Transmission for a motor vehicle, and drive train for a motor vehicle

Abstract

A transmission for a motor vehicle having an input shaft, an output shaft, a plurality of planetary gear sets, a plurality of shift elements, and an electric machine arranged axially parallel to the input shaft and operatively connected to the input shaft with a constant transmission ratio via a spur gear drive or a flexible traction drive mechanism. Various gear steps are formable between the input shaft and the output shaft through the planetary gear sets by selectively engaging shift elements of the plurality of shift elements. An actuating element of one of the plurality of shift elements is arranged, at least partially, radially within an element of the spur gear drive or the flexible traction drive mechanism arranged coaxially to the input shaft, and together with the spur gear drive or the flexible traction drive mechanism in a plane orthogonal to an axis of rotation of the input shaft.

Claims

1. A transmission (G) for a motor vehicle, comprising: an input shaft (GW1); an output shaft (GW2); a plurality of planetary gear sets (P1, P2, P3); a plurality of shift elements (A, B, C, D, E); and an electric machine (EM) arranged axially parallel to the input shaft (GW1) and operatively connected to the input shaft (GW1) with a constant transmission ratio via a spur gear drive (STG) or a flexible traction drive mechanism, wherein various gear ratios are formable between the input shaft (GW1) and the output shaft (GW2) through the planetary gear sets (P1, P2, P3) by selectively engaging shift elements of the plurality of shift elements (A, B, C, D, E), wherein an actuating element (BK) of one of the plurality of shift elements (B) is arranged, at least partially, radially within an element (STG1) of the spur gear drive (STG) or the flexible traction drive mechanism arranged coaxially to the input shaft (GW1), and together with the spur gear drive (STG) or the flexible traction drive mechanism in a plane (E1) is oriented at a right angle with respect to an axis of rotation of the input shaft (GW1).

2. The transmission (G) of claim 1, wherein the actuating element (BK) is a hydraulically operated piston.

3. The transmission (G) of claim 2, wherein a supply of hydraulic fluid for pressurizing the piston and a supply of hydraulic fluid for lubricating the spur gear drive (STG) or the flexible traction drive mechanism are supplied via separate ducts which are arranged, partially, within the input shaft (GW1).

4. The transmission (G) of claim 1, further comprising an interface (GA) to a transmission-external drive unit at one end of the transmission (G), the interface (GA) transmitting a turning motion of the transmission-external drive unit to the input shaft (GW1), wherein the spur gear drive (STG) or the flexible traction drive mechanism is arranged at an end of the transmission (G) positioned opposite the interface (GA) to the transmission-external drive unit.

5. A drive train for a motor vehicle, comprising the transmission (G) of claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) One exemplary embodiment of the invention is described in detail in the following with reference to the attached figures. In the figures, the following is shown:

(2) FIG. 1 shows a schematic view of a transmission in accordance with aspects of the present subject matter;

(3) FIG. 2 shows a partial, perspective view of one area of the transmission shown in FIG. 1 in accordance with aspects of the present subject matter; and

(4) FIG. 3 shows a drive train for a motor vehicle having a transmission in accordance with aspects of the present subject matter.

DETAILED DESCRIPTION

(5) 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.

(6) FIG. 1 shows a schematic view of a transmission G which comprises an input shaft GW1, an output shaft GW2, a first planetary gear set P1, a second planetary gear set P2, a third planetary gear set P3, five shift elements A, B, C, D, E, an electric machine EM, a torsional vibration damper TS, a connecting shaft AN, and a separating clutch K0.

(7) The first, second, and third planetary gear sets P1, P2, P3 are arranged coaxially to the input shaft GW1. The output shaft GW2 is permanently connected to the carrier of the first planetary gear set P1 and to the ring gear of the third planetary gear set P3. The ring gear of the first planetary gear set P1 is permanently connected to the carrier of the second planetary gear set P2. The ring gear of the second planetary gear set P2 is permanently connected to the carrier of the third planetary gear set P3. The sun gear of the second planetary gear set P2 is permanently connected to the input shaft GW1. The sun gear of the first planetary gear set P1 is rotationally fixable with respect to a housing GG of the transmission G by engaging the first shift element A. The input shaft GW1 is connectable to the sun gear of the third planetary gear set P3 by engaging the second shift element B. By engaging the third shift element C, the sun gear of the third planetary gear set P3 is rotationally fixable to the housing GG of the transmission G. By engaging the fourth shift element D, the carrier of the third planetary gear set P3 is rotationally fixable to the housing GG of the transmission G. The input shaft GW1 is connectable to the carrier of the third planetary gear set P3 by engaging the fifth shift element E.

(8) The first, second, third, and fifth shift elements A, B, C and E are force-locking shift elements, for example, while the fourth shift element D is a form-fit shift element, for example.

(9) The transmission G includes an interface GA to a transmission-external drive unit which is, for example, an internal combustion engine. The interface GA is configured for transmitting a rotational speed of the transmission-external drive unit to the input shaft GW1. A torsional vibration damper TS and a separating clutch K0 are arranged between the interface GA and the input shaft GW1. By engaging the separating clutch K0, the input shaft GW1 is connectable to a connecting shaft AN, on which the interface GA is arranged.

(10) The output shaft GW2 has, on one end, a spur gear tooth system which is utilized for the power transmission between the output shaft GW2 and a differential gear AG (not represented) arranged axially parallel to the output shaft GW2. The differential gear AG can be an integral part of the transmission G.

(11) The electric machine EM comprises a stator, which is rotationally fixed with respect to the housing GG, and a rotary rotor, and is arranged axially parallel to the input shaft GW1. The rotor is permanently operatively connected to the input shaft GW1 via a spur gear drive STG. In the represented exemplary embodiment, the spur gear drive STG includes an intermediate gear which is rotatably mounted on the housing GG. This intermediate gear intermeshes with an element STG1 of the spur gear drive STG, which is arranged coaxially to the input shaft GW1. An actuating element BK for actuating the shift element B is arranged radially within the element STG1 in this case. Integral parts of the spur gear drive STG as well as the actuating element BK are arranged in a plane E1 which is oriented normal to or at a right angle to the input shaft axis. Alternative to the spur gear drive STG, a flexible traction drive mechanism is also usable, for example, a chain drive.

(12) FIG. 2 shows a partial, perspective view of the transmission G according to the first exemplary embodiment represented in FIG. 1.

(13) FIG. 3 schematically shows a drive train of a motor vehicle having the transmission G. An internal combustion engine VKM is connected via the torsional vibration damper TS to the connecting shaft AN of the transmission G. Alternatively, the internal combustion engine VKM could be connected via the torsional vibration damper TS directly to the input shaft GW1 of the transmission G. The drive train could even contain a hydrodynamic torque converter 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 even include a direct drive 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 operatively 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.

(14) 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

(15) G transmission GG housing GW1 input shaft GW2 output shaft EM electric machine P1 first planetary gear set P2 second planetary gear set P3 third planetary gear set A first shift element B second shift element C third shift element D fourth shift element E fifth shift element BK actuating element STG spur gear drive STG1 element of the spur gear drive E1 plane GA interface K0 separating clutch TS torsional vibration damper AN connecting shaft VKM internal combustion engine AG differential gear DW driving wheel