DE102019119955A1 - Drive device for a motor vehicle with sun gear-planetary gear carrier and / or sun gear-ring gear binding - Google Patents

Abstract

A drive device (1) for a motor vehicle has an electric drive machine which is operatively connected to a transmission device (3) via a drive shaft (2), the transmission device (3) having at least one first and second planetary gear stage (4, 5) and a differential stage (6), the first planetary gear set (4) having a first planetary gear set with several planetary gears (7a), the planetary gears (7a) of the first planetary gear set being rotatably arranged on a first planetary gear carrier (8a) and with a first sun gear (9a) as well as meshing with a first ring gear (10a), the second planetary gear set (5) having a second planetary gear set with several planet gears (7b), the planet gears (7b) of the second planetary gear set being rotatably arranged on a second planetary gear carrier (8b) and with a second sun gear (9b) and with a second ring gear (10b) are in meshing engagement, the first and the z wide planetary gear stage (4, 5) are operatively connected to a double clutch device (11) with a first and a second power shiftable clutch (12a, 12b), and the planetary gear carrier (8a, 8b) of one planetary gear stage (4, 5) rotatably connected to the sun gear (9a, 9b) of the other planetary gear set (4, 5) is connected.

Description

The invention relates to a drive device for a motor vehicle, in particular for an electrically driven motor vehicle, with an electric drive machine which is operatively connected to a transmission device via a drive shaft, the transmission device having at least a first and second planetary gear stage and a differential stage, the first planetary gear stage having a having first planetary gear set with several planetary gears, wherein the planetary gears of the first planetary gear set are rotatably arranged on a first planetary gear carrier and are in meshing engagement with a first sun gear and with a first ring gear, the second planetary gear set having a second planetary gear set with several planetary gears, the planetary gears of the second planetary gear set are rotatably arranged on a second planet carrier and are in meshing engagement with a second sun gear and a second ring gear, the first and the second Planetary gear stage are operatively connected to a double clutch device with a first and a second power shiftable clutch.

Drive devices for motor vehicles are already known from the prior art. For example shows DE 10 2011 088 668 A1 a drive device with at least one electric drive machine, with at least one first planetary drive with a clutch and with a differential. A rotor shaft of the drive machine is coupled non-rotatably to a first connection shaft of the planetary drive formed from at least three connection shafts. A second connecting shaft of the first planetary drive can be fixed in a rotationally fixed manner against a component of the drive device by means of a shift sleeve of the clutch. A third connection shaft of the first planetary drive is operatively connected to a sum shaft of the differential. The shift sleeve can be shifted into positive engagement either with the second connection shaft of the first planetary drive or in a torque-transmitting operative connection with the sum shaft of the differential.

However, the prior art has the disadvantage that, due to a complex gear structure, a large number of different parts and components are installed and therefore the production costs increase and assembly is made more difficult.

It is therefore the object of the invention to avoid or at least alleviate the disadvantages of the prior art. In particular, a drive device for a motor vehicle is to be further developed, the focus being on the simplest possible transmission structure with many identical parts and a suitable gear ratio distribution or spread.

In a device of the generic type, this object is achieved according to the invention in that the planetary gear carrier of one planetary gear set is non-rotatably connected to the sun gear of the other planetary gear set.

The drive device according to the invention for a motor vehicle comprises an electric drive machine which is operatively connected to a transmission device via a drive shaft.

The transmission device has at least a first and second planetary gear set as well as a differential stage, the first planetary gear set having a first planetary gear set with several planet gears, the planet gears of the first planetary gear set being rotatably arranged on a first planetary gear carrier and with a first sun gear and a first ring gear The second planetary gear set has a second planetary gear set with a plurality of planetary gears, the planetary gears of the second planetary gear set are rotatably arranged on a second planetary gear carrier and mesh with a second sun gear and a second ring gear, and the first and second planetary gear sets are operatively connected to a double clutch device with a first and a second power shiftable clutch.

The term “operatively connected” means that two transmission elements can be directly connected to one another, or that further transmission elements are located between two transmission elements, for example one or more shafts or gears. Two gearwheels that are in meshing engagement with one another are provided for transmitting a torque and a speed from one gearwheel to the other gearwheel. A gear is to be understood as meaning, for example, a sun gear, a ring gear and a planet gear of a planetary gear set.

A double clutch device is to be understood as a device with two power shift clutches. Furthermore, the term “power shiftable clutch” is to be understood as a device which has at least one open and one closed state and can be switched between the at least two states under load. When open, the clutch does not transmit any torque.

Advantageous embodiments are claimed in the subclaims and are explained in more detail below.

The first planetary gear carrier can preferably be connected to the second sun gear in a rotationally fixed manner. In addition, it is conceivable that the second planet carrier is additionally or alternatively connected to the first sun gear in a rotationally fixed manner. In other words, according to the invention, the first planetary gear carrier can be connected non-rotatably to the second sun gear and / or the second planetary gear carrier can be non-rotatably connected to the first sun gear.

In addition, it can be expedient if the first sun gear is fixed in a stationary / stationary manner in a housing. The second ring gear can also be fixed in a stationary manner in the housing.

In a preferred embodiment, the first planetary gear carrier can be connected non-rotatably to the drive shaft via the first clutch. Furthermore, the first ring gear can be connected non-rotatably to the drive shaft via the second clutch.

According to the invention, the first ring gear can be connected non-rotatably to the second sun gear.

Furthermore, an advantageous embodiment can also be characterized in that an additional reduction gear is arranged in the torque flow between the electric drive machine and the differential stage. The reduction gear can be arranged on the input side between the electric drive machine and the first planetary gear stage or on the output side between the second planetary gear stage and the differential stage. The additional reduction gear increases the spread of the transmission device and can be designed, for example, as a spur gear stage or as a further planetary gear stage.

The first and second clutch of the double clutch device can preferably be designed as a friction clutch. Furthermore, the two couplings can preferably be arranged coaxially to one another. In particular, the respective clutch can be actuated by a respective actuator in order to initiate opening or closing of the respective clutch. The actuator can be implemented hydraulically, electromechanically, electromagnetically or, for example, also pneumatically.

It is useful here if opening both clutches can realize a power cut-off at the same time. Closing the first clutch and opening the second clutch can realize a first gear ratio, whereas closing the second clutch and opening the first clutch can realize a second gear ratio. In order to ensure that the shifting process from one clutch to the other clutch is largely free of tractive effort, one clutch can open in a transitional period while the other is closing. Via the slip in the clutches, designed as friction clutches, a torque-free switchover between two gear stages can take place, which can be perceived by the operator of the drive device as a switchover mode between two gear stages without traction, which in turn increases the switching comfort for the operator of the drive device. The first gear ratio is preferably not the same as the second gear ratio. For example, the first gear ratio can be greater than the second gear ratio. Alternatively, the first gear ratio can be smaller than the second gear ratio.

Furthermore, the electric drive machine preferably has a stator and a rotor, the rotor being non-rotatably connected to the drive shaft. The drive shaft can be designed as a rotor shaft or there is an axial offset between the drive shaft and the rotor shaft, a torque transmission device (gear) being arranged between the two shafts.

Furthermore, the differential stage is preferably designed as a spur gear differential, the differential stage being provided to distribute a drive power of the drive machine to a first and a second output shaft.

The drive machine can be arranged coaxially or axially parallel to the differential stage. The drive shaft is preferably arranged coaxially to the two output shafts. In particular, the drive shaft is designed as a hollow shaft, at least one of the two output shafts being guided axially through the drive shaft. The two output shafts are preferably arranged on a common drive axle. Alternatively, the drive shaft is arranged axially parallel to the two output shafts, axially parallel means that there is an axial offset between the drive shaft and the output shafts.

In other words, the invention relates to a two-speed transmission for electric axles with power sharing. In the search for transmissions for two gears with an advantageous gear ratio distribution in an axially parallel and coaxial arrangement, the aim is to provide the simplest possible gear structure with many identical parts and suitable gear ratio distribution or spreading through a combination of two planetary gear stages with a spur gear stage and a shifting element designed as a double clutch or synchro unit the basic structure of the transmission is a sun gear-planet carrier or a sun gear-ring gear connection having. In a first possible axially parallel or coaxial configuration, the switching element is arranged on the input side, which in the coaxial case ensures a moderate gear ratio with a moderate spread and in the axially parallel case a high gear ratio with a moderate spread. Optionally, an additional spur gear stage, designed, for example, as a spur gear differential, can be placed both upstream and downstream. A second and a third axially parallel configuration with a switching element on the input side and an optional spur gear stage enable a high gear ratio with a moderate spread. A fourth coaxial configuration with a switching element on the input side ensures a low gear ratio with a moderate spread, this arrangement also enabling a high gear ratio with a moderate spread for the case of an axially parallel alignment with a front or rear spur gear stage.

• 1 eine erste Ausführungsform der erfindungsgemäßen Antriebsvorrichtung in achsparalleler Bauweise,
• 2 eine erste Modifikation der Antriebsvorrichtung gemäß der ersten Ausführungsform in koaxialer Bauweise,
• 3 eine zweite Modifikation der Antriebsvorrichtung gemäß der ersten Ausführungsform in achsparalleler Bauweise,
• 4 eine dritte Modifikation der Antriebsvorrichtung gemäß der ersten Ausführungsform in koaxialer Bauweise,
• 5 eine vierte Modifikation der Antriebsvorrichtung gemäß der ersten Ausführungsform in koaxialer Bauweise,
• 6 eine zweite Ausführungsform der erfindungsgemäßen Antriebsvorrichtung in achsparalleler Bauweise,
• 7 eine erste Modifikation der Antriebsvorrichtung gemäß der zweiten Ausführungsform in koaxialer Bauweise,
• 8 eine zweite Modifikation der Antriebsvorrichtung gemäß der zweiten Ausführungsform in koaxialer Bauweise,
• 9 eine dritte Ausführungsform der erfindungsgemäßen Antriebsvorrichtung in achsparalleler Bauweise,
• 10 eine erste Modifikation der Antriebsvorrichtung gemäß der dritten Ausführungsform in koaxialer Bauweise,
• 11 eine vierte Ausführungsform der erfindungsgemäßen Antriebsvorrichtung in koaxialer Bauweise,
• 12 eine erste Modifikation der Antriebsvorrichtung gemäß der vierten Ausführungsform in achsparalleler Bauweise, und
• 13 eine zweite Modifikation der Antriebsvorrichtung gemäß der vierten Ausführungsform in koaxialer Bauweise.

Further measures improving the invention are shown in more detail below together with the description of preferred embodiments of the invention with reference to the figures. The figures each show a simplified schematic representation to illustrate the structure of drive devices according to the invention. Show it:

• 1 a first embodiment of the drive device according to the invention in an axially parallel construction,
• 2 a first modification of the drive device according to the first embodiment in a coaxial design,
• 3 a second modification of the drive device according to the first embodiment in an axially parallel construction,
• 4th a third modification of the drive device according to the first embodiment in a coaxial design,
• 5 a fourth modification of the drive device according to the first embodiment in a coaxial design,
• 6 a second embodiment of the drive device according to the invention in an axially parallel design,
• 7th a first modification of the drive device according to the second embodiment in a coaxial design,
• 8th a second modification of the drive device according to the second embodiment in a coaxial design,
• 9 a third embodiment of the drive device according to the invention in an axially parallel construction,
• 10 a first modification of the drive device according to the third embodiment in a coaxial design,
• 11 a fourth embodiment of the drive device according to the invention in a coaxial design,
• 12th a first modification of the drive device according to the fourth embodiment in an axially parallel construction, and
• 13 a second modification of the drive device according to the fourth embodiment in a coaxial construction.

The figures are merely of a schematic nature and are used exclusively for understanding the invention. The same elements are provided with the same reference symbols. The features of the individual embodiments can be interchanged.

1 shows a first embodiment of the drive device according to the invention 1 in coaxial design.

The drive device according to the invention 1 for a motor vehicle - not shown here - has an electric drive machine - not shown here - and a transmission device 3 on. The electric drive machine has a stator and a rotor. A drive power (torque) of the electric drive machine is generated via a drive shaft 2 between the electric drive machine and the transmission device 3 is arranged and designed as a rotor shaft, in the transmission device 3 initiated.

The transmission device 3 comprises a first and second planetary gear set 4th , 5 as well as a differential stage 6 . The first planetary gear stage 4th has a first planetary gear set with several planetary gears 7a on which rotatable on a first planet carrier 8a are arranged and with a first sun gear 9a as well as with a first ring gear 10a are in mesh. So the planet gears mesh 7a of the first planetary gear set radially between the first sun gear 9a and the first ring gear 10a . The second planetary gear stage 5 has a second planetary gear set with several planetary gears 7b on which rotatable on a second planet carrier 8b are arranged and with a second sun gear 9b as well as with a second ring gear 10b are in mesh. So the planet gears mesh 7b of the second planetary gear set radially between the second sun gear 9b and the second ring gear 10b .

There is also a double clutch device 11 with a first clutch 12a and a second clutch 12b intended. Lock in the first clutch 12a and opening the second clutch 12b realizes a first gear ratio, with a closing of the second clutch 12b and opening the first clutch 12a realized a second gear ratio. The first gear ratio is not the same as the second gear ratio. By opening both clutches 12a , 12b a power shutdown is implemented.

In other words, by shifting the dual clutch device 11 optionally that from the electric drive machine via the transmission device 3 on the differential stage 6 transmitted torque can be varied between the first and the second gear ratio. The torque thus transmitted is ultimately used by the differential stage 6 on output shafts 13a , 13b which are connected, for example, to drive wheels of the motor vehicle. The transmission device 3 thus essentially enables two-speed operation of the motor vehicle.

In the drive device 1 according to the first embodiment is the double clutch device 11 on the input side of the transmission device 3 arranged. In particular, depending on the shifting of the double clutch device 11 optionally the first planet carrier 8a or the first ring gear 10a rotatably with the drive shaft 2 are connected and thus the first or second gear ratio can be implemented.

The first planet carrier 8a is, as described above, on the one hand rotatably fixed to the first clutch 12a connected, but also with the second sun gear in the first embodiment 9b non-rotatably connected. Furthermore is the first sun gear 9a stationary (fixed to the housing) in a housing 15th arranged.

The planet gears 7b the second planetary gear stage 5 mesh radially between the one with the first planet carrier 8a non-rotatably connected, second sun gear 9b and the stationary in the housing 15th arranged, second ring gear 10b . The second planet carrier 8b is with the differential stage 6 operatively connected and directs the torque of the electric drive machine to the differential stage 6 further, which this in turn on the two output shafts 13a , 13b distributed.

2 to 5 show modifications of the drive device according to the invention 1 according to the first embodiment. Only the differences to the one in 1 illustrated drive device 1 received according to the first embodiment.

In the 2 The first modification shown is a drive device 1 in a coaxial design. The differential stage is 6 explicitly designed as an additional double planetary gear stage. The torque is from the second planet carrier 8b transferred to a double planet that is non-rotatably connected to this, which in turn is connected to the output shafts 13a , 13b trained sun gears in meshing double planetary gears transmits and so the output shafts 13a , 13b drives.

3 Fig. 3 shows a second modification of the drive device 1 in axially parallel design. This is in the torque flow from the electric drive machine to the output shafts 13a , 13b between the second planet carrier 8b and the differential stage 6 an additional reduction gear 14th interposed. According to the second modification, this is a speed reducer 14th designed as a spur gear and increases the spread of the transmission device 3 .

At the in 4th The illustrated third modification of the first embodiment is the reduction gear 14th on the input side between the electric drive machine and the transmission device 3 , especially the drive shaft 2 , interposed. In contrast to the in 3 illustrated drive device 1 The drive shaft is in an axially parallel design 2 coaxial to the two output shafts 13a , 13b arranged.

5 again shows a fourth modification of the first embodiment in which the reduction gear 14th as with the in 4th shown, third modification, on the input side between the electric drive machine and the transmission device 3 is arranged. In addition, the fourth modification is the differential stage 6 designed as a double planetary gear stage, in which the torque from the second planetary gear carrier 8b onto a double planetary connected in a rotationally fixed manner and finally via the double planetary gears onto the output shafts 13a , 13b is transmitted. The fourth modification can consequently be understood as a combination of the first and third modification.

6 shows a second embodiment of the drive device according to the invention 1 in axially parallel design. Only the differences to the one in 1 illustrated drive device 1 received.

In the drive device 1 according to the second embodiment is the first clutch 12a the double clutch device arranged on the input side 11 non-rotatably with the first planet carrier 8a connected and the second clutch 12b is non-rotatably with the first ring gear 10a connected, so that by optionally opening or closing the first clutch 12a or the second clutch 12b the two gear ratios can be realized.

The first ring gear 10a is also non-rotatable with the second sun gear 9b connected. Further is the first sun gear 9a non-rotatably with the second planet carrier 8b connected and via the between the second planetary gear 5 and the differential stage 6 intermediate reduction gear 14th with the differential stage 6 effectively connected. The second ring gear 10b is stationary in the housing in the second embodiment 15th recorded.

7th and 8th show modifications of the drive device according to the invention 1 according to the second embodiment. Only the differences to the one in 6 illustrated drive device 1 received according to the first embodiment.

In the 7th The illustrated first modification of the second embodiment is a drive device 1 in a coaxial design. The reduction gear 14th on the input side between the electric drive machine and the transmission device 3 , especially the drive shaft 2 , interposed.

8th Fig. 3 shows a second modification of the drive device 1 according to the second embodiment in a coaxial design. Here is the differential stage 6 explicitly designed as an additional double planetary gear stage. The torque is from the second planet carrier 8b or the first sun gear connected to it in a rotationally fixed manner 9a transmitted to a double planetary connected to it in a rotationally fixed manner, which in turn transmits the torque to the output shafts 13a , 13b trained sun gears in meshing double planetary gears transmits and so the output shafts 13a , 13b drives.

9 shows a third embodiment of the drive device according to the invention 1 in axially parallel design. Only the differences to the one in 1 illustrated drive device 1 received.

In the drive device 1 according to the third embodiment is the first clutch 12a the double clutch device arranged on the input side 11 non-rotatably with the first planet carrier 8a connected and the second clutch 12b is non-rotatably with the first ring gear 10a connected, so that by optionally opening or closing the first clutch 12a or the second clutch 12b the two gear ratios can be realized.

The first ring gear 10a is also non-rotatable with the second sun gear 9b connected. Further is the first sun gear 9a non-rotatably with the second planet carrier 8b connected and stationary with this in the housing 15th set. The second ring gear 10b is about that between the second planetary gear 5 and the differential stage 6 intermediate reduction gear 14th with the differential stage 6 operatively connected, so that the torque on the output side via the second ring gear 10b and the reduction gear 14th on the differential stage 6 and transferred from this to the output shafts 13a , 13b is distributed.

10 Fig. 10 shows a first modification of the drive device 1 according to the third embodiment in a coaxial design. Here is the reduction gear 14th on the input side between the electric drive machine and the transmission device 3 interposed and designed as a spur gear stage. In contrast to the in 9 illustrated drive device 1 The drive shaft is in an axially parallel design 2 coaxial to the two output shafts 13a , 13b arranged.

In 11 is a fourth embodiment of the drive device according to the invention 1 shown in coaxial design. Only the differences to the one in 1 illustrated drive device 1 received.

In the drive device 1 according to the fourth embodiment is the first clutch 12a the double clutch device arranged on the input side 11 non-rotatably with the first planet carrier 8a connected and the second clutch 12b is non-rotatably with the first ring gear 10a connected, so that by optionally opening or closing the first clutch 12a or the second clutch 12b the two gear ratios can be realized.

The first planet carrier 8a rotates with the second sun gear 9b connected. Further is the first sun gear 9a non-rotatably with the second planet carrier 8b connected and stationary with this in the housing 15th set. The second ring gear 10b is about that between the second planetary gear 5 and the differential stage 6 intermediate reduction gear 14th with the differential stage 6 operatively connected, so that the torque on the output side via the second ring gear 10b and the reduction gear 14th on the differential stage 6 and transferred from this to the output shafts 13a , 13b is distributed.

12th Fig. 10 shows a first modification of the drive device 1 according to the fourth embodiment in an axially parallel construction. This is in the torque flow from the electric drive machine to the output shafts 13a , 13b between the second ring gear 10b and the differential stage 6 the reduction gear designed as a spur gear stage 14th interposed.

In 13 is a second modification of the drive device 1 according to the fourth embodiment shown in a coaxial construction. Here is the reduction gear 14th on the input side between the electric drive machine and the transmission device 3 interposed. Furthermore, the output shafts 13a , 13b coaxial with the drive shaft 2 arranged.

List of reference symbols

1

Drive device

2

drive shaft

3

Transmission device

4th

first planetary gear stage

5

second planetary gear stage

6th

Differential stage

7a

first planet gear (s)

7b

second planet gear (s)

8a

first planet carrier

8b

second planet carrier

9a

first sun gear

9b

second sun gear

10a

first ring gear

10b

second ring gear

11

Double clutch device

12a

first clutch

12b

second clutch

13a, 13b

Output shaft

14th

Reduction gear

15th

casing

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was 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.

Patent literature cited

• DE 102011088668 A1 [0002]

Claims (10)

Drive device (1) for a motor vehicle, comprising an electric drive machine which is operatively connected to a transmission device (3) via a drive shaft (2), the transmission device (3) having at least a first and second planetary gear stage (4, 5) and a differential stage ( 6), the first planetary gear set (4) having a first planetary gear set with several planetary gears (7a), the planetary gears (7a) of the first planetary gear set being rotatably arranged on a first planetary gear carrier (8a) and with a first sun gear (9a) and are in meshing engagement with a first ring gear (10a), the second planetary gear set (5) having a second planetary gear set with several planet gears (7b), the planet gears (7b) of the second planetary gear set being rotatably arranged on a second planetary gear carrier (8b) and with a second sun gear (9b) and a second ring gear (10b) are in meshing engagement, the first and the second e planetary gear stage (4, 5) are operatively connected to a double clutch device (11) with a first and a second power shift clutch (12a, 12b), characterized in that the planetary gear carrier (8a, 8b) of one planetary gear stage (4, 5) rotatably with the sun gear (9a, 9b) of the other planetary gear set (4, 5) is connected. Drive device (1) after Claim 1 , characterized in that the first planet carrier (8a) is rotatably connected to the second sun gear (9b). Drive device (1) according to one of the Claims 1 or 2 , characterized in that the second planet carrier (8b) is rotatably connected to the first sun gear (9a). Drive device (1) according to one of the Claims 1 to 3 , characterized in that the first sun gear (9a) is fixed in a stationary manner in a housing (15). Drive device (1) according to one of the Claims 1 to 4th , characterized in that the second ring gear (10b) is fixed in place in the housing (15). Drive device (1) according to one of the Claims 1 to 5 , characterized in that the first planet carrier (8a) can be connected non-rotatably to the drive shaft (2) via the first coupling (12a). Drive device (1) according to one of the Claims 1 to 6 , characterized in that the first ring gear (10a) can be connected to the drive shaft (2) in a rotationally fixed manner via the second clutch (12b). Drive device (1) according to one of the Claims 1 to 7th , characterized in that the first ring gear (10a) is non-rotatably connected to the second sun gear (9b). Drive device (1) according to one of the preceding claims, characterized in that the drive machine is arranged coaxially to the differential stage (6). Drive device (1) according to one of the preceding claims, characterized in that the drive machine is arranged offset axially parallel to the differential stage (6).

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