DE102017216320A1 - Transmission for a motor vehicle - Google Patents

Abstract

The invention relates to a transmission (G) for a motor vehicle, comprising an electric machine (EM), a drive shaft (GW1), an output shaft (GW2), two planetary gear sets (P1, P2) and at least five shift elements (K1, K2, K3, K4 , K5), wherein by selectively operating the at least five switching elements (K1, K2, K3, K4, K5) different gears between the drive shaft (GW1) and the output shaft (GW2) switchable and also in conjunction with the electric machine (EM) different modes of operation can be represented, and drive train for a motor vehicle with such a transmission (G) and method for operating derselbigen.

Description

The invention relates to a transmission for a motor vehicle, comprising an electric machine, a drive shaft, an output shaft, and a first planetary gear set and a second planetary gear set, wherein the planetary gear sets each comprise a plurality of elements, wherein a first, a second, a third, a fourth and a fifth switching element are provided, and wherein a rotor of the electric machine is connected to the drive shaft, to 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 wheelset, also have one or more electric machines. The transmission is usually designed to be more continuous, d. H. There are several different ratios as gears between a drive shaft and an output shaft by operating corresponding switching elements switchable, this is preferably done automatically. Depending on the arrangement of the switching elements, these are clutches or brakes. The transmission is used to implement a traction power supply of a prime mover of the motor vehicle in terms of various criteria suitable. The gears of the transmission are usually used in conjunction with the at least one electric machine to represent a purely electric driving. Often, the at least one electric machine can also be incorporated in the transmission to display different modes of operation in different ways.

From the DE 10 2013 013 947 A1 goes out a gearbox for a motor vehicle, which is composed of two planetary gear sets and an electric machine. The two planetary gear sets are each formed by the elements sun gear, planet web and ring gear, wherein also a total of five switching elements are provided, via which different power flow guides can be represented on the planetary gear sets. Thus, several gears between a drive shaft and an output shaft of the transmission can be realized when driven by an upstream prime mover and two gears when driven by the electric machine.

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

This object is achieved on the basis of the preamble of claim 1 in conjunction with its characterizing features. The following dependent claims give each advantageous embodiments of the invention. A motor vehicle drive train for a hybrid vehicle is also subject matter of claim 13. Furthermore, the claim 14, a method for operating a transmission to the object.

According to the invention, a transmission comprises an electric machine, a drive shaft, an output shaft and a first planetary gear set and a second planetary gear set. The planetary gear sets comprise several elements, wherein a first, a second, a third, a fourth and a fifth switching element are provided by their selective actuation different power flow guides can be represented by switching different gears.

For the purposes of the invention, a "shaft" is understood to mean a rotatable component of the transmission via which associated components of the transmission are non-rotatably connected to one another or via which such a connection is produced upon actuation of a corresponding switching element. The shaft can connect the components axially or radially or both axially and radially with each other. Thus, the respective shaft can also be present as an intermediate piece, via which a respective component is connected radially, for example.

By "axial" in the context of the invention is meant an orientation in the direction of an axis along which the planetary gear sets are arranged coaxially to one another. By "radial" is then to be understood an orientation in the diameter direction of a shaft, which lies on this axis.

Preferably, the output shaft of the transmission has a toothing, via which the output shaft is then operatively connected in the motor vehicle drive train with an axially parallel to the output shaft arranged differential gear. Here, the toothing is preferably provided at a connection point of the output shaft, said connection point of the output shaft is preferably axially in the region of one end of the transmission, on which a connection point of the drive shaft is provided. This type of arrangement is particularly suitable for use in a motor vehicle with a transversely oriented to the direction of travel of the motor vehicle drive train.

The planetary gear sets are preferably arranged axially following the connection point of the drive shaft in the order of the first planetary gearset and the second planetary gearset. For the purposes of the invention, however, can also be made a different arrangement.

The invention now includes the technical teaching that the drive shaft is rotatably connected to the first element of the second planetary gear set and can be rotatably connected via the first switching element with the second element of the first planetary gear in combination. The output shaft is non-rotatably connected to the third element of the first planetary gear set in connection and can be non-rotatably connected by means of the second switching element with the second element of the second planetary gear set. Furthermore, a rotor of the electric machine can be connected via the third switching element to the drive shaft and brought by means of the fourth switching element with the output shaft in connection. Further, the second element of the first planetary gear set and the second element of the second planetary gear set can be rotatably connected to each other via the fifth switching element. Finally, the first element of the first planetary gear set and the third element of the second planetary gear set are fixed.

In other words, therefore, the drive shaft is permanently connected in a rotationally fixed manner to the first element of the second planetary gear set, while the output shaft is permanently non-rotatably connected to the third element of the first planetary gear set. In addition, the first element of the first planetary gear set and the third element of the second planetary gear set are each permanently fixed and are thus constantly prevented from rotating. In this case, the first element of the first planetary gear set and the third element of the second planetary gear set are particularly preferably non-rotatably connected to one another and fixed together.

Upon actuation of the first switching element, the drive shaft is non-rotatably connected to the second element of the first planetary gear set, whereas the second switching element in the closed state, the output shaft and the second element of the second planetary gear rotatably connected to each other brings. A closing of the third switching element has a rotationally fixed connection of the rotor of the electric machine with the drive shaft result, while the fourth switching element in the closed state, the rotor of the electric machine and the output shaft rotatably connected to each other. Finally, by closing the fifth switching element, the second element of the first planetary gear set and the second element of the second planetary gear set rotatably connected to each other.

A respective rotationally fixed connection of the rotatable components of the transmission is realized according to the invention preferably via one or more intermediate waves, which may also be present as a short intermediate pieces in spatially dense position of the components. In concrete terms, the components which are permanently connected to one another in a rotationally fixed manner can each be present either as individual components which are connected to one another in a torque-proof manner or also in one piece. In the second-mentioned case, the respective components and the possibly existing shaft are then formed by a common component, wherein this is especially realized just when the respective components are spatially close to each other in the transmission.

In the case of components of the transmission which are only connected to one another by actuation of a respective switching element, a connection is likewise preferably realized via one or more intermediate shafts.

A setting is carried out 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 rotatably connected thereto component. In the present case, the first element of the first planetary gear set and the third element of the second planetary gear set are permanently fixed.

In the case of the transmission, the first, second, third, fourth and fifth shifting elements are in the form of clutches which, when actuated, respectively match the respective rotatable components of the transmission with respect to one another in their rotational movements and subsequently connect them to one another in a torque-proof manner.

Preferably, the first, the third and the fourth switching element are arranged axially on one of the connection point of the drive shaft facing side of the first planetary gear, in which case the first switching element in particular axially adjacent to the first planetary gear and then axially followed by the third and the fourth switching element. In this case, the third and the fourth switching element can also lie axially at substantially the same height. In contrast, the second and the fifth switching element are axially preferably placed between the first planetary gear set and the second planetary gear set, wherein the second switching element in this case lies in particular axially between the first planetary gear set and the fifth switching element.

On the drive side, a separating clutch can additionally be provided which, in the actuated state, rotatably connects the drive shaft to a connecting shaft, which in turn is coupled to the drive machine arranged upstream of the transmission. This separating clutch can in principle be designed as a non-positive or as a form-locking switching element, but is particularly preferred as a friction clutch.

Overall, an inventive transmission is characterized by a compact design, low component loads, good gear efficiency and low losses.

In the transmission according to the invention four gears between the drive shaft and the output shaft can be realized by selectively closing two switching elements. This results in a first gear between the drive shaft and the output shaft in a first variant by operating the second and the fourth switching element, wherein the first gear can also be represented in a second variant by closing the second and the third switching element. Furthermore, a second gear between the drive shaft and the output shaft in a first variant by actuation of the fourth and the fifth switching element and in a second variant by closing the third and the fifth switching element is switchable. Further, a third speed between the input shaft and the output shaft can be switched by operating the third and fourth shift elements. Finally, a fourth gear between the input shaft and the output shaft results in a first variant by closing the first and the fourth switching element and in a second variant by actuating the first and the third switching element.

With a suitable choice of stationary gear ratios of the planetary gear sets this is a suitable for the application in the field of a motor vehicle translation series realized. In this case, circuits between the gears can be realized, in which always only the state of two switching elements is to be varied by one of the switching elements involved in the previous course to open and another switching element to represent the subsequent course is to close. This then has the consequence that a shift between the courses can proceed very quickly.

Due to the placement of the electric machine in the transmission and the possible connections of the rotor of the electric machine, different operating modes can be realized in a simple manner:

Thus, a first gear between the rotor and the output shaft for a purely electric driving can be used. In this case, this first gear results by closing the fourth switching element, so that the rotor of the electric machine is connected directly to the output shaft. In this case, a translation of the first gear corresponds to a translation of the third between the drive shaft and output shaft effective gear.

Since a further switching element must always be closed for driving via a prime mover upstream of the transmission, driving over the electric machine can be represented here without the prime mover being coupled. From this purely electric driving then the upstream prime mover in the first variant of the first between the input and output shaft effective gear, in the first variant of the second between the input and output shaft effective gear, in the third between input and output shaft effective gear and in the first variant of the fourth between the input and output shaft effective gear are each started, since the fourth switching element is involved in each of these courses.

As a further mode of operation also a charging operation of an electrical energy storage can be realized by only closed the third switching element and thus a connection of the drive shaft with the electric machine and thus also the upstream drive machine is made with the electric machine. At the same time no frictional connection to the output shaft is made, so that the transmission is in a neutral position. Apart from a loading operation, this can also be used to start the preceding drive machine via the electric machine.

Since the electric machine is coupled in the closed state of the fourth switching element to the output shaft, load circuits can also be realized, in which in each case a support via the electric machine can take place in the course of the circuits. In this case, the synchronization of the closing element to be closed in a circuit element by speed control of the upstream drive machine or by synchronized switching elements or by another, separate synchronization device, such as a transmission brake or a further electric machine. If on the drive side of the drive shaft also provided a disconnect clutch, the inertial mass of the upstream drive machine can be disconnected during synchronization. Specifically, circuits between the first variant of the first, effective between the input and output shaft and the first variant of the second, effective between the input and output shaft gear under load with closed fourth switching element can be realized. The same is possible in load circuits between the first variant of the second, between the input and output shaft effective gear and the third, effective between the input and output shaft gear. Further, load circuits between the third, between the input and output shaft effective gear and the first variant of the fourth, effective between the input and output shaft gear in the closed state of the fourth switching element can be represented.

The transmission according to the invention can also be operated so that when driving a speed reduction of the electric machine is achieved. So can be driven first hybrid in the first variant of the fourth gear by the fourth switching element initially remains closed either by a torque-assisted via the electric machine circuit from third to fourth gear or after a states of the prime mover in the fourth gear. But now to lower a speed of the electric machine in fourth gear at higher speeds, can be switched from the first variant of the fourth gear in the second variant of the fourth gear, since the rotor of the electric machine has a lower speed than in the first variant of the fourth Ganges. This switching takes place while maintaining the traction over the upstream prime mover. First, while the load-free, fourth switching element is designed and subsequently loaded the load-free, third switching element, wherein the speed adjustment takes place by speed control of the electric machine. If, in addition, a separating clutch is provided, via which the drive shaft can be connected on the drive side to a connecting shaft, the upstream drive machine can also be decoupled. The latter makes sense, even if from higher speeds out a recuperation on the electric machine should be done while decoupling the prime mover and off.

Under a "connectability" of the rotor of the electric machine with the respective components of the transmission via the switching elements is to be understood in the context of the invention that the rotor is coupled to an actuation of the respective switching element with the respective component of the transmission, so that then between the rotor the electric machine and the respective component prevails a constant speed dependence. In this case, the electric machine can be arranged either coaxially with the planetary gear sets or offset from the axis to these. In the former case, the rotor of the electric machine can be connected via the respective switching element either directly rotatably connected to the respective component or coupled via one or more intermediate gear ratios with this, the latter allows a cheaper design of the electric machine with higher speeds and lower torque. The at least one translation stage can be designed as a spur gear and / or as a planetary stage.

If, however, the electric machine is provided offset in the axial direction with respect to the planetary gear sets, then a coupling takes place via one or more intermediate gear ratios and / or a traction drive. The one or more translation stages can also be realized in detail either as a spur gear or as a planetary stage. A traction drive may be either a belt drive or a chain drive.

According to a further embodiment possibility of the invention exactly one electric machine is provided, which is set up to drive the output shaft. In this case, the transmission according to the invention thus has only one electric machine, which can also act as a drive of the output shaft. This has the advantage that thus a compact design and a low production cost of the transmission can be realized.

According to a further embodiment of the invention, the rotor of the electric machine can also be connected via a sixth switching element with the second element of the first planetary gear set. Particularly preferably, this sixth switching element is provided axially on one of the connection point of the drive shaft facing side of the first planetary gear set and is further preferably axially between the junction of the drive shaft and the fourth switching element.

By providing the additional, sixth switching element in the transmission according to the invention then a further variant of the first active between input and output shaft gear, another variant of the second between the output shaft effective gear and two other variants of the fourth between the input and output shaft effective gear will be realized. Thus, the first, effective between the input and output shaft gear in a third variant by closing the second and the sixth switching element, the second, between the input and output shaft effective gear results in a third variant by operating the fifth and the sixth switching element, the fourth, effective between input and output shaft gear in a third variant by closing the first and the sixth switching element and in a fourth variant by operating the third and the sixth switching element.

In addition, in addition, a second gear can be realized, which is effective between the rotor of the electric machine and the output shaft. This second gear is thereby switched by closing the sixth switching element, so that the electric machine is then connected via the first planetary gear set to the output shaft. Starting from this second gear can then take a states of the upstream engine in the third variant of the first gear, the third variant of the second gear and the third and the fourth variant of the fourth gear, since the sixth Switching element is also involved in each of these gears.

Furthermore, when the sixth switching element is provided, the transmission according to the invention can furthermore be operated in such a way that a speed reduction of the electric machine is achieved during driving. So can be driven first hybrid in the first variant of the fourth between the input and output shaft effective gear by the fourth switching element initially closed either by a torque-assisted via the electric machine circuit from third to fourth gear or after a states of the prime mover remains. But now to lower a speed of the electric machine in fourth gear at higher speeds, can be switched from the first variant of the fourth gear in the third variant of the fourth gear, since the rotor of the electric machine has a lower speed than in the first variant of the fourth gear. This switching takes place while maintaining the traction over the upstream prime mover. First, while the load-free, fourth switching element is designed and subsequently loaded the load-free, sixth switching element, wherein the speed adjustment takes place by speed control of the electric machine.

In this case, to decouple the upstream prime mover no clutch is required because the upstream prime mover can be decoupled in the third variant of the fourth, effective between input and output shaft gear by opening the first switching 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, when the vehicle becomes slower, a downshift from the fourth gear active between the drive shaft and the output shaft to the third gear active between the drive shaft and the output shaft can be prepared by first changing from the third variant to the first variant of the fourth gear and thereby the traction force when the first one is closed Switching element is obtained via the upstream drive machine. In the first variant of the fourth gear, in turn, the fourth switching element is then closed, which is required to support the traction over the electric machine in the course of the downshift from fourth to third gear.

According to an alternative embodiment for execution with exactly one electric machine, a second electric machine may be provided, the rotor of which is permanently connected to the drive shaft. By such a configuration, the functionality of the transmission can be further increased.

In a further development of the invention, one or more switching elements are each realized as a form-locking switching element. In this case, the respective switching element is preferably designed either as a claw switching element or as a blocking synchronization. Form-locking switching elements have the advantage over non-positive switching elements that occur in the open state lower drag losses, so that it is possible to achieve a better efficiency of the transmission. In particular, in the transmission according to the invention all switching elements are realized as form-fitting switching elements, so that the lowest possible drag losses can be achieved.

The two planetary, if it allows a connection of the elements, in the context of the invention each present as a minus planetary gear set, wherein it is a sun gear at the first element of the respective planetary gear, at the second element of the respective planetary gear around a planet web and the third element of the respective planetary gear is a ring gear. A minus planetary set is composed in a manner known in principle to the person skilled in the art from the elements sun gear, planet carrier and ring gear, wherein the planet carrier at least one, but preferably several planetary gears rotatably mounted, in each case with both the sun gear, and the combing the surrounding ring gear.

Alternatively, but one or both planetary gear sets, if it allows the connection of the respective elements, as a plus-planetary gear, wherein it is the first element of the respective planetary gear then a sun gear, in the second element of the respective planetary gear around a ring gear and the third element of the respective planetary gear set is a planetary land. In a plus-planetary gear set the elements sun gear, ring gear and planetary gear are also present, the latter at least one pair of planetary leads, in which one planetary gear with the inner sun gear and the other planet gear meshing with the surrounding ring gear, and the planet gears mesh with each other.

Where there is a connection of the individual elements, a minus planetary gear set can be converted into a plus-planetary gear set, in which case compared to the design as a minus planetary gear set the Hohlrad- and the Planetensteganbindung to swap with each other, and a Getriebestandübersetzung is to increase by one. Conversely, a plus planetary gear set could be replaced by a minus planetary gear set, if the connection of the elements of the transmission makes this possible. It would then be compared to the plus-planetary gear set also to swap the Hohlrad- and the Planetensteganbindung with each other, and to reduce a Getriebestandübersetzung by one. Preferably, however, the first planetary gear set is designed as a minus planetary gear set, while the second planetary gear set is present as a plus-planetary gear set.

In a further development of the invention, at least two switching elements are each combined to a pair of switching elements, which is assigned to each a common actuator, wherein on the one actuating element from a respective neutral position on the one hand, the one switching element and on the other hand, the other switching element of the respective switching element pair can be actuated. This is realized in switching elements of the transmission, which have a common shaft and are not simultaneously operated in one gear, and has the advantage that thereby reduces the number of actuators and thus the manufacturing cost can be reduced.

Depending on the specific embodiment of the transmission while the first and third switching element and / or the second and the fifth switching element and / or the fourth and the sixth switching element can be combined in pairs and each have a common actuator.

In the context 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 serves to design a start-up process by allowing a slip speed between the internal combustion engine and the drive shaft of the transmission. In this case, one of the switching elements of the transmission or the possibly existing separating clutch can be designed as such a starting element by being present as a friction switching 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 vehicle and is then arranged between a drive engine of the motor vehicle designed in particular as an internal combustion engine and further components of the drive train following in the direction of force flow to drive wheels of the motor vehicle. Here, the drive shaft of the transmission is either permanently rotatably coupled to a crankshaft of the internal combustion engine or connected via an intermediate disconnect clutch or a starting element with this, between the internal combustion engine and transmission also a torsional vibration damper can be provided. 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 also a connection to a longitudinal differential may be present, via which a distribution takes place on a plurality of driven axles of the motor vehicle. The differential gear or the longitudinal differential can be arranged with the transmission in a common housing. Likewise, a torsional vibration damper can also be integrated into this housing.

The fact that two components of the transmission are non-rotatably "connected" or "coupled" or "communicate with one another" means, for the purposes of the invention, a permanent coupling of these components, so that they can not rotate independently of each other. In this respect, no switching element is provided between these components, in which it may be elements of the planetary gear sets and / or shafts and / or a non-rotatable component of the transmission, but the corresponding components are rigidly coupled together.

If, by contrast, a switching element is provided between two components, then these components are not permanently coupled to one another in a rotationally fixed manner, but instead a rotationally fixed coupling is made by actuating the intermediate switching element. In this case, an actuation of the switching element in the sense of the invention means that the relevant switching element is transferred into a closed state and, as a result, the components directly coupled to it in their rotational movements equal to one another. In the case of an embodiment of the relevant switching element as a form-locking switching element on this directly rotatably interconnected components are running at the same speed, while in the case of a non-positive switching element can also exist after pressing desselbigen speed differences between the components. This intentional or unwanted state is still referred to in the context of the invention as a rotationally fixed connection of the respective components via the switching element.

The invention is not limited to the specified combination of the features of the main claim or the claims dependent thereon. It also results in ways to combine individual features, 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 by use of reference numerals is not intended to limit the scope of the claims.

• 1 eine schematische Ansicht eines Kraftfahrzeugantriebsstranges, in welchem ein erfindungsgemäßes Getriebe zur Anwendung kommt;
• 2 eine schematische Ansicht eines Getriebes entsprechend einer ersten Ausführungsform der Erfindung;
• 3 ein beispielhaftes Schaltschema des Getriebes aus 2;
• 4 eine schematische Ansicht eines Getriebes entsprechend einer zweiten Ausführungsform der Erfindung;
• 5 ein beispielhaftes Schaltschema des Getriebes aus 4; und
• 6 bis 11 jeweils eine schematische Darstellung je einer Abwandlungsmöglichkeit der Getriebe aus den 2 und 4.

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, in which a transmission according to the invention is used;
• 2 a schematic view of a transmission according to a first embodiment of the invention;
• 3 an exemplary circuit diagram of the transmission 2 ;
• 4 a schematic view of a transmission according to a second embodiment of the invention;
• 5 an exemplary circuit diagram of the transmission 4 ; and
• 6 to 11 in each case a schematic representation depending on a modification possibility of the transmission from the 2 and 4 ,

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

Out 2 is a schematic representation of the transmission G according to a first embodiment of the invention. As can be seen, the gearbox sits down G from a wheelset RS and an electric machine EM together, in common in the housing of the transmission G are arranged. The wheelset RS includes two planetary gear sets P1 and P2 where each of the planetary gear sets P1 and P2 one first element each E11 respectively. E12 , a second element each E21 respectively. E22 and a third element each E31 respectively. E32 having. The respective first element E11 respectively. E12 is in each case by a respective sun gear of the respective planetary gear set P1 respectively. P2 formed while the second element E21 of the first planetary gear set P1 as a planetary bridge and the third element E31 of the first planetary gear set P1 is present as a ring gear. On the other hand, that's the second element E22 of the second planetary gear set P2 as a ring gear and the third element E32 of the second planetary gear set P2 designed as a planetary bridge.

In the present case, therefore, is the first planetary gear P1 as a minus planetary gear set, the planetary web at least one planetary gear rotatably mounted, which is in mesh with both the radially inner sun gear, as well as the radially surrounding ring gear. But are particularly preferred in the first planetary gear P1 provided several planetary gears. In contrast, the second planetary gear set P2 realized as a plus planetary gear, in which case the planetary gear at least one planetary rotatably mounted, from the planetary gears a planetary gear with the radially inner sun gear and a planet gear with the radially surrounding ring gear meshing, and the planet gears mesh with each other. However, even the second planetary gear set P2 in particular provided several Planetenradpaare.

If it allows the connection, the first planetary gear set could P1 be executed as a plus-planetary gear set, in which compared to the execution as a minus planetary gear set then the second element E21 through the ring gear and the third element E31 formed by the planetary bridge and also a gearbox ratio must be increased by one. Conversely, could also be the second planetary gear P2 if it allows a connection of the elements to be realized as a minus planetary gear. Compared to the version as a plus-planetary gear set, however, would then be the second element E22 through the planetary bridge and the third element E32 formed by the ring gear and also a Getriebestandübersetzung be reduced by one.

As in 2 can be seen, includes the gearbox G a total of five switching elements in the form of a first switching element K1 , a second switching element K2 , a third switching element K3 , a fourth switching element K4 and a fifth switching element K5 , Here are the switching elements K1 . K2 . K3 . K4 and K5 each designed as a form-fitting switching elements and are preferably before as claw switching elements. In addition, the first switching element K1 , the second switching element K2 , the third switching element K3 , the fourth switching element K4 and the fifth switching element K5 designed here as couplings.

A drive shaft LV1 of the transmission G is non-rotatable with the first element E12 of the second planetary gear set P2 connected and can via the first switching element K1 rotatably with the second element E21 of the first planetary gear set P1 be associated. An output shaft GW2 of the gearbox is rotationally fixed with the third element E31 of the first planetary gear set P1 in conjunction and can also by closing the second switching element K2 rotatably with the second element E22 of the second planetary gear set P2 get connected. Furthermore, the drive shaft LV1 by closing the third switching element K3 rotatably with a rotor R the electric machine EM which are coaxial with the planetary gear sets P1 and P2 is arranged and its stator S permanently on a non-rotatable component GG of the transmission G is fixed, wherein it is in the rotationally fixed component GG in particular to the housing or a part of the housing of the transmission G is. In addition, the rotor can R the electric machine EM still by means of the fourth switching element K4 rotatably with the output shaft GW2 be associated.

As further in 2 it can be seen, the second element E21 of the first planetary gear set P1 and the second element E22 of the second planetary gear set P2 by closing the fifth switching element K5 rotatably connected to each other. Finally, the first element E11 of the first planetary gear set P1 and the third element E32 of the second planetary gear set P2 rotatably connected to each other and together on the non-rotatable component GG fixed so that both the first element E11 of the first planetary gear set P1 as well as the third element E32 of the second planetary gear set P2 constantly be prevented from rotating.

Both the drive shaft LV1 , as well as the output shaft GW2 each form one connection point Level 1-A respectively. GW2-A out, with the connection point Level 1-A in the motor vehicle drive train 1 a connection to the internal combustion engine VKM serves while the gearbox G at the junction GW2-A with the following differential gear AG connected is. The connection point Level 1-A the drive shaft LV1 is at one axial end of the transmission G designed, with the connection point GW2-A the output shaft GW2 is in the range of the same axial end and this transverse to the junction Level 1-A the drive shaft LV1 is aligned. The two planetary gear sets P1 and P2 are on the connection point Level 1-A the drive shaft LV1 axially following in the order of the first planetary gear set P1 and second planetary gear set P2 arranged.

As well as out 2 shows, are the first switching element K1 , the third switching element K3 and the fourth switching element K4 axially on one of the connection points Level 1-A facing side of the first planetary gear set P1 placed, wherein the first switching element K1 while axially adjacent to the first planetary gear P1 is and then then first the third switching element K3 and then the fourth switching element K4 consequences. In addition, the first switching element lie K1 and the third switching element K3 axially adjacent to each other and radially at the same height and have a common - not shown here in the further - actuating element, via which from a neutral position, on the one hand, the first switching element K1 and on the other hand, the third switching element K3 can be operated. In this respect, the first switching element K1 and the third switching element K3 to a pair of switching elements SP1 summarized.

On the other hand, the second switching element K2 and the fifth switching element K5 axially between the first planetary gear set P1 and the second planetary gear set P2 provided, wherein the second switching element K2 while axially between the first planetary gear P1 and the fifth switching element K5 lies. In addition, the second switching element K2 and the fifth switching element K5 axially immediately adjacent to each other and arranged radially substantially at the same height and to a switching element pair SP2 summarized by the second switching element K2 and the fifth switching element K5 a common - also not shown here - is assigned actuating element, via which from a neutral position on the one hand, the second switching element K2 and on the other hand, the fifth switching element K5 can be operated.

The electric machine EM is axially on one of the connection point Level 1-A the drive shaft LV1 facing side of the first planetary gear set P1 arranged and lies axially between the junction Level 1-A the drive shaft LV1 and the connection point GW2-A the output shaft GW2 ,

In 3 is an exemplary circuit diagram for the transmission G out 2 tabulated. As can be seen, this case between the drive shaft LV1 and the output shaft GW2 a total of four courses 1 to 4.2 be realized, which is marked in the columns of the circuit diagram with an X respectively, which of the switching elements K1 . K2 . K3 . K4 and K5 in which of the corridors 1 to 4.2 each is closed. In each of the courses 1 to 4.2 are each two of the switching elements K1 . K2 . K3 . K4 and K5 closed.

As in 3 can be seen, a first gear between the drive shaft LV1 and output shaft GW2 in a first variant 1.1 by actuating the second switching element K2 and the fourth switching element K4 switched, with the first gear between drive shaft LV1 and output shaft GW2 also in a second variant 1.2 by closing the second switching element K2 and the third switching element K3 can be represented. Furthermore, there is a second gear between the drive shaft LV1 and output shaft GW2 in a first variant 2.1 by actuating the fourth switching element K4 and the fifth switching element K5 as well as in a second variant 2.2 by closing the third switching element K3 and the fifth switching element K5 , In addition, a third gear 3 between drive shaft LV1 and output shaft GW2 by actuating the third switching element K3 and the fourth switching element K4 be switched.

Furthermore, there is a fourth, between the drive shaft LV1 and the output shaft GW2 effective gear in a first variant 4.1 by actuating the first switching element K1 and the fourth switching element K4 , where the fourth gear is still in a second variant 4.2 by closing the first switching element K1 and the third switching element K3 can be represented.

Although the switching elements K1 . K2 . K3 . K4 and K5 Each designed as a form-locking switching elements, a switching between the first variant 1.1 the first gear and the first variant 2.1 second gear, between the first variant 2.1 the second gear and the third gear 3 as well as between the third gear 3 and the first variant 4.1 the fourth gear are each realized under load. Reason is that the fourth switching element K4 involved in all these gears, so that in the course of the circuits the output via the electric machine EM can be supported, in the closed state of the fourth switching element K4 directly with the output shaft GW2 is coupled. A synchronization in the circuits can be achieved by an appropriate regulation of the upstream internal combustion engine VKM take place, so that the respective switching element to be interpreted load-free and the closing element to be closed below can be closed without load.

The gear G out 2 can also be used in other operating modes with the help of the electric machine EM operated: so can a purely electric driving in a first gear E1 take place, which between the rotor R the electric machine EM and the output shaft GW2 is effective and the representation of the fourth switching element K4 to convert into a closed state is how out 4 evident. This is when the fourth switching element is closed K4 the electric machine EM directly against rotation with the output shaft GW2 connected, the translation of the first gear E1 Here the translation of the third, between drive shaft LV1 and output shaft GW2 effective gear 3 equivalent.

Advantageously, starting from the first gear E1 a states of the internal combustion engine VKM in one of the corridors 1.1 . 2.1 . 3 and 4.1 be made, since in each of these courses in each case the fourth switching element K4 closed is. In this respect, it is possible to move quickly from purely electric driving to driving via the internal combustion engine or hybrid driving.

Furthermore, by closing the third switching element K3 a charging or starting function can be realized. Because in the closed state of the third switching element K3 is the rotor R the electric machine EM directly against rotation with the drive shaft LV1 coupled and thus with the internal combustion engine VKM , At the same time, however, there is no frictional connection to the output shaft GW2 , where the rotor R and the drive shaft LV1 run fast. In generator operation of the electric machine EM can be an electrical energy storage via the internal combustion engine VKM be charged while in the electric motor operation of the electric machine EM starting the internal combustion engine VKM over the electric machine EM is feasible.

Finally, even a speed reduction of the electric machine EM be designed in mechanical or hybrid operation: after a via the electric machine EM torque-based circuit from third gear to fourth gear or after a start of the internal combustion engine VKM in the fourth gear results in a hybrid driving in fourth gear 4.1 , To the speed of the electric machine EM Lowering in fourth gear at higher speeds, can from the first variant 4.1 the fourth gear in the second variant 4.2 be switched, in which the rotor R has a lower speed. This switching takes place while maintaining the traction over the internal combustion engine VKM , This is then the load-free, fourth switching element K4 designed and also load-free, third switching element K3 inserted, the speed adjustment in each case by speed control of the electric machine EM he follows.

Further shows 4 a schematic representation of a transmission G according to a second embodiment of the invention. This embodiment largely corresponds to the variant 2 , but in contrast to now additionally a sixth switching element K6 is provided, which in the actuated state, the rotor R the electric machine EM and the second element E21 of the first planetary gear set P1 rotatably connected. The sixth switching element K6 , which is designed here as a clutch, is axially on one of the connection point Level 1-A the drive shaft LV1 facing side of the fourth switching element K4 provided, wherein the fourth switching element K4 now axially substantially at the level of the third switching element K3 lies. In the present case are the fourth switching element K4 and the sixth switching element K6 axially immediately adjacent to each other as well as placed radially substantially at the same height and to a pair of switching elements SP3 summarized by the fourth switching element K4 and the sixth switching element K6 a common - not shown - - actuating element is assigned, via which from a neutral position, on the one hand, the fourth switching element K4 and on the other hand, the sixth switching element K6 can be operated. Otherwise, the embodiment corresponds to 4 according to the variant 2 so that reference is made to what has been described.

In 5 is an exemplary circuit diagram of the transmission G out 4 in this case, this circuit diagram substantially corresponds to the circuit diagram 3 equivalent. It is different that by the additional sixth switching element K6 now another variant of the first between drive shaft LV1 and output shaft GW2 effective gear, another variant of the second between drive shaft LV1 and output shaft GW2 effective gear and two other variants of the fourth between drive shaft LV1 and output shaft GW2 effective gear can be displayed. This results in a third variant 1.3 the first gear by operating the second switching element K2 and the sixth switching element K6 , a third variant 2.3 of the second gear by closing the fifth switching element K5 and the sixth switching element K6 , a third variant 4.3 of the fourth gear by operating the first switching element K1 and the sixth switching element K6 and a fourth variant 4.4 of the fourth gear by closing the third switching element K3 and the sixth switching element K6 ,

Also with the transmission G out 4 can the different, in 3 described operating modes are realized. In addition, now can a second gear E2 by closing the sixth switching element K6 be represented, wherein the second gear E2 between the rotor R and the output shaft GW2 is effective. This is the rotor R the electric machine EM then over the first planetary gear set P1 with the output shaft GW2 coupled. Starting from second gear E2 can the internal combustion engine VKM in the corridors 1.3 . 2.3 . 4.3 and 4.4 to be started in each case, as to each of these also the sixth switching element K6 is involved.

In addition, in the transmission G out 4 also a speed reduction of the electric machine EM by switching from the first variant 4.1 in the third variant 4.3 the fourth gear are realized. This is done starting from the first variant 4.1 while maintaining the traction over the internal combustion engine VKM first the load-free fourth switching element K4 designed and also load-free, sixth switching element K6 inserted, with a speed adjustment for representing the load freedoms by speed control of the electric machine EM he follows. Apart from that, by switching to the third variant 4.3 the fourth gear a speed reduction of the rotor R the electric machine EM can achieve this, it is also possible, the internal combustion engine VKM by opening the first switching element K1 Disconnect at any time, if over the electric machine EM driven or braked (recuperation) is to be.

In addition, when the vehicle slows down a shift from fourth gear to third gear 3 be prepared by first of the third variant 4.3 in the first variant 4.1 the fourth gear is changed, while on the internal combustion engine VKM when the first switching element is closed K1 the tensile force is obtained. In the first variant 4.1 the fourth gear is then the fourth switching element K4 closed, over which in the course of the downshift into third gear 3 a support of the tensile force can take place.

Finally show the 6 to 11 Modifications of the transmission G from the 2 and 4 , These modification options relate to other ways of integrating an electric machine EM , So is in 6 the electric machine EM not coaxial with the respective - not shown here - wheelset RS of the transmission G placed but arranged off-axis. A connection is made via a spur gear SRS made up of a first spur gear SR1 and a second spur gear SR2 composed. The first spur gear SR1 is part of the wheelset RS there rotatably connected, where in the variants of 2 and 4 the rotor R was rotatably connected. The spur gear SR1 then stands with the spur gear SR2 in tooth engagement, which rotatably on an input shaft EW of the electric machine EM is placed inside the electric machine EM the connection to the - not shown here - rotor of the electric machine EM manufactures.

Even with the possibility of modification 7 is the electric machine EM off-set to the respective wheelset RS of the respective transmission G placed. Unlike the previous variant 6 is a connection but not via a spur gear SRS , but via a traction mechanism drive ZT performed. This traction drive ZT can be configured as a belt or chain drive. On the side of the wheelset RS is the traction drive ZT then tied at the point where at the gears G from the 2 and 4 in each case a rotationally fixed connection of the rotor R was completed. About the traction mechanism drive ZT This will then be a coupling to an input shaft EW of the electric machine EM made, in turn, within the electric machine EM makes a connection to the rotor of the electric machine.

In case of modification possibility 8th is an integration of the off-axis to the respective wheelset RS placed electric machine EM about a planetary stage PS and a spur gear stage SRS realized. Here is the planetary stage PS the wheelset RS downstream, with the output side of the planetary stage PS then the spur gear SRS is provided, via which the connection to the electric machine EM is made. The planetary stage PS is made up of a ring gear HO , a planetary bridge PT and a sun wheel SO together, the planetary bridge PT at least one planetary gear PR rotatably mounted, which leads both to the sun gear SO as well as the ring gear HO is in meshing.

The present is the planetary bridge PT from the wheelset RS there rotatably connected, where in the gearboxes G from the 2 and 4 in each case a rotationally fixed connection of the rotor R was completed. In contrast, the ring gear HO permanently on the non-rotatable component GG fixed while the sun gear SO rotatably with a first spur gear SR1 the spur gear stage SRS connected is. The first spur gear SR1 then combs with a second spur gear SR2 the spur gear stage SRS , which rotatably on an input shaft EW of the electric machine EM is provided. In this case, the electric machine EM So on the part of the wheelset RS connected via two gear ratios.

Even with the possibility of modification 9 is an integration of the electric machine EM from the wheelset RS about a planetary stage PS and a spur gear stage SRS performed. The Abwandlungsmöglichkeit largely corresponds to the variant 8th , with the difference that at the planetary stage PS now the sun wheel SO on the non-rotatable component GG is set while the ring gear HO rotatably with the first spur gear SR1 the spur gear stage SRS connected is. Specifically, are the ring gear HO and the first spur gear SR1 preferably integrally formed by the ring gear is equipped on an outer periphery with a toothing. Otherwise, the possibility of modification corresponds to 9 otherwise the variant 8th so that reference is made to what has been described.

Further shows 10 Another modification of the transmission G from the 2 and 4 , whereby also here an integration of the electric machine EM via a spur gear SRS and a planetary stage PS performed. Unlike the previous variant 9 follows the wheelset RS but first the spur gear stage SRS while the planetary stage PS in the power flow between spur gear SRS and electric machine EM is provided. The planetary stage PS also includes the elements ring gear again HO , Planetary bridge PT and sun gear SO , where the planetary bridge PT several planet wheels PR1 and PR2 rotatably mounted, each with both the sun gear SO as well as the ring gear HO in mesh.

As in 10 can be seen, is a first spur gear SR1 the spur gear stage SRS from the wheelset RS rotatably connected, wherein this connection is made at the point where at the gears from the 2 and 4 in each case a rotationally fixed connection of the rotor R was completed. The first spur gear SR1 meshes with a second spur gear SR2 the spur gear stage SRS , which rotatably with the planet web PT the planetary stage PS connected is. The ring gear HO is permanently on the non-rotatable component GG fixed while the sun gear SO rotatably on an input shaft EW of the electric machine EM is provided.

Finally shows 11 Another modification of the transmission G from the 2 and 4 , this modification possibility essentially according to the previous variant 10 equivalent. The only difference is that now the sun wheel SO the planetary stage PS permanently on the non-rotatable component GG is set while the ring gear HO the planetary stage PS rotatably with the input shaft EW the electric machine EM connected is. Otherwise, the possibility of modification corresponds to 11 otherwise the variant 10 so that reference is made to what has been described.

By means of the embodiments according to the invention, a transmission with a compact design and with good efficiency can be realized.

LIST OF REFERENCE NUMBERS

G

transmission

RS

wheelset

GG

Non-rotating 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

K1

First switching element

K2

Second switching element

K3

Third switching element

K4

Fourth switching element

K5

Fifth switching element

K6

Sixth switching element

SP1

Switching element pair

SP2

Switching element pair

SP3

Switching element pair

1.1

First course

1.2

First course

1.3

First course

2.1

Second gear

2.2

Second gear

2.3

Second gear

3

Third gear

4.1

Fourth gear

4.2

Fourth gear

4.3

Fourth gear

4.4

Fourth gear

E1

first course

E2

second gear

LV1

drive shaft

Level 1-A

junction

GW2

output shaft

GW2-A

junction

AT

connecting shaft

EM

electric machine

S

stator

R

rotor

SRS

spur gear

SR1

spur gear

SR2

spur gear

PS

planetary stage

HO

ring gear

PT

planet spider

PR

planet

PR1

planet

PR2

planet

SO

sun

ZT

traction drive

VKM

Internal combustion engine

TS

torsional vibration damper

AG

differential gear

DW

drive wheels

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been 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.

Cited patent literature

• DE 102013013947 A1 [0003]

Claims (14)

Transmission (G) for a motor vehicle, comprising an electric machine (EM), a drive shaft (GW1), an output shaft (GW2), and a first planetary gear set (P1) and a second planetary gear set (P2), the planetary gear sets (P1, P2) each comprise a plurality of elements (E11, E21, E31, E12, E22, E32), and wherein a first (K1), a second (K2), a third (K3), a fourth (K4) and a fifth switching element (K5) are provided, characterized in that - the drive shaft (GW1) rotatably connected to the first element (E12) of the second planetary gear set (P2) and via the first switching element (K1) rotationally fixed to the second element (E21) of the first planetary gear set (P1) can be brought into connection, - that the output shaft (GW2) rotatably connected to the third element (E31) of the first planetary gear set (P1) and by means of the second switching element (K2) rotatably connected to the second element (E22) of the second planetary gear set (P2 ) is connectable, - that a rotor (R) the electric machine (EM) via the third switching element (K3) to the drive shaft (GW1) and by means of the fourth switching element (K4) to the output shaft (GW2) is connectable, - that the second element (E21) of the first planetary gear set (P1) and the second element (E22) of the second planetary gear set (P2) are rotatably connected to each other via the fifth switching element (K5), and in that the first element (E11) of the first planetary gear set (P1) and the third element (E32) of the second one Planetary gear set (P2) are fixed. Transmission (G) to Claim 1 , characterized in that by selective pairwise closing of the five switching elements (K1, K2, K3, K4, K5) a first gear between the drive shaft (GW1) and output shaft (GW2) - in a first variant (1.1) by operating the second K2) and the fourth switching element (K4), - and in a second variant (1.2) by closing the second (K2) and the third switching element (K3), a second gear between the drive shaft (GW1) and output shaft (GW2) - in one first variant (2.1) by actuating the fourth (K4) and the fifth switching element (K5), - and in a second variant (2.2) by closing the third (K3) and the fifth switching element (K5), a third gear (3) between the drive shaft (GW1) and output shaft (GW2) by actuating the third (K3) and the fourth switching element (K4), and a fourth gear between the drive shaft (GW1) and output shaft (GW2) - in a first variant (4.1) by closing the first (K1) and the fourth Scha Ltelements (K4), - and in a second variant (4.2) by closing the first (K1) and the third switching element (K3) results. Transmission (G) to Claim 1 or 2 , characterized in that a first speed (E1) between the rotor (R) of the electric machine (EM) and the output shaft (GW2) results by closing the fourth switching element (K4). Transmission (G) according to one of the preceding claims, characterized in that exactly one electric machine (EM) is provided, which is arranged to drive the output shaft (GW2). Transmission (G) according to one of the preceding claims, characterized in that the rotor (R) of the electric machine (EM) also via a sixth switching element (K6) with the second element (E21) of the first planetary gear set (P1) is connectable. Transmission (G) to Claim 5 , characterized in that - the first gear between the drive shaft (GW1) and the output shaft (GW2) additionally in a third variant (1.3) by closing the second (K2) and the sixth switching element (K6), - the second gear between the drive shaft ( GW1) and output shaft (GW2) in a third variant (2.3) by operating the fifth (K5) and the sixth switching element (K6), - the fourth gear between the drive shaft (GW1) and output shaft (GW2) in a third variant (4.3) by actuating the first (K1) and the sixth switching element (K6) and in a fourth variant (4.4) by closing the third (K3) and the sixth switching element (K6). Transmission (G) to Claim 5 or 6 , characterized in that a second gear (E2) between the rotor (R) of the electric machine (EM) and the output shaft (GW2) results by closing the sixth switching element (K6). Transmission (G) according to one of Claims 1 to 3 , characterized in that a second electric machine is provided, whose rotor is permanently connected to the drive shaft (GW1). Transmission (G) according to one of the preceding claims, characterized in that one or more of the switching elements (K1, K2, K3, K4, K5, K1, K2, K3, K4, K5, K6) are each realized as a form-locking switching element. Transmission (G) according to one of the preceding claims, characterized in that at least one of the planetary gear sets (P1) is present as a minus planetary gear set, wherein it is at the respective first element (E11) of the respective planetary gear set (P1) about a respective sun gear at the respective second element (E21) of the respective planetary gear set (P1) about a respective planet web and at the respective third element (E31) of the respective planetary gear set (P1) a respective ring gear is. Transmission (G) according to one of the preceding claims, characterized in that at least one of the planetary gear sets (P2) is present as a plus-planetary gear, wherein it is the respective first element (E12) of the respective planetary gear set (P2) to a respective sun gear, at the respective second element (E22) of the respective planetary gear set (P2) is a respective ring gear and the respective third element (E32) of the respective planetary gear set (P2) is a respective planet gear. Transmission (G) according to one of the preceding claims, characterized in that at least two switching elements (K1, K3, K2, K5, K4, K6) are each combined into one switching element pair (SP1, SP2, SP3), to which one actuating element is assigned in which one switching element (K1; K2; K4) as well as the other switching element (K3; K5; K6) of the respective switching element pair (SP1; SP2; SP3) can be actuated via the respective one actuating element from a respective neutral position. Motor vehicle drive train for a hybrid vehicle, comprising a transmission (G) after one or more of the Claims 1 to 12 , Method for operating a transmission (G) according to one of Claims 1 to 12 , characterized in that only a third switching element (K3) is closed to represent a charging operation or a start operation.

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