DE102011083700A1 - Gearbox for motor vehicle, has switching units that are associated with respective gear stages that are arranged between hollow gear shaft and output shaft - Google Patents

Abstract

The gearbox has a transmission main shaft (1) that is coupled with a hollow gear shaft (2). A drive shaft (3) is connected with hollow gear shaft. An output shaft (6) is connected to transmission main shaft via a switch unit (S2). A counter shaft (7) is arranged parallel to transmission main shaft, hollow transmission shaft and output shaft, and is provided with a reduction gear (8) and a hollow shaft. The switching units (S3-S7) are associated with respective gear stages (11-15) that are arranged between hollow gear shaft and output shaft.

Description

The invention relates to a motor vehicle transmission, comprising two partial transmissions, which have coaxial with each other arranged input shafts and each alternately by connecting the respective associated input shaft with a drive in a power flow to an output are einbindbar, wherein the input shaft of the first subtransmission as the transmission central shaft and the input shaft of second partial transmission is designed as a hollow gear shaft, wherein the output of both partial transmissions formed by a coaxial with the input shafts output shaft and parallel to the input shafts and the output shaft is provided a countershaft, and wherein a transmitted from the drive to the output rotational movement with one of several discrete ratios can be translated, which in each case by guiding the power flow over the countershaft via at least two spur gears and by operating at least one associated switching device with change between the T. can be displayed power-shiftable.

Such motor vehicle transmissions are designed, inter alia, as so-called dual-clutch transmissions in which the input shafts of the two partial transmissions can be connected via a respective load switching element with a drive, wherein the two load switching elements are then combined in a double clutch. The representable on such a motor vehicle transmission gears are alternately divided between the two partial transmissions, so that the one partial transmission, the odd gears and the other partial transmission represents the even gears. Usually, the individual gears are defined by one or more spur gears, each with discrete ratios, these spur gears then being selectively engageable by associated shifting devices into the power flow so that a corresponding gear ratio between the engine and the output of the automotive transmission is displayed. By alternately splitting the gears on the two partial transmissions, it is possible when driving in a gearbox associated with a gear in the other sub-transmission by appropriate actuation of the switching devices already select a subsequent gear, with a final change in the subsequent gear by Opening the power shift element of a sub-transmission and shortly thereafter following closing of the load switching element of the other sub-transmission is feasible. As a result, the gears of the motor vehicle transmission can be switched under load, which improves an acceleration capacity of the motor vehicle due to the almost traction interruption-free gear change and allows more comfortable switching operations. Among other things, dual-clutch transmissions are in this case also carried out with coaxial drive and output, as well as a countershaft parallel thereto, so that a compact design can be realized in the radial direction. Furthermore, embodiments of dual-clutch transmissions are known in which the individual gears of the transmission are represented by guiding the power flow over a plurality of spur gears, so that compared to conventional transmissions using fewer spur gears results in a correspondingly large number of gears.

From the DE 10 2006 054 281 A1 goes out such a motor vehicle transmission, which is designed as a double-clutch transmission and comprises two partial transmission with coaxially arranged input shafts. By connecting the respective associated input shaft via a respective load switching element, the two partial transmissions can each be alternately incorporated into a power flow from a drive to an output, wherein the input shaft of the first sub-transmission is designed as a transmission central shaft and the input shaft of the second sub-transmission as a hollow shaft transmission. Coaxially to the two input shafts an output shaft of both partial transmission is provided, wherein a rotational movement of the drive with one of several discrete ratios to the output is translatable by the power flow is performed via a parallel to the input shafts and the output shaft provided countershaft. In this case, at least two spur gears, each with a discrete ratio by actuation of associated switching devices are switched into the power flow, wherein the combination of the actuation of the switching devices and the corresponding leadership of the power flow via the associated spur gears, the plurality of gear ratios can be displayed. In addition, however, a direct transmission of the rotational movement of the transmission central shaft to the output shaft by actuation of an intermediate switching device is possible.

Based on the above-described prior art, it is now the object of the present invention to provide a motor vehicle transmission available, in which using as few spur gears and switching devices a large number of powershift gear ratios can be displayed.

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.

According to the invention, a motor vehicle transmission comprises two partial transmissions, which have coaxial with each other arranged input shafts and can be alternately connected by connecting the respective associated input shaft with a drive in a power flow to an output. Here, the input shaft of the first sub-transmission is designed as a transmission central shaft and the input shaft of the second sub-transmission as a hollow shaft transmission. An output of the motor vehicle transmission is formed by a coaxial with the input shafts output shaft, wherein a countershaft is provided parallel to the input shafts and the output shaft. A transmitted from the drive to the output rotational movement can now be translated with one of several discrete gear ratios, which are each shown by switching the power flow on the countershaft on at least two spur gears and by operating at least one associated switching device under change between the partial transmissions.

For the purposes of the invention, the switching devices are preferably designed as synchronizers, via which a positive coupling between two transmission elements, such as a gear shaft and a rotatably mounted idler gear of a spur gear or two gear shafts, is produced by reducing prevailing speed differences. Alternatively, however, in principle, an embodiment of the switching devices as a form-locking switching devices, for example as jaw clutches, or as non-positive switching devices, such as multi-plate clutches, conceivable.

The invention now includes the technical teaching that the transmission central shaft is connected via a first spur gear with a hollow shaft of the intermediate gear, which can be rotatably coupled by actuation of a first switching device with a coaxially extending solid shaft of the intermediate gear. In addition, the transmission central shaft by means of driving a second switching device is directly connected to the output shaft. Furthermore, at least one further spur gear stage is provided between the output shaft or the transmission central shaft on the one hand and the solid shaft or the hollow shaft on the other hand.

By means of the inventive design of a motor vehicle transmission, it is possible to represent a large number of powershift gears with a small number of spur gears and shifting devices. Because of the various connection possibilities between the input shafts, the countershaft and the output shaft, and thus each associated either guiding the power flow on the countershaft or the direct transmission to the output shaft can with the existing spur gear and a combination of the operation of associated switching devices a large Number of gears to be realized. In this case, the countershaft is formed only by a hollow shaft and a solid shaft, so that the motor vehicle transmission according to the invention makes do with a small number of waves when displaying the powershift gears. Finally, a compact construction in the radial direction is realized by the coaxial arrangement of drive and output, as well as by the only one, parallel countershaft.

According to an advantageous embodiment of the invention, the hollow shaft of the intermediate gear can be connected by actuation of a third switching device via a second spur gear with the output shaft. Further, transmission hollow shaft via a third spur gear by driving a fourth switching device and a fourth spur gear by pressing a fifth switching device can be coupled respectively to the solid shaft, which in turn via a fifth spur gear by driving a sixth switching device and a reverse gear by pressing a seventh switching device each with the output shaft can be connected. By providing the further spur gear stages, the number of representable gears can be correspondingly increased, in which case a maximum of seven power-shiftable forward gears and three reverse gears can be represented by the above-described arrangement of the spur gear stages.

In the case of an embodiment of a motor vehicle transmission according to the variant described above, a first forward gear results by connecting the transmission hollow shaft of the second partial transmission to the drive, and by actuating the first, third and fourth switching device, whereas a second forward gear by coupling the transmission central shaft of the first Partial gear with the drive and driving the third switching device can be displayed. Further, a third forward speed is switched by the transmission hollow shaft is in turn connected to the drive and the fourth and the sixth switching means are actuated. A following, fourth forward gear results, however, by coupling the transmission central shaft to the drive and operating the first, and the sixth switching device, while a fifth forward gear by connecting the hollow shaft gear to the drive, as well as a control of the fifth and the sixth switching device can be displayed. Finally, a rotational movement of the drive with a transmission ratio of a sixth forward gear is translated to the output by the transmission central shaft coupled to the drive and a drive of the second switching device is made. Advantageously, can thus be by the above-described control of the switching devices, as well as the alternate connection of the transmission central shaft and the transmission hollow shaft to the drive realize a total of six powershift forward gears, wherein in the sixth forward gear while a direct drive from the transmission central shaft takes place on the output shaft.

Alternatively, a first forward gear can be displayed by connecting the transmission central shaft of the first part of the transmission to the drive, and operating the third switching device. Another, second forward speed is obtained by coupling the transmission hollow shaft of the second partial transmission with the drive, and operating the fourth and the sixth switching device, while a third forward gear by connecting the transmission central shaft to the drive, as well as a control of the first and the sixth switching device is switched , Another fourth forward speed following this is illustrated by coupling the transmission hollow shaft to the drive and actuating the fifth and sixth shifters, a fifth forward speed is switchable by connecting the transmission central shaft to the drive and operating the second shifter. Finally, there is a sixth forward gear by coupling the hollow gear shaft with the drive, as well as operating the first, the second and the fifth switching device. Also in this case, it is thus possible to represent a total of six powershift forward gears through the total of six spur gear and the seven switching devices, the fifth forward gear thereby represents a direct drive from the transmission central shaft to the output shaft and is designed by the sixth forward speed, a smooth transition.

In the context of a further alternative control of the switching devices results in a first forward gear by connecting the transmission central shaft of the first gear to the drive, as well as operating the third switching device, whereas a second forward gear by coupling the hollow shaft of the second gear with the drive and driving the fifth, and the sixth switching device can be displayed. Another, third forward gear is connected by connecting the transmission central shaft to the drive, as well as operating the first and the sixth switching device, a subsequent fourth forward gear by coupling the hollow gear shaft with the drive, and driving the fourth and the sixth switching device. Finally, a fifth forward speed results by connecting the transmission central shaft to the drive and actuating the second shift device, while a sixth forward speed is represented by coupling the transmission hollow shaft to the drive, as well as actuating the first, the second and the fourth shift device. Consequently, six forward gears can also be represented by the above-described control of the individual switching devices. By alternately connecting the two input shafts with the drive of the motor vehicle transmission, the six forward gears can be switched under load.

Further alternatively, a first forward gear results by connecting the transmission central shaft of the first partial transmission with the drive, and operating the first and the sixth switching device, while a second forward gear by coupling the hollow shaft of the second gearbox with the drive and driving the fourth, and the sixth switching device is switched. A subsequent third forward gear is then represented by connecting the transmission central shaft to the drive, and pressing the third switching device, another, fourth forward gear by coupling the hollow gear shaft with the drive, as well as driving the fifth and the sixth switching device. Furthermore, there is a fifth forward speed by coupling the transmission central shaft to the drive and actuation of the second switching device, whereas a sixth forward speed is switched by connecting the hollow gear shaft with the drive, and a drive of the first, the second and the fourth switching device. By means of the above-described control of the individual switching devices, six forward gears can thus again be represented by the total of six spur gear stages and the seven shifting devices, with six power-shiftable forward gears likewise arising here again.

As part of a further alternative control of the switching devices then results in a first forward gear by connecting the transmission central shaft of the first gear to the drive, and operating the first and the sixth switching device, whereas a second forward gear by coupling the hollow shaft of the second gearbox with the drive and driving the fifth, and the sixth switching device can be displayed. A subsequent third forward gear is then connected by connecting the transmission central shaft to the drive and actuating the third shift device, another fourth forward gear by coupling the transmission hollow shaft to the drive and driving the fourth, as well as the sixth switching device. Furthermore, there is a fifth forward gear by coupling the transmission central shaft with the drive, and actuation of the second switching device, whereas a sixth forward speed is represented by connecting the hollow shaft gear to the drive, and a drive of the first, the second and the fifth switching device. By means of the above-described control of the individual switching devices, as well as the mutual coupling of the two Input shafts with the drive can be switched all six forward gears under load.

Alternatively, a first forward gear by connecting the hollow gear shaft of the second partial transmission to the drive, and operating the first, the third and the fourth switching device can be displayed. Another, second forward speed is obtained by coupling the transmission central shaft of the first sub-transmission with the drive and actuating the third switching device, while a third forward gear is connected by connecting the hollow gear shaft to the drive, and a drive of the fourth and the sixth switching device. Another fourth forward speed following this is illustrated by coupling the transmission central shaft to the drive and actuating the first and sixth shifters, and a fifth forward speed is switchable by connecting the transmission hollow shaft to the drive and actuating the fifth and sixth shifters. Finally, there is a sixth forward gear by coupling the transmission central shaft with the drive, and operating the second switching device, whereas a last, seventh forward gear by connecting the hollow shaft gear to the drive, and driving the first, the second and the fifth switching device is displayed. By means of the aforementioned actuation of the individual switching devices, it is thus possible to represent a total of seven powershiftable forward gears through the total of six spur gear stages and the seven shifting devices. In this case, the sixth forward gear is a direct drive from the transmission central shaft to the output shaft, while by the seventh forward gear a smooth gear is configured.

Further alternatively, a first forward gear results by connecting the transmission hollow shaft of the second sub-transmission to the drive, and actuating the first, the third and the fifth shift device, while a second forward gear by coupling the transmission central shaft of the first sub-transmission to the drive and driving the third switching device connected becomes. A subsequent third forward gear is then represented by connecting the hollow gear shaft with the drive, and operating the fifth and the sixth switching device, another, fourth forward gear by coupling the transmission central shaft to the drive, and driving the first and the sixth switching device. Furthermore, there is a fifth forward gear by coupling the hollow gear shaft with the drive and actuation of the fourth, and the sixth switching device, whereas a sixth forward gear is connected by connecting the transmission central shaft to the drive, and a drive of the second switching device. Finally, a last, seventh forward gear by coupling the hollow gear shaft with the drive, as well as operating the first, the second and the fourth switching device can be displayed. By means of the above-described control of the individual switching devices, seven forward gears can thus again be represented by the total of six spur gear stages and the seven shifting devices, whereby seven power-shiftable forward gears likewise likewise result.

In all of the aforementioned variants of a control of the switching devices results in addition, a first reverse by connecting the transmission hollow shaft of the second gear to the drive, and operating the fourth and the seventh switching device, while a second reverse by coupling the transmission hollow shaft to the drive, as well as control the fifth and the seventh switching device can be displayed. Finally, a third reverse gear is connected by connecting the transmission central shaft to the drive and operating the first, and the seventh switching device. Thus arise in the individual transmission variants in each case a total of three reverse gears, with switching according to the above order only a zugkraftunterbrechungsfreier change between the second and the third reverse gear is possible, since the first and the second reverse gear are both represented by coupling the hollow gear shaft to the drive , However, the reverse gears may also be arranged in a different order than described above, for example, first reverse, third reverse, and second reverse, so that power shiftability can be exhibited. In the individual arrangement possibilities, however, the transmission ratio defined in each individual reverse gear must be taken into account.

In a further development of the invention, the second and the third switching device are combined in a switching package, which is arranged on the output shaft. This has the advantage that the second and the third switching device can thus each be alternately actuated via a common actuator, which simplifies the construction of a transmission control of the motor vehicle transmission according to the invention accordingly. At the same time, two switching devices are combined, which are not actuated at the same time due to the connection then produced during actuation, so that the overall number of speeds that can be represented is not impaired by the combination.

Alternatively or in addition to the variant described above, the fourth and the fifth switching device are formed by a common switching package, which on the hollow shaft gear or on the solid shaft of the intermediate gear is placed. This also makes it possible, in turn, to actuate two switching devices alternately via a common actuator and thereby to design a control of the motor vehicle transmission according to the invention with a few actuators. Furthermore, the collapsing of the two switching devices does not reduce the number of switchable gears, since a translation of a rotational movement with a discrete gear ratio of the third spur gear from the hollow gear shaft is shown on the solid shaft via the fourth switching device, while upon actuation of the fifth switching device, a translation with a deviating Translation ratio takes place. Accordingly, a simultaneous actuation of the two switching devices is not carried out, so that a summarizing is not a problem. The placement of the shift package on the transmission hollow shaft has the advantage that the applied during the switching operation switching forces of the switching package can be reduced and occurring loads of the switching devices can be reduced accordingly, so that the fourth and the fifth switching device can be made smaller, if necessary. However, the possibility of this arrangement is dependent on the discrete ratios of the third and the fourth spur gear, since at high ratios too large differential speeds would be reduced via the switching devices. In the second-mentioned case, in which the shift package is arranged on the solid shaft of the countershaft, a moment of inertia can be reduced to the transmission hollow shaft.

In a further development of this embodiment of the invention, the third spur gear stage is provided on the drive side or output side to the switching package, which forms the fourth and the fifth switching device. The fourth spur gear is then arranged according to the output side or drive side to the switching package. For the purposes of the invention, a "drive-side" placement relative to an element generally refers to an arrangement on a side of the respective element facing the drive, while a "drive-side" arrangement generally refers to a placement on a side of the element facing the drive , In the present case, therefore, the third spur gear stage with respect to the switching package, which summarizes the fourth switching device and the fifth switching device, either provided by the drive or the output, while the fourth spur gear is arranged exactly the reverse either on the part of the output or the drive.

Next alternatively or in addition to the two variants described above, the sixth and the seventh switching device are combined in a switching package, which is arranged on the output shaft or on the solid shaft of the intermediate gear. Accordingly, the structure of a control of the motor vehicle transmission can also be simplified in this area by the two switching devices can in turn be operated alternately via a common actuator. Since the sixth switching device on actuation of the fifth spur gear and the seventh switching device switches the reverse gear in the power flow, which each causes a translation of a rotational movement from the solid shaft to the output shaft with a discrete gear ratio, a simultaneous actuation of the two switching devices is excluded. Accordingly, the collapsing also does not reduce the number of switchable gears. The placement of the switching package on the solid shaft results in a reduction of the switching forces to be applied upon actuation of the sixth and the seventh switching device, so that they may be designed smaller and thus the switching package can be made more compact. The placement of the shift package on the solid shaft has the further advantage that idle when the vehicle is stationary, the idler gears of the fifth spur gear and the reverse gear not rotate and accordingly do not contribute to a noise. However, the possibility of this arrangement, in turn, depends on the respective translations defined by the fifth spur gear stage and the reverse gear step, since, if necessary, too high differential rotational speeds are to be dissipated via the shifting devices. By contrast, by placing the switching package on the output shaft, a mass moment of inertia can be reduced to the two input shaft.

In a further development of this embodiment, the fifth spur gear stage is placed on the drive side or output side to the switching package, which summarizes the sixth and the seventh switching device, the reverse gear is then provided according to the output side or drive side to the switching package. The fifth spur gear is thus arranged with respect to the sixth and the seventh switching device forming switching package on the side of the drive or the output, whereas the reverse gear is then placed exactly opposite thereto from the output or the drive.

According to a further advantageous embodiment of the invention meshes depending on a gear of the third, the fourth and / or the fifth spur gear and / or the reverse gear with an associated gear per a shaft, which is connected to an electric machine. As a result, a hybridization of the motor vehicle transmission according to the invention is possible by each driven by a gear and the respective shaft an electric machine and thus electrical energy can be generated or each driving an electric machine to support a drive movement or purely electric driving on the Shaft and thus acting on the respective spur gear.

The coupling of each electric machine via the respective one shaft and the associated gear with the second, the third and / or the fifth spur gear and / or the reverse gear in this case has the particular advantage that at these spur gear each due to the inventive placement of the switching devices Both a connection to the drive and a connection to the output can be separated. Thus, when the connection to the drive is interrupted, it is also possible to display purely electric driving without causing drag losses of a double clutch provided on the drive side. Due to the possibility of decoupling on the output side, when the vehicle is at a standstill, charging of an electrical accumulator can be represented by the electric machine being connected to the drive unit of the motor vehicle transmission via the respective spur gear stage, while no rotational movement is transmitted to the output. Preferably, the one gear in each case meshes with a provided on the counter gear of the respective spur gear. In addition, it is possible according to the invention to provide a total of only one electric machine in the region of one of the aforementioned spur gear stages or even a plurality of electric machines, which are then assigned in each case in each case one of the spur gear stages.

Apart from that, however, it is also conceivable within the scope of the invention to provide at least one electric machine in the range of one of the shafts of the transmission or directly to each a fixed gear of the spur gears to arrange directly to each one idler gear of the spur gear or to an additional fixed wheel. At the respective positions is then recuperated by the electric machine either energy or supports a rotational movement or a purely electric driving, d. H. an operation of the motor vehicle transmission via the at least one electric machine allows.

According to the invention, the first switching device is furthermore arranged either on the drive side or on the output side of the hollow shaft of the intermediate gear. In both cases, the first switching device can be placed axially adjacent to the switching packets, so that there is sufficient space for the individual switching devices in the radial direction, as well as for the respective associated actuators. In the case of the drive-side arrangement, the first switching device is placed in the axial direction between the first spur gear and the drive, while it is in the output-side arrangement in the axial direction between the second spur and the output.

In a further development of the invention, a connection of the input shafts of the two partial transmissions to the drive is carried out via respective assigned load switching elements, which are combined in a double clutch. A double clutch is configured in particular as a wet-running double clutch, but can also be designed to run dry at low torques to be transmitted. Apart from two load switching elements but also a single coupling the input shaft to the drive load switching element and a positive coupling between the input shafts may be provided, wherein a drive torque during the transition from one to the other partial transmission is represented by an electric machine, which during the circuit and integration of the other sub-transmission drives and is connected to the other input shaft. Here, by providing a planetary gear but also a common provision of the drive torque by an electric machine and the drive unit of the vehicle conceivable. Furthermore, a double switching element can also be provided in the region of the input shafts, by means of which it is possible to switch over between the two aforementioned variants.

The invention is not limited to the specified combination of the features of the main claim or the dependent claims. It also results in ways to combine individual features, even if they emerge from the claims, the following description of embodiments 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.

Further, advantageous embodiments of the invention will become apparent from the following description of preferred embodiments of the invention, which refers to the Fig. Illustrated in the drawings. It shows:

1 a schematic representation of a motor vehicle transmission according to the invention according to a first preferred embodiment of the invention;

2 a schematic representation of a second preferred embodiment of a motor vehicle transmission according to the invention;

3 a schematic view of a motor vehicle transmission according to the invention according to a third preferred embodiment of the invention;

4 a schematic representation of a fourth preferred embodiment of a motor vehicle transmission according to the invention;

5 an exemplary circuit diagram of a motor vehicle transmission according to the invention according to the 1 to 4 ;

6 a further exemplary circuit diagram of a motor vehicle transmission according to the invention according to the 1 to 4 ;

7 a further exemplary circuit diagram of a motor vehicle transmission according to the invention according to the 1 to 4 ;

8th a further exemplary circuit diagram of a motor vehicle transmission according to the invention according to the 1 to 4 ;

9 a further exemplary circuit diagram of a motor vehicle transmission according to the invention according to the 1 to 4 ;

10 a further exemplary circuit diagram of a motor vehicle transmission according to the invention according to the 1 to 4 ; and

11 a further exemplary circuit diagram of a motor vehicle transmission according to the invention according to the 1 to 4 ,

Out 1 is a schematic representation of a motor vehicle transmission according to the invention according to a first preferred embodiment of the invention can be seen, which is in this motor vehicle transmission in particular is a transmission of a commercial vehicle. The motor vehicle transmission in this case comprises two partial transmissions, to each of which an input shaft is assigned. In this case, an input shaft of the first partial transmission as the transmission central shaft 1 executed, to which the transmission hollow shaft 2 executed input shaft of the second partial transmission is coaxial. The two partial transmissions can now alternately into a power flow of a drive 3 the motor vehicle transmission, which is in communication with a drive unit of the motor vehicle, to an output 4 be integrated by either the transmission central shaft 1 of the first part of the transmission via an associated load switching element K1 or the transmission hollow shaft of the second partial transmission via an associated load switching element K2 to the drive 3 is coupled. The two load switching elements K1 and K2 are in a double clutch 5 summarized, which is preferably a wet-running double clutch. The downforce 4 is through an output shaft 6 formed coaxially with the transmission central shaft 1 and the transmission hollow shaft 2 runs. In addition, it is still parallel to the transmission central shaft 1 , the transmission hollow shaft 2 , and the output shaft 6 a counterfeit 7 provided, which is a solid shaft 8th and a hollow shaft 9 composed, wherein the hollow shaft 9 coaxial with the solid shaft 8th runs.

A rotary motion of the drive 3 can now be translated via one of the two partial transmission to the output shaft 6 and thus on the downforce 4 be transmitted by the power flow from the transmission central shaft 1 or the transmission hollow shaft 2 about the counter 7 to be led. The transmission central shaft 1 stands for this purpose via a first spur gear 10 permanently with the hollow shaft 9 of the additional gear 7 in conjunction, which with the solid shaft 8th can be rotatably connected via a first switching device S1. In the present case, this switching device S1 is designed as a synchronization, whose - not shown in detail here - sliding sleeve on a - also not shown - actuator targeted from a neutral position in the solid shaft 8th with the hollow shaft 9 positively coupling position can be moved, with this shift known in the art way by synchronizing speed differences between the solid shaft 8th and the hollow shaft 9 be reduced.

As further out 1 As can be seen, the transmission central shaft 1 by actuating a second switching device S2 with the coaxial output shaft 6 be connected so that a rotational movement of the transmission central shaft 1 directly and without translation to the output shaft 6 is transmitted. In this case, this second switching device on the output side of the first spur gear 10 intended. In addition, the hollow shaft carries 9 of the additional gear 7 axially adjacent to the second switching device S2 a fixed gear of a second spur gear 11 whose idler gear is on the output shaft 6 is rotatably mounted and by means of a third switching device S3 rotatably connected to the output shaft 6 can be connected, so that a rotational movement of the hollow shaft 9 with a discrete ratio of the second spur gear 11 on the output shaft 6 is transmitted.

On the full wave 8th are in the axial direction between the double clutch 5 and the first spur gear stage 10 Fixed wheels of a third spur gear 12 and a fourth spur gear stage 13 arranged, each of which is in meshing engagement with a respective idler gear, wherein the idler gears rotatably on the hollow gear shaft 2 are stored. Here, the idler gear of the third spur gear 12 by actuating a fourth switching device S4 on the transmission hollow shaft 2 be set so that a rotational movement of the hollow shaft transmission 2 with a discrete translation of the third spur gear 12 to the full wave 8th of the additional gear 7 is transmitted. Likewise, the idler gear of the fourth spur gear can also 13 by driving an associated, fifth switching device S5 rotationally fixed to the transmission hollow shaft 2 be connected, in which case a rotational movement of the hollow gear shaft 2 with a discrete translation of the fourth spur gear 13 with a rotary motion of the solid shaft 8th of the additional gear 7 is coupled.

As further out 1 it can be seen wearing the solid shaft 8th of the additional gear 7 on one of the downforce 4 facing side of the first spur gear 10 also each a fixed gear of a fifth spur gear 14 and a reverse gear 15 , The fixed wheel of the fifth spur gear stage 14 meshes with one on the output shaft 6 rotatably mounted idler gear, which via a sixth switching device S6 on the output shaft 6 can be fixed, so that a rotary motion of the solid shaft 8th with a discrete translation of the fifth spur gear 14 with a rotational movement of the output shaft 6 is coupled.

In the same way, the idler gear of the axially adjacent reverse gear is 15 with the output shaft 6 connectable via an associated, seventh switching device S7. However, this idler gear is the reverse gear 15 about one on a parallel intermediate shaft 16 rotatably mounted idler with, on the solid shaft 8th rotatably mounted fixed gear in conjunction. When coupling the idler gear of the reverse gear 15 with the output shaft 6 Accordingly, a rotary movement of the solid shaft via the seventh switching device S7 8th with a discrete total ratio, which consists of the individual translations of fixed gear and intermediate gear, as well as idler gear and idler gear of the reverse gear 15 composed, on the output shaft 6 transfer. This is the same direction of rotation of solid shaft 8th and output shaft 6 caused, so that the output shaft 6 in the end, an opposite rotational movement to the transmission central shaft 1 and also the transmission hollow shaft 2 performs. As a result, a reverse drive of the respective motor vehicle can be represented.

In the present case, the switching devices S1 to S7 are each designed as synchronizers. In the case of the switching devices S3 to S7, when actuated in each case an associated idler gear of the respective spur gear 11 to 15 in a manner known to those skilled in the art with prior reduction of speed differences with the respective shaft 1 respectively. 2 respectively. 6 coupled. On actuation of the switching devices S1 and S2, in contrast, two shafts, in each case, are connected to one another in a form-fitting manner as from the attainment of a speed equality, in the case of the switching device S1, the solid shaft 8th and the hollow shaft 9 , as well as with respect to the switching device S2, the transmission central shaft 1 and the output shaft 6 ,

As well as out 1 can be seen, are now the second switching device S2 and the third switching device S3 to a first switching packet SP1, the fourth switching device S4 and the fifth switching device S5 to a second switching packet SP2, and the sixth switching device S6 and the seventh switching device S7 to a third switching packet SP3 summarized. In this case, the first shift pack SP1 and the third shift pack SP3 are each on the output shaft 6 provided while the second shift packet SP2 on the hollow shaft transmission 2 are placed. In addition, the switching packets SP1 to SP3 are each configured as double synchronizers, in which the respective associated switching devices S2 and S3 or S4 and S5 or S6 and S7 each have a common shift sleeve, which selectively from a respective neutral position via a respective associated actuator either in an operating position of the respective one switching device S2 or S4 or S6 or in an operating position of the respective other switching device S3 or S5 or S7 can be moved. By contrast, the first switching device S1 designed as a single synchronization is on the drive side to the hollow shaft 9 on the full wave 8th of the additional gear 7 arranged and placed lying in the axial direction between the second switching packet SP2 and the first switching packet SP1. In addition, switching devices S2 and S3 or S4 and S5 or S6 and S7 are summarized in the switching packets SP1 to SP3, which would lead to an over-determination of the wheelset and thus to a blocking of the transmission with simultaneous actuation. Thus, the only alternately possible in a switching package operation causes no reduction in the number of representable gears.

Another special feature is the one on the hollow shaft 9 arranged fixed wheel of the third spur gear 12 a gear 17 , rotatably on a shaft 18 is arranged, this wave 18 with an electric machine 19 communicates. Accordingly, a rotary motion of the solid shaft 8th with a rotary motion of the shaft 18 by the tooth engagement of the gear 17 with the fixed gear of the third spur gear 12 and a translation defined thereby. The electric machine 19 can act either as a generator and when driving on the shaft 18 electrical energy in a - not shown here - feed electrical memory, or operated as an electric motor, which when energized driving the shaft 18 acts. As a result, the electric machine 19 either over the full wave 8th be driven or the solid shaft 8th drive and this then either a rotary motion of the solid shaft 8th support or initiate a corresponding drive movement.

The connection of the electric machine 19 over the gear 17 to the third spur gear 12 has the advantage that the electric machine 19 thus on the switching devices S1, S4 and S5 on the one hand of the double clutch 5 and on the other via the switching devices S6 and S7 from the output 4 can be disconnected. In the latter case, an operation of the electric machine 19 over the third spur gear 12 without transmitting a rotary motion to the output 4 allows, so the electric machine 19 can be operated even when the vehicle is to charge an electrical storage. In the other case, over the electric machine 19 a purely electric driving are represented by these on the first switching device S1, the fourth switching device S4 and the fifth switching device S5 of the double clutch 5 and therefore also from the drive 3 decoupled, due to the decoupling of the double clutch 5 Towing losses of the coupling 5 can be prevented. Alternatively, the electric machine 19 but also on the fourth spur gear 13 , the fifth spur gear 14 or at the reverse gear 15 be connected, as well as the corresponding Abkoppelungsmöglichkeiten are given.

Out 2 shows a second preferred embodiment of a motor vehicle transmission according to the invention. In contrast to the embodiment according to 1 are the fixed wheels of the third spur gear 12 and the fourth spur gear stage 13 in this case on the transmission hollow shaft 2 and the fixed gears of the fifth spur gear 14 and the reverse gear 15 on the output shaft 6 placed so that loose wheels of the spur gears 12 to 15 on the full wave 8th of the additional gear 7 are rotatably mounted and in each case via the also provided there, associated switching packages SP2 and SP3 rotatably with the solid shaft 8th can be connected. The switching packets SP2 and SP3 are then again composed of the individual switching devices S4 and S5 or S6 and S7. Furthermore, no electric machine is provided in this case, since a decoupling of drive 3 and downforce 4 present in none of the spur gears 12 to 15 given is. Otherwise, the embodiment corresponds to 2 but according to 1 , In the context of the invention, it is also conceivable, only a single switching package SP2 or SP3 on the solid shaft 8th relocate.

Furthermore goes out 3 a third preferred embodiment of a motor vehicle transmission according to the invention. Different from the variant according to 1 is here that the first switching device S1 in this case the output side of the hollow shaft 9 and placed axially between the first switching packet SP1 and the third switching packet SP3. Furthermore, the gear is 17 in this case in meshing with the fixed gear of the fourth spur gear 13 so that the electric machine 19 at the fourth spur gear stage 13 affiliated. Otherwise, the motor vehicle transmission corresponds to 3 according to the variant 1 ,

Out 4 is a further, fourth preferred embodiment of a motor vehicle transmission according to the invention can be seen, this embodiment of the variant according to 1 distinguished in that the third spur gear 12 and the fourth spur gear 13 are reversed in terms of their positioning to the second switching packet SP2. So is the fourth spur gear 13 on one of the drive 3 facing side of the second switching packet SP2 and the third spur gear 12 on one of the downforce 4 placed facing side of the second switching packet SP2. Accordingly, the fourth switching device S4 and the fifth switching device S5 have also changed positions within the second switching packet SP2. In the same way also have the fifth spur gear 14 and the reverse gear 15 their positions with respect to the third switching package SP3 exchanged, so that the fifth spur gear 14 on the output side 4 and the reverse gear 15 from the drive 3 is provided. In this case, the arrangement of the sixth switching device S6 and the seventh switching device S7 within the third switching packet SP3 is then changed. Furthermore, the gear is 17 in this case meshing with the fixed gear of the reverse gear 15 so that the electric machine 19 at the reverse gear 15 affiliated. Otherwise, the motor vehicle transmission corresponds to 3 according to the variant 1 ,

The above-described variants of a motor vehicle transmission according to the 1 to 4 can with regard to an arrangement of the second switching packet SP2 and the third switching packet SP3, with regard to a placement of the spur gear 12 to 15 relative to the second switching packet SP2 and the third switching packet SP3, with respect to the arrangement of the first switching device S1 and finally also with regard to the provision and the arrangement of an electrical machine 19 be combined with each other as desired. This then results in further variants of a motor vehicle transmission according to the invention. It is also conceivable, ever an electric machine 19 at the spur gear stages 12 to 15 to tie.

In 5 Now, an exemplary circuit diagram is shown, which extends through each of the transmission variants according to the 1 to 4 can be realized. In total, six forward gears and three reverse gears can be displayed. Here, each of the gears by operating one or more of the switching devices S1-S7, as well as connecting the transmission central shaft 1 about the Power shift element K1 or the hollow shaft transmission 2 via the load switching element K2 with the drive 3 shown. In the first five gears, the power flow is over the counter gear 8th and two each of the spur gears 10 to 15 guided, allowing a rotational movement of the drive 3 translated slowly to the output shaft 6 and thus on the downforce 4 is transmitted. In sixth gear, however, a rotational movement of the drive 3 rigid on the output shaft 6 and thus transferred directly.

Between the forward gears also a gear change under load is possible in each case, which is achieved in a manner known to those skilled in that when driving in a corridor and guiding the power flow through one of the two partial transmission in the respective other partial transmission already at the representation a subsequent course stakeholders of the switching devices S1-S7 are preselected and the final gear change then only the load switching element K1 or K2 of a sub-transmission open and immediately thereafter the load switching element K2 or K1 of the other sub-transmission is closed. As a result, a nearly traction-free driving is possible in this area.

In the present case, the first forward gear is now represented by the fact that the load switching element K2 closed and thus the transmission hollow shaft 2 with the drive 3 is connected, and the first switching device S1, the third switching device S3 and the fourth switching device S4 are actuated. To change to the second forward gear then only switching between the load switching elements K1 and K2 must be done by the load switching element K2 is opened and load switching element K1 is closed, in which case after switching the two switching devices S1 and S4 are turned off. In the following third forward gear can then be changed again with a change between the load switching elements K1 and K2, in advance the fourth switching device S4 and the sixth switching device S6 are to be operated and after the change, the third switching device S3 is off. The fourth forward speed is given by the previously made in advance additional operation of the first switching device S1, wherein to change starting from the third forward gear then close the load switching element K1 and the load switching element K2 is to open in advance. Upon further upshifting, the fifth forward speed is obtained by actuating the fifth shift device S5 and the sixth shift device S6, and a subsequent opening of the load shift element K1 and actuation of the load shift element K2. In the sixth forward gear is then through the second switching device S2, the transmission central shaft 1 directly with the output shaft 6 coupled, in this case the load switching element K2 to open when switching from the fifth to the sixth forward gear and the load switching element K1 is to close.

The first reverse gear results, however, by operating the fourth switching device S4 and the seventh switching device S7, and by connecting the hollow gear shaft 2 with the drive 3 via the load switching element K2. The second reverse gear is switched by an additional operation of the fifth switching device S5 to the seventh switching device S7 and switching off the fourth switching device S4, wherein the eventual switching again the transmission hollow shaft 2 with the drive 3 is to be connected by means of the load switching element K2. Accordingly, the load switching element K2 is to be opened, while the fourth switching device S4 is brought into an unactuated state and the fifth switching device S5 is driven, which is associated with an interruption of the pulling force. A change in the following third reverse gear is then possible under load by the load switching element K2 is opened and the load switching element K1 is closed, in advance to operate the first switching device S1 and then the fifth switching device S5 in an unactuated state convict is. In the present case, the representable reverse gears are arranged in such a way that a transition from the first to the second reverse gear can only be displayed with interruption of traction. However, it is conceivable within the scope of the invention, a different order, the feasibility depends on the defined in the individual reverse gear ratios. Thus, for example, an arrangement in the order of first reverse gear, third reverse gear and second reverse gear could be selected, so that would be given by the then take place change between the load switching elements K1 and K2 a load switchability between all reverse gears.

Further, go out 6 another exemplary circuit diagram. Unlike the scheme 5 In this case, in the first four forward gears, a translation into slow is made, while in a fifth forward gear, a direct drive from the transmission central shaft 1 on the output shaft 6 he follows. In a sixth forward gear, however, a translation into fast, so that a smooth transition is configured. Further, the odd gears are each represented by closing the load switching element K1 and the even gears by operating the load switching element K2, the assignment of the gears to the two partial transmissions was thus exchanged. Further different from the scheme 5 In addition, only the third switching device S3 is actuated to switch a first forward gear. Furthermore, a second forward gear is through Driving the fourth switching device S4 and the sixth switching device S6 instead of the third switching device S3 and a third forward speed by operating the first switching device S1 instead of the fourth switching device S4 shown. As another difference to the scheme after 5 For switching a fourth forward gear instead of the first switching device S1, the fifth switching device S5 is actuated, and at a fifth forward gear only the second switching device S2 is activated. Finally, in a sixth forward gear next to the second switching device S2 nor the first switching device S1 and the fifth switching device S5 to operate. Otherwise, the circuit diagram corresponds to 6 but according to 5 ,

In 7 is yet another exemplary circuit diagram of the transmission variants according to the 1 to 4 shown. This corresponds largely to the according 6 in which, as difference in a second forward gear, instead of the fourth shift device S4, the fifth shift device S5 is actuated. Furthermore, in a fourth forward gear instead of the fifth shift device S5, the fourth shift device S4 is to be controlled. Finally, also for shifting a sixth forward gear, the fifth shift device S5 is operated in place of the fourth shift device S4. Incidentally, the circuit diagram corresponds to 7 then according to 6 ,

Further, go out 8th another exemplary circuit diagram. This also largely corresponds to the according 6 , It is different that a first forward gear by pressing the first switching device S1 and the sixth switching device S6 is shown. In addition, only the third switching device S3 is to be controlled in a third forward gear. Finally, to display a sixth forward gear in addition to the first switching device S1 and the second switching device S2 nor the fourth switching device S4 to operate. Otherwise, the wiring diagram is correct 8th with the according to 6 match.

In 9 is yet another exemplary circuit diagram of the transmission variants according to the 1 to 4 shown. This differs from the circuit diagram 6 in that at a first forward gear instead of the third shift device S3, the first shift device S1 and the sixth shift device S6 are to be controlled. Furthermore, for switching a second forward gear instead of the fourth shift device S4, the fifth shift device S5 is to be actuated, and at a third forward gear the third shift device S3 instead of the first shift device S1 and the sixth shift device S6. Finally, there is still a fourth forward gear, in contrast to the scheme according to 6 the fourth switching device S4 instead of the fifth switching device S5 is controlled. Otherwise, the circuit diagram corresponds to 9 according to 6 ,

In 10 is yet another exemplary circuit diagram of the transmission variants according to the 1 to 4 shown. This differs from the circuit diagram 5 to the effect that at a sixth forward gear, in which a direct drive from the transmission central shaft 1 on the output shaft 6 takes place, another seventh forward gear is provided, in which a translation is made quickly and thus a smooth transition is designed. Regarding the off 5 resulting schematics, the variant differs 10 only to the effect that the seventh forward gear is additionally switchable by the load switching element K1 is closed after opening the load switching element K2 and in advance the first switching device S1, and the fifth switching device S5 are operated in addition to the second switching device S2. Otherwise, the wiring diagram is correct 10 with the according to 5 match.

Finally, go out 11 Yet another, exemplary circuit diagram of a motor vehicle transmission according to the invention. Unlike the scheme 10 At a first forward speed and at a third forward speed, the fifth shift device S5 is actuated instead of the fourth shift device S4. Further, with regard to a fifth forward gear and a seventh forward gear, the fourth shift device S4 is to be controlled instead of the fifth shift device S5. Incidentally, the circuit diagram corresponds to 11 then according to 10 ,

In addition to the individual transmission variants according to the 1 to 4 In the context of the invention, synchronizations that are used as switching devices S1 to S7 are, in principle, also conceivable as otherwise form-fitting clutches, for example jaw clutches. In addition, the switching devices S1 to S7 can also be designed as non-positive clutches, preferably as multi-plate clutches. Furthermore, it is according to the invention in addition to the variants of the arrangement of an electric machine shown in the figures 19 also conceivable to provide a plurality of electrical machines, and this possibly also on one or more waves, a fixed gear of the spur gears 10 to 15 , on a loose wheel of the spur gears 10 to 15 or on an additionally provided fixed gear, similar to gear 17 to arrange.

Incidentally, the existing of the two load switching elements K1 and K2 double clutch 5 be replaced by an electric machine, which provides in combination with a single load switching element alone during the circuits for a corresponding support or in combination with the drive unit and an additional planetary gear the characteristic of a dual clutch 5 mimics. Possibly. is in these two variants then provide an additional double switching element through which the two variants can be switched.

By means of the individual embodiments of a motor vehicle transmission according to the invention, it is thus possible to represent a high number of powershift gears when using fewer spur gears and less switching devices. Furthermore, a good hybridisability of the motor vehicle transmission according to the invention is given.

LIST OF REFERENCE NUMBERS

1

Gear central shaft

2

Gearbox hollow shaft

3

drive

4

output

5

Double coupling

6

output shaft

7

countershaft

8th

Solid shaft

9

hollow shaft

10

first spur gear

11

second spur gear

12

third spur gear

13

fourth spur gear

14

fifth spur gear

15

Reverse gear

16

intermediate shaft

17

gear

18

wave

19

Electric machine

K1

Load switching element

K2

Load switching element

S1

first switching device

S2

second switching device

S3

third switching device

S4

fourth switching device

S5

fifth switching device

S6

sixth switching device

S7

seventh switching device

SP1

first switching package

SP2

second switching package

SP3

third switching package

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 102006054281 A1 [0003]

Claims (10)

Motor vehicle transmission, comprising two partial transmissions, which have coaxial with each other arranged input shafts and each alternately by connecting the respective associated input shaft with a drive ( 3 ) into a power flow to an output ( 4 ) are einbindbar, wherein the input shaft of the first sub-transmission as the transmission central shaft ( 1 ) and the input shaft of the second partial transmission as a hollow shaft transmission ( 2 ) is executed, wherein the output ( 4 ) of both partial transmissions by a coaxial with the input shafts placed output shaft ( 6 ) and parallel to the input shafts and the output shaft ( 6 ) a submission ( 7 ), and one of the drive ( 3 ) on the output ( 4 ) transmitted rotational movement with one of a plurality of discrete gear ratios can be translated, which in each case by guiding the flow of force on the countershaft ( 7 ) via at least two spur gears ( 10 to 15 ) and by operation of at least one associated switching device (S3 to S7) can be displayed under load alternately between the partial transmissions, characterized in that the transmission central shaft ( 1 ) via a first spur gear stage ( 10 ) with a hollow shaft ( 9 ) of the counterweight ( 7 ), which by rotation of a first switching device (S1) with a coaxial solid shaft ( 8th ) of the counterweight ( 7 ) is coupled, wherein the transmission central shaft ( 1 ) also by driving a second switching device (S2) directly to the output shaft ( 6 ) is connectable, and that at least one further spur gear ( 11 to 15 ) between the output shaft ( 6 ) or the transmission hollow shaft ( 2 ) on the one hand and the full wave ( 8th ) or the hollow shaft ( 9 ) is provided on the other hand. Motor vehicle transmission according to claim 1, characterized in that the hollow shaft ( 9 ) of the counterweight ( 7 ) via a second spur gear stage ( 11 ) by actuating a third switching device (S3) with the output shaft ( 6 ) is connectable, and that the transmission hollow shaft ( 2 ) via a third spur gear stage ( 12 ) by driving a fourth switching device (S4) and a fourth spur gear ( 13 ) by actuating a fifth switching device (S5) in each case with the solid shaft ( 8th ), which furthermore can be connected via a fifth spur gear stage ( 14 ) by driving a sixth switching device (S6) and via a reverse gear (S6) 15 ) by actuating a seventh switching device (S7) in each case with the output shaft ( 6 ) is connectable. Motor vehicle transmission according to claim 2, characterized in that the second (S2) and the third switching device (S3) in a switching package (SP1) are combined, which on the output shaft ( 6 ) is arranged. Motor vehicle transmission according to claim 2, characterized in that the fourth (S4) and the fifth switching device (S5) by a common switching package (SP2) are formed, which on the transmission hollow shaft ( 2 ) or on the full wave ( 8th ) of the counterweight ( 7 ) is placed. Motor vehicle transmission according to claim 4, characterized in that the third spur gear stage ( 12 ) is provided on the drive side or output side to the switching package (SP2), which forms the fourth (S4) and the fifth switching device (S5), in which case the fourth spur gear stage ( 13 ) is arranged on the output side or drive side to the switching package (SP2). Motor vehicle transmission according to claim 2, characterized in that the sixth (S6) and the seventh switching device (S7) are combined in a switching package (SP3), which on the output shaft ( 6 ) or on the full wave ( 8th ) of the counterweight ( 7 ) is arranged. Motor vehicle transmission according to claim 6, characterized in that the fifth spur gear stage ( 14 ) is placed on the drive side or the output side to the switching package (SP3), which summarizes the sixth (S6) and the seventh switching device (S7), wherein the reverse driving step ( 15 ) is then provided on the output side or drive side to the switching package (SP3). Motor vehicle transmission according to claim 2, characterized in that a respective toothed wheel of the third ( 12 ), the fourth ( 13 ) and / or the fifth ( 14 ) Spur gear stage and / or the reverse gear stage ( 15 ) with an associated gear ( 17 ) one wave each ( 18 ) meshes, which each with an electric machine ( 19 ) connected is. Motor vehicle transmission according to claim 1, characterized in that the first switching device (S1) on the drive side or the output side of the hollow shaft ( 9 ) of the counterweight ( 7 ) is arranged. Motor vehicle transmission according to claim 1, characterized in that the transmission central shaft ( 1 ) and the transmission hollow shaft ( 2 ) in each case via an associated load switching element (K1, K2) to the drive ( 3 ) are connectable, wherein the load switching elements (K1, K2) in a double clutch ( 5 ) are summarized.

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