DE102018200296B4 - Transmission for a motor vehicle - Google Patents

Abstract

Transmission (G) for a motor vehicle, comprising an electric machine (EM), an input shaft (GW1), an output shaft (GWA), and a first planetary gear set (P1), a second planetary gear set (P2) and a third planetary gear set (P3), wherein the first, the second and the third planetary gear set (P1, P2, P3) each have a first element (E11, E12, E13), a second element each (E21, E22, E23) and a third element each (E31, E32, E33). ), wherein the first element (E11, E12, E13) is formed by a respective sun gear of the respective planetary gearset (P1, P2, P3), the second element (E21, E22, E23) in the case of a minus planetary gearset by each a planet carrier and, in the case of a plus planetary gear set, by a ring gear of the respective planetary gear set (P1, P2, P3), the third element (E31, E32, E33) being formed by the respective ring gear and in the case of a minus planetary gear set a plus planetary set through the respective planetary web of the respective planetary gear set zes (P1, P2, P3) is formed, wherein a first (A), a second (B), a third (C), a fourth (D), a fifth (E) and a sixth switching element (F) are provided , through the selective actuation of which six gears between the input shaft (GW1) and the output shaft (GWA) can be represented, and wherein a rotor (R) of the electric machine (EM) on the input shaft (GW1), the output shaft (GWA) or at least one of the Elements (E11, E12, E13, E21, E22, E23, E31, E32, E33) of the planetary gear sets (P1, P2, P3) are connected, characterized in that the third element (E32) of the second planetary gear set (P2) and the second element (E23) of the third planetary gear set (P3) are connected to one another in a rotationally fixed manner, - that the output shaft (GWA) is rotationally fixed to the second element (E21) of the first planetary gear set (P1) and the second element (E22) of the second planetary gear set (P2). connects with each other, - that the third element (E31) of the first planetary gear set (P1) and the first element (E12) of second planetary gearset (P2) are connected to one another in a torque-proof manner and can be fixed together via the first shifting element (A),- that the first element (E11) of the first planetary gearset (P1) can be fixed by means of the second shifting element (B),- and that the The input shaft (GW1) can be connected in a rotationally fixed manner to the output shaft (GWA) via the third shifting element (C) and can be connected in a rotationally fixed manner to the first element (E11) of the first planetary gear set (P1) by means of the sixth shifting element (F).

Description

The invention relates to a transmission for a motor vehicle, comprising an electric machine, an input shaft, an output shaft, and a first planetary gear set, a second planetary gear set and a third planetary gear set, with the first, the second and the third planetary gear set each having a first element and a second element each Element and each have a third element, the first element being formed by a respective sun gear of the respective planetary gear set, the second element being formed by a planet carrier in the case of a minus planetary gear set and by a ring gear of the respective planetary gear set in the case of a plus planetary gear set is formed, with the third element being formed by the respective ring gear in the case of a minus planetary gearset and by the respective planet carrier of the respective planetary gearset in the case of a plus planetary gearset, with a first, a second, a third, a fourth, a fifth and a sixth switching element are provided by the en selective actuation six gears between the input shaft and the output shaft can be represented, and wherein a rotor of the electric machine is connected to the input shaft, the output shaft or at least one of the elements of the planetary gear sets.

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 2014 218 610 A1 shows a transmission which, in addition to an input shaft and an output shaft, includes three planetary gear sets and an electric motor. Furthermore, in one variant, six shifting elements are provided, via which different power flows from the 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.

More gears are from the DE 10 2015 223 291 A1 , the DE 10 2016 211 878 A1 and the DE 10 2017 223 157 A1 famous.

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 12. Furthermore, claims 13 and 14 each relate to a method for operating a transmission.

According to the invention, a transmission includes an electric machine, an input shaft, an output shaft and a first planetary gear set, a second planetary gear set and a third planetary gear set. The planetary gear sets comprise a plurality of elements, with each of the planetary gear sets being assigned a first element, a second element and a third element. The first element is formed by a respective sun gear of the respective planetary gearset, while the second element is formed by a respective planet carrier in the case of a minus planetary gearset and by a respective ring gear of the respective planetary gearset in the case of a plus planetary gearset. In the case of a minus planetary gear set, the third element is present as a ring gear and in the case of a plus planetary gear set as a planet carrier of the respective planetary gear set.

The planetary gear sets can, insofar as it allows the elements to be connected, each be present as a minus planetary gear set within the scope of the invention, with the first element of the respective planetary gear set being a sun gear, the second element of the respective planetary gear set being a planet carrier and the third element of the respective planetary gear set is a ring gear. A negative planetary gear set is composed of the elements sun gear, planetary carrier and ring gear in a manner known in principle to those skilled in the art, with the planetary carrier being rotatably mounted at least one, but preferably several planetary gears in detail mesh with both the sun gear and the surrounding ring gear.

Alternatively, one or more of the planetary gear sets could be present as a plus planetary gear set, provided the connection of the respective elements allows it, with the first element of the respective planetary gear set being a sun gear and the second element of the respective planetary gear set being a sun gear Ring gear and the third element of each planetary gear set is a planet carrier. A plus planetary gear set also has the elements sun gear, ring gear and planetary carrier, with the latter guiding at least one pair of planetary gears, in which one planetary gear meshes with the internal sun gear and the other planetary gear meshes with the surrounding ring gear, and the planetary gears mesh with one another.

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. However, all three planetary gear sets are particularly preferably present as minus planetary gear sets.

In addition, a first, a second, a third, a fourth, a fifth and a sixth shifting element are provided, through the selective actuation of which six gears can be produced between the input shaft and the output shaft. Particularly preferably, exactly six different gears can be formed between the input shaft and the output shaft in terms of the transmission ratio. Furthermore, the electric machine is connected to the input shaft, to the output shaft or to at least one of the elements of the planetary gear sets.

A “shaft” in the context of the invention is understood to mean a rotatable component of the transmission, via which associated components of the transmission are connected to one another in a torque-proof manner or via which such a connection is established when a corresponding shifting element is actuated. The respective shaft can connect the 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 the context of the invention, “axial” means an orientation in the direction of a longitudinal central axis, along which the planetary gear sets are arranged lying coaxially to one another. “Radial” is then to be understood as meaning an orientation in the diameter direction of a shaft that lies on this longitudinal central axis.

The output shaft of the transmission preferably has teeth, 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. The toothing is preferably provided at a connection point of the output shaft, this connection point of the output shaft being located in particular axially in the area of one end of the transmission, at which there is also a connection point of the 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.

As an alternative to this, an output of the transmission could in principle also be provided at an axial end of the transmission which is opposite to a connection point of the drive shaft. In this case, a connection point of the output shaft is then configured on an axial end of the output shaft coaxially with a connection point of the drive shaft, so that the input and output of the transmission are placed on 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. In both of the aforementioned cases, the input shaft and the output shaft are preferably coaxial with one another.

Within the scope of the invention, the planetary gear sets are preferably arranged axially following the connection point of the drive shaft in the order of first planetary gear set, second planetary gear set and third planetary gear set. The planetary gear sets are preferably provided coaxially to the input shaft and the output shaft.

The invention now includes the technical teaching that the third element of the second planetary gear set and the second element of the third planetary gear set are non-rotatably connected to one another. The output shaft non-rotatably connects the second element of the first planetary gear set and the second element of the second planetary gear set, while the third element of the first planetary gear set netenradsatzes and the first element of the second planetary gear set are rotatably connected to each other and can be fixed together on the first switching element. Furthermore, the first element of the first planetary gearset can be fixed by means of the second shifting element, whereas the input shaft can be connected in a torque-proof manner to the output shaft via the third shifting element and can be connected in a torque-proof manner to the first element of the first planetary gearset by means of the sixth shifting element.

In other words, in the transmission according to the invention, the output shaft is constantly non-rotatably connected to the second element of the first planetary gear set and also to the second element of the second planetary gear set, while the third element of the second planetary gear set and the second element of the third planetary gear set are permanently non-rotatably connected to one another . Likewise, the third element of the first planetary gear set and the first element of the second planetary gear set are constantly connected to one another in a torque-proof manner.

Closing the first shifting element locks the third element of the first planetary gear set and the first element of the second planetary gear set together and consequently prevents them from rotating, while actuating the second shifting element locks the first element of the first planetary gear set. In the actuated state, the third switching element connects the input shaft and the output shaft to one another in a rotationally fixed manner, whereas closing the sixth switching element results in a rotationally fixed connection of the first element of the first planetary gear set to the input shaft.

The third and the sixth switching element are present as clutches which, when actuated, in each case adjust the rotational movements of the components of the transmission directly connected thereto, if necessary, and then connect them to one another in a rotationally fixed manner. On the other hand, the first switching element and also the second switching element are each designed as a brake, which fixes the component or components directly connected thereto when actuated and subsequently prevents a rotational movement.

The first switching element is preferably provided essentially in one plane with the first planetary gear set, in that it is arranged axially largely at the height of the first planetary gear set and radially surrounding it. The second shifting element is in particular placed axially on a side of the first planetary gearset facing away from the second planetary gearset, while the third shifting element and the sixth shifting element are preferably provided axially between the first planetary gearset and the second planetary gearset. In this case, the sixth shifting element is more preferably located axially between the first planetary gear set and the third shifting element.

A respective non-rotatable connection of the rotatable components of the transmission is preferably realized according to the invention via one or more intermediate shafts, which can also be present as short intermediate pieces when 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 only connected to one another by actuation of a respective shifting element, a connection is also preferably implemented via one or more intermediate shafts.

Fixing takes place in particular by non-rotatable connection with a non-rotatable component of the transmission, which is preferably a permanently stationary component, preferably a housing of the transmission, a part of such a housing or a non-rotatably connected component.

The "connection" of the rotor of the electric machine to the drive shaft, the output shaft or at least one of the elements of the planetary gear sets 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 rotatable component(s) of the transmission prevails.

Overall, a transmission according to the invention is characterized by a compact design, low component loads, good gearing efficiency and low losses.

According to one embodiment of the invention, the first member of the third planetary gear set is non-rotatably connected to the third member of the first planetary gear set and the first member of the second planetary gear set. In addition, the drive shaft can rotate via the fourth switching element with the third element of the second planetary gear set and the second element of the third Planetary gear set connected and rotatably connected by means of the fifth switching element with the third element of the third planetary gear set.

In this embodiment, the third element of the first planetary gear set, the first element of the second planetary gear set and the first element of the third planetary gear set are constantly connected to one another in a rotationally fixed manner, so that a closing of the first shifting element accordingly also causes the first element of the third planetary gear set to become stuck . When the fourth shifting element is actuated, the third element of the second planetary gear set and the second element of the third planetary gear set are non-rotatably connected to the drive shaft, while closing the fifth shift element results in a non-rotatable connection of the drive shaft to the third element of the third planetary gear set.

The fourth shifting element and the fifth shifting element are present as clutches, with the fourth shifting element and the fifth shifting element preferably being arranged axially on a side of the third planetary gearset that faces away from the second planetary gearset, with the fourth shifting element more preferably being arranged axially between the third planetary gearset and the fifth switching element.

According to an alternative possible embodiment of the invention, the third element of the third planetary gear set is non-rotatably connected to the drive shaft, while the fourth shifting element when actuated is non-rotatably connected to the first element and the second element of the third planetary gear set or the second element and the third element of the third planetary gear set . Furthermore, the first element of the third planetary gear set can be brought into connection with the third element of the first planetary gear set and the first element of the second planetary gear set via the fifth switching element in a torque-proof manner.

In this configuration option, the drive shaft and the third element of the third planetary gear set are permanently connected to one another in a rotationally fixed manner, whereas closing the fourth shifting element results in the third planetary gear set being locked, in that either the first element and the second element of the third planetary gear set or the second element and the third member of the third planetary gear set are non-rotatably connected to each other. On the other hand, when actuated, the fifth shifting element connects the first element of the third planetary gear set in a torque-proof manner with the third element of the first planetary gear set and the first element of the second planetary gear set.

In this case, too, the fourth shifting element and the fifth shifting element are present as clutches, with the fifth shifting element preferably being provided axially between the second planetary gearset and the third planetary gearset. Depending on the connection to be made, the fourth shifting element is either arranged axially on a side of the third planetary gearset facing away from the second planetary gearset or also axially between the second and third planetary gearsets.

In a further development of the invention, the rotor of the electric machine is non-rotatably connected to the third element of the second planetary gear set and the second element of the third planetary gear set, whereby it is also conceivable as an alternative to this that the rotor of the electric machine is connected to the third element of the second planetary gear set and the second element of the third planetary gear set is connected via at least one transmission stage.

The electric machine can either be arranged coaxially to the planetary gear sets or offset from the axis of these. In the first case, the rotor of the electric machine can either be directly non-rotatably connected to the third element of the second planetary gear set and the second element of the third planetary gear set, or it can be coupled to them via one or more intermediate gear ratio stages, with the latter being 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. With a coaxial arrangement of the electric machine, the planetary gear sets can then more preferably be arranged at least partially axially in the area of the electric machine and lying radially on the inside of it, so that the axial overall 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 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. Even with the off-axis arrangement of the electric machine, the planetary gear sets can be placed at least in part axially at the height of the electric machine.

According to one embodiment of the invention, in particular in combination with the arrangement of the electric machine described above, six gears between the first input shaft and the output shaft result from selectively closing the six shifting elements. Thus, a first gear between the input shaft and the output shaft can be achieved by actuating the first and sixth shifting element, while a second gear between the input shaft and the output shaft results by closing the first and fifth shifting element. A third gear is shifted between the drive shaft and the output shaft by actuating the first shifting element and the fourth shifting element, whereas a fourth gear results between the drive shaft and the driven shaft in a first variant by engaging the first shifting element and the third shifting element.

In addition, the fourth gear can be activated in a second variant by actuating the second and the third shifting element, in a third variant by engaging the third and the fourth shifting element, in a fourth variant by actuating the third and the fifth shifting element, in a fifth variant by closing the third and sixth switching element, in a sixth variant by actuating the fourth and fifth switching element, in a seventh variant by closing the fourth and sixth switching element, in an eighth variant by actuating the fifth and sixth switching element and in one ninth variant are switched by closing the third switching element.

In the ninth variant, there is already fourth gear, since the input shaft and the output shaft are then non-rotatably connected to one another. An electric machine connected to the third element of the second planetary gear set and the second element of the third planetary gear set is then advantageously decoupled, so that pure driving can be realized via the upstream drive machine and thus no-load losses of the electric machine can be avoided. However, the electric motor is integrated in the first eight variants of the fourth gear, so that hybrid functions can be implemented.

A fifth gear can be shifted between the input shaft and the output shaft by closing the second switching element and the fourth switching element, whereas a sixth gear results between the input shaft and the output shaft by actuating the second switching element and the fifth switching element.

With a suitable choice of fixed gear ratios of the planetary gear sets, a range of ratios suitable for use in the area of a motor vehicle is thereby 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 dem Rotor der Elektromaschine und der Abtriebswelle für ein rein elektrisches Fahren genutzt werden, wobei sich dieser erste Gang durch Schließen des ersten Schaltelements ergibt. Dadurch ist der Rotor der Elektromaschine über den zweiten Planetenradsatz mit der Abtriebswelle gekoppelt, wobei eine Übersetzung dieses ersten Ganges dabei einer Übersetzung des dritten, zwischen der Antriebswelle und der Abtriebswelle wirksamen Ganges entspricht.

When the electric machine is connected to the third element of the second planetary gear set and the second element of the third planetary gear set, different operating modes can also be implemented in a simple manner:

• Thus, a first gear between the rotor of the electric machine and the output shaft can be used for purely electric driving, with this first gear resulting from the closing of the first shifting element. As a result, the rotor of the electric machine is coupled to the output shaft via the second planetary gear set, with a transmission ratio of this first gear corresponding to a transmission ratio of the third gear effective between the input shaft and the output shaft.

In addition, a second gear can be implemented between the rotor of the electric machine and the output shaft for purely electric driving. To shift this second gear, the second shifting element must be actuated so that the rotor of the electric machine is then connected to the output shaft via the first and the second planetary gear set. A translation of this second gear effective between the rotor of the electric machine and the output shaft corresponds to the translation of the fifth gear effective between the input shaft and the output shaft.

Starting from purely electric driving in the first gear, which is active between the rotor of the electric machine and the output shaft, the upstream drive machine can then be shifted to the first gear, which is active between the input shaft and the output shaft, or to the second gear, which is active between the input shaft and the output shaft, or in the third gear effective between the input shaft and the output shaft or in the first variant of the fourth gear effective between the input shaft and the output shaft, since the first shifting element is also involved in each of these gears.

Likewise, from the second gear effective between the rotor of the electric machine and the output shaft, it is also possible to start the upstream drive machine into the second variant of the fourth gear effective between the input shaft and the output shaft, into the fifth gear effective between the input shaft and the output shaft as well as in the sixth gear effective between the input shaft and the output shaft, since the second switching element is also closed in these gears.

As a further operating mode, charging of an electrical energy store can also be implemented by merely closing the fourth shifting element and thus producing a non-rotatable connection of the drive shaft with the third element of the second planetary gear set and the second element of the third planetary gear set and thus also with the electric machine. The rotor of the electric machine runs at the same speed as the drive shaft when it is connected to the third element of the second planetary gear set and the second element of the third planetary gear set in a rotationally fixed connection. 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.

As a further operating mode, a starting mode for reversing when driven via the drive shaft and thus the upstream drive machine can also be implemented. For this purpose, the sixth switching element is closed, so that the drive motor drives via the first element of the first planetary gear set and at the same time supports the electric machine on the third element of the second planetary gear set, while an output is generated via the second element of the first planetary gear set and the second element of the second planetary gear set takes place. The non-rotatable connection between the third element of the first planetary gear set and the first element of the second planetary gear set causes the first and second planetary gear sets to be coupled. By supporting the torque via the electric machine, starting for reverse travel can be implemented. From this starting mode, the upstream drive machine can reach the first gear or the fifth variant or the seventh variant or the eighth variant of the fourth gear.

Furthermore, power shifts with traction support can be implemented: when changing gears between the first gear, which is effective between the input shaft and the output shaft, and the second gear, which is effective between the input shaft and output shaft, the traction can be supported by the electric machine when the first shifting element is closed, with the Synchronization of the switching element to be closed takes place via a speed control of the upstream drive machine. Alternatively, this can also be done by synchronized shifting elements or by another, separate synchronization device, such as a transmission brake or another electric machine that can be operatively connected directly or indirectly to the drive shaft. If a further switching element is also provided on the drive side of the drive shaft as a separating clutch, the inertial mass of the upstream drive machine can be decoupled during synchronization. Likewise, shifting between the second gear effective between the input shaft and the output shaft and the third gear effective between the input shaft and the output shaft and between the third gear effective between the input shaft and the output shaft and the first variant of the fourth gear, between the input shaft and the output shaft effective gear can be realized when the first switching element is closed.

Before a further upshift into the fifth gear effective between the input shaft and the output shaft, it is then first necessary to switch between the first variant and the second variant of the fourth gear. After this, a gear change under load can then take place between the second variant of the fourth gear effective between the input shaft and the output shaft and the fifth gear effective between the input shaft and the output shaft with the second shifting element closed, with the tractive force being exerted by the electric machine supported and a synchronization of the switching element to be closed is realized by speed control of the upstream drive machine. The same can also be shown for a gear change between the fifth gear effective between the input shaft and the output shaft and the sixth gear effective between the input shaft and the output shaft.

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 fourth gear, in that the first shifting element initially remains closed either after a torque-assisted shift from third to fourth gear via the electric machine or after starting the engine in fourth gear. Now, however, a speed of the electric machine in four th gear at higher driving speeds can be switched from the first variant of the fourth gear to the second variant of the fourth gear, since here the rotor of the electric machine has a lower speed than in the first variant of the fourth gear. This switchover takes place while maintaining the tractive force via the upstream drive machine when the third switching element is closed. First of all, the load-free, first shifting element is disengaged and then the load-free, second shifting element is engaged, with the speed being adjusted by speed control of the electric machine.

No separate shifting element is required for decoupling the upstream drive machine, since the upstream drive machine can be decoupled in the second variant of the fourth gear effective between the input shaft and the output shaft by opening the third shifting element. As a result, the second gear is then realized, which is effective between the rotor of the electric machine and the output shaft. In addition, the second variant of fourth gear is required in order to be able to shift into fifth gear under load. In addition, when the vehicle is slowing down, a downshift from the fourth gear, which is effective between the input shaft and the output shaft, to the third gear, which is effective between the input shaft and the output shaft, can be prepared by first changing from the second variant to the first variant of the fourth gear and while the traction is obtained when the third switching element is closed via the upstream drive machine. In the first variant of the fourth gear, the first shifting element is then in turn closed, which is required in order to support the tractive force via the electric machine in the course of the downshift from fourth to third gear.

In a further development of the invention, one or more 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, all shifting elements are implemented as positive-locking shifting elements, so that the lowest possible drag losses can be achieved.

However, it is also a conceivable variant of the invention for the first shifting element to be designed as a non-positive shifting element, which can specifically be present as a multi-plate shifting element. This has the advantage that from a charging operation with the fourth switching element closed, the motor vehicle can be started or crawled by slipping closure of the first switching element, with the first switching element acting as an integrated starting element. In this respect, a delay-free start from the loading mode can be represented.

As an alternative or in addition to this, the second shifting element can be designed as a non-positive shifting element and here in particular as a multi-plate shifting element. As a result, traction upshifts and traction downshifts between the first gear effective between the rotor of the electric machine and the output shaft and the second gear effective between the rotor of the electric machine and the output shaft can be implemented under load. If the first shifting element is also designed as a non-positive shifting element, the two gears between the rotor of the electric machine and the output shaft can be shifted under full power, i.e. pull-up, pull-down, overrun-up and overrun downshifts are possible.

If a frictional separating clutch is also provided between the upstream drive machine and the transmission, a drag start of the upstream drive machine can be represented from the two gears effective between the rotor of the electric machine and the output shaft.

According to a further embodiment of the invention, the third switching element and the sixth switching element are combined to form a pair of switching elements, to which an actuating element is assigned. In this case, on the one hand the third switching element and on the other hand the sixth switching element can be actuated via the actuating element from a neutral position. This has the advantage that the number of actuating elements can be reduced by combining them, and thus the production costs can also be reduced. In this case, however, the fifth variant of the fourth gear effective between the input shaft and the output shaft cannot be implemented, since the third shifting element and the sixth shifting element must be actuated simultaneously for this purpose.

As an alternative or in addition to the aforementioned variant, the fourth switching element and the fifth switching element are combined to form a pair of switching elements, to which an actuating element is assigned. This actuating element can be used to actuate the fourth shifting element on the one hand and the fifth shifting element on the other hand from a neutral position. Through this the production costs can be reduced by combining the two switching elements into a pair of switching elements, in that an actuating device can be used for both switching elements. However, in this case the sixth variant of the fourth gear effective between the input shaft and the output shaft cannot be represented, since this requires simultaneous actuation of the fourth shifting element and the fifth shifting element.

As a further alternative or in addition to the two aforementioned variants, it is also conceivable within the scope of the invention to combine the first switching element and the second switching element to form a pair of switching elements. In this case, a common actuating element would then actuate the first switching element on the one hand and the second switching element on the other from a neutral position.

Particularly preferably, at least two aforementioned pairs of shifting elements are implemented, so that the four shifting elements of the transmission can be actuated via two 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 drive shaft of the transmission. In this case, one of the shifting elements of the transmission or the separating clutch that may be present 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. In this case, the 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 separating clutch or a 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.

For the purposes of the invention, the fact that two components of the transmission are “connected” or “coupled” or “are connected to one another” means a permanent coupling of these components so that they cannot rotate independently of one another. 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. The reference of the claims to the drawings through the use of reference numbers shall not limit the scope of the claims.

• 1 eine schematische Ansicht eines Kraftfahrzeugantriebsstranges;
• 2 bis 8 jeweils eine schematische Ansicht je eines Getriebes, wie es jeweils bei dem Kraftfahrzeugantriebsstrang aus 1 zur Anwendung kommen kann;
• 9 ein beispielhaftes Schaltschema der Getriebe aus den 2 bis 8; und
• 10 bis 15 jeweils eine schematische Darstellung je einer Abwandlungsmöglichkeit der Getriebe aus den 2 bis 8.

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;
• 2 until 8th each a schematic view of a transmission, as in each case in the motor vehicle drive train 1 may apply;
• 9 an exemplary shift pattern of the transmission from the 2 until 8th ; and
• 10 until 15 each a schematic representation of a possible modification of the transmission from the 2 until 8th .

1 shows a schematic view of a motor vehicle drive train of a hybrid vehicle, with an internal combustion engine ICE being connected to a transmission G via an intermediate torsional vibration damper TS in the motor vehicle drive train. A differential gear AG is connected downstream of the gear G on the output side, via which a drive power is distributed to drive wheels DW of a drive axle of the motor vehicle. The gear G and the torsional vibration damper TS are arranged in a common housing of the gear G, in which the differential gear AG can then also be integrated. As also in 1 As can be seen, the internal combustion engine VKM, the torsional vibration damper TS, the gear G and also the differential gear AG are aligned transversely to a direction of travel of the motor vehicle.

the end 2 shows a schematic representation of the transmission G according to a first embodiment of the invention. As can be seen, the transmission G is composed of a wheel set RS and an electric machine EM, which are arranged together in the housing of the transmission G. The gear set RS comprises three planetary gear sets P1, P2 and P3, each of the planetary gear sets P1, P2 and P3 having a first element E11 or E12 or E13, a second element E21 or E22 or E23 and a third element E31 or E32 or E33. The respective first element E11 or E12 or E13 is formed by a respective sun gear of the respective planetary gear set P1 or P2 or P3, while the respective second element E21 or E22 or E23 of the respective planetary gear set P1 or P2 or P3 as a planet carrier and the respective third element E31 or E32 or E33 of the respective planetary gear set P1 or P2 or P3 as a ring gear.

In the present case, the first planetary gear set P1, the second planetary gear set P2 and also the third planetary gear set P3 are each present as a negative planetary gear set, whose respective planet carrier guides at least one planet gear in a rotatably mounted manner, which is connected to both the respective radially inner sun gear and the respective radially surrounding ring gear is in tooth engagement. However, a plurality of planet gears are particularly preferably provided in the first planetary gear set P1, in the second planetary gear set P2 and also in the third planetary gear set P3.

If the connection allows it, the first planetary gear set P1, the second planetary gear set P2 and the third planetary gear set P3 could each also be designed as a plus planetary gear set, with the respective second element E21 or E22 or E23 is formed by the respective ring gear and the respective third element E31 or E32 or E33 by the respective planet carrier and, in addition, a respective transmission ratio has to be increased by one. In a plus planetary gearset, the planetary carrier then guides at least one pair of planetary gears in a rotatably mounted manner, of whose planetary gears a planetary gear meshes with the radially inner sun gear and a planetary gear meshes with the radially surrounding ring gear, and the planetary gears mesh with one another.

As in 2 can be seen, the transmission G comprises a total of six shifting elements in the form of a first shifting element A, a second shifting element B, a third shifting element C, a fourth shifting element D, a fifth shifting element E and a sixth shifting element F. The shifting elements A, B , C, D, E and F are each designed as form-fit shifting elements and are preferably present as claw shifting elements. In addition, the third shifting element C, the fourth shifting element D, the fifth shifting element E and the sixth shifting element F are each designed as clutches, while the first shifting element A and the second shifting element B are present as brakes.

The third element E31 of the first planetary gear set P1, the first element E12 of the second planetary gear set P2 and the first element E13 of the third planetary gear set P3 are connected to one another in a rotationally fixed manner and can be fixed together by closing the first shifting element A on a rotationally fixed component GG, in which it this is in particular the gearbox housing of the gearbox G or a part of the gearbox housing. Likewise, the first ele ment E11 of the first planetary gear set P1 fixed via the second switching element B on the non-rotatable component GG and consequently prevented from rotating. An output shaft GWA of the transmission G connects the second element E21 of the first planetary gear set P1 and the second element E22 of the second planetary gear set P2 to one another in a torque-proof manner, with the output shaft GWA also being connected in a torque-proof manner to an input shaft GW1 of the transmission G by closing the third shifting element C can.

As also in 2 As can be seen, the third element E32 of the second planetary gear set P2 and the second element E23 of the third planetary gear set P3 are constantly connected to one another in a rotationally fixed manner and are also jointly rotationally fixed to a rotor R of the electric machine EM, the stator S of which is permanently fixed to the rotationally fixed component GG is. By closing the fourth shifting element D, the third element E32 of the second planetary gear set P2 and the second element E23 of the third planetary gear set P3 and thus also the rotor R of the electric machine EM can be non-rotatably connected to the drive shaft GW1. The drive shaft GW1 can also be non-rotatably connected to the third element E33 of the third planetary gearset P3 via the fifth shifting element E and can be non-rotatably connected to the first element E11 of the first planetary gearset P1 by closing the sixth shifting element F.

Both the drive shaft GW1 and the output shaft GWA each form a connection point GW1-A or GWA-A, with the connection point GW1-A being formed in the motor vehicle drive train 1 a connection to the internal combustion engine VKM is used, while the transmission G is connected to the connection point GWA-A with the subsequent differential transmission AG. The connection point GW1-A of the drive shaft GW1 is designed at an axial end of the transmission G, with the connection point GWA-A of the output shaft GWA lying at the same axial end and being aligned transversely to the connection point GW1-A of the drive shaft GW1. In addition, the input shaft GW1 and the output shaft GWA are arranged lying coaxially to one another.

The planetary gear sets P1, P2 and P3 are also coaxial with the input shaft GW1 and the output shaft GWA, where they are arranged axially following the connection point GW1 -A of the input shaft GW1 in the order of first planetary gear set P1, second planetary gear set P2 and finally third planetary gear set P3. Likewise, the electric machine EM is placed coaxially to the planetary gear sets P1, P2 and P3 and thus also to the input shaft GW1 and the output shaft GWA, with the electric machine EM being provided axially between the second planetary gear set P2 and the third planetary gear set P3.

As also in 2 As can be seen, the first shifting element A is arranged essentially in one plane with the first planetary gear set P1 by being provided axially largely at the height of the first planetary gear set P1 and radially surrounding it. The second shift element B is placed axially on a side of the first planetary gear set P1 opposite the second planetary gear set P2, while the third shift element C and the sixth shift element F are located axially between the first planetary gear set P1 and the second planetary gear set P2. The sixth shifting element F is arranged axially between the first planetary gear set P1 and the third shifting element C. Finally, the fourth shifting element D and the fifth shifting element E are provided axially on a side of the third planetary gearset facing away from the second planetary gearset P2, with the fourth shifting element D being placed axially between the third planetary gearset P3 and the fifth shifting element E.

The third shifting element C and the sixth shifting element F are placed axially directly next to each other and radially at the same height and have a common actuating element, via which the third shifting element C on the one hand and the sixth shifting element F on the other hand can be actuated from a neutral position. In this respect, the third shifting element C and the sixth shifting element F are combined to form a shifting element pair SP1.

Likewise, the fourth shifting element D and the fifth shifting element E are arranged axially directly next to one another and radially at essentially the same height and combined to form a shifting element pair SP2, in which the fourth shifting element D and the fifth shifting element E are assigned a common actuating element, via which a neutral position out on the one hand the fourth switching element D and on the other the fifth switching element E can be actuated.

3 shows a schematic representation of a transmission G according to a second possible embodiment of the invention. This configuration option can be used in the motor vehicle drive train in 1 are used and largely corresponds to the variant 2 . What is different, however, is that the first shifting element A is now designed as a non-positive shifting element, with the first shifting element A preferably being present as a multi-plate shifting element. Incidentally, the configuration option 3 according to the variant 2 , so that reference is made to what has been described here.

Furthermore goes out 4 a schematic view of a transmission G according to a third embodiment of the invention, as is also the case with the motor vehicle drive train in 1 can find application. This embodiment essentially corresponds to the variant 2 , with the difference that now the second switching element B is designed as a non-positive switching element and is specifically present as a multi-plate switching element. The second switching element B is provided axially between the connection point GW1-A of the drive shaft GW1 and the connection point GWA-A of the output shaft GWA. 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 G according to a fourth possible embodiment of the invention. This can also be used in the motor vehicle drive train in 1 come into use, with the configuration option largely according to the variant 2 is equivalent to. In contrast to this, both the first shifting element A and the second shifting element B are now implemented as non-positive shifting elements, with the shifting elements A and B in each case being present as multi-plate shifting elements. Again, the second switching element B is provided axially between the connection point GW1-A of the drive shaft GW1 and the connection point GWA-A of the output shaft GWA. For the rest, the configuration option corresponds to 5 otherwise according to the variant 2 , so that reference is made to what has been described here.

the end 6 shows a schematic view of a transmission G according to a fifth embodiment of the invention, as is also used in the motor vehicle drive train in 1 can find application. This embodiment essentially corresponds to the variant 2 In contrast to this, the third switching element C and the sixth switching element F are no longer combined to form a pair of switching elements. In this respect, the third switching element C and the sixth switching element F can be actuated independently of one another. Otherwise, the embodiment corresponds to 6 according to the variant 2 , so that reference is made to what has been described here.

7 shows a schematic representation of a transmission G according to a sixth possible embodiment of the invention, which is also essentially the embodiment 2 is equivalent to. This design option can also be used in the motor vehicle drive train in 1 come into use and differs from the embodiment 2 in that the third element E33 of the third planetary gear set P3 is now permanently non-rotatably connected to the drive shaft GW1, while the first element E13 of the third planetary gear set P3 is not constantly non-rotatably connected to the third element E31 of the first planetary gear set P1 and the first element E12 of the second planetary gear set P2 is connected, but only by closing a fifth switching element E is rotatably connected to this. The fifth shifting element E is provided axially between the second planetary gear set P2 and the third planetary gear set P3. Finally, by closing a fourth shifting element D, the second element E23 of the third planetary gear set P3 and the third element E33 of the third planetary gear set P3 are non-rotatably connected to one another, which results in the third planetary gear set P3 being blocked. Otherwise, the embodiment corresponds to 7 according to the variant 2 , so that reference is made to what has been described here.

Furthermore goes out 8th a schematic view of a transmission G according to a seventh embodiment of the invention, which is also used in the motor vehicle drive train in 1 Can find application and largely according to the previous variant 7 is equivalent to. What is different now is that the third planetary gearset P3 can be blocked by a fourth shifting element D connecting the first element E13 and the second element E23 of the third planetary gearset P3 in a torque-proof manner when actuated. The fourth shifting element D is also provided axially between the second planetary gearset P2 and the third planetary gearset P3, being specifically between the second planetary gearset P2 and the fifth shifting element E. In addition, the fourth shifting element D and the fifth shifting element E are combined to form a shifting element pair SP2. Otherwise, the embodiment corresponds to 8th according to the variant 7 , so that reference is made to what has been described here.

In 9 is an exemplary shift pattern for the transmission G from the 2 until 8th tabulated. As can be seen, a total of six gears 1 to 6 can be implemented here between the input shaft GW1 and the output shaft GWA, with an X in the columns of the shift pattern identifying which of the shifting elements A to F is in which of the gears 1 to 6 each is closed.

As in 9 can be seen, a first gear 1 between the drive shaft GW1 and the Output shaft GWA switched by pressing the first switching element A and the sixth switching element F. Furthermore, there is a second gear 2 between the input shaft GW1 and the output shaft GWA by engaging the first shifting element A and the fifth shifting element E, while a third gear 3 between the input shaft GW1 and the output shaft GWA by actuating the first shifting element A and of the fourth switching element D is shown.

A fourth gear between the input shaft GW1 and the output shaft GWA is shifted in a first variant 4.1 by actuating the first shifting element A and the third shifting element C, with the fourth gear also shifting in a second variant 4.2 by actuating the second shifting element B and the third switching element C, in a third variant 4.3 by closing the third switching element C and the fourth switching element D, in a fourth variant 4.4 by actuating the third switching element C and the fifth switching element E, in a fifth variant 4.5 by closing the third switching element C and of the sixth switching element F, in a sixth variant 4.6 by actuating the fourth switching element D and the fifth switching element E, in a seventh variant 4.7 by closing the fourth switching element D and the sixth switching element F, in an eighth variant 4.8 by actuating the fifth switching element E and the sixth switching element F and in a ninth variant 4.9 by closing the third switching element C results.

While the electric machine EM is integrated in the first eight variants 4.1 to 4.8, so that it is possible to drive in a hybrid manner while using the internal combustion engine ICE at the same time, the electric machine EM is decoupled in the case of the last variant 4.9. As a result, no-load losses of the electric machine EM can be avoided, while the drive shaft GW1 is directly connected to the output shaft GWA in a rotationally fixed manner via the third switching element C. The fifth variant 4.5 can also only be used in the variant after 6 be realized, in which a simultaneous actuation of the third switching element C and the sixth switching element F is possible. In addition, the sixth variant 4.6 can only be used with the transmission G 7 be switched, since only her simultaneous actuation of the fourth switching element D and the fifth switching element E can take place.

In addition, a fifth gear 5 between the input shaft GW1 and the output shaft GWA is achieved by engaging the second shifting element B and the fourth shifting element D, whereas a sixth gear 6 results from actuating the second shifting element B and the fifth shifting element E.

Although the shifting elements A to F are each designed as positive shifting elements, shifting between the first gear 1 and the second gear 2 can be implemented under load, since the first shifting element A is involved in both. Likewise, a gear change between the second gear 2 and the third gear 3 and between the third gear 3 and the first variant 4.1 of the fourth gear can also take place under load, since the first shifting element A is closed here as well. In fourth gear, before a further upshift to fifth gear 5, you have to switch between variants 4.1 and 4.2, with the internal combustion engine ICE maintaining the tractive force via the closed third switching element C and switching between the first switching element A and the second switching element B will.

After a change to variant 4.2 of the fourth gear can then be changed under load between the second variant 4.2 of the fourth gear and the fifth gear 5, and also between the fifth gear 5 and the sixth gear 6 under load, since at these in each case the second switching element B is involved. 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.

The gears G from the 2 until 8th can also be operated in other operating modes with the help of the electric machine EM: purely electric driving can take place in a first gear E1, which is effective between the rotor R of the electric machine EM and the output shaft GWA and for which the first shifting element A in is to be transferred to a closed state. As a result, the rotor R is coupled to the output shaft GWA via the second planetary gear set P2, with the transmission ratio of the first gear E1 corresponding to the transmission ratio of the third gear 3 effective between the input shaft GW1 and the output shaft GWA.

Advantageously, starting from first gear E1, the internal combustion engine ICE can be started in first gear 1, in second gear 2, in third gear 3 and also in first variant 4.1 of fourth gear, since in each of these Gears in each case the first switching element A is closed. In this respect, it is possible to quickly switch from purely electric driving to driving using the internal combustion engine or hybrid driving.

In addition, a second gear E2 can be shown between the rotor R of the electric machine EM and the output shaft GWA, for which the second shifting element B is to be closed. As a result, the output shaft GWA is coupled to the rotor R of the electric machine EM via the first planetary gear set P1 and the second planetary gear set P2. A translation of this gear E2 corresponds to the translation of the fifth gear 5 between the input shaft GW1 and the output shaft GWA.

Starting from the second gear E2, the internal combustion engine ICE can be started in the second variant 4.2 of the fourth gear, in the fifth gear 5 and in the sixth gear 6, since the second shifting element B is involved in each of these. As a result, it is also possible here to switch quickly from purely electric driving to driving using the internal combustion engine or hybrid driving.

Furthermore, by closing the fourth switching element D, a charging or starting function can be implemented. In the closed state of the fourth shifting element D, the third element E32 of the second planetary gear set P2 and the second element E23 of the third planetary gear set P3 and thus also the rotor R of the electric machine EM are directly rotationally fixed or via the blocked, third planetary gear set P3 to the drive shaft GW1 connected and thus also with the internal combustion engine VKM. At the same time, however, there is no frictional connection to the output shaft GWA, with the rotor R rotating at the same speed as the input shaft GW1. In the generator operation of the electric machine EM, an electrical energy store can be charged via the internal combustion engine VKM, while in the electric motor operation of the electric machine EM, the internal combustion engine VKM can be started via the electric machine EM.

A start-up function for reversing EDA-R can also be implemented as a further operating mode. For this purpose, the sixth shifting element F is to be closed, whereby the drive shaft GW1 is driven by the first element E11 of the first planetary gear set P1, while the electric machine EM can support the torque of the internal combustion engine VKM on the third element E32 of the second planetary gear set P2. An output then takes place via the second element E21 of the first planetary gear set P1 and the second element E22 of the second planetary gear set P2 on the output shaft GWA, with the third element E31 of the first planetary gear set P1 and the first element E12 of the second planetary gear set P2 being non-rotatably connected thereto couple the first planetary gear set P1 and the second planetary gear set P2 with one another. In this way, starting off for reversing can be represented.

In addition, a speed reduction of the electric machine EM can be designed in mechanical or hybrid operation: after a torque-assisted shift from third gear 3 to fourth gear via the electric machine EM or after a start-up of the internal combustion engine ICE into fourth gear, hybrid driving occurs the first variant 4.1 of the fourth gear. In order to lower the speed of the electric machine EM in fourth gear at higher driving speeds, it is possible to switch from the first variant 4.1 of the fourth gear to the second variant 4.2, in which the rotor R has a lower speed. This switchover takes place while the tractive force is maintained via the internal combustion engine ICE with the third shifting element C closed. For this purpose, the first shifting element A, which is then unloaded, is disengaged and the second shifting element B, which is also unloaded, is engaged, with the speed being adjusted in each case by speed control of the electric machine EM.

Switching to the second variant 4.2 also has the advantage that the internal combustion engine ICE can be decoupled at any time by opening the third shift element C even without the presence of an additional separating clutch, while the electric machine EM drives or brakes the vehicle. Furthermore, the second variant 4.2 of the fourth gear is required in order to be able to implement a power shift into the fifth gear 5. In addition, when the vehicle is slowing down, a downshift from fourth gear to third gear 3 can be prepared by first changing from the second variant 4.2 to the first variant 4.1, while the internal combustion engine ICE receives the traction when the third shift element C is closed. In the first variant 4.1 of the fourth gear, the first shifting element A is then in turn closed, which is required in order to support the tractive force via the electric machine EM when shifting down from fourth gear to third gear 3 .

With the gearboxes G off 3 and 5 In addition, due to the design of the first switching element A as a non-positive switching element, starting in the charging mode described above can also be implemented via the first switching element A by this being closed with slipping during generator operation of the electric machine EM. Accordingly, the first switching element A functions in this case as an integrated starting element, so that starting from the charging mode is possible without delay.

With the gears G from the 4 and 5 , in which the second shifting element B is present as a non-positive shifting element, shifting between gears E1 and E2 can also be shifted at least under partial power. So with the variant from 4 Train upshifts and train downshifts between the gears E1 and E2 each take place under load. If the first shifting element A is then also implemented as a non-positive shifting element, as is the case with the transmission G 5 If this is the case, shifts between gears E1 and E2 can also be designed to be fully power shiftable. In this case, power upshifts, power downshifts, overrun upshifts and overrun downshifts can be performed under load.

Finally show the 10 until 15 Possible modifications of the transmission G from the 2 until 8th . These modification options relate to other integration options for the electric machine EM. So is in 10 the electric machine EM is not placed coaxially to the respective wheel set RS of the transmission G--not shown in detail here--but is arranged off-axis. A connection is made via a spur gear SRS, which is composed of a first spur gear SR1 and a second spur gear SR2. The first spur gear SR1 is connected to the third element E32 of the second planetary gearset P2 and the second element E23 of the third planetary gearset P3 on the part of the respective gearset RS. The spur gear SR1 then meshes with the spur gear SR2, which is placed on an input shaft EW of the electric machine EM in a rotationally fixed manner, which establishes the connection to the rotor of the electric machine EM—not shown here—within the electric machine EM.

Even with the possibility of modification 11 the electric machine EM is placed off-axis to the respective wheel set RS of the respective transmission G. In contrast to the previous variant after 10 However, a connection is not made via a spur gear stage, but via a traction drive ZT. This traction mechanism ZT can be designed as a belt or chain drive. On the part of the respective wheel set RS, the traction drive ZT is then connected to the third element E32 of the second planetary gear set P2 and the second element E23 of the third planetary gear set P3. A coupling to an input shaft EW of the electric machine EM is then produced via the traction drive ZT, which in turn makes a connection to the rotor of the electric machine within the electric machine EM.

In the case of the possibility of modification 12 An integration of the electric machine EM, which is offset from the axis of the respective wheel set RS, is implemented via a planetary stage PS and a spur gear stage SRS. The planetary stage PS is connected downstream of the wheel set RS, with the spur gear stage SRS being provided on the output side of the planetary stage PS, via which the connection to the electric machine EM is established. The planetary stage PS consists of a ring gear HO, a planet carrier PT and a sun gear SO, with the planet carrier PT rotatably guiding at least one planet gear PR, which meshes with both the sun gear SO and the ring gear HO.

In the present case, the planet carrier PT is connected to the third element E32 of the second planetary gear set P2 and the second element E23 of the third planetary gear set P3 on the part of the respective gear set RS. In contrast, the ring gear HO is permanently fixed to the non-rotatable component GG, while the sun gear SO is non-rotatably connected to a first spur gear SR1 of the spur gear stage SRS. The first spur gear SR1 then meshes with a second spur gear SR2 of the spur gear stage SRS, which is provided in a torque-proof manner on an input shaft EW of the electric machine EM. In this case, the electric machine EM is connected to the wheel set RS via two transmission stages.

Even with the possibility of modification 13 the electric machine EM is integrated by the wheel set RS via a planetary stage PS and a spur gear stage SRS. The possibility of modification largely corresponds to the variant 12 , with the difference that in the planetary stage PS now the sun gear SO is fixed to the non-rotatable component GG, while the ring gear HO is non-rotatably connected to the first spur gear SR1 of the spur gear stage SRS. Specifically, the ring gear HO and the first spur gear SR1 are preferably formed in one piece, in that the ring gear HO is equipped with teeth on an outer circumference. For the rest, the possibility of modification corresponds to 13 otherwise according to the variant 12 , so that reference is made to what has been described here.

Furthermore shows 14 another possible modification of the transmission G from the 2 until 8th , the electric machine EM also being integrated here via a spur gear stage SRS and a planetary stage PS. In contrast to the previous variant after 13 However, the gear set RS is first followed by the spur gear stage SRS, while the planetary stage PS is provided in the power flow between the spur gear stage SRS and the electric machine EM. The planetary stage PS also again includes the elements ring gear HO, planetary carrier PT and sun gear SO, with the planetary carrier PT having several planets wheels PR1 and PR2 are rotatably mounted, each of which meshes with both the sun gear SO and the ring gear HO.

As in 14 As can be seen, a first spur gear SR1 of the spur gear stage SRS is non-rotatably connected to the respective gear set RS, this connection being completed on the third element E32 of the second planetary gear set P2 and the second element E23 of the third planetary gear set P3. The first spur gear SR1 meshes with a second spur gear SR2 of the spur gear stage SRS, which is non-rotatably connected to the planet carrier PT of the planetary stage PS. The ring gear HO is permanently fixed to the non-rotatable component GG, while the sun gear SO is non-rotatably provided on an input shaft EW of the electric machine EM.

Finally still shows 15 another possible modification of the transmission G from the 2 until 8th , This modification possibility essentially according to the previous variant 14 is equivalent to. The only difference is that now the sun gear SO of the planetary stage PS is permanently fixed to the non-rotatable component GG, while the ring gear HO of the planetary stage PS is non-rotatably connected to the input shaft EW of the electric machine EM. For the rest, the possibility of modification corresponds to 15 otherwise according to the variant 14 , so that reference is made to what has been described here.

The execution of the second switching element B and / or the first switching element A according to 3 or. 4 or. 5 can in an analogous manner with the other variants after the 6 until 8th Find application. Furthermore, the in 6 shown embodiment of the third switching element C and the sixth switching element F can also be realized as individual switching elements in the other variants.

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

G

transmission

RS

wheelset

GG

Non-rotatable component

P1

First planetary gear set

E11

First element of the first planetary gear set

E21

Second element of the first planetary gear set

E31

Third element of the first planetary gear set

p2

Second planetary gear set

E12

First element of the second planetary gear set

E22

Second element of the second planetary gear set

E32

Third element of the second planetary gear set

P3

Third planetary gear set

E13

First element of the third planetary gear set

E23

Second element of the third planetary gear set

E33

Third element of the third planetary gear set

A

First switching element

B

Second switching element

C

Third switching element

D

Fourth switching element

E

Fifth switching element

f

Sixth switching element

SP1

switching element pair

SP2

switching element pair

1

First course

2

Second gear

3

Third gear

4.1

Fourth gear

4.2

Fourth gear

4.3

Fourth gear

4.4

Fourth gear

4.5

Fourth gear

4.6

Fourth gear

4.7

Fourth gear

4.8

Fourth gear

4.9

Fourth gear

5

Fifth gear

6

Sixth gear

E1

first course

E2

second gear

EDA-R

Reverse drive mode

GW1

drive shaft

GW1-A

junction

GWA

output shaft

GWA-A

junction

EM

electric machine

S

stator

R

rotor

SRS

spur gear stage

SR1

spur gear

SR2

spur gear

hp

planetary level

HO

ring gear

pt

planetary web

PR

planet wheel

PR1

planet wheel

PR2

planet wheel

SO

sun gear

ZT

traction drive

VKM

internal combustion engine

TS

torsional vibration damper

Inc

differential gear

DW

drive wheels

Claims (14)

Transmission (G) for a motor vehicle, comprising an electric machine (EM), an input shaft (GW1), an output shaft (GWA), and a first planetary gear set (P1), a second planetary gear set (P2) and a third planetary gear set (P3), wherein the first, the second and the third planetary gear set (P1, P2, P3) each have a first element (E11, E12, E13), a second element each (E21, E22, E23) and a third element each (E31, E32, E33). ), wherein the first element (E11, E12, E13) is formed by a respective sun gear of the respective planetary gearset (P1, P2, P3), the second element (E21, E22, E23) in the case of a minus planetary gearset by each a planet carrier and, in the case of a plus planetary gear set, by a ring gear of the respective planetary gear set (P1, P2, P3), the third element (E31, E32, E33) being formed by the respective ring gear and in the case of a minus planetary gear set a plus planetary set through the respective planetary web of the respective planetary gear set zes (P1, P2, P3) is formed, wherein a first (A), a second (B), a third (C), a fourth (D), a fifth (E) and a sixth switching element (F) are provided , through the selective actuation of which six gears between the input shaft (GW1) and the output shaft (GWA) can be represented, and wherein a rotor (R) of the electric machine (EM) on the input shaft (GW1), the output shaft (GWA) or at least one of the Elements (E11, E12, E13, E21, E22, E23, E31, E32, E33) of the planetary gear sets (P1, P2, P3) is connected, characterized in that - that the third element (E32) of the second planetary gear set (P2) and the second element (E23) of the third planetary gearset (P3) is connected to one another in a rotationally fixed manner, - that the output shaft (GWA) is rotationally fixed to the second element (E21) of the first planetary gearset (P1) and the second element (E22) of the second planetary gearset (P2). interconnected, - that the third element (E31) of the first planetary gear set (P1) and the first element (E12) of the second planetary gear set (P2) are connected to one another in a torque-proof manner and can be fixed together via the first switching element (A), - that the first element (E11) of the first planetary gear set (P1) can be fixed by means of the second switching element (B), - and that the drive shaft (GW1) can be connected in a rotationally fixed manner to the output shaft (GWA) via the third shifting element (C) and can be connected in a rotationally fixed manner to the first element (E11) of the first planetary gear set (P1) by means of the sixth shifting element (F). gear (G) after claim 1 , characterized in that the first element (E13) of the third planetary gear set (P3) is non-rotatably connected to the third element (E31) of the first planetary gear set (P1) and the first element (E12) of the second planetary gear set (P2), and that the Drive shaft (GW1) can also be connected via the fourth shifting element (D) in a torque-proof manner to the third element (E32) of the second planetary gear set (P2) and the second element (E23) of the third planetary gear set (P3) and by means of the fifth shifting element (E) in a torque-proof manner the third element (E33) of the third planetary gear set (P3) can be brought into connection. gear (G) after claim 1 , characterized in that the third element (E33) of the third planetary gear set (P3) is non-rotatably connected to the drive shaft (GW1), and that the fourth switching element (D) when actuated, the first element (E13) and the second element (E23) of the third planetary gear set (P3) or the second element (E23) and the third element (E33) of the third planetary gear set (P3) rotatably connected to one another, whereas the first element (E13) of the third planetary gear set (P3) via the fifth switching element (E) rotatably connected to the third element (E31) of the first planetary gear set (P1) and the first element (E12) of the second planetary gear set (P2). Gear (G) according to one of Claims 1 until 3 , characterized in that the rotor (R) the electric machine (EM) is non-rotatably connected to the third element (E32) of the second planetary gear set (P2) and the second element (E23) of the third planetary gear set (P3) or via at least one transmission step to the third element (E32) of the second planetary gear set ( P2) and the second element (E23) of the third planetary gear set (P3) is connected. gear (G) after claim 2 or 3 , characterized in that by selectively closing the six switching elements (A, B, C, D, E, F) - a first gear (1) between the input shaft (GW1) and the output shaft (GWA) by actuating the first (A ) and the sixth shifting element (F), - a second gear (2) between the input shaft (GW1) and the output shaft (GWA) by engaging the first (A) and the fifth shifting element (E), - a third gear (3) between the input shaft (GW1) and the output shaft (GWA) by actuating the first (A) and the fourth switching element (D), - a fourth gear between the input shaft (GW1) and the output shaft (GWA) in a first variant (4.1) by closing the first (A) and the third switching element (C), in a second variant (4.2) by closing the second (B) and the third switching element (C), in a third variant (4.3) by actuating the third (C ) and the fourth switching element (D), in a fourth variant (4.4) by closing the third ( C) and the fifth switching element (E), in a fifth variant (4.5) by actuating the third (C) and the sixth switching element (F), in a sixth variant (4.6) by closing the fourth (D) and the fifth switching element (E), in a seventh variant (4.7) by actuating the fourth (D) and the sixth switching element (F), in an eighth variant (4.8) by closing the fifth (E) and the sixth switching element (F) and in one ninth variant (4.9) by actuating the third shifting element (C), - a fifth gear (5) by actuating the second (B) and the fourth shifting element (D), - and a sixth gear (6) by engaging the second (B ) and the fifth switching element (E). gear (G) after claim 4 , characterized in that a first gear (E1) between the rotor (R) of the electric machine (EM) and the output shaft (GWA) by closing the first switching element (A) and a second gear (E2) between the rotor (R) of the electric machine (EM) and the output shaft (GWA) by actuating the second switching element (B). Transmission (G) according to one of the preceding claims, characterized in that one or more of the shifting elements (A, B, C, D, E, F) are each implemented as a positive-locking shifting element. Transmission (G) according to one of the preceding claims, characterized in that the first shifting element (A) and/or the second shifting element (B) is designed as a non-positive shifting element. Transmission (G) according to one of the preceding claims, characterized in that the third shifting element (C) and the sixth shifting element (F) are combined to form a shifting element pair (SP1), to which an actuating element is assigned, with the actuating element moving out of a neutral position on the one hand the third switching element (C) and on the other hand the sixth switching element (F) can be actuated. Transmission (G) according to one of the preceding claims, characterized in that the fourth shifting element (D) and the fifth shifting element (E) are combined to form a shifting element pair (SP2), to which an actuating element is assigned, with the actuating element being used to move out of a neutral position on the one hand the fourth switching element (D) and on the other hand the fifth switching element (E) can be actuated. Transmission according to one of the preceding claims, characterized in that the first shifting element and the second shifting element are combined to form a shifting element pair, to which an actuating element is assigned, the first shifting element on the one hand and the second shifting element on the other hand being operable via the actuating element from a neutral position. Motor vehicle drive train for a hybrid or electric vehicle, comprising a transmission (G) according to one or more of Claims 1 until 11 . Method for operating a transmission (G) according to claim 4 , characterized in that only the fourth switching element (D) is closed to represent a charging operation or a starting operation. Method for operating a transmission (G) according to claim 4 , characterized in that the sixth switching element (F) is closed to represent a starting mode for reversing when driven via the drive shaft (GW1).

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