Transmission for a Motor Vehicle, and Drive Train for a Motor Vehicle

Abstract

A transmission (G) for a motor vehicle includes an input shaft (GW1), an output shaft (GW2), a front-mounted gear set (VRS) with a first planetary gear set (P1) and a second planetary gear set (P2), a main gear set (HRS), an electric machine (EM) with a stator (S) and a rotor (R), and a plurality of shift elements. By selective engagement of three of the shift elements in each case, a plurality of fixed transmission ratios between the input shaft (GW1) and the output shaft (GW2) are shiftable. The two planetary gear sets (P1, P2) of the front-mounted gear set (VRS) include, in addition to the first shaft (Wx1) and the second shaft (Wx2), precisely three further shafts, namely a third shaft (Wx3), a fourth shaft (Wx4), and a fifth shaft (Wx5). A drive train for a motor vehicle may include such a transmission (G).

Claims

1-15. (canceled)

16. A transmission (G) for a motor vehicle, comprising an input shaft (GW1); an output shaft (GW2); an upstream gear set (VRS) with a first planetary gear set (P1) and a second planetary gear set (P2); a main gear set (HRS); an electric machine (EM) with a stator (S) and a rotor (R); and a plurality of shift elements (57, 07, 08, 04, 13, 14; 204, 234, 214; 304, 314; 403, 414, 445), each of a plurality of fixed transmission ratios (1 to 7; 21 to 25; 31 to 38) between the input shaft (GW1) and the output shaft (GW2) is shiftable by selective engagement of a respective three of the shift elements (57, 07, 08, 04, 13, 14; 204, 234, 214; 304, 314; 403, 414, 445), wherein the input shaft (GW1) is permanently connected to a first shaft (Wx1) of the upstream gear set (VRS), wherein the rotor (R) is permanently connected to a second shaft (Wx2) of the upstream gear set (VRS), wherein the output shaft (GW2) is permanently connected to a first shaft (Wy1, Wy21, Wy31, Wy41) of the main gear set (HRS), wherein the first and second planetary gear sets (P1, P2) of the upstream gear set (VRS) further include a third shaft (Wx3), a fourth shaft (Wx4), and a fifth shaft (Wx5) in addition to the first shaft (Wx1) and the second shaft (Wx2) such that the the first and second planetary gear sets (P1, P2) of the upstream gear set (VRS) collectively have precisely five shafts (Wx1, Wx2, Wx3, Wx4, Wx5), wherein the third shaft (Wx3) of the upstream gear set (VRS) is permanently connected to a second shaft (Wy2, Wy22, Wy32, Wy42) of the main gear set (HRS), wherein the third shaft (Wx3) of the upstream gear set (VRS) is connectable to the fourth shaft (Wx4) of the upstream gear set (VRS) by engaging a first one of the shift elements (57) such that the shafts (Wx1 to Wx5) of the upstream gear set (VRS) assume a rotational speed order of the second shaft (Wx2), the fifth shaft (Wx5), the third shaft (Wx3) together with the fourth shaft (Wx4), then the first shaft (Wx1), wherein the fourth shaft (Wx4) of the upstream gear set (VRS) is rotationally fixable by engaging a second one of the shift elements (07), and wherein the fifth shaft (Wx5) of the upstream gear set (VRS) is rotationally fixable by engaging a third one of the shift elements (08).

17. The transmission (G) of claim 16, wherein an absolute value of a stationary transmission ratio of the first planetary gear set (P1) of the upstream gear set (VRS) is greater than an absolute value of a stationary transmission ratio of the second planetary gear set (P2) of the upstream gear set (VRS).

18. The transmission (G) claim 16, wherein: the first and second planetary gear sets (P1, P2) of the upstream gear set (VRS) each include a first element (E11, E12), a second element (E21, E22), and a third element (E31, E32), the first element (E11, E12) formed by a sun gear of the respective planetary gear set (P1, P2), the second element (E21, E22) formed by a carrier of the respective planetary gear set (P1, P2) in the case of a minus gear set or by a ring gear of the respective planetary gear set (P1, P2) in the case of a plus gear set, the third element (E31, E32) formed by the ring gear of the respective planetary gear set (P1, P2) in the case of the minus gear set or by the carrier of the respective planetary gear set (P1, P2) in the case of the plus gear set; the third element (E32) of the second planetary gear set (P2) is an integral part of the first shaft (Wx1) of the upstream gear set (VRS); the first element (E11) of the first planetary gear set (P1) and the first element (E12) of the second planetary gear set (P2) are integral parts of the second shaft (Wx2) of the upstream gear set (VRS); the third element (E31) of the first planetary gear set (P1) is an integral part of the third shaft (Wx3) of the upstream gear set (VRS); the second element (E22) of the second planetary gear set (P2) is an integral part of the fourth shaft (Wx4) of the upstream gear set (VRS); and the second element (E21) of the first planetary gear set (P1) is an integral part of the fifth shaft (Wx5) of the upstream gear set (VRS).

19. The transmission (G) of claim 16, wherein: the main gear set (HRS) is a planetary gear set system (PS1) which comprises a third shaft (Wy3) and a fourth shaft (Wy4) in addition to the first and the second shafts (Wy1, Wy2) such that the main gear set (HRS) has precisely four shafts (Wy1, Wy2, Wy3, Wy4); the four shafts (Wy1 to Wy4) of the main gear set (HRS) have a rotational speed order of the second shaft (Wy2), the third shaft (Wy3), the first shaft (Wy1), then the fourth shaft (Wy4); the third shaft (Wy3) of the main gear set (HRS) is rotationally fixable by engaging a fourth one of the shift elements (04); the input shaft (GW1) is connectable to the fourth shaft (Wy4) of the main gear set (HRS) by engaging a fifth one of the shift elements (13); and the input shaft (GW1) is connectable to the third shaft (Wy3) by engaging a sixth one of the shift elements (14).

20. The transmission (G) of claim 19, wherein: the planetary gear set system (PS1) comprises a first planetary gear set (P3) and a second planetary gear set (P4), each of the first and second planetary gear sets (P3, P4) of the planetary gear set system (PS1) including a first element (E13, E14), a second element (E23, E24), and a third element (E33, E34), the first element (E13, E14) formed by a sun gear of the respective planetary gear set (P3, P4), the second element (E23, E24) formed by a carrier of the respective planetary gear set (P3, P4) in the case of a minus gear set or by a ring gear of the respective planetary gear set (P3, P4) in the case of a plus gear set, the third element (E33, E34) formed by the ring gear of the respective planetary gear set (P3, P4) in the case of the minus gear set or by the carrier of the respective planetary gear set (P3, P4) in the case of the plus gear set; the second element (E24) of the second planetary gear set (P4) of the planetary gear set system (PS1) and the third element (E33) of the first planetary gear set (P3) of the planetary gear set system (PS1) are integral parts of the first shaft (Wy1) of the main gear set (HRS); the first element (E13) of the first planetary gear set (P3) of the planetary gear set system (PS1) is an integral part of the second shaft (Wy2) of the main gear set (HRS); the second element (E23) of the first planetary gear set (P3) of the planetary gear set system (PS1) and the third element (E34) of the second planetary gear set (P4) of the planetary gear set system (PS1) are integral parts of the third shaft (Wy3) of the main gear set (HRS); and the first element (E14) of the second planetary gear set (P4) of the planetary gear set system (PS1) is an integral part of the fourth shaft (Wy4) of the main gear set (HRS).

21. The transmission (G) of claim 19, wherein: seven forward gears (1 to 7) and at least one reverse gear (R1, R2) between the input shaft (GW1) and the output shaft (GW2) are shiftable by selective engagement of three of the shift elements (57, 04, 07, 04/204, 13/234, 14/214); a first forward gear (1) results by engaging the second, the fourth, and the fifth shift elements (07, 04/204, 13/234); a second forward gear (2) results by engaging the first, the second, and the fifth shift elements (57, 07, 13/234); a third forward gear (3) results by engaging the second, the third, and the fifth shift elements (07, 08, 13/234); a fourth forward gear (4) results by engaging the second, the fifth, and the sixth shift elements (07, 13/234, 14/214); a fifth forward gear (5) results by engaging the second, the third, and the sixth shift elements (07, 08, 14/214); a sixth forward gear (6) results by engaging the first, the third, and the sixth shift elements (57, 08, 14/214); a seventh forward gear (7) results by engaging the first, the second, and the sixth shift elements (57, 07, 14/214); and the reverse gear (R1, R2) results by engaging the third and the fourth shift elements (08, 04/204) together with either the second shift element (07) or the first shift element (57).

22. The transmission (4) of claim 21, wherein: a first power-split drive mode (EDA1) between the input shaft (GW1), the electric machine (EM), and the output shaft (GW2) results by engaging the third shift element (08) and the fifth shift element (13/234); and a second power-split drive mode (EDA2) between the input shaft (GW1), the electric machine (EM), and the output shaft (GW2) results by engaging the fourth shift element (04/204) and the first shift element (57).

23. The transmission (G) of claim 19, wherein one or both of the fourth shift element (04/204) and the second shift element (07) is a form-fit shift element or a force-locking frictional shift element with disks that exclusively have non-lined friction faces.

24. The transmission (G) of claim 16, wherein: the main gear set (HRS) is a planetary gear set system (PS2) which comprises a third shaft (Wy23), a fourth shaft (Wy24), and a fifth shaft (Wy25) in addition to the first and the second shafts (Wy21, Wy22) such that the main gear set (HRS) has precisely five shafts (Wy21, Wy22, Wy23, Wy24, Wy25); the fifth shaft (Wy25) of the planetary gear set system (PS2) is permanently connected to the input shaft (GW1); the third shaft (Wy23) of the planetary gear set system (PS2) is rotationally fixable by engaging a fourth one of the shift elements (204); third shaft (Wy23) of the planetary gear set system (PS2) is connectable to the fourth shaft (Wy24) of the planetary gear set system (PS2) by engaging a fifth one of the shift elements (234) such that the five shafts (Wy21 to Wy25) of the planetary gear set system (PS2) have a rotational speed order of the second shaft (Wy22), the third shaft (Wy23) together with the fourth shaft (Wy24), the first shaft (Wy21), then the fifth shaft (Wy25); and the input shaft (GW1) is connectable to the third shaft (Wy23) of the planetary gear set system (PS2) by engaging a sixth one of the shift elements (214).

25. The transmission (G) of claim 24, wherein: the planetary gear set system (PS2) comprises two planetary gear sets (P23, P24), each of the two planetary gear sets (P23, P24) comprises a first element (E213, E214), a second element (E223, E224), and a third element (E233, E234), the first element (E213, E214) formed by a sun gear of the respective planetary gear set (P23, P24), the second element (E223, E224) formed by a carrier of the respective planetary gear set (P23, P24) in the case of a minus gear set or by a ring gear of the respective planetary gear set (P23, P24) in the case of a plus gear set, the third element (E233, E234) formed by the ring gear of the respective planetary gear set (P23, P24) in the case of the minus gear set or by the carrier of the respective planetary gear set (P23, P24) in the case of the plus gear set; the second element (E224) of the second planetary gear set (P24) of the planetary gear set system (PS2) and the third element (E233) of the first planetary gear set (P23) of the planetary gear set system (PS2) are integral parts of the first shaft (Wy1) of the main gear set (HRS); the first element (E213) of the first planetary gear set (P23) of the planetary gear set system (PS2) is an integral part of the second shaft (Wy22) of the main gear set (HRS); the second element (E223) of the first planetary gear set (P23) of the planetary gear set system (PS2) is an integral part of the third shaft (Wy23) of the main gear set (HRS); the third element (E234) of the second planetary gear set (P24) of the planetary gear set system (PS2) is an integral part of the fourth shaft (Wy24) of the main gear set (HRS); and the first element (E214) of the second planetary gear set (P24) of the planetary gear set system (PS2) is an integral part of the fifth shaft (Wy5) of the main gear set (HRS).

26. The transmission (G) of claim 24, wherein seven forward gears (1 to 7) and at least one reverse gear (R1, R2) between the input shaft (GW1) and the output shaft (GW2) are shiftable by selective engagement of three of the shift elements (57, 04, 07, 04/204, 13/234, 14/214); a first forward gear (1) results by engaging the second, the fourth, and the fifth shift elements (07, 04/204, 13/234); a second forward gear (2) results by engaging the first, the second, and the fifth shift elements (57, 07, 13/234); a third forward gear (3) results by engaging the second, the third, and the fifth shift elements (07, 08, 13/234); a fourth forward gear (4) results by engaging the second, the fifth, and the sixth shift elements (07, 13/234, 14/214); a fifth forward gear (5) results by engaging the second, the third, and the sixth shift elements (07, 08, 14/214); a sixth forward gear (6) results by engaging the first, the third, and the sixth shift elements (57, 08, 14/214); a seventh forward gear (7) results by engaging the first, the second, and the sixth shift elements (57, 07, 14/214); and the reverse gear (R1, R2) results by engaging the third and the fourth shift elements (08, 04/204) together with either the second shift element (07) or the first shift element (57).

27. The transmission (4) of claim 26, wherein: a first power-split drive mode (EDA1) between the input shaft (GW1), the electric machine (EM), and the output shaft (GW2) results by engaging the third shift element (08) and the fifth shift element (13/234); and a second power-split drive mode (EDA2) between the input shaft (GW1), the electric machine (EM), and the output shaft (GW2) results by engaging the fourth shift element (04/204) and the first shift element (57).

28. The transmission (G) of claim 24, wherein one or both of the fourth shift element (04/204) and the second shift element (07) is a form-fit shift element or a force-locking frictional shift element with disks that exclusively have non-lined friction faces.

29. The transmission (G) of claim 16, wherein: an interface (A) of the transmission (G) to a transmission-external drive unit is arranged coaxially with and at an opposite axial end of the transmission (G) to an interface (B) of the output shaft (GW2) to a transmission-internal or transmission-external differential gear; and the main gear set (HRS) has a greater axial distance to the interface (A) than the upstream gear set (VRS).

30. The transmission (G) of claim 16, wherein: an interface (B) of the output shaft (GW2) is a spur gear tooth system which intermeshes with a further spur gear tooth system of a shaft which is axially parallel to the output shaft (GW2); and the interface (B) of the output shaft (GW2) has a shorter axial distance to an interface (A) of the input shaft (GW1) than the upstream gear set (VRS).

31. The transmission (G) of claim 30, wherein the main gear set (HRS) is arranged axially between the interface (B) of the output shaft (GW2) and the upstream gear set (VRS).

32. The transmission (G) of claim 16, further comprising a connecting shaft (AN) and a separating clutch (K0), the connecting shaft (AN) connectable to the input shaft (GW1) via the separating clutch (K0).

33. A drive train for a motor vehicle, comprising an internal combustion engine (VKM), the transmission (G) of claim 16, and a differential gear (AG) connected to wheels (DW) of the motor vehicle, wherein the input shaft (GW1) of the transmission (G) is torsionally elastically connected via a torsional vibration damper (TS) to the internal combustion engine (VKM) either directly or by a separating clutch (K0), and the output shaft (GW2) of the transmission (G) is operatively connected to the differential gear (AG).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Exemplary embodiments of the invention are described in detail in the following with reference to the attached figures. Wherein:

[0036] FIG. 1 shows an abstract representation of a transmission according to example aspects of the invention;

[0037] FIG. 2 shows a schematic of a transmission according to first exemplary embodiment of the invention;

[0038] FIG. 3 shows a speed diagram of the main gear set according to the first exemplary embodiment;

[0039] FIG. 4 shows a shift pattern of the transmission according to the first exemplary embodiment;

[0040] FIG. 5 shows a schematic of a transmission according to a second exemplary embodiment of the invention;

[0041] FIG. 6 shows a shift pattern of the transmission according to the second exemplary embodiment;

[0042] FIG. 7 shows a schematic of a transmission according to a third exemplary embodiment of the invention;

[0043] FIG. 8 shows a shift pattern of the transmission according to the third exemplary embodiment;

[0044] FIG. 9 shows a schematic of a transmission according to a fourth exemplary embodiment of the invention;

[0045] FIG. 10 shows a shift pattern of the transmission according to the fourth exemplary embodiment; and

[0046] FIG. 11 shows a drive train of a motor vehicle.

DETAILED DESCRIPTION

[0047] Reference will now be made to embodiments of the invention, one or more examples of which are shown in the drawings. Each embodiment is provided by way of explanation of the invention, and not as a limitation of the invention. For example, features illustrated or described as part of one embodiment can be combined with another embodiment to yield still another embodiment. It is intended that the present invention include these and other modifications and variations to the embodiments described herein.

[0048] FIG. 1 shows an abstract representation of a transmission G according to example aspects of the invention. The transmission G includes an input shaft GW1, an output shaft GW2, an electric machine EM including a rotationally fixed stator S and a rotary rotor R, a front-mounted gear set VRS, and a main gear set HRS. The configuration of the front-mounted gear set VRS is represented by way of example, while the configuration of the main gear set HRS is merely indicated and various components of the main gear set HRS are not shown in detail. The main gear set HRS includes, in any case, several shafts, including a first shaft Wy1, which is permanently connected to the output shaft GW1, and a second shaft Wy2.

[0049] The front-mounted gear set VRS includes five shafts which are marked as first shaft Wx1, second shaft Wx2, third shaft Wx3, fourth shaft Wx4, and fifth shaft Wx5. The five shafts Wx1 to Wx5 of the front-mounted gear set VRS are formed by the elements of a first planetary gear set P1 and a second planetary gear set P2. Each of the two planetary gear sets P1, P2 includes a first element E11, E12, a second element E21, E22, and a third element E31, E32. The first element E11, E12 is formed by a sun gear of the respective planetary gear set P1, P2. When the planetary gear set is designed as a minus gear set, the second element E21, E22 is formed by a carrier of the respective planetary gear set P1, P2 and the third element E31, E32 is formed by the ring gear of the respective planetary gear set P1, P2. In the embodiment of the transmission G represented in FIG. 1, the planetary gear sets P1, P2 are designed as minus gear sets.

[0050] The third element E32 of the second planetary gear set P2 is an integral part of the first shaft Wx1 of the front-mounted gear set VRS, and is permanently connected to the input shaft GW1. The first element E11 of the first planetary gear set P1 and the first element E12 of the second planetary gear set P2 are permanently connected to one another and are integral parts of the second shaft Wx2 of the front-mounted gear set VRS, which is permanently connected to the rotor R of the electric machine EM. The third element E31 of the first planetary gear set P1 is an integral part of the third shaft Wx3 of the front-mounted gear set VRS, which is permanently connected to the second shaft Wy2 of the main gear set HRS. The second element E22 of the second planetary gear set P2 is an integral part of the fourth shaft Wx4 of the front-mounted gear set VRS. The second element E21 of the first planetary gear set P1 is an integral part of the fifth shaft Wx5 of the front-mounted gear set VRS.

[0051] The transmission G includes a plurality of shift elements, including a first shift element 57, a second shift element 07, and a third shift element 08. By way of engagement of the first shift element 57, the third front-mounted gear set shaft Wx3 is connected to the fourth front-mounted gear set shaft Wx4. By way of engagement of the second shift element 07, the fourth front-mounted gear set shaft Wx4 is rotationally fixed, in that it is connected to a rotationally fixed component GG of the transmission G. The rotationally fixed component can be formed, for example, by the housing of the transmission G. By way of engagement of the third shift element 08, the fifth shaft Wx5 of the front-mounted gear set VRS is rotationally fixable in the same way.

[0052] It is to be noted that the main gear set HRS can have various designs. The main gear set HRS can include, for example, only one single planetary gear set, or even a plurality of planetary gear sets. The main gear set could also be designed as a countershaft transmission. Shift elements can be associated with the main gear set HRS, with the aid of which individual shafts of the main gear set HRS is rotationally fixable or connectable to the input shaft GW1. By way of the shift elements, individual shafts of the main gear set HRS are also connectable to one another. Specific embodiments of transmissions G are described in detail in the following exemplary embodiments.

[0053] The input shaft GW1 includes an interface A to a transmission-external drive unit. The output shaft includes an interface B to a transmission-external or transmission-internal differential gear. The interfaces A, B are arranged coaxially to each other and at opposite axial ends of the transmission G in this case. The interface A is designed for transmitting a turning motion from the transmission-external drive unit to the transmission G and can be designed, for example, as a flange or as a spline. The interface A can be formed on the input shaft GW1 or on a connecting shaft which can be connected to the input shaft GW1. The interface A can also be formed, for example, on a hydrodynamic torque converter which is connected to the input shaft GW1 and acts as a starting component. The interface B of the output shaft GW2 is aligned toward driving wheels of the motor vehicle in order to transmit a turning motion from the output shaft GW2, with the intermediate connection of the differential gear.

[0054] FIG. 2 shows a schematic of a transmission G according to a first exemplary embodiment of the invention. The main gear set HRS includes, in this case, a planetary gear set system PS1 which includes a first planetary gear set P3 and a second planetary gear set P4. Each of the two planetary gear sets P3, P4 includes a first element E13, E14, a second element E23, E24, and a third element E33, E34. The first element E13, E14 is formed by a sun gear of the respective planetary gear set P3, P4. When the planetary gear set is designed as a minus gear set, the second element E23, E24 is formed by a carrier of the respective planetary gear set P3, P4 and the third element E33, E34 is formed by the ring gear of the respective planetary gear set P3, P4. In the first embodiment of the transmission G represented in FIG. 2, the planetary gear sets P3, P4 are designed as minus gear sets.

[0055] The planetary gear set system PS1 includes precisely four shafts in this case, namely the first shaft Wy1 connected to the output shaft GW2, the second shaft Wy2 connected to the third shaft Wx3 of the front-mounted gear set VRS, a third shaft Wy3, and a fourth shaft Wy4. A planetary gear set system consisting of two individual planetary gear sets which, together, form four shafts, can also be described by its kinematics. Examples thereof are the so-called Ravigneaux gear set or the Simpson gear set. The four shafts of these types of planetary gear set systems have a rotational speed order which is described in detail, by way of example, further below with reference to FIG. 3.

[0056] In the exemplary embodiment according to FIG. 2, the first shaft Wy1 of the main gear set HRS is permanently connected to the third element E33 of the first planetary gear set P3 and to the second element E24 of the second planetary gear set P4. The second shaft Wy2 of the main gear set HRS is permanently connected to the first element E13 of the first planetary gear set P3. The third shaft Wy3 of the main gear set HRS is permanently connected to the second element E23 of the first planetary gear set P3 and to the third element E34 of the second planetary gear set P4. In addition, the third shaft Wy3 of the main gear set HRS is rotationally fixable by engaging a fourth shift element 04. The fourth shaft Wy4 of the main gear set HRS is permanently connected to the first element E14 of the second planetary gear set P4 and is connectable to the input shaft GW1 via a fifth shift element 13. The third shaft Wy3 of the main gear set HRS is connectable to the input shaft GW1 by engaging a sixth shift element 14.

[0057] The transmission G according to the first exemplary embodiment represented in FIG. 1 includes a connecting shaft AN which is connectable to the input shaft GW1 via a separating clutch K0. These two components are optional components of the transmission G. The interface A is formed on the connecting shaft AN.

[0058] FIG. 3 shows a speed diagram of the planetary gear set system PS1 according to the transmission G of the first exemplary embodiment represented in FIG. 2. The four vertical lines describe the rotational speed of each of the four main gear set shafts Wy1 to Wy4 in relationship to a predefined rotational speed n of the input shaft GW1, which has been standardized to the value one. The distance between the vertical lines results from the stationary transmission ratios of the planetary gear sets P3, P4. The representation shown in FIG. 3 is not full scale.

[0059] Circles arranged on the vertical lines show the effect of the six shift elements 57, 07, 08, 04, 13, 14. When, for example, the input shaft GW1 is connected to the fourth shaft Wy4 by engaging the fifth shift element 13, the fourth shaft Wy4 and the input shaft GW1 have a speed ratio equal to one. When the fourth shift element 04 is engaged, the rotational speed of the third shaft Wy3 is equal to zero. The three shift elements 57, 07, 08 associated with the front-mounted gear set VRS yield their effect by way of engagement of two of the three shift elements 57, 07, 08. When the first shift element 57 and the second shift element 07 are engaged, the second shaft W2y is rotationally fixed and, therefore, assumes the value zero. When the first shift element 57 and the third shift element 08 are engaged, the rotational speed of the second shaft W2y is reduced in relation to the rotational speed n of the input shaft GW1. When the second shift element 07 and the third shift element 08 are engaged, the rotational speed of the second shaft W2y is also reduced in relation to the rotational speed n of the input shaft GW1, although to a lesser extent than during the engagement of the first shift element 57 and the third shift element 08.

[0060] By predefining the rotational speeds at two of the four shafts Wy1 to Wy4 of the main gear set HRS, the rotational speeds of all four shafts Wy1 to Wy4 of the main gear set HRS are established. This is apparent on the basis of a straight-line connection of two of the circles. According thereto, the rotational speeds of the four shafts Wy1 to Wy4 are linearly dependent on one another as soon as the rotational speed of two of the four shafts Wy1 to Wy4 has been defined. The sequence of the vertical lines in the speed diagram shows the rotational speed order in this case, which, in the example given, assumes the following sequence: second shaft Wy2, third shaft Wy3, first shaft Wy1, fourth shaft Wy4.

[0061] FIG. 4 shows a shift pattern which can be applied for the transmission G according to the first exemplary embodiment. In the rows of the shift pattern, two reverse gears R1, R2 and a first to seventh forward gear 1 to 7 are indicated. In the columns of the shift pattern, an X indicates which of the shift elements 04, 07, 08, 13, 14, 57 is engaged in which gear 1 through 7 and R1, R2. The gears refer to fixed transmission ratios between the input shaft GW1 and the output shaft GW2 in this case. In combination with the shift pattern represented in FIG. 4 and the speed diagram represented in FIG. 3, the gear implementation of the transmission G becomes clear. A first forward gear 1 results from engaging the fourth shift element 04 and the fifth shift element 13. As a result, the transmission ratio between the input shaft and the output shaft is already established. The rotational speeds of the remaining shafts are also established by engaging the second shift element 07. A second forward gear 2 results from engaging the first shift element 57, the second shift element 07, and the fifth shift element 13. A third forward gear 3 results from engaging the second shift element 07, the third shift element 08, and the fifth shift element 13. A fourth forward gear 4 results from engaging the fifth shift element 13 and the sixth shift element 14. As a result, the transmission ratio between the input shaft and the output shaft is already established. The rotational speeds of the remaining shafts are also established by engaging the second shift element 07. A fifth forward gear 5 results from engaging the second shift element 07, the third shift element 08, and the sixth shift element 14. A sixth forward gear 6 results from engaging the first shift element 57, the third shift element 08, and the sixth shift element 14. A seventh forward gear 7 results from engaging the first shift element 57, the second shift element 07, and the sixth shift element 14. A first reverse gear marked as R1 results from engaging the first shift element 57, the third shift element 08, and the fourth shift element 04. A second reverse gear R2 can be implemented by engaging the second shift element 07, the third shift element 08, and the fourth shift element 04. A first power-split drive mode EDA1 results by engaging the third shift element 08 and the fifth shift element 13. A second power-split drive mode EDA2 results by engaging the first shift element 57 and the fourth shift element 04. An electric drive mode E1 results by engaging the third shift element 08 and the fourth shift element 04.

[0062] FIG. 5 shows a schematic of a transmission G according to a second exemplary embodiment of the invention. The main gear set HRS includes, in this case, a planetary gear set system PS2 which includes a first planetary gear set P23 and a second planetary gear set P24. Each of the two planetary gear sets P23, P24 includes a first element E213, E214, a second element E223, E224, and a third element E233, E234. The first element E213, E214 is formed by a sun gear of the respective planetary gear set P23, P24. When the planetary gear set is designed as a minus gear set, the second element E223, E224 is formed by a carrier of the respective planetary gear set P23, P24 and the third element E233, E234 is formed by the ring gear of the respective planetary gear set P23, P24. In the second exemplary embodiment of the transmission G represented in FIG. 5, the planetary gear sets P23, P24 are designed as minus gear sets.

[0063] The planetary gear set system PS2 includes precisely five shafts in this case, namely the first shaft Wy21 connected to the output shaft GW2, the second shaft Wy22 connected to the third shaft Wx3 of the front-mounted gear set VRS, a third shaft Wy23, a fourth shaft Wy24, and a fifth shaft Wy25. In the exemplary embodiment according to FIG. 5, the first shaft Wy21 of the main gear set HRS is permanently connected to the third element E233 of the first planetary gear set P23 and to the second element E224 of the second planetary gear set P24. The second shaft Wy22 of the main gear set HRS is permanently connected to the first element E213 of the first planetary gear set P23. The third shaft Wy23 of the main gear set HRS is permanently connected to the second element E223 of the first planetary gear set P23. In addition, the third shaft Wy23 of the main gear set HRS is rotationally fixable by engaging a fourth shift element 204. The fourth shaft Wy24 of the main gear set HRS is permanently connected to the third element E234 of the second planetary gear set P24. The fifth shaft Wy25 of the main gear set HRS is permanently connected to the first element E214 of the second planetary gear set P24 and is permanently connected to the input shaft GW1. The third shaft Wy23 of the main gear set HRS is connectable to the fourth shaft Wy24 of the main gear set HRS by engaging a fifth shift element 234, and is connectable to the input shaft GW1 by engaging a sixth shift element 214.

[0064] The difference between the first exemplary embodiment and the second exemplary embodiment is therefore essentially the coupling between the first element E14, E214 of the second planetary gear set P4, P24 and the input shaft GW1, on the one hand, and the coupling between the second element E23, E223 of the first planetary gear set P3, P23 and the third element E34, E234 of the second planetary gear set P4, P24, on the other hand. One of the two couplings is designed as a permanently rotationally fixed connection in this case, while the other of the two components is designed as a connection which can be established with the aid of the fifth shift element 13, 234.

[0065] FIG. 6 shows a shift pattern which can be applied for the transmission G according to the second exemplary embodiment. In the rows of the shift pattern, two reverse gears R1, R2, a first through seventh forward gear 1 to 7, two power-split drive modes EDA1, EDA2 and an electric drive mode E1 are indicated. In the columns of the shift pattern, an X indicates which of the shift elements 204, 07, 08, 234, 214, 57 is engaged in which gear 1 to 7 and R1, R2, and operating modes EDA1, EDA2, E1.

[0066] FIG. 7 shows a schematic of a transmission G according to a third exemplary embodiment of the invention. The main gear set HRS includes a single planetary gear set P33 in this case, which includes a first element E313, a second element E323, and a third element E333. The first element E313 is formed by a sun gear of the planetary gear set P33. When the planetary gear set P33 is designed as a minus gear set as represented in FIG. 7, the second element E323 is formed by a carrier of the planetary gear set P33 and the third element E333 is formed by a ring gear of the planetary gear set P33. In a design of the planetary gear set P33 as a plus gear set, the second element E323 would be formed by the ring gear of the planetary gear set P33 and the second element E333 would be formed by the carrier of the planetary gear set P33.

[0067] The main gear set HRS according to the third exemplary embodiment includes precisely three shafts, namely the first shaft Wy31 connected to the output shaft GW2, the second shaft Wy32 connected to the third shaft Wx3 of the front-mounted gear set VRS, and a third shaft Wy33. The second element E323 of the planetary gear set P33 is an integral part of the first shaft Wy31 of the main gear set HRS. The third element E333 of the planetary gear set P33 is an integral part of the second shaft Wy32 of the main gear set HRS. The first element E313 of the planetary gear set P33 is an integral part of the third shaft Wy33 of the main gear set HRS. The third shaft Wy33 is rotationally fixable by engaging a fourth shift element 304. The input shaft GW1 is connectable to the third shaft Wy33 by engaging a fifth shift element.

[0068] In the transmission G according to the third exemplary embodiment, the interface B is designed as a spur gear tooth system which intermeshes with a further spur gear tooth system of a shaft which is axially parallel to the output shaft and is not represented in FIG. 7. The main gear set HRS is arranged axially between the interface B and the front-mounted gear set VRS in this case. The interface B is arranged axially between the interface A to the transmission-external drive unit and the front-mounted gear set VRS.

[0069] FIG. 8 shows a shift pattern which can be applied for the transmission G according to the third exemplary embodiment. In the rows of the shift pattern, a first to fifth forward gear 21 through 25 are indicated. In the columns of the shift pattern, an X indicates which of the shift elements 304, 07, 08, 234, 314, 57 is engaged in which gear 21 to 25. The gears refer to fixed transmission ratios between the input shaft GW1 and the output shaft GW2 in this case.

[0070] FIG. 9 shows a schematic of a transmission G according to a fourth exemplary embodiment of the invention. The main gear set HRS includes, in this case, a planetary gear set system PS3 which includes a first planetary gear set P43 and a second planetary gear set P44. Each of the two planetary gear sets P43, P44 includes a first element E413, E414, a second element E423, E424, and a third element E433, E434. The first element E413, E414 is formed by a sun gear of the respective planetary gear set P43, P44. When one of the planetary gear sets P43, P44 is designed as a minus gear set, the second element E423, E424 is formed by a carrier of the respective planetary gear set P43, P44 and the third element E433, E434 is formed by a ring gear of the respective planetary gear set P43, P44. When one of the planetary gear sets P43, P44 is designed as a plus gear set, the second element E423, E424 is formed by the ring gear of the respective planetary gear set P43, P44 and the third element E433, E434 is formed by the carrier of the respective planetary gear set P43, P44. In the fourth exemplary embodiment of the transmission G represented in FIG. 9, the first planetary gear set P43 is designed as a plus gear set and the second planetary gear set P44 is designed as a minus gear set.

[0071] The planetary gear set system PS3 includes precisely four shafts in this case, namely the first shaft Wy41 connected to the output shaft GW2, the second shaft Wy42 connected to the third shaft Wx3 of the front-mounted gear set VRS, a third shaft Wy43, and a fourth shaft Wy44. A planetary gear set system consisting of two individual planetary gear sets which, together, form four shafts, can also be described by its kinematics. The present configuration of the planetary gear set system corresponds to the known Ravigneaux gear set. The embodiment represented in FIG. 9 is to be considered merely schematically. In an implementation of this example, the main gear set HRS would be designed in the known design of a Ravigneaux gear set, i.e., including a single ring gear and a common set of radially outer planet gears.

[0072] In the exemplary embodiment according to FIG. 9, the second element E423 of the first planetary gear set P43 and the third element E434 of the second planetary gear set P44 are integral parts of the first shaft Wy41 of the main gear set HRS which is permanently connected to the output shaft GW2. The first element E413 of the first planetary gear set P43 is an integral part of the second shaft Wy42 of the main gear set HRS, which is permanently connected to the third shaft Wx3 of the front-mounted gear set VRS.

[0073] The third element E433 of the first planetary gear set P43 and the second element E424 of the second planetary gear set P44 are integral parts of the third shaft Wy43 of the main gear set HRS. The first element E414 of the second planetary gear set P44 is an integral part of the fourth shaft Wy44 of the main gear set HRS. The third shaft Wy43 is rotationally fixable by engaging a fourth shift element 403. The fourth shaft Wy44 is connectable to the input shaft GW1 by engaging a fifth shift element 414 and is connectable to the second shaft Wy42 by engaging a sixth shift element 445.

[0074] FIG. 10 shows a shift pattern which can be applied for the transmission G according to the fourth exemplary embodiment. In the rows of the shift pattern, one reverse gear 3R and a first to eighth forward gear 31 through 38 are indicated. In the columns of the shift pattern, an X indicates which of the shift elements 403, 07, 08, 414, 445, 57 is engaged in which gear 31 to 38, 3R. The gears refer to fixed transmission ratios between the input shaft GW1 and the output shaft GW2 in this case.

[0075] FIG. 11 schematically shows a drive train of a motor vehicle. An internal combustion engine VKM is connected via a torsional vibration damper TS to the connecting shaft AN of the transmission G. The transmission G represented in FIG. 11 corresponds to the first exemplary embodiment of the invention represented in FIG. 1. This is to be considered merely as an example. The internal combustion engine VKM could also be connected via the torsional vibration damper TS directly to the input shaft GW1 of the transmission G. The drive train could be designed with any of the present exemplary embodiments. The drive train could also contain a hydrodynamic torque converter which is to be arranged in the power flow between the internal combustion engine VKM and the input shaft GW1 of the transmission G. Such a torque converter can also include a direct drive or lockup clutch. A person skilled in the art will freely configure the arrangement and the spatial position of the individual components of the drive train depending on the external peripheral conditions. The output shaft GW2 is connected to a differential gear AG, via which the power present at the output shaft GW2 is distributed to driving wheels DW of the motor vehicle.

[0076] Modifications and variations can be made to the embodiments illustrated or described herein without departing from the scope and spirit of the invention as set forth in the appended claims.

REFERENCE CHARACTERS

[0077] G transmission [0078] GG rotationally fixed component [0079] GW1 input shaft [0080] GW2 output shaft [0081] A interface [0082] B interface [0083] VRS front-mounted gear set [0084] Wx1 first shaft of the front-mounted gear set [0085] Wx2 second shaft of the front-mounted gear set [0086] Wx3 third shaft of the front-mounted gear set [0087] Wx4 fourth shaft of the front-mounted gear set [0088] Wx5 fifth shaft of the front-mounted gear set [0089] 57 first shift element [0090] 07 second shift element [0091] 08 third shift element [0092] P1 first planetary gear set [0093] E11 first element of the first planetary gear set [0094] E21 second element of the first planetary gear set [0095] E31 third element of the first planetary gear set [0096] P2 second planetary gear set [0097] E12 first element of the second planetary gear set [0098] E22 second element of the second planetary gear set [0099] E32 third element of the second planetary gear set [0100] HRS main gear set [0101] PS1 planetary gear set system [0102] P3 first planetary gear set of the planetary gear set system [0103] E13 first element of the first planetary gear set [0104] E23 second element of the first planetary gear set [0105] E33 third element of the first planetary gear set [0106] P4 second planetary gear set of the planetary gear set system [0107] E14 first element of the second planetary gear set [0108] E24 second element of the second planetary gear set [0109] E34 third element of the third planetary gear set [0110] Wy1 first shaft of the main gear set [0111] Wy2 second shaft of the main gear set [0112] Wy3 third shaft of the main gear set [0113] Wy4 fourth shaft of the main gear set [0114] 04 fourth shift element [0115] 13 fifth shift element [0116] 14 sixth shift element [0117] 1-7 first to seventh forward gear [0118] R1, R2 reverse gear [0119] PS2 planetary gear set system [0120] P23 first planetary gear set of the planetary gear set system [0121] E213 first element of the first planetary gear set [0122] E223 second element of the first planetary gear set [0123] E233 third element of the first planetary gear set [0124] P24 second planetary gear set of the planetary gear set system [0125] E214 first element of the second planetary gear set [0126] E224 second element of the second planetary gear set [0127] E234 third element of the third planetary gear set [0128] Wy21 first shaft of the main gear set [0129] Wy22 second shaft of the main gear set [0130] Wy23 third shaft of the main gear set [0131] Wy24 fourth shaft of the main gear set [0132] 204 fourth shift element [0133] 234 fifth shift element [0134] 214 sixth shift element [0135] P33 planetary gear set of the main gear set [0136] E313 first element of the main gear set [0137] E323 second element of the main gear set [0138] E333 third element of the main gear set [0139] Wy31 first shaft of the main gear set [0140] Wy32 second shaft of the main gear set [0141] Wy33 third shaft of the main gear set [0142] 304 fourth shift element [0143] 314 fifth shift element [0144] 21-25 first to fifth forward gear [0145] PS3 planetary gear set system [0146] P43 first planetary gear set of the planetary gear set system [0147] E413 first element of the first planetary gear set [0148] E423 second element of the first planetary gear set [0149] E433 third element of the first planetary gear set [0150] P44 second planetary gear set of the planetary gear set system [0151] E414 first element of the second planetary gear set [0152] E424 second element of the second planetary gear set [0153] E434 third element of the third planetary gear set [0154] Wy41 first shaft of the main gear set [0155] Wy42 second shaft of the main gear set [0156] Wy43 third shaft of the main gear set [0157] Wy44 fourth shaft of the main gear set [0158] 403 fourth shift element [0159] 414 fifth shift element [0160] 445 sixth shift element [0161] 31-38 first to eighth forward gear [0162] 3R reverse gear [0163] EM electric machine [0164] R rotor [0165] S stator [0166] K0 separating clutch [0167] VKM internal combustion engine [0168] DW wheels [0169] AG differential gear [0170] TS torsional vibration damper