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CN-116348324-B - Transmission for a motor vehicle, motor vehicle drive train having a transmission, and method for operating a transmission

CN116348324BCN 116348324 BCN116348324 BCN 116348324BCN-116348324-B

Abstract

The invention relates to a transmission (4) comprising an electric machine (30), a first input shaft (10), a second input shaft (11) and a countershaft (12). A first spur gear stage (20) is provided, which has a fixed gear (23) which is arranged on the first input shaft (10) and a movable gear (24) which meshes therewith and is rotatably mounted on the auxiliary shaft (12) and can be fixed to the auxiliary shaft (12) by means of a first switching element (S2), and a second spur gear stage (19) is provided, which has a fixed gear (26) which is arranged on the second input shaft (11) and a movable gear (25) which meshes therewith and is rotatably mounted on the auxiliary shaft (12) and can be fixed to the auxiliary shaft (12) by means of a second switching element (S4). Furthermore, the movable gear (24) of the first spur gear stage (20) and the movable gear (25) of the second spur gear stage (19) are connected to each other in a rotationally fixed manner by means of a third switching element (S3). Furthermore, a planetary stage (31) is provided, the second element (35) of which is connected to the second input shaft (11) in a rotationally fixed manner and the third element (36) of which is coupled to the rotor (32) of the electric machine (30), the first element (34) of the planetary stage (31) being fixable by actuation of the fourth switching element (B) and the two elements (34, 35, 36) of the planetary stage (31) being connected to one another in a rotationally fixed manner by closing the fifth switching element (K).

Inventors

  • F. Coulter
  • P. Zimmer
  • J. Pavlakevic
  • I. Pufan Kuheng
  • S. BAKER
  • M. BREMER
  • M. HORN
  • O. Bayer
  • J. Kartenbach
  • T. MARTIN
  • M Wei Kesi
  • T crow
  • M. BACHMANN

Assignees

  • 采埃孚股份公司

Dates

Publication Date
20260505
Application Date
20211215
Priority Date
20201218

Claims (13)

  1. 1. A transmission for a motor vehicle, comprising an electric machine (30), a first input shaft (10), a second input shaft (11) and a countershaft (12), which countershaft (12) is permanently connected with an output side (14), a first spur gear stage (20) is provided, which has a fixed gear (23) arranged on the first input shaft (10) and a movable gear meshing with the fixed gear, which is rotatably supported on the countershaft (12) and can be fixed on the countershaft (12) by means of a first switching element (S2), a second spur gear stage (19) is also provided, which has a fixed gear (26) arranged on the second input shaft (11) and a movable gear meshing with the fixed gear, which is rotatably supported on the countershaft (12) and can be fixed on the countershaft (12) by means of a second switching element (S4), and which movable gear of the first spur gear stage (20) and the movable gear of the second spur gear stage (19) can be fixed on the countershaft (12) by means of a third switching element (S3) and can be non-rotatable with respect to one another, in the form of a second planetary gear stage (35), a second planetary gear stage (37) and a carrier (37) are provided, which is in the form of rotation-resistant to one another, the second element (35) is connected in a rotationally fixed manner to the second input shaft (11) and the third element (36) is coupled to the rotor (32) of the electric machine (30), the first element (34) of the planetary stage (31) can be fixed by actuating the fourth switching element (B) and two of the elements (34, 35, 36) of the planetary stage (31) can be connected in a rotationally fixed manner to one another by closing the fifth switching element (K), the planetary stage (31) is arranged axially with the fifth switching element (K) at the level of the electric machine (30) and radially inside the electric machine, and the first input shaft (10) and the second input shaft (11) are arranged coaxially to a drive shaft (9) for connecting the transmission to a drive machine of the motor vehicle, the drive shaft (9) can be connected in a rotationally fixed manner to the first input shaft (10) by means of the first switching clutch (K1) and can be connected in a rotationally fixed manner to the second input shaft (11) and axially overlapping the first input shaft (11) and the second input shaft (11) respectively axially as a first input shaft (11) and a second input shaft (11) which axially overlaps.
  2. 2. Transmission according to claim 1, characterized in that a third spur gear stage (18) with a fixed gear (21) and a movable gear (22) and a sixth switching element (S1) are also provided, which, when operated, fixes the movable gear (22) of the third spur gear stage (18) and in this case couples the first input shaft (10) and the countershaft (12) to one another.
  3. 3. The transmission of claim 2, wherein the transmission comprises a gear, By closing the sixth switching element (S1) a first gear (G1) is formed between the first input shaft (10) and the output side (14) by the force flow via the third spur gear stage (18), By actuating the first switching element (S2) to form a second gear (G2) between the first input shaft (10) and the output side (14) under the force flow via the first spur gear stage (20), -Forming a third gear position (G3) between the second input shaft (11) and the output side (14) by closing the third switching element (S3) and the sixth switching element (S1) under force flow guidance via the second spur gear stage (19), the first spur gear stage (20) and the third spur gear stage (18), and -In the first variant (G4.1) by operating the second switching element (S4) and in the second variant (G4.2) by closing the first switching element (S2) and the third switching element (S3), respectively, a fourth gear is formed between the second input shaft (11) and the output side (14) under the force flow conduction via the second spur gear stage (19).
  4. 4. A transmission according to any one of claims 1 to 3, characterised in that a braking device (41) is also provided, which is coupled to the drive shaft (9).
  5. 5. Transmission according to claim 4, characterized in that the braking device (41) is arranged offset to the axis of the drive shaft (9) and is coupled to the drive shaft by a gear stage (42).
  6. 6. A transmission according to claim 4, characterized in that the braking device (41) is arranged coaxially with the drive shaft (9) and is connected in a rotationally fixed manner thereto.
  7. 7. A transmission according to any one of claims 1 to 3, characterised in that the electric machine (30) is arranged coaxially to the second input shaft (11), and the rotor (32) is connected in a rotationally fixed manner to the third element (36) of the planetary stage (31).
  8. 8. A transmission according to any one of claims 1 to 3, wherein each shift element is embodied as a form-locking shift element.
  9. 9. A transmission according to any one of claims 1 to 3, characterized in that the countershaft (12) and the output side (14) are coupled by a spur gear stage (15).
  10. 10. Motor vehicle drive train (1), characterized in that it comprises a transmission according to any one of claims 1 to 9.
  11. 11. Motor vehicle drive train (1) according to claim 10, characterized in that it is a motor vehicle drive train for a hybrid or electric vehicle.
  12. 12. Method for operating a transmission according to any of claims 1 to 9, characterized in that, in order to achieve a charging operation or a starting operation, the second switching clutch (K2) is closed and the fourth switching element (B) or the fifth switching element (K) is operated.
  13. 13. Method for operating a transmission according to any of claims 1 to 9, characterized in that, in order to achieve a charging operation or a starting operation, the first switching clutch (K1) is closed and the third switching element (S3) and the fourth switching element (B) or the third switching element (S3) and the fifth switching element (K) are operated.

Description

Transmission for a motor vehicle, motor vehicle drive train having a transmission, and method for operating a transmission Technical Field The invention relates to a transmission for a motor vehicle, comprising an electric machine, a first input shaft, a second input shaft and a countershaft, which is permanently connected to the output side, a first spur gear stage having a fixed gear arranged on the first input shaft and a movable gear meshing with the fixed gear, which is rotatably mounted on the countershaft and can be fixed on the countershaft by means of a first switching element, and a second spur gear stage having a fixed gear arranged on the second input shaft and a movable gear meshing with the fixed gear, which is rotatably mounted on the countershaft and can be fixed on the countershaft by means of a second switching element, and the movable gear of the first spur gear stage and the movable gear of the second spur gear stage being connected to each other by means of a third switching element in a rotationally fixed manner. The invention further relates to a motor vehicle drive train having the aforementioned transmission and to a method for operating the transmission. Background In motor vehicles, a multi-speed transmission is known in which a plurality of different gear ratios as gears can be shifted by actuating a corresponding shift element, which is preferably done automatically. The transmission is used to suitably achieve a traction force supply of the motor vehicle drive machine according to different criteria. In transmissions for hybrid vehicles, the above-described transmissions are often also combined with one or more electric machines, which can be engaged in the transmission in different ways to achieve different operating modes, such as electric-only driving. DE 10 2013 211 591 A1 discloses a transmission having a first input shaft and a second input shaft that are coaxial to one another. By actuating the associated switching element, each input shaft can be connected in a rotationally fixed manner to a shaft which is arranged coaxially to the input shaft and is connected in a rotationally fixed manner to the rotor of the electric motor. Furthermore, two countershafts are provided, which are parallel to each other and also to the input shaft axis. The transmission comprises spur gear stages which each consist of a fixed gear and a movable gear which meshes with the respective fixed gear. The spur gear stage fixed gears are each arranged on one of the input shafts in a rotationally fixed manner, while the associated movable gear is each rotatably mounted on one of the countershafts and can be fixed there by an associated shift element. Furthermore, two movable gears which are rotatably mounted axially next to one another on a countershaft can be connected to one another in a rotationally fixed manner by a shift element. Disclosure of Invention On the basis of the prior art described above, the object of the present invention is now to provide a transmission in which a high number of gears can be shifted in a compact configuration, and in which the electric machine is connected in a suitable manner. This object is achieved by a transmission, a motor vehicle drive train and a method for operating a transmission. According to the invention, the transmission comprises an electric machine, a first input shaft, a second input shaft and a countershaft, which countershaft is permanently connected with the output side. A first spur gear stage is provided, which has a fixed gear wheel arranged on the first input shaft and a movable gear wheel which meshes with the fixed gear wheel and is rotatably mounted on the auxiliary shaft and can be fixed to the auxiliary shaft by means of a first switching element. A second spur gear stage is also provided, which has a fixed gear wheel arranged on the second input shaft and a movable gear wheel meshing with the fixed gear wheel, which is rotatably supported on the auxiliary shaft and can be fixed thereto by means of a second switching element. The movable gear wheel of the first spur gear stage and the movable gear wheel of the second spur gear stage are connected to one another in a rotationally fixed manner by a third switching element. A "shaft" is understood in the sense of the present invention to be a rotatable component of a transmission, by means of which a force flow can be conducted between the components if necessary with simultaneous operation of the respective shift elements. The respective shafts may connect the components to each other in the axial or radial direction or in both the axial and radial directions. The respective shaft can thus also be an intermediate piece, by means of which the respective components are connected, for example radially. "Axial" in the sense of the present invention means an orientation in the direction of the longitudinal centre axis of the transmission, the rotation axis of the shaft of the transmission be