-rotatable component, a second coupling of the second element of the first planetary gear set with the first drive shaft and a third coupling of the third element of the first planetary gear set with the second drive shaft, wherein of these three couplings, two are present as a permanent, non-rotatable connection, while a non-rotatable connection can be established in the remaining coupling by means of the fifth switching element.

In other words, in the transmission according to the invention the second drive shaft is permanently non-rotatably connected to the first element of the second planetary gear set, while the third element of the second planetary gear set is constantly fixed and thus permanently prevented from rotating.

Closing the first switching element causes the output shaft to be connected in a rotationally fixed manner to the second element of the second planetary gear set, while actuation of the second switching element results in a rotationally fixed connection between the output shaft and the first input shaft. In the actuated state, the third switching element connects the first drive shaft and the second drive shaft to one another in a rotationally fixed manner. However In the closed state, the fourth switching element ensures that the second input shaft is connected to the output shaft in a torque-proof manner.

With regard to the first planetary gear set, there are also a total of three couplings of the elements of the first planetary gear set in the transmission according to the invention. There is a first coupling in the form of the first element of the first planetary gear set with a non-rotatable component, while in the case of the second element of the first planetary gear set there is a second coupling with the first drive shaft and in the case of the third element of the first planetary gear set there is a third coupling with the second drive shaft consists. Two of the three aforementioned couplings are implemented as permanent non-rotatable connections, while the remaining coupling is present as a connection that is only established in a non-rotatable manner by closing the fifth switching element.

A “coupling” in the case of the first planetary gear set is therefore to be understood within the meaning of the invention as a connection that either exists as a permanent connection or is established in a rotationally fixed manner only by actuating the fifth shifting element.

In the transmission according to the invention, the first shifting element, the second shifting element, the third shifting element and the fourth shifting element are present as clutches which, when actuated, connect the components of the transmission directly connected thereto in a torque-proof manner. Depending on the coupling to be produced in the first planetary gearset, the fifth shifting element is designed either as a clutch or as a brake.

A respective, permanently non-rotatable connection between components of the transmission has the consequence that rotary movements of these components take place with a fixed speed ratio or a standstill of one component inevitably also causes a standstill of the other component. A permanent non-rotatable connection is preferably realized according to the invention via one or more intermediate shafts, which can also be present as short intermediate pieces if the components are spatially close together. In concrete terms, the components that are permanently connected to one another in a rotationally fixed manner can each be present either as individual components that are rotationally fixedly connected to one another or in one piece. In the second-mentioned case, the respective components and the shaft that may be present are then formed by a common component, this being realized in particular when the respective components in the transmission are spatially close to one another.

In the case of components of the transmission which are connected to one another in a rotationally fixed manner only by actuation of a respective shifting element, a connection is also preferably implemented via one or more intermediate shafts.

The permanent fixing of a component of the transmission is realized in the sense of the invention in particular by the fact that the respective component is permanently connected in a rotationally fixed manner to a rotationally fixed component of the transmission or is rotationally fixedly connected to this rotationally fixed component by actuating the corresponding switching element. The non-rotatable component is preferably a permanently stationary component, preferably a gear housing, a part of such a gear housing or a component connected thereto in a non-rotatable manner.

The "connection" of the rotor of the electric machine to the second input shaft of the transmission is to be understood within the meaning of the invention as a connection such that there is a constant speed dependency between the rotor of the electric machine and the second input shaft. According to the invention, the electric machine can preferably be operated on the one hand in an electric motor mode and on the other hand in a generator mode, so that a drive movement can be initiated via the electric machine in the first-mentioned operating mode, while the electric machine can be used to generate electricity in the second-mentioned operating mode.

Overall, a transmission according to the invention is characterized by a compact design, low component loads, good gearing efficiency and low losses. In addition, with this structure of the transmission, there is the possibility of realizing a purely electric drive via the electric machine without having to provide a separating clutch or the like for decoupling the upstream drive machine.

With regard to the couplings of the first planetary gear set, one conceivable variant of the transmission according to the invention is that the second element of the first planetary gear set is non-rotatably connected to the first drive shaft, while the third element of the first planetary gear set is non-rotatably connected to the second drive shaft. In addition, the first element of the first planetary gear set can be fixed to the non-rotatable component via the fifth shifting element. In this case, therefore, the first coupling in the first planetary gear set becomes a non-rotatable connection only by actuating the fifth shifting element made, while the second coupling and the third coupling are present as permanent non-rotatable connections.

In a further development of the aforementioned variant, the third shifting element connects the second element and the third element of the first planetary gearset to one another in a torque-proof manner when actuated. Alternatively, a non-rotatable connection between the first element and the second element of the first planetary gear set is established via the third shifting element in its closed state, whereby it is alternatively also conceivable that the third shifting element, when actuated, shifts the first element and the third element of the first Planetary gear rotatably connected to each other. In each of the three variants mentioned above, the first planetary gearset is blocked by two of the three elements of the first planetary gearset being non-rotatably connected to one another via the third shifting element. This always results in a non-rotatable connection between the first drive shaft and the second drive shaft.

Alternatively, it is a second variant of the invention with regard to the couplings of the first planetary gear set that the first element of the first planetary gear set is fixed and the second element of the first planetary gear set is non-rotatably connected to the first drive shaft, whereas the third element of the first planetary gear set is connected by closing of the fifth switching element is connected in a rotationally fixed manner to the second drive shaft. In this variant, therefore, the first coupling and the second coupling are in the form of permanently non-rotatable connections, while the third coupling is configured as a non-rotatable connection only when the fifth switching element is actuated.

As a further alternative to the two aforementioned variants, the first element of the first planetary gear set is fixed and the third element of the first planetary gear set is non-rotatably connected to the second drive shaft, whereas the second element of the first planetary gear set is non-rotatably connected to the first drive shaft via the fifth switching element. In this respect, in this case the first coupling and the third coupling are each implemented as permanent non-rotatable connections, whereas in the case of the second coupling a non-rotatable connection is formed only by actuating the fifth switching element.

According to a further possible embodiment of the invention, four gears result between the first drive shaft and the output shaft by selectively closing the five shifting elements. Thus, a first gear between the first input shaft and the output shaft can be achieved by actuating the first and third shifting element, while a second gear between the first input shaft and the output shaft results by closing the first and fifth shifting element. A third gear between the first drive shaft and the output shaft is shifted in a first variant by actuating the first and the second shifting element, with the third gear also shifting in a second variant by actuating the second and the fourth shifting element, in a third variant by Closing the second and the fifth switching element results in a fourth variant by actuating the third and the fourth switching element and in a fifth variant by closing the second and the third switching element. In addition, a fourth gear between the first input shaft and the output shaft can also be achieved by closing the fourth and fifth shifting elements.

With a suitable selection of stationary gear ratios of the planetary gear sets, a gear ratio series suitable for use in a motor vehicle is realized. Shifting between the gears can be realized in which only the state of two shifting elements is to be varied by opening one of the shifting elements involved in the previous gear and closing another shifting element to represent the following gear. This then also means that switching between gears can take place very quickly.

• So kann ein erster Gang zwischen der zweiten Antriebswelle und der Abtriebswelle für ein rein elektrisches Fahren über die Elektromaschine in deren elektromotorischen Betrieb genutzt werden, wobei sich dieser erste Gang durch Schließen des ersten Schaltelements ergibt. Dadurch ist die zweite Antriebswelle und damit der Rotor der Elektromaschine über den zweiten Planetenradsatz mit der Abtriebswelle verbunden, indem die zweite Antriebswelle über das erste Element des zweiten Planetenradsatzes antreiben kann, während ein Abtrieb über das zweite Element des zweiten Planetenradsatzes auf die Abtriebswelle aufgrund des permanent festgesetzten, dritten Elements des zweiten Planetenradsatzes stattfindet. Eine Übersetzung dieses ersten Ganges entspricht einer Übersetzung des ersten, zwischen der ersten Antriebswelle und der Abtriebswelle wirksamen Ganges. Ist lediglich das erste Schaltelement geschlossen, so ist die dem Getriebe vorgeschaltete Antriebsmaschine abgekoppelt, da auch die erste Antriebswelle von der Abtriebswelle entkoppelt ist.

By coupling the rotor of the electric machine to the second drive shaft, different operating modes can be easily implemented:

• Thus, a first gear between the second drive shaft and the output shaft can be used for purely electric driving via the electric machine in its electromotive operation, with this first gear resulting from the closing of the first switching element. As a result, the second drive shaft and thus the rotor of the electric machine is connected to the output shaft via the second planetary gear set, in that the second drive shaft can drive via the first element of the second planetary gear set, while an output is transmitted via the second element of the second planetary gear set to the output shaft due to the permanent fixed, third element of the second planetary gear set takes place. A translation of this first gear corresponds to a translation of the first gear effective between the first input shaft and the output shaft. If only the first switching element is closed, then the drive is connected upstream of the transmission decoupled from the machine, since the first input shaft is also decoupled from the output shaft.

Starting from purely electric driving in the first gear, which is effective between the second input shaft and the output shaft, the drive machine upstream of the transmission can then be shifted to the first gear, which is effective between the first input shaft and the output shaft, or to the second gear, which is effective between the first input shaft and the output shaft effective gear or in the first variant of the third gear effective between the first drive shaft and the output shaft, since the first switching element is involved in the representation of these gears. This also has the consequence that the electric machine is always involved when one of these gears is shifted between the first drive shaft and the output shaft, so that an additional drive torque can be fed specifically via the electric machine into its electric motor operation. In addition, the motor vehicle can also be braked in each of these gears via the electric machine in its generator mode with power generation (recuperation).

In addition, a second gear can be shifted between the second input shaft and the output shaft and accordingly used for the integration of the electric machine. In this case, this second gear is achieved by actuating the fourth shifting element, so that the second input shaft is connected directly to the output shaft, as a result of which the electric machine is coupled to the output shaft. A translation of this second gear corresponds to the third gear effective between the first input shaft and the output shaft. If only the fourth shifting element is closed, then the drive machine connected upstream of the transmission is decoupled, since the first input shaft is also decoupled from the output shaft.

The engine upstream of the transmission can also be started from purely electric driving in the second gear, which is effective between the second drive shaft and the output shaft, whereby this occurs in the second variant and the fourth variant of the third gear, which is effective between the first drive shaft and the output shaft and also in the fourth gear effective between the first input shaft and the output shaft. The reason for this is that the fourth switching element is also involved in the representation of these gears. As a result, when the second or fourth variant of the third gear, effective between the first input shaft and the output shaft, or the fourth gear, effective between the first input shaft and the output shaft, is engaged, the electric machine is also always involved, whereby it is either in its electric motor operation can feed in an additional drive torque or ensure braking in their generator operation.

As a further operating mode, a charging operation of an electrical energy store can also be implemented by only the third switching element being closed in a first variant of the invention. As a result, the first drive shaft and the second drive shaft are directly connected to one another in a rotationally fixed manner, so that there is also a coupling between the electric machine and the drive machine connected upstream of the transmission. The first drive shaft and the second drive shaft run at the same speed. At the same time, there is no positive connection to the output shaft, so that the transmission is in a neutral position. Apart from a charging operation, this also allows the upstream drive machine to be started via the electric machine if the upstream drive machine is designed as an internal combustion engine.

Alternatively, a charging operation within the scope of the invention can also be presented by simply actuating the fifth switching element, whereby the second drive shaft is coupled via the first planetary gear set to the first drive shaft with translation via the first planetary gear set. In this case, the second drive shaft rotates faster than the first drive shaft with a suitable selection of a stationary transmission ratio of the first planetary gear set, with no frictional connection to the output shaft being produced at the same time. In addition to a charging operation, the upstream drive machine can also be started again, in particular if this is designed as an internal combustion engine.

Furthermore, shifts between the gears that can be represented between the first input shaft and the output shaft can be represented under load by supporting the tractive force via the electric machine: when changing gears between the first gear, which is effective between the first input shaft and the output shaft, and the second, effective gear between the input shaft and the output shaft, the traction can be supported by the electric machine when the first switching element is closed, with the synchronization of the fifth switching element to be closed taking place via a speed control of the upstream drive motor. Alternatively, this can also be done by synchronized switching elements or by another, separate synchronization device, such as a Transmission brake or another electric machine, which can be operatively connected directly or indirectly to the first drive shaft. If a further shifting element is also provided on the drive side of the first drive shaft as a separating clutch, the inertial mass of the upstream drive machine can be decoupled during synchronization.

Likewise, in the course of a gear change between the second gear effective between the first input shaft and the output shaft and the first variant of the third gear effective between the input shaft and the output shaft, the tractive force is supported via the electric machine when the first shifting element is closed, while a synchronization of the closing, second switching element takes place by speed control of the upstream drive machine. In third gear, there is then a switchover between the first variant and the second variant of the third gear, with the load-free, first shifting element being disengaged and then the likewise load-free, fourth shifting element being engaged. During this switching, only the second switching element is under load.

After this shift, it is then possible to change from the second variant of the third gear, effective between the first input shaft and the output shaft, to the fourth gear, effective between the first input shaft and the output shaft, with support for the tractive force via the electric machine when the fourth gear is closed Switching element is completed. A synchronization of the fifth switching element to be closed can be carried out again by controlling the speed of the upstream drive machine.

The transmission according to the invention can also be operated in such a way that the speed of the electric machine is reduced when driving. Hybrid driving is possible in the first variant of third gear, in that the first shifting element initially remains closed either after a shift from second to third gear supported by the electric machine or after the drive motor has been started in third gear. However, in order to reduce the speed of the electric machine in third gear at higher driving speeds, it is possible to switch from the first variant of the third gear to the second variant of the third gear, since the rotor of the electric machine has a lower speed here than in the first variant of the third Ganges. This switchover takes place while maintaining the traction via the upstream drive machine when the second switching element is closed. First of all, the load-free, first shifting element is disengaged and then the load-free, fourth shifting element is engaged, with the speed being adjusted by speed control of the electric machine.

In addition, a separating clutch can be provided between the upstream drive machine and the first input shaft of the transmission in order to decouple the drive machine in the second variant of the third gear effective between the first drive shaft and the output shaft. This makes sense if regenerative braking is also to take place via the electric machine from higher driving speeds and the drive machine is to be decoupled or switched off during this time.

In a further development of the invention, one switching element or several switching elements are each implemented as a positive-locking switching element. In this case, the respective shifting element is preferably designed either as a claw shifting element or as a blocking synchronization. Positive shifting elements have the advantage over non-positive shifting elements that lower drag losses occur in the open state, so that better efficiency of the transmission can be achieved. In particular, in the transmission according to the invention, the first shifting element, the second shifting element, the third shifting element, the fourth shifting element and the fifth shifting element are realized as positive shifting elements, so that the lowest possible drag losses can be achieved. In principle, however, one of these shifting elements or several of these shifting elements could also be designed as non-positive shifting elements, for example as lamellar shifting elements.

Provided that the elements can be connected, the planetary gear sets can each be present as a minus planetary gear set within the scope of the invention, in which case the first element of the respective planetary gear set is a sun gear, the second element of the respective planetary gear set is a planet carrier and the third element of the respective planetary gear set is a ring gear. At least one planet gear is rotatably mounted in the planet carrier and meshes with both the sun gear and the surrounding ring gear. More preferably, however, several planet gears are rotatably guided in the planet carrier.

Alternatively, one or both planetary gearsets could be present as a positive planetary gearset, provided the connection of the respective elements allows it, with the first element of the respective planetary gearset being a sun gear and the second element of the respective planetary gearset being a ring gear and in the third element of each planetary gear set by one planet web acts. In a plus planetary gear set, the elements sun gear, ring gear and planetary carrier are also present, with the latter guiding at least one pair of planetary gears in a rotatable manner, in which one planetary gear meshes with the internal sun gear and the other planetary gear meshes with the surrounding ring gear, as well as the planetary gears comb with each other.

Where it is possible to connect the individual elements, a minus planetary gearset can be converted into a plus planetary gearset, in which case the ring gear and planetary carrier connection must be swapped over compared to the negative planetary gearset design, and a gear ratio increased by one. Conversely, a plus planetary gear set could also be replaced by a minus planetary gear set, provided that the connection of the transmission elements allows this. In this case, in comparison to the plus planetary gear set, the ring gear and planet carrier connection would also have to be swapped with one another, and a gear ratio would have to be reduced by one. In the context of the invention, however, the two planetary gear sets are preferably each designed as a minus planetary gear set.

According to an embodiment of the invention, the rotor of the electric machine is rigidly connected to the second drive shaft. As an alternative to this, one possible embodiment of the invention is for the rotor to be connected to the second drive shaft via at least one transmission step. In both of the aforementioned variants, the electric machine can be arranged coaxially with the second drive shaft and the planetary gear sets, with the second variant also conceivable being an off-axis arrangement of the electric machine with respect to the second drive shaft and the planetary gear sets.

In the coaxial arrangement, the rotor of the electric machine can either be rigid, i.e. directly non-rotatable, connected to the second drive shaft or coupled to it via one or more intermediate transmission stages, with the latter enabling a more favorable design of the electric machine with higher speeds and lower torque . The at least one transmission stage can be designed as a spur gear stage and/or as a planetary stage. In the case of a coaxial arrangement of the electric machine, the first planetary gear set is also preferably arranged axially at the level of the electric machine and radially on the inside of it, so that the overall axial length of the transmission can be shortened.

If, on the other hand, the electric machine is provided with an offset axis in relation to the second drive shaft and the planetary gear sets, then a coupling takes place via one or more intermediate transmission stages and/or a traction drive. The one or more transmission stages can also be implemented individually either as a spur gear stage or as a planetary stage. A traction drive can be either a belt drive or a chain drive.

According to a further embodiment of the invention, a further electric machine is also provided, the rotor of which is rigidly connected to the first drive shaft or is coupled to the first drive shaft via at least one transmission stage. In this case, two electric machines are provided in the transmission according to the invention, one of which is connected to the second drive shaft, while the other is connected to the first drive shaft. The latter can be implemented by a direct non-rotatable connection of a rotor of the additional electric machine to the first drive shaft or as a coupling of the rotor of the additional electric machine to the first drive shaft via at least one gear ratio. The additional electric machine includes in particular a stator and a rotor and can preferably be operated on the one hand as a generator and on the other hand as an electric motor.

Advantageously, the additional electric machine can be used to implement serial operation, in which current is generated by the additional electric machine in its generator mode and when driven by the upstream drive machine, while the electric machine connected to the second drive shaft in its electric motor mode supplies this uses generated electricity to drive the motor vehicle. One of the two gears that can be displayed between the second input shaft and the output shaft is to be shifted. Furthermore, due to the permanent coupling to the first drive shaft, the additional electric machine can also be used to start the upstream drive machine.

The additional electric machine can be arranged coaxially to the first drive shaft, with alternatively an axially offset arrangement of the additional electric machine to the first drive shaft being conceivable. In the case of the coaxial arrangement, the rotor of the further electric machine can either be rigidly connected, ie directly non-rotatably, to the first drive shaft or be coupled to it via one or more intermediate transmission stages. The latter enables a more favorable interpretation of the white lower electric machine with higher speeds and lower torque. The at least one intermediate gear stage can be designed as a spur gear stage and/or as a planetary stage.

If the further electric machine is arranged off-axis relative to the first drive shaft, it is coupled to the first drive shaft, in particular via one or more intermediate transmission stages and/or a traction drive. The one or more transmission stages can also be implemented individually either as a spur gear stage or as a planetary stage. A traction drive can be either a belt drive or a chain drive.

In the variant of the transmission according to the invention, in which the fifth switching element in the actuated state ensures a non-rotatable connection between the third element of the first planetary gear set and the second drive shaft, the rotor of the additional electric machine for the coupling with the first drive shaft can also be non-rotatable with the third Element of the first planetary gear set to be connected. In this case, the rotor of the additional electric machine is permanently coupled to the first drive shaft via the first planetary gear set. In this respect, the first planetary gear set acts as a pre-transmission between the first drive shaft and the rotor of the other electric machine. The rotor of the additional electric machine can be directly connected to the third element of the first planetary gear set in a torque-proof manner or can be coupled to it via one or more additional transmission stages.

According to a further embodiment of the invention, the first switching element and the fourth switching element are combined to form a switching device, to which an actuating element is assigned. In this case, on the one hand the first switching element and on the other hand the fourth switching element can be actuated via the actuating element from a neutral position. This has the advantage that the number of actuating elements and thus also the production costs can be reduced by combining them.

As an alternative or in addition to the aforementioned variant, the second switching element and the third switching element are combined to form a switching device, to which an actuating element is assigned. This actuating element can be used to actuate the second shifting element on the one hand and the third shifting element on the other hand from a neutral position. As a result, the production costs can be reduced by combining the two switching elements into one switching device, in that one actuating device can be used for both switching elements.

However, the two aforementioned shifting devices are particularly preferably implemented simultaneously, so that the five shifting elements of the transmission can be actuated via three actuating elements. As a result, a particularly low production cost can be achieved.

Within the scope of the invention, the transmission can be preceded by a starting element, for example a hydrodynamic torque converter or a friction clutch. This starting element can then also be part of the transmission and is used to design a starting process by enabling a slip speed between the engine, which is designed in particular as an internal combustion engine, and the first drive shaft of the transmission. In this case, one of the shifting elements of the transmission can also be designed as such a starting element, in that it is present as a friction shifting element. In addition, a freewheel to the transmission housing or to another shaft can in principle be arranged on each shaft of the transmission.

The transmission according to the invention is in particular part of a motor vehicle drive train for a hybrid or electric vehicle and is then arranged between a drive motor of the motor vehicle designed as an internal combustion engine or as an electric machine and other components of the drive train following in the direction of power flow to the drive wheels of the motor vehicle. The first drive shaft of the transmission is either permanently coupled in a rotationally fixed manner to a crankshaft of the internal combustion engine or the rotor shaft of the electric machine or can be connected to it via an intermediate starting element, with a torsional vibration damper also being able to be provided between an internal combustion engine and the transmission. On the output side, the transmission within the motor vehicle drive train is then preferably coupled to a differential gear of a drive axle of the motor vehicle, although here there can also be a connection to a longitudinal differential, via which distribution to several driven axles of the motor vehicle takes place. The differential gear or the longitudinal differential can be arranged with the gear in a common housing. A torsional vibration damper that may be present can also be integrated into this housing.

That two components of the transmission are "connected" or "coupled" or "interconnected". Connected”, in the sense of the invention, means a permanent coupling of these components, so that they cannot rotate independently of each other. In this respect, no switching element is provided between these components, which can be elements of the planetary gear sets and/or shafts and/or a non-rotatable component of the transmission, but the corresponding components are coupled to one another with a constant speed dependency.

If, on the other hand, a switching element is provided between two components, these components are not permanently coupled to one another, but coupling is only effected by actuating the switching element lying between them. An actuation of the switching element in the sense of the invention means that the relevant switching element is transferred to a closed state and as a result the components directly connected to it are adjusted to one another in terms of their rotational movements, if necessary. If the shifting element in question is designed as a positive shifting element, the components connected directly to one another in a rotationally fixed manner will run at the same speed, while in the case of a non-positive shifting element, there may be speed differences between the components even after it has been actuated. Within the scope of the invention, this desired or also undesired state is nevertheless referred to as a non-rotatable connection of the respective components via the switching element.

The invention is not limited to the specified combination of features of the main claim or the claims dependent thereon. In addition, there are possibilities of combining individual features with one another, even if they emerge from the claims, the following description of preferred embodiments of the invention or directly from the drawings. Reference of the claims to the drawings by the use of reference signs is not intended to limit the scope of the claims.

• 1 eine schematische Ansicht eines Kraftfahrzeugantriebsstranges entsprechend einer ersten Ausgestaltungsmöglichkeit der Erfindung;
• 2 bis 8 jeweils eine schematische Darstellung je einer erfindungsgemäßen Ausführungsform eines Getriebes, wie es bei dem Kraftfahrzeugantriebsstrang aus 1 Anwendung finden kann;
• 9 eine schematische Ansicht eines Kraftfahrzeugantriebsstranges gemäß einer zweiten Ausführungsform der Erfindung;
• 10 bis 16 jeweils eine schematische Darstellung je einer erfindungsgemäßen Ausgestaltungsmöglichkeit eines Getriebes, wie es bei dem Kraftfahrzeugantriebsstrang aus 9 zur Anwendung kommen kann;
• 17 ein beispielhaftes Schaltschema der Getriebe aus den 2 bis 8 und 10 bis 16; und
• 18 und 19 jeweils eine schematische Darstellung je einer Abwandlungsmöglichkeit der Getriebe aus den 2 bis 8 und 10 bis 16.

Advantageous embodiments of the invention, which are explained below, are shown in the drawings. It shows:

• 1 a schematic view of a motor vehicle drive train according to a first embodiment of the invention;
• 2 until 8th each a schematic representation of each embodiment of a transmission according to the invention, as in the motor vehicle drive train 1 can find application;
• 9 a schematic view of a motor vehicle drive train according to a second embodiment of the invention;
• 10 until 16 in each case a schematic representation of one possible embodiment of a transmission according to the invention, as is the case with the motor vehicle drive train 9 may apply;
• 17 an exemplary shift pattern of the transmission from the 2 until 8th and 10 until 16 ; and
• 18 and 19 each a schematic representation of a possible modification of the transmission from the 2 until 8th and 10 until 16 .

1 shows a schematic view of a motor vehicle drive train 1 of a hybrid vehicle, which is in particular a passenger car. In this case, in the motor vehicle drive train 1 , a drive machine 2 in the form of an internal combustion engine is connected to a transmission 4 via an intermediate torsional vibration damper 3 . A differential gear 5 is connected downstream of the gear 4 on the output side, via which a drive power is distributed to drive wheels 6 and 7 of a drive axle of the hybrid vehicle. The gear 4 and the torsional vibration damper 5 are combined in a common gear housing 8 of the gear 4, in which the differential gear 5 can then also be integrated. As also in 1 it can be seen that the drive motor 2, the torsional vibration damper 3, the transmission 4 and also the differential gear 5 are aligned transversely to a direction of travel of the hybrid vehicle.

Out of 2 shows a schematic representation of the transmission 4, which is designed according to a first embodiment of the invention. As can be seen, the transmission 4 includes a wheel set 9 and an electric machine 10 which are arranged together in the transmission housing 8 of the transmission 4 . The gear set 9 comprises two planetary gear sets 11 and 12, each of the planetary gear sets 11 and 12 having a first element 13 or 14, a second element 15 or 16, and a third element 17 or 18. The respective first element 13 or 14 is formed by a respective sun gear of the respective planetary gear set 11 or 12, while the respective second element 15 or 16 of the respective planetary gear set 11 or 12 acts as a planet carrier and the respective third element 17 or 18 of the respective planetary gear set 11 or 12 is present as a ring gear.

The two planetary gear sets 11 and 12 are therefore each present as a minus planetary gear set, in which the respective planet carrier has at least one Pla netenrad rotatably mounted, which is in mesh with both the respective, radially inner sun gear, and with the respective, radially surrounding ring gear. However, in the case of the first planetary gearset 11 and the second planetary gearset 12, a plurality of planetary gears are particularly preferably provided in each case.

Alternatively, however, one of the planetary gear sets 11 and 12 or both planetary gear sets 11 and 12 could each be designed as a plus planetary gear set, provided a connection of the respective elements 13, 15 and 17 or 14, 16 and 18 allows this. In a plus planetary gear set, the respective planetary carrier carries at least one pair of planetary gears, one of whose planetary gears meshes with the respective, radially inner sun gear and a planetary gear with the respective, radially surrounding ring gear, and the planetary gears mesh with one another. In comparison to the design as a negative planetary gear set, the respective second element of the respective planetary gear set is then formed by the ring gear and the respective third element is formed by the planet carrier and a gear ratio of the respective planetary gear set is increased by one.

The transmission 4 comprises a first input shaft 19, a second input shaft 20 and an output shaft 21 which are arranged coaxially with one another and also with the two planetary gear sets 11 and 12. The first drive shaft 19 is embodied as a solid shaft and terminates at a connection point 22 within the motor vehicle drive train 1 1 connected to the torsional vibration damper 3, so that the first drive shaft 19 is permanently coupled to the engine 2 within the motor vehicle drive train 1. In contrast, the second input shaft 20 and the output shaft 21 are each designed as hollow shafts, which are each placed radially surrounding the first input shaft 19 and each axially overlap with a partial section of the first input shaft 19 .

As in 2 can be seen, the electric machine 10 is composed of a stator 23 and a rotor 24 . The stator 23 of the electric machine 10 is permanently fixed to the transmission housing 8 of the transmission 4, the stator 23 being able to be connected directly to the transmission housing 8 or to a part of the transmission housing 8 or to a component connected thereto in a rotationally fixed manner. The electric machine 10 is arranged coaxially to the second drive shaft 20, the rotor 24 of the electric machine 10 being non-rotatably connected to the second drive shaft 20 in that a rigid connection is formed between the rotor 24 and the second drive shaft 20. The electric machine 10 can be operated on the one hand as a generator and on the other hand as an electric motor.

The output shaft 21 is permanently connected at a connection point 25 to the differential gear 5 following in the motor vehicle drive train 1, whereby this connection can be realized in particular via a spur gear stage, one of the spur gears of which is placed on the output shaft 21 in a rotationally fixed manner and the connection point on external teeth 25 of the output shaft 21 forms. In this respect, via the connection point 25 of the output shaft 21 within the motor vehicle drive train 1 in 1 a lateral output on the differential gear 5.

As in 2 As can be seen, the transmission 4 comprises a total of five shifting elements A, B, C, D and E. The shifting elements A, B, C, D and E are each designed as positive shifting elements and are preferably present as claw shifting elements. In addition, the shifting elements A, B, C and D are presently designed as clutches, while the shifting element E is designed as a brake.

The first input shaft 19 of the transmission 4 is non-rotatably connected to the second element 15 of the first planetary gear set 11, while the second input shaft 20 is non-rotatably connected to the rotor 24 of the electric machine 10 and is also non-rotatably connected to the first element 14 of the second planetary gear set 12 and the third element 17 of the first planetary gear set 11 is connected. The non-rotatable connection with the third element 17 of the first planetary gear set 11 is produced indirectly via the intermediate rotor 24 of the electric machine 10 . Furthermore, the third element 18 of the second planetary gear set 12 is permanently fixed to the transmission housing 8 in that the third element 18 is directly non-rotatably connected to the transmission housing 8 or to a part of the transmission housing 8 or to a component connected non-rotatably thereto.

The first drive shaft 19 can be connected in a rotationally fixed manner to the output shaft 21 by closing the shifting element B, whereby the first drive shaft 19 can also be connected in a rotationally fixed manner to the second drive shaft 20 via the shifting element C, which, due to the associated rotationally fixed connection between the second element 15 of the first planetary gear set 11 and the third element 17 of the first planetary gear set 11 has a blocking of the first planetary gear set 11 result. Closing the switching element A results in a non-rotatable connection of the output shaft 21 with the second element 16 of the second planetary gear set 12, the output shaft 21 also being non-rotatably connected to the second drive via the switching element D shaft 20 can be connected. Finally, the first element 13 of the first planetary gear set 11 can also be fixed to the transmission housing 8 by means of the shifting element E, whereby this can be realized by a direct non-rotatable connection to the transmission housing 8 or to a part of the transmission housing 8 or also to a component connected non-rotatably thereto .

The connection point 22 of the first drive shaft 19 is configured at an axial end of the transmission 4, the connection point 25 of the output shaft 21 being aligned axially adjacent thereto and transversely. Axially on the connection point 25 of the output shaft 21 then follows first the second planetary gear set 12, on the side facing away from the connection point 25 axially the first planetary gear set 11 and the electric machine 10 are provided. The electric machine 10 and the first planetary gear set 11 are axially at the same height, with the first planetary gear set 11 being provided radially on the inside of the electric machine 10 .

How also from 2 As can be seen, the shifting element B, the shifting element C and the shifting element D are arranged axially between the connection point 22 of the first drive shaft 19 and the connection point 25 of the output shaft 21, whereby first the shifting element B, then the shifting element C and finally the Follow switching element D axially. In contrast, the switching element A is placed axially between the connection point 25 of the output shaft 21 and the second planetary gear set 12 .

In the present case, the shifting elements B and C are arranged axially directly next to one another and radially at essentially the same height and have a common actuating element - not shown here - via which either the shifting element B or the shifting element C can be actuated from a neutral position. In this respect, the switching elements B and C are combined to form a switching device 26 .

Likewise, shifting elements A and D are placed axially directly next to one another and radially at essentially the same height and are combined to form a shifting device 27, in that an actuating element - also not shown in detail - is provided, via which either shifting element D or the Switching element A can be operated.

In contrast, the shifting element E is provided in the area of an axial end of the transmission 4 , which is opposite to the axial end having the connection point 22 of the first drive shaft 19 .

Furthermore shows 3 a schematic representation of a transmission 4 ', which is designed according to a second embodiment of the invention and also in the motor vehicle drive train 1 in 1 can be applied. In this case, this transmission 4 ′ corresponds essentially to the transmission 4 2 , with the difference that in the case of a wheel set 9' of the transmission 4', the first element 13 of the first planetary gear set 11 is constantly connected in a rotationally fixed manner to the transmission housing 8, a part of the transmission housing 8 or a component connected thereto in a rotationally fixed manner and is therefore permanently fixed . Furthermore, the third element 17 of the first planetary gear set 11 is not permanently connected in a rotationally fixed manner to the rotor 24 of the electric machine 10 and thus also to the second drive shaft 20 and the first element 14 of the second planetary gear set 12, but a rotationally fixed connection is only established by actuating the shifting element E educated. In this respect, the switching element E is implemented as a clutch in this case. For the rest, the design corresponds to 3 according to the variant 2 , so that reference is made to what has been described here.

Out of 4 shows a schematic view of a transmission 4" according to a third embodiment of the invention, which is an alternative to the transmission 4 2 in the automotive powertrain 1 in 1 can find application. This gear 4" essentially corresponds to the variant 2 , where in contrast to the gear 4 from 2 in a wheel set 9" of the transmission 4", the first element 13 of the first planetary gear set 11 is constantly connected in a rotationally fixed manner to the transmission housing 8 and is thus permanently fixed. Furthermore, the second element 15 of the first planetary gear set 11 is now not permanently non-rotatably connected to the first drive shaft 19 , but is only non-rotatably connected to the first drive shaft 19 when the shifting element E is actuated. The shifting element E is designed as a clutch and is provided axially between the second planetary gearset 12 and the first planetary gearset 11 . In particular, the shifting element E is located axially at the level of the electric machine 10 and radially on the inside of the latter. Otherwise, the embodiment corresponds to 4 according to the variant 2 , so that reference is made to what has been described here.

In addition, shows 5 a schematic representation of a transmission 4''', which is designed according to a fourth possible embodiment of the invention and also in the motor vehicle g drive train 1 in 1 can be applied. This configuration option largely corresponds to the variant 2 In contrast to this, the transmission 4''" also has a further electric machine 28, which is composed of a stator 29 and a rotor 30. The further electric machine 28 is placed coaxially with the drive shafts 19 and 20 and also the output shaft 21 and can be operated on the one hand as an electric motor and on the other hand as a generator.While the stator 29 of the electric machine 28 is permanently fixed to the gear housing 8, the rotor 30 is directly connected in a rotationally fixed manner to the first drive shaft 19, whereby the additional electric machine 28 when the gear 4' is used " within the automotive powertrain 1 in 1 is permanently coupled to the upstream drive machine 2. The further electric machine 28 is provided axially within the transmission 4′″ between the connection point 22 of the first drive shaft 19 and the connection point 25 of the output shaft 21. Otherwise the embodiment corresponds to FIG 5 according to the variant 2 , so that reference is made to what has been described here.

Out of 6 shows a schematic view of a transmission 4 ^IV , which is realized according to a fifth possible embodiment of the invention and also instead of the transmission 4 from FIG 2 in the automotive powertrain 1 in 1 can find application. This design option largely corresponds to the variant 3 , with the only difference that an additional electric machine 28 is provided. The additional electric machine 28 is analogous to the previous variant 5 arranged. Accordingly, a stator 29 of the electric machine 28 is permanently fixed to the transmission housing 8, while the rotor 30 of the electric machine 28 is directly connected to the first drive shaft 19 in a rotationally fixed manner. The electric machine 28 provided coaxially to the first drive shaft 19 can be operated as a generator on the one hand and as an electric motor on the other. For the rest, the embodiment corresponds to 6 according to the variant 3 , so that reference is made to what has been described here.

Furthermore shows 7 a schematic representation of a transmission 4 ^V , which is designed according to a sixth embodiment of the invention and as an alternative to the transmission 4 in the motor vehicle drive train 1 in 1 can be applied. This embodiment essentially corresponds to the previous variant 6 , the difference being that the rotor 30 of the further electric machine 28 is directly connected in a rotationally fixed manner to the third element 17 of the first planetary gear set 11 . As a result, the rotor 30 of the additional electric machine 28 is permanently coupled to the first drive shaft 19 via the first planetary gear set 11, since the first element 13 of the first planetary gear set 11 is permanently fixed and the second element 15 of the first planetary gear set 11 is constantly non-rotatably connected to the first drive shaft 19 is. The first planetary gear set 11 acts as a pre-transmission for coupling the additional electric machine 28 to the first drive shaft 19. The additional electric machine 28 is placed axially at the level of the first planetary gear set 11, with the first planetary gear set 11 being arranged radially on the inside of the additional electric machine 28 is. In contrast, the electric machine 10 is now located axially at the level of the second planetary gear set 12, which is placed radially on the inside of the electric machine 10. Furthermore, the shifting element E is now located axially between the first planetary gearset 11 and the second planetary gearset 12. Finally, the connection point 25 of the output shaft 21 is provided axially at the level of the shifting element B and axially adjacent to the connection point 22 of the first input shaft 19, while the other Switching elements C, D and A are located axially between the connection point 25 and the second planetary gear set 12 . Otherwise, the embodiment corresponds to 7 according to the variant 6 , so that reference is made to what has been described here.

Out of 8th shows a schematic view of a transmission 4 ^VI , this transmission 4 ^VI is designed according to a seventh embodiment of the invention and instead of the transmission 4 from 2 in the automotive powertrain 1 in 1 can be used. This embodiment essentially corresponds to the variant 4 , whereby as a difference, as with the variants after 5 and 6 , In addition, a further electric machine 28 is provided. This electric machine 28 is placed coaxially to the first drive shaft 19, with a stator 29 of the electric machine 28 being permanently fixed to the transmission housing 8, whereas a rotor 30 of the electric machine 28 is permanently connected to the first drive shaft 19 in a torque-proof manner. The electric machine 28 is placed axially between the connection point 22 of the first drive shaft 19 and the connection point 25 of the output shaft 21 . Otherwise, the embodiment corresponds to 8th according to the variant 4 , so that reference is made to what has been described here.

9 shows a schematic view of an alternative embodiment of a motor vehicle drive train 1 ', which is also designed as a drive train for a hybrid vehicle in the form of a car. This motor vehicle drive train 1′ also includes a drive machine 2, which is preferably designed as an internal combustion engine is performed and is connected via a torsional vibration damper 3 with a gear 4 ^VII . As in the case of the motor vehicle drive train 1, the transmission 4 ^VII is off 1 , A differential gear 5 is connected downstream on the output side, via which drive power is distributed to drive wheels 6 and 7 of a drive axle of the hybrid vehicle. Again, the gear 4 ^VII and the torsional vibration damper 5 are combined in a common gear housing 8 of the gear 4 ^VII , in which the differential gear 5 can also be integrated. Different from the variant after 1 is, however, that the prime mover 2, the torsional vibration damper 3, the gear 4 ^VII and also the differential gear 5 are aligned in the direction of travel of the hybrid vehicle.

Out of 10 shows a schematic detail view of the transmission 4 ^VII , which is realized according to an eighth embodiment of the invention. This embodiment largely corresponds to the transmission 4 2 , by ^having a first input shaft 19', a second input shaft 20', an output shaft 21', an electric machine 10 and components of the planetary gear sets 11 and 12 analogously to the variant according to FIG 2 are connected to one another or can be connected or fixed in an analogous manner via the switching elements A, B, C, D and E. Due to the orientation of the motor vehicle drive train 1 ' 9 in the direction of travel of the hybrid vehicle, however, components of the wheel set 9''' are now arranged differently. Thus, a connection point 25' of the output shaft 21' is provided at an axial end which is opposite to the axial end at which the connection point 22 of the first drive shaft 19' is provided. The output shaft 21' is also designed as a solid shaft, which is placed coaxially with the first drive shaft 19', which is also designed as a solid shaft, with the second drive shaft 20' being provided as a hollow shaft, radially surrounding the output shaft 21' and axially with a partial section of the output shaft 21' covered.

Axially following the connection point 22 of the first drive shaft 19 ′ is first the first planetary gear set 11 , which is still arranged axially with the electric machine 10 essentially at the same level and radially on the inside of the electric machine 10 . The second planetary gearset 12 is then provided axially on a side of the first planetary gearset 11 facing away from the connection point 22 and lies axially between the first planetary gearset 11 and the connection point 25′ of the output shaft 21′. Of the shifting elements A, B, C, D and E, the shifting elements D and A are arranged axially between the second planetary gear set 12 and the connection point 25 ′ and are still combined to form a shifting device 27 . The shifting device 26, consisting of the shifting elements B and C, is located axially between the first planetary gearset 11 and the second planetary gearset 12, the shifting device 26 being provided axially at the level of the electric machine 10 and radially on the inside of the latter. The remaining shifting element E is placed axially between the connection point 22 of the first drive shaft 19 ′ and the first planetary gearset 11 . For the rest, the embodiment corresponds to 10 according to the variant 2 , so that reference is made to what has been described here.

Furthermore shows 11 a schematic representation of a transmission 4 ^VIII , which is designed according to a ninth possible embodiment of the invention and as an alternative to the transmission 4 ^VII in the motor vehicle drive train 1' 9 can be applied. The transmission 4 ^VIII essentially corresponds to the variant 10 , with the difference that in a wheel set 9 ^IV of the transmission 4 ^VIII , the first element 13 of the first planetary gear set 11 is now permanently non-rotatably connected to the transmission housing 8, a part of the transmission housing 8 or a component non-rotatably connected thereto and is thus permanently fixed . Furthermore, the third element 17 of the first planetary gear set 11 is not permanently connected in a rotationally fixed manner to the rotor 24 of the electric machine 10 and thus also to the second drive shaft 20 and the first element 14 of the second planetary gear set 12, but a rotationally fixed connection is only established by actuating the shifting element E educated. In this respect, the switching element E is implemented as a clutch in this case. For the rest, the design corresponds to 11 according to the variant 10 , so that reference is made to what has been described here.

Furthermore goes out 12 shows a schematic view of a transmission 4 ^IX according to a tenth embodiment of the invention, which is alternative to the transmission 4 ^VII from 10 in the motor vehicle drive train 1' in 9 can be applied. This gear 4 ^IX also largely corresponds to the variant 10 In contrast to this, in a wheel set 9 ^V of the transmission 4 ^IX , the first element 13 of the first planetary gear set 11 is constantly connected in a rotationally fixed manner to the transmission housing 8 and is thus permanently fixed. Furthermore, the second element 15 of the first planetary gear set 11 is now not permanently non-rotatably connected to the first drive shaft 19 ′, but is only non-rotatably connected to the first drive shaft 19 ′ by actuating the shifting element E. The switching element E is designed as a clutch and axially between the first planetary gear set 11 and the second plane tenradsatz 12 is provided, wherein the switching element E is specifically provided axially between the first planetary gear set 11 and the switching device 26. In this case, the switching element E is located axially at the level of the electric machine 10 and radially on the inside of the latter. Otherwise, the embodiment corresponds to 12 according to the variant 10 , so that reference is made to what has been described here.

In addition, shows 13 a schematic representation of a transmission 4 ^X , which is designed according to an eleventh possible embodiment of the invention and also in the motor vehicle drive train 1 'in 9 can be applied. This configuration option largely corresponds to the variant 10 In contrast to this, the transmission 4 ^X additionally has a further electric machine 28 which is composed of a stator 29 and a rotor 30 . The additional electric machine 28 is placed coaxially to the drive shafts 19' and 20' and also the output shaft 21' and can be operated as an electric motor on the one hand and as a generator on the other. The stator 29 of the electric machine 28 is permanently fixed to the transmission housing 8, while the rotor 30 is directly non-rotatably connected to the first drive shaft 19', whereby the further electric machine 28 when the transmission 4 ^X is used within the motor vehicle drive train 1' in 9 is permanently coupled to the upstream drive machine 2. The additional electric machine 28 is provided axially within the transmission 4 ^X between the connection point 22 of the first drive shaft 19 ′ and the first planetary gear set 11 . Otherwise, the embodiment corresponds to 13 according to the variant 10 , so that reference is made to what has been described here.

Also goes out 14 shows a schematic view of a transmission 4 ^XI , which is designed according to a twelfth embodiment of the invention and also instead of the transmission 4 ^VII 10 in the motor vehicle drive train 1' in 9 can find application. This design option largely corresponds to the variant 11 , with the only difference that a further electric machine 28 is also provided here. Similar to the previous variant 13 a stator 29 of the electric machine 28 is permanently fixed to the transmission housing 8, while the rotor 30 of the electric machine 28 is directly non-rotatably connected to the first drive shaft 19'. The electric machine 28 provided coaxially to the first drive shaft 19 can be operated in a generator mode on the one hand and in an electric motor mode on the other. For the rest, the embodiment corresponds to 14 according to the variant 11 , so that reference is made to what has been described here.

Furthermore shows 15 a schematic representation of a transmission 4 ^XII , which is designed according to a thirteenth embodiment of the invention and as an alternative to the transmission 4 ^VII in the motor vehicle drive train 1 'in 9 can be applied. This embodiment largely corresponds to the previous variant 14 , the difference being that the rotor 30 of the further electric machine 28 is now directly connected in a rotationally fixed manner to the third element 17 of the first planetary gear set 11 . As a result, the rotor 30 of the additional electric machine 28 is permanently coupled to the first drive shaft 19' via the first planetary gear set 11, since the first element 13 of the first planetary gear set 11 is permanently fixed and the second element 15 of the first planetary gear set 11 is constantly non-rotatably connected to the first drive shaft 19 ' connected is. In this respect, the first planetary gear set 11 functions as a pre-transmission for coupling the additional electric machine 28 to the first drive shaft 19'. The additional electric machine 28 is placed axially at the level of the first planetary gear set 11 , with the first planetary gear set 11 being arranged radially on the inside of the additional electric machine 28 . In contrast, the electric machine 10 is now located axially at the level of the second planetary gear set 12, which is placed radially on the inside of the electric machine 10. Furthermore, the shifting element E is now placed axially between the first planetary gear set 11 and the second planetary gear set 12 . Otherwise, the embodiment corresponds to 15 according to the variant 14 , so that reference is made to what has been described here.

Finally goes out 16 shows a schematic view of a transmission 4 ^XIII , this transmission 4 ^XIII being designed according to a fourteenth embodiment of the invention and instead of the transmission 4 ^VII 10 in the motor vehicle drive train 1' in 9 can be used. This embodiment essentially corresponds to the variant 12 , whereby as a difference, as with the variants after 13 and 14 , In addition, a further electric machine 28 is provided. This electric machine 28 is placed coaxially to the first drive shaft 19', with a stator 29 of the electric machine 28 being permanently fixed to the transmission housing 8, whereas a rotor 30 of the electric machine 28 is constantly non-rotatably connected to the first drive shaft 19'. The electric machine 28 is placed axially between the connection point 22 of the first drive shaft 19 ′ and the first planetary gear set 11 . Otherwise, the embodiment corresponds to 16 according to the variant 12 , so that reference is made to what has been described here.

In 17 is an exemplary shift pattern for the transmissions 4 to 4 ^XIII from the 2 until 8th and 10 until 16 tabulated. As can be seen, a total of four gears V1 to V4 can be implemented between the first drive shaft 19 or 19' and the output shaft 21 or 21', with an X in the columns of the shift pattern indicating which of the shifting elements A, B, C, D and E in which of the gears V1 to V4 is closed. In each of the gears V1 to V4, two of the shifting elements A, B, C, D and E are closed.

As in 17 can be seen, a first gear V1 is shifted between the first input shaft 19 or 19' and the output shaft 21 or 21' by actuating shifting element A and shifting element C, with a second gear V2 being shifted between the first drive shaft 19 or 19 'and the output shaft 21 or 21' by closing the switching element A and the switching element E results. A third gear is then produced in a first variant V3.1 between the first input shaft 19 or 19' and the output shaft 21 or 21' by closing the shifting elements A and B. The third gear can also be activated in a second variant V3.2 by actuating the shifting element B and the shifting element D, in a third variant V3.3 by closing the shifting element B and the shifting element E, in a fourth variant V3.4 by actuating the shifting element C and the switching element D and in a fifth variant V3.5 by closing the switching element B and the switching element C are switched. Furthermore, a fourth gear V4 results between the first input shaft 19 or 19' and the output shaft 21 or 21' by actuating the shifting elements D and E.

In the case of transmissions 4 to 4 ^XIII , purely electric operation can also be implemented via the electric machine 10: purely electric driving can take place in a first gear E1, which is located between the second input shaft 20 or 20' and the output shaft 21 or 21 'Is effective and for the representation of which the switching element A is to be converted into a closed state, as shown in FIG 17 emerges. When the shifting element A is closed, the electric machine 10 is connected to the output shaft 21 or 21′ via the second planetary gear set 12 with a constant transmission ratio, the transmission ratio of the first gear E1 corresponding to the transmission ratio of the first gear V1.

Advantageously, starting from the first gear E1, the upstream drive machine 2 can be started in one of the gears V1, V2 or V3.1, since the shifting element A is closed in each of these gears. In this respect, a transition can be made quickly from purely electric driving to purely driving via the drive machine 2 . Conversely, since the electric machine 10 is also involved when driving in the gears V1, V2 and V3.1, an additional drive torque can be selectively fed in via the electric machine 10 in one of the gears V1, V2 and V3.1 in its electric motor operation become. In addition, the electric machine 10 can be used in its generator mode for braking the motor vehicle.

In addition, a second gear E2 for purely electric operation can also be shifted between the second input shaft 20 or 20' and the output shaft 21 or 21', for which purpose the shifting element D must be actuated. As a result, the second drive shaft 20 or 20' is directly non-rotatably connected to the output shaft 21 or 21', so that a direct through drive from the second drive shaft 20 or 20' to the output shaft 21 or 21' can take place. A translation of this gear corresponds to a translation of the third gear effective between the first input shaft 19 or 19' and the output shaft 21 or 21'.

Starting from the gear E2, the upstream drive machine 2 can be started in one of the gears V3.2, V3.4 and V4, since the shifting element D is also actuated in each of these. In this respect, it is also possible here to quickly switch from purely electric driving to purely driving via the drive machine 2 . In addition, in one of the gears V3.2, V3.4 and V4, the electric machine 10 can selectively feed in an additional drive torque in its electromotive operation or in its generator operation ensure that the motor vehicle is braked.

The gears E1 and E2 can each be used for purely electric driving, in which case, depending on the direction of rotation initiated via the electric machine 10, forward travel or reverse travel can be represented. In addition, when the electric machine 10 is operated as a generator, the motor vehicle can be braked in a targeted manner while generating electricity (recuperation).

Although the shifting elements A, B, C, D and E are each designed as positive shifting elements, a respective shift between the first gear V1 and the second gear V2, between the second gear V2 and the first variant V3.1 of the third gear as well as be realized under load between the second variant 3.2 of the third gear and the fourth gear V4. The reason for this is that the switching element A on the gears V1, V2 and V3.1 and the switching element D on the Gears V3.2 and V4 is involved, so that in the course of switching the output can be supported via the electric machine EM. In the third gear, switching between the two variants V3.1 and V3.2 must be carried out. The shifts can be synchronized by appropriate control of the upstream internal combustion engine ICE, so that the shift element to be designed can be opened without load and the shift element to be closed subsequently can be closed without load.

Furthermore, by closing the switching element C, a charging or starting function can be implemented. Because when the switching element C is closed, the electric machine 10 is directly coupled in a torque-proof manner to the first drive shaft 19 or 19' and thus also to the drive motor 2. At the same time, however, there is no frictional connection to the output shaft 21 or 21', with the first drive shaft 19 or 19' and the second drive shaft 20 or 20' run at the same speed. When the electric machine 10 is operating as a generator, an electrical energy store can be charged via the drive machine 2 , while when the electric machine 10 is operated as an electric motor, the drive machine 2 can be started via the electric machine 10 .

A charging or starting function can also be implemented when the switching element E is in the closed state, in which the first drive shaft 19 or 19′ and the second drive shaft 20 or 20′ are coupled to one another via the first planetary gear set 11 . Here, too, an electrical energy storage device can be charged via the drive machine 2 when the electric machine 10 is operated as a generator, whereas in the electric motor mode of the electric machine 10 the drive machine 2 can be started via the electric machine 10 .

Finally, the speed of electric machine 10 can be reduced in mechanical or hybrid operation: after a torque-assisted shift from gear V2 to gear V3.1 via electric machine 10 or after starting drive machine 2 into gear V3.1, a hybrid driving in gear V3.1. In order to lower the speed of the electric machine 10 in third gear at higher driving speeds, it is possible to switch from the first variant V3.1 of the third gear to the second variant V3.2 of the third gear, in which the rotor 24 has a lower speed. This switchover takes place while maintaining the traction via the drive motor 2. For this purpose, the then no-load shifting element A is designed and the likewise no-load shifting element D is engaged, with the speed adjustment taking place in each case by speed control of the electric machine 10.

If the additional electric machine 28 is also provided, this electric machine 28 can be used at any time due to its permanent coupling to the upstream drive machine 2 to start the drive machine 2 or to generate electricity in the generator mode of the electric machine 28 . In the latter case, serial operation can also be implemented in this way, in which the additional electric machine 28 generates electricity by being driven by the drive machine 2, which electric machine 10 uses for purely electric driving in one of the gears E1 or E2.

Finally show the 18 and 19 Possible modifications of the transmissions 4 to 4 ^XIII with regard to the integration of the electric machine 10. The electric machine 10 is no longer arranged coaxially to the second drive shaft 20 or 20', but is offset from the axis of the second drive shaft 20 or 20'.

A coupling is in the case of the variant after 18 carried out via two transmission stages, which are realized as spur gear stages 31 and 32. The second drive shaft 20 or 20 'carries a spur gear 33 of the first spur gear 31, the spur gear 33 is permanently in mesh with an intermediate gear 34 and forms the first spur gear 31 together with this. The intermediate gear 34 is also part of the spur gear stage 32 in that it also meshes with a further spur gear 35 of the spur gear stage 32 in addition to the spur gear 33 . The spur gear 35 is then provided on a rotor shaft 36 of the electric machine 10 in a rotationally fixed manner.

Even with the possibility of modification 19 the second drive shaft 20 or 20 ′ is coupled to the rotor shaft 36 , which is offset from the axis, of the electric machine 10 , this being implemented in this case via a transmission stage in the form of a traction drive 37 . This traction drive 37 is in particular a chain drive.

The possible modifications 18 and 19 can also be used in an analogous manner for an off-axis connection of the additional electric machine 28 to the first drive shaft 19 or 19 ′ or to the third element 17 of the first planetary gear set 11 .

By means of the configurations according to the invention, a transmission with a compact design and a high level of efficiency can be implemented.

Reference List

1.1'

automotive powertrain

2

prime mover

3

torsional vibration damper

4 to 4XIII

transmission

5

differential gear

6

drive wheel

7

drive wheel

8th

gear case

9 to 9V

wheelset

10

electric machine

11

First planetary gear set

12

Second planetary gear set

13

first element first planetary gear set

14

first element second planetary gear set

15

second element first planetary gear set

16

second element second planetary gear set

17

third element first planetary gear set

18

third element second planetary gear set

19, 19'

First driveshaft

20, 20'

Second drive shaft

21, 21'

output shaft

22

junction

23

stator

24

rotor

25, 25'

junction

26

switching device

27

switching device

28

electric machine

29

stator

30

rotor

31

spur gear stage

32

spur gear stage

33

spur gear

34

intermediate wheel

35

spur gear

36

rotor shaft

37

traction drive

V1 to V4

gears

E1 and E2

gears

A

switching element

B

switching element

C

switching element

D

switching element

E

switching element

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• DE 102013013947 A1 [0003]

Claims (17)

Transmission (4 to 4 ^XIII ) for a motor vehicle, comprising an electric machine (10), a first drive shaft (19; 19'), a second drive shaft (20; 20'), an output shaft (21; 21'), and a first Planetary gear set (11) and a second planetary gear set (12), the first drive shaft (19; 19') being set up to connect the transmission (4 to 4 ^XIII ) to a drive engine (2) of the motor vehicle, the planetary gear sets (11 , 12) each have a first element (13, 14), a second element (15, 16) and a third element (17, 18), wherein a first (A), a second (B), a third (C), a fourth (D) and a fifth switching element (E) are provided, and wherein a rotor (24) of the electric machine (10) is connected to the second drive shaft (20; 20'), characterized in that - that the second drive shaft (20; 20') is non-rotatably connected to the first element (14) of the second planetary gear set (12), - that the third element (18) de s second planetary gear set (12) is fixed - that the output shaft (21; 21') via the first switching element (A) can be connected in a rotationally fixed manner to the second element (16) of the second planetary gear set (12) and can be connected in a rotationally fixed manner to the first drive shaft (19; 19') by means of the second shifting element (B), - that the first drive shaft (19; 19') can be connected in a rotationally fixed manner to the second drive shaft (20; 20') via the third shifting element (C), - that the second drive shaft (20; 20') can be connected by means of the fourth shifting element (D ) can be connected in a torque-proof manner to the output shaft (21; 21'), - and that in the first planetary gear set (11) a first coupling of the first element (13) of the first planetary gear set (11) with a torque-proof component, a second coupling of the second element (15) of the first planetary gear set (11) with the first drive shaft (19; 19') and a third coupling of the third element (17) of the first planetary gear set (11) with the second drive shaft (20; 20'), of which three couplings two as permanent non-rotatable connection present, while in the remaining coupling a non-rotatable connection by means of the fifth switching element (E) can be produced. Transmission (4; 4'"; 4 ^VII ; 4 ^X ) to claim 1 , characterized in that the second element (15) of the first planetary gear set (11) is non-rotatably connected to the first drive shaft (19; 19') and the third element (17) of the first planetary gear set (11) is non-rotatably connected to the second drive shaft (20 ; 20') is connected, whereas the first element (13) of the first planetary gear set (11) can be fixed to the non-rotatable component via the fifth switching element (E). Transmission (4; 4'"; 4 ^VII ; 4 ^X ) to claim 2 , characterized in that the third switching element (C) in the actuated state connects the second element (15) and the third element (17) of the first planetary gearset (11) to one another in a torque-proof manner or the first element and the second element of the first planetary gearset to one another in a torque-proof manner Connection brings or rotatably connects the first element and the third element of the first planetary gear set together. Transmission (4'; 4 ^IV ; 4 ^V ; 4 ^VIII ; 4 ^XI ; 4 ^XII ) according to claim 1 , characterized in that the first element (13) of the first planetary gear set (11) is fixed and the second element (15) of the first planetary gear set (11) is non-rotatably connected to the first drive shaft (19; 19'), whereas the third Element (17) of the first planetary gear set (11) can be connected to the second drive shaft (20; 20') in a torque-proof manner by means of the fifth shifting element (E). Transmission (4"; 4 ^VI ; 4 ^IX ; 4 ^XIII ) to claim 1 , characterized in that the first element (13) of the first planetary gear set (11) is fixed and the third element (17) of the first planetary gear set (11) is non-rotatably connected to the second drive shaft (20; 20'), whereas the second The element (15) of the first planetary gear set (11) can be connected in a torque-proof manner to the first drive shaft (19; 19') via the fifth shifting element (E). Transmission (4 to 4 ^XIII ) according to one of the preceding claims, characterized in that - a first gear (V1) between the first input shaft (19; 19') and the output shaft (21; 21') by actuating the first (A ) and the third shifting element (C), - a second gear (V2) between the first input shaft (19; 19') and the output shaft (21; 21') by engaging the first (A) and the fifth shifting element (E), - A third gear between the first input shaft (19; 19') and the output shaft (21; 21') in a first variant (V3.1) by closing the first (A) and the second switching element (B), in a second Variant (V3.2) by closing the second (B) and the fourth switching element (D), in a third variant (V3.3) by closing the second (B) and the fifth switching element (E), in a fourth variant ( V3.4) by actuating the third (C) and the fourth switching element (D) and in a fifth variant (V3.5) by actuating the second (B) and the third switching element (C), - and a fourth gear (V4) between the first drive shaft (19; 19') and the output shaft (21; 21') by closing the fourth (D) and the fifth switching element (E). Transmission (4 to 4 ^XIII ) according to one of the preceding claims, characterized in that - a first gear (E1) between the second input shaft (20; 20 ') and the output shaft (21; 21') by closing the first switching element ( A) - and a second gear (E2) between the second input shaft (20; 20') and the output shaft (21; 21') by actuating the fourth shifting element (D). Transmission (4 to 4 ^XIII ) according to one of the preceding claims, characterized in that one or more of the shifting elements (A, B, C, D, E) are each implemented as a positive-locking shifting element. Transmission (4 to 4 ^XIII ) according to one of the preceding claims, characterized in that the respective planetary gear set (11, 12) is designed as a negative planetary gear set, the respective first element (13, 14) of the respective planetary gear set (11 , 12) around a respective sun gear, in the respective second element (15, 16) of the respective planetary gear set (11, 12) around a respective planet carrier and in the respective third element (17, 18) of the respective planetary gear set (11, 12). a respective ring gear is. Transmission according to one of the preceding claims, characterized in that the respective planetary gear set is designed as a positive planetary gear set, the respective first element of the respective planetary gear set being a respective sun gear, the respective second element of the respective planetary gear set being a respective ring gear and the respective third element of the respective planetary gear set is a respective planet carrier. Transmission (4 to 4 ^XIII ) according to one of the preceding claims, characterized in that the rotor (24) of the electric machine (10) is rigidly connected to the second drive shaft (20; 20') or is connected to the second drive shaft ( 20; 20'). Transmission (4'''; 4 ^IV ; 4 ^V ; 4 ^VI ; 4 ^X ; 4 ^XI ; 4 ^XII ; 4 ^XIII ) according to one of the preceding claims, characterized in that a further electric machine (28) is also provided, whose rotor (30) is rigidly connected to the first drive shaft (19; 19') or coupled to the first drive shaft (19; 19') via at least one transmission stage. Transmission (4 ^V ; 4 ^XII ) after claim 4 and after claim 12 , characterized in that the rotor (30) of the further electric machine (28) is non-rotatably connected to the third element (17) of the first planetary gear set (11). Transmission (4 to 4 ^XIII ) according to one of the preceding claims, characterized in that the first shifting element (A) and the fourth shifting element (D) are combined to form a shifting device (27) which is assigned an actuating element, with the actuating element being a neutral position out on the one hand the first switching element (A) and on the other hand the fourth switching element (D) can be actuated. Transmission (4 to 4 ^XIII ) according to one of the preceding claims, characterized in that the second shifting element (B) and the third shifting element (C) are combined to form a shifting device (26), which is assigned an actuating element, with the actuating element being a neutral position out on the one hand the second switching element (B) and on the other hand the third switching element (C) can be actuated. Motor vehicle drive train (1; 1 ') for a hybrid or electric vehicle, comprising a transmission (4 to 4 ^XIII ) according to one or more of Claims 1 until 15 . Method for operating a transmission (4 to 4 ^XIII ) according to one of Claims 1 until 15 , characterized in that only the third switching element (C) or only the fifth switching element (E) is closed to represent a charging operation or a starting operation.

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