Transmission for a Drive Train of a Vehicle

Abstract

A transmission (1) includes an input shaft (2), a first and a second output shaft (3, 4), and a differential (7) with a first and a second planetary gear set (5, 6). A first gear set element of the first planetary gear set (5) is connected to the input shaft (2) for conjoint rotation. A second gear set element of the first planetary gear set (5) is connected to a first gear set element of the second planetary gear set (6) conjoint rotation. A third gear set element of the first planetary gear set (5) is connected to the first output shaft (3) for conjoint rotation. A second gear set element of the second planetary gear set (6) is connected to the second output shaft (4) for conjoint rotation. A third gear set element of the second planetary gear set (6) is connected to a stationary component for conjoint rotation. The second planetary gear set (6) is axially adjacent to the first planetary gear set (5) and the planet gears (5.4) of the first planetary gear set (5) do not axially overlap the planet gears (6.4) of the second planetary gear set (6).

Claims

1-11: (canceled)

12. A transmission (1) for a drive train of a vehicle (100), comprising: an input shaft (2); a first output shaft (3); a second output shaft (4); and a differential arranged in power flow between the input shaft (2) and the first and second output shafts (3, 4), the differential comprising a first planetary gear set (5) with a plurality of planet gears (5.4) and a plurality of gear set elements, a first output torque transmittable onto the first output shaft (3) by the first planetary gear set (5), the differential comprising a second planetary gear set (6) with a plurality of planet gears (6.4) and a plurality of gear set elements, a support torque of the first planetary gear set (5) convertible in the second planetary gear set (6) such that a second output torque corresponding to the first output torque is transmittable onto the second output shaft (4), wherein a first gear set element of the gear set elements of the first planetary gear set (5) is connected to the input shaft (2) for conjoint rotation, wherein a second gear set element of the gear set elements of the first planetary gear set (5) is connected to a first gear set element of the gear set elements of the second planetary gear set (6) for conjoint rotation, wherein a third gear set element of the gear set elements of the first planetary gear set (5) is connected to the first output shaft (3) for conjoint rotation, wherein a second gear set element of the gear set elements of the second planetary gear set (6) is connected to the second output shaft (4) for conjoint rotation, wherein a third gear set element of the second planetary gear set (6) is connected to a stationary component for conjoint rotation, wherein the second planetary gear set (6) is axially adjacent the first planetary gear set (5), and the planet gears (5.4) of the first planetary gear set (5) do not axially overlap the planet gears (6.4) of the second planetary gear set (6), and wherein an outer diameter of the planet gears (5.4) of the first planetary gear set (5) are greater than an outer diameter of the planet gears (6.4) of the second planetary gear set (6).

13. The transmission (1) of claim 12, wherein the first gear set element of the first planetary gear set (5) comprises a sun gear (5.1), the second gear set element of the first planetary gear set (5) comprises a ring gear (5.2), and the third gear set element of the first planetary gear set (5) comprises a planet carrier (5.3).

14. The transmission (1) of claim 12, wherein the first gear set element of the second planetary gear set (6) comprises a sun gear (6.1), the second gear set element of the second planetary gear set (6) comprises a ring gear (6.2), and the third gear set element of the second planetary gear set (6) comprises a planet carrier (6.3).

15. The transmission (1) of claim 12, wherein: the first gear set element of the first planetary gear set (5) comprises a sun gear (5.1), the second gear set element of the first planetary gear set (5) comprises a ring gear (5.2), and the third gear set element of the first planetary gear set (5) comprises a planet carrier (5.3); the first gear set element of the second planetary gear set (6) comprises a sun gear (6.1), the second gear set element of the second planetary gear set (6) comprises a ring gear (6.2), and the third gear set element of the second planetary gear set (6) comprises a planet carrier (6.3); and the ring gear (5.2) of the first planetary gear set (5) has a larger outer diameter than the sun gear (6.1) of the second planetary gear set (6), and the sun gear (6.1) of the second planetary gear set (6) is arranged at least indirectly axially at the ring gear (5.2) of the first planetary gear set (5).

16. The transmission (1) of claim 12, further comprising a bearing (7) for mounting the second output shaft (4), the bearing (7) arranged at least partially radially inside the second planetary gear set (6).

17. The transmission (1) of claim 12, further comprising an oil feed (8) for the second output shaft (4) arranged at least partially radially inside the second planetary gear set (6).

18. The transmission (1) of claim 17, wherein the oil feed (8) comprises a ring element (9) arranged radially between a stationary component and the second output shaft (4).

19. The transmission (1) of claim 12, further comprising: a bearing (7) for mounting the second output shaft (4), the bearing (7) arranged at least partially radially inside the second planetary gear set (6); and an oil feed (8) for the second output shaft (4) arranged at least partially radially inside the second planetary gear set (6), wherein the oil feed (8) is arranged axially adjacent the bearing (7) for mounting the second output shaft (4).

20. The transmission (1) of claim 19, wherein the oil feed (8) comprises a ring element (9) arranged radially between a stationary component and the second output shaft (4).

21. The transmission (1) of claim 12, wherein the outer diameter of the planet gears (5.4) of the first planetary gear set (5) is at least twice as great as the outer diameter of the planet gears (6.4) of the second planetary gear set (6).

22. The transmission (1) of claim 12, wherein the second planetary gear set (6) is arranged with the gear set elements of the second planetary gear set (6) radially outward of a rotation axis (B) of each of the planet gears (5.4) of the first planetary gear set (5).

23. A vehicle (100), comprising a drive train with a drive unit (10) and the transmission (1) of claim 12.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0032] One exemplary embodiment of the invention is explained in greater detail in the following with reference to the schematic drawings, in which identical or similar elements are provided with the same reference characters. Therein:

[0033] FIG. 1 shows a highly schematic view of a vehicle with a drive train, which has a transmission according to example aspects of the invention;

[0034] FIG. 2 shows a highly schematic view of a cutout portion of the transmission according to example aspects of the invention; and

[0035] FIG. 3 shows a detailed schematic sectional view of a cutout portion of the transmission according to example aspects of the invention.

DETAILED DESCRIPTION

[0036] 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.

[0037] FIG. 1 shows a vehicle 100 having a first axle 101 with two vehicle wheels R1, R2 and a second axle 102 with two vehicle wheels R3, R4. In the present case, the first axle 101 is in the form of a rear drive axle of the vehicle 100 and has a drive train with a drive unit 10, which is in the form of an electric machine, and a transmission 1 according to example aspects of the invention. The drive unit 10 is designed to generate drive power and is drivingly connected to the transmission 1. Therefore, the vehicle 100 is in the form of an electric vehicle, i.e., an electrically driven vehicle. The drive unit 10 is arranged coaxially with the transmission 1 and transversely to the vehicle longitudinal direction and is connected via an integral differential in the transmission 1 to the vehicle wheels R1, R2 on the first axle 101. In the present case, a further drive train is not arranged on the second axle 102, i.e., on the front axle of the vehicle 100, as a result of which costs, weight and installation space are reduced. Alternatively, the drive train can be arranged on the front axle of the vehicle 100 rather than on the rear axle. In order to implement an all-wheel drive system, a further drive train can be arranged on the second axle 102 and drivingly connected to the vehicle wheels R3, R4 on this wheel axle 102.

[0038] FIG. 2 and FIG. 3 show a cutout portion of the transmission 1 according to example aspects of the invention, the integral differential being the focus in the present case. The transmission 1 has an input shaft 2, a first output shaft 3, a second output shaft 4, and a first planetary gear set 5 and a second planetary gear 6. The two planetary gear sets 5, 6 form the integral differential and are arranged in the power flow between the input shaft 2 and the two output shafts 3, 4. A first output torque is transmittable onto the first output shaft 3 by the first planetary gear set 5. A support torque of the first planetary gear set 5 is convertible in the second planetary gear set 6 such that a second output torque, which corresponds to the first output torque, is transmittable onto the second output shaft 4.

[0039] A first gear set element of the first planetary gear set 5 is in the form of a sun gear 5.1 and is connected to the input shaft 2 for conjoint rotation. A second gear set element of the first planetary gear set 5 is in the form of a ring gear 5.2 and is connected to a first gear set element, which is in the form of a sun gear 6.1, of the second planetary gear set 6 for conjoint rotation. A third gear set element of the first planetary gear set 5 is in the form of a planet carrier 5.3 and is connected to the first output shaft 3 for conjoint rotation. Multiple planet gears 5.4 are rotatably mounted on the planet carrier 5.3 of the first planetary gear set 5, each planet gear 5.4 meshing with the sun gear 5.1 and the ring gear 5.2 of the first planetary gear set 5. A second gear set element of the second planetary gear set 6 is in the form of a ring gear 6.2 and is connected to the second output shaft 4 for conjoint rotation. A third gear set element of the second planetary gear set 6 is in the form of a planet carrier 6.3 and is connected to a stationary component, which is in the form of a housing G, for conjoint rotation.

[0040] The second planetary gear set 6 is axially adjacent to the first planetary gear set 5, and the planet gears 5.4 of the first planetary gear set 5 do not axially overlap the planet gears 6.4 of the second planetary gear set 6. The two planetary gear sets 5, 6 rotate about a common rotation axis A of the transmission 1. The two output shafts 3, 4 are arranged on the common rotation axis A of the transmission 1 and are connected to a respective wheel of the vehicle. This is shown in a simplified manner in the present case by a respective arrow at the respective output shaft 3, 4.

[0041] The planet gears 5.4 of the first planetary gear set 5 have a larger outer diameter than the planet gears 6.4 of the second planetary gear set 6. The second planetary gear set 6 is arranged with its gear set elements in a radial direction outside a rotation axis B of the respective planet gear 5.4 of the first planetary gear set 5. Therefore, the planet gears 6.4 of the second planetary gear set 6 are radially further remote from the common rotation axis A than the planet gears 5.4 of the first planetary gear set 5. As a result, installation space is created radially inside the second planetary gear set 6. This installation space can be advantageously used, in particular, for supporting points and an oil feed.

[0042] FIG. 3 shows the cutout portion of the transmission according to FIG. 2 in greater detail. The ring gear 5.2 of the first planetary gear set 5 has a greater outer diameter than the sun gear 6.1 of the second planetary gear set 6. The sun gear 6.1 of the second planetary gear set 6 is arranged axially at the ring gear 5.2 of the first planetary gear set 5 and is connected thereto for conjoint rotation.

[0043] A bearing element 7 for mounting the second output shaft 4 is arranged radially inside the second planetary gear set 6 and axially overlapping the second planetary gear set 6. Furthermore, an oil feed 8 for the second output shaft 4 is arranged radially inside the second planetary gear set 6 and axially overlapping the second planetary gear set 6. The oil feed 8 for the second output shaft 4 and the bearing element 7 for mounting the second output shaft 4 are arranged axially adjacent to each other.

[0044] The oil feed 8 includes a ring element 9, which is arranged radially between a stationary component, which is in the form of a housing G, and the second output shaft 4. The bearing element 7 is in the form of a grooved ball bearing and is supported against the stationary component, which is in the form of a housing G.

[0045] Due to the fact that the particular outer diameter of the planet gears 5.4 of the first planetary gear set 5 is more than twice (2X) as great as the particular outer diameter of the planet gears 6.4 of the second planetary gear set 6, the overall gear ratio of the integral differential is greatly increased. This increase in the overall gear ratio is neutral with respect to installation space due to the advantageous arrangement of the bearing element 7 and of the oil feed 8 inside the second planetary gear set 6, and therefore results in a particularly compact transmission 1.

[0046] 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. In the claims, reference characters corresponding to elements recited in the detailed description and the drawings may be recited. Such reference characters are enclosed within parentheses and are provided as an aid for reference to example embodiments described in the detailed description and the drawings. Such reference characters are provided for convenience only and have no effect on the scope of the claims. In particular, such reference characters are not intended to limit the claims to the particular example embodiments described in the detailed description and the drawings.

REFERENCE CHARACTERS

[0047] 1 transmission [0048] 2 input shaft [0049] 3 first output shaft [0050] 4 second output shaft [0051] 5 first planetary gear set [0052] 5.1 sun gear of the first planetary gear set [0053] 5.2 ring gear of the first planetary gear set [0054] 5.3 planet carrier of the first planetary gear set [0055] 5.4 planet gear of the first planetary gear set [0056] 6 second planetary gear set [0057] 6.1 sun gear of the second planetary gear set [0058] 6.2 ring gear of the second planetary gear set [0059] 6.3 planet carrier of the second planetary gear set [0060] 6.4 planet gear of the second planetary gear set [0061] 7 bearing element [0062] 8 oil feed [0063] 9 ring element [0064] 10 prime mover [0065] G housing [0066] A rotation axis [0067] 100 vehicle [0068] 101 first axle [0069] 102 second axle [0070] R1 vehicle wheel [0071] R2 vehicle wheel [0072] R3 vehicle wheel [0073] R4 vehicle wheel