DE102019119953A1 - Drive device for a motor vehicle with a first planetary gear carrier connected in a rotationally fixed manner on the second sun gear and a second planetary gear carrier connected in a rotationally fixed manner on the first sun gear - 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 first planetary gear carrier (8a) rotatably connected to the second sun gear (9b) and the second planetary gear carrier ( 8b) is rotatably connected to the first sun gear (9a).

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.

Also shows the DE 10 2004 024 086 A1 a drive device for motor vehicles with a drive unit that acts on two output shafts via a differential gear, with a device being provided on the output shafts with the interposition of at least one superposition gear, by means of which the output torque can be shifted from one output shaft to the other output shaft. To provide a drive device that is particularly effective in terms of control technology and function, it is proposed that the device be formed by at least one electric machine that can be switched as an electric motor and as a generator.

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.

This object is achieved according to the invention in a generic device in that the first planetary gear carrier is connected to the second sun gear in a rotationally fixed manner and the second planetary gear carrier is connected to the first sun gear in a rotationally fixed manner.

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 for torque transmission can be directly connected to one another, or that further transmission elements are located between two transmission elements for torque transmission, for example one shaft or several 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.

In a preferred embodiment, the first planetary gear carrier and the second sun gear can be operatively connected to the drive shaft, preferably via the first clutch. Alternatively, it is also conceivable that the first planet carrier and the second sun gear are operatively connected to the differential stage via the first clutch.

In addition, it can be expedient if the second planetary gear carrier and the first sun gear are operatively connected to the differential stage directly or via the second clutch or are fixed in a stationary / stationary / rotationally fixed manner in a housing.

According to an advantageous development, the first ring gear can be connected to the drive shaft in a rotationally fixed manner or can be operatively connected via the second clutch.

It is also conceivable that the second ring gear can be fixed in place in the housing. There is also the possibility that the second ring gear is operatively connected to the differential stage.

The drive device according to the invention thus allows great flexibility in the design of the gear structure, which makes it easier to adapt the desired gear ratio and spread without unnecessarily complicating the gear structure.

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, it being possible for a torque transmission device (reduction gear) to be 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, wherein at least one of the two output shafts is 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 a sun-carrier double bond. 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 a 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, whereby the basic structure of the gearbox has a sun-carrier double bond. In a first possible coaxial or axially parallel configuration with a switching element arranged on the input side, a moderate gear ratio can be achieved with a moderate spread. Optionally, an additional spur gear stage, for example designed as a spur gear differential, can be placed both upstream and downstream, which in turn increases the translation that can be implemented. A second coaxial or axially parallel configuration with a switching element on the input side and an optional upstream or downstream spur gear stage enables a low gear ratio with a moderate spread. Here, too, the translation can be increased by possibly adjusting the spur gear stage before or after. A third coaxial or axially parallel configuration with a switching element on the output side and an optional, upstream or downstream spur gear stage enables a moderate gear ratio with a high spread.

• 1 eine erste Ausführungsform einer erfindungsgemäßen Antriebsvorrichtung in koaxialer 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 zweite Ausführungsform einer erfindungsgemäßen Antriebsvorrichtung in koaxialer Bauweise,
• 6 eine erste Modifikation der Antriebsvorrichtung gemäß der zweiten Ausführungsform in achsparalleler Bauweise,
• 7 eine zweite Modifikation der Antriebsvorrichtung gemäß der zweiten Ausführungsform in koaxialer Bauweise,
• 8 eine dritte Ausführungsform einer erfindungsgemäßen Antriebsvorrichtung in koaxialer Bauweise,
• 9 eine erste Modifikation der Antriebsvorrichtung gemäß der dritten Ausführungsform in achsparalleler Bauweise, und
• 10 eine zweite Modifikation der Antriebsvorrichtung gemäß der dritten 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 a drive device according to the invention in a coaxial design,
• 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 second embodiment of a drive device according to the invention in a coaxial design,
• 6 a first modification of the drive device according to the second embodiment in an axially parallel construction,
• 7th a second modification of the drive device according to the second embodiment in a coaxial design,
• 8th a third embodiment of a drive device according to the invention in a coaxial design,
• 9 a first modification of the drive device according to the third embodiment in an axially parallel construction, and
• 10 a second modification of the drive device according to the third 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. Closing 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 and the second sun gear connected to it in a rotationally fixed manner 9b over the first clutch 12a or the first ring gear 10a via the second clutch 12b rotatably with the drive shaft 2 are connected, whereby in turn the first or second gear ratio can be implemented.

As described above, is in the drive device 1 according to the first embodiment, the first planet carrier 8a rotatably with the second sun gear 9b connected. In addition, the second planet carrier is 8b rotatably with the first sun gear 9a connected. The second ring gear 10b is stationary / non-rotatable / stationary in one housing 15th fixed / added / arranged and thus supports the gear assembly in the housing 15th from.

The output side is the non-rotatable assembly of the second planet carrier 8b and the first sun gear 9a with the differential stage 6 actively connected and thus directs the torque of the electric drive machine to the differential stage 6 which it is on the two output shafts 13a , 13b distributed. Here is the differential stage 6 in the first embodiment designed as a spur gear differential.

2 to 4th 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.

At the in 2 illustrated, first modification of the drive device 1 according to the first embodiment is the differential stage 6 designed as an additional planetary gear stage. A planetary gear carrier designed as a double planet is fixed against rotation with the second planetary gear carrier 8b connected. Two planetary gear sets are mounted on the double planet and each stand with one on the output shafts 13a , 13b trained sun gears in mesh.

The second modification of the first embodiment is shown in FIG 3 shown. As can be seen, there is an additional reduction gear configured as a spur gear on the output side 14th in the torque flow from the electric drive machine to the output shafts 13a , 13b between the second planetary gear 5 , in the first embodiment the non-rotatable connection between the first sun gear 9a and the second planet carrier 8b , and the differential stage 6 arranged.

Due to the reduction gear arranged on the output side 14th has the drive device 1 According to the second modification of the first embodiment, an axially parallel basic structure / construction, ie the drive shaft 2 is radially offset to the two output shafts 13a , 13b arranged.

As in 4th can be seen in the third modification of the drive device 1 according to the first embodiment, the reduction gear 14th on the input side between the electric drive machine and the transmission device 3 , especially the drive shaft 2 , interposed and designed as a spur gear stage.

5 shows a second embodiment of the drive device according to the invention 1 in coaxial design. The main differences to the one in 1 illustrated drive device 1 received.

In the drive device 1 according to the second embodiment is the double clutch device 11 Arranged on the input side and optionally connects via the first coupling 12a or the second clutch 12b the first planet carrier 8a and the second sun gear 9b or the first ring gear 10a with the drive shaft 2 . The first sun gear 9a rotates with the second planet carrier 8b connected and stationary in the housing 15th set, ie the transmission device 3 is based on the first sun gear 9a and the second planet carrier 8b in the case 15th from. The second ring gear 10b is in the second embodiment with the differential stage 6 operatively connected, so that the torque output from the transmission device 3 to the differential stage 6 via the second ring gear 10b he follows.

In the 6 and 7th are each a first and second modification of the drive device 1 shown according to the second embodiment. In the first modification of the second embodiment, the driving device is 1 Executed axially parallel and has the output side between the second ring gear 10b and the differential stage 6 arranged reduction gears 14th on. The drive device 1 according to the second modification of the second embodiment, in turn, is designed coaxially, the reduction gear 14th on the input side between the electric drive machine and the drive shaft 2 is interposed.

8th shows a third embodiment of the drive device according to the invention 1 in coaxial 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 double clutch device 11 arranged on the output side. The input shaft is the drive shaft 2 thus (directly) non-rotatably with the first ring gear 10a connected, so that the torque is introduced into the transmission device 3 always via the first ring gear 10a takes place and with the double clutch device 11 the torque output to the differential stage 6 can be varied.

The first planet carrier 8a rotates with the second sun gear 9b connected and can also use the first coupling 12a with the differential stage 6 be effectively connected. The second planet carrier 8b rotates with the first sun gear 9a connected and can in turn via the second coupling 12b with the differential stage 6 be effectively connected. Consequently, in the first gear ratio, the torque is generated from the first planetary gear carrier via the non-rotatable assembly 8a and the second sun gear 9b to the differential stage 6 forwarded and in the second gear ratio via the non-rotatable composite of the second planet carrier 8b and the first sun gear 9a .

Furthermore is in the drive device 1 according to the third embodiment, the second ring gear 10b stationary in the housing 15th arranged, ie the transmission device 3 is supported by the second ring gear 10b in the case 15th from.

In the 9 and 10 are each a first and second modification of the drive device 1 shown according to the third embodiment. In the first modification of the third embodiment, the driving device is 1 Executed axially parallel and has the output side between the double clutch device 11 and the differential stage 6 arranged reduction gears 14th on. The drive device 1 according to the second modification of the third embodiment is again carried out coaxially, the reduction gear 14th on the input side between the electric drive machine and the drive shaft 2 is interposed.

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]
• DE 102004024086 A1 [0003]

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 shiftable clutch (12a, 12b), characterized in that the first planetary gear carrier (8a) rotatably with the second sun gear (9b) and the second Planet carrier (8b) is rotatably connected to the first sun gear (9a). Drive device (1) after Claim 1 , characterized in that the first planet carrier (8a) and the second sun gear (9b) can be effectively connected to the drive shaft (2) or to the differential stage (6). Drive device (1) after Claim 1 or 2 , characterized in that the second planet carrier (8b) and the first sun gear (9a) can be effectively connected to the differential stage (6) or are fixed in a fixed position in a housing (15). Drive device (1) according to one of the Claims 1 to 3 , characterized in that the first ring gear (10a) can be actively connected to the drive shaft (2). 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) or is operatively connected to the differential stage (6). Drive device (1) according to one of the Claims 1 to 5 , characterized in that an additional reduction gear (14) is arranged in the torque flow between the electric drive machine and the differential stage (6). Drive device (1) after Claim 6 , characterized in that the reduction gear (14) is arranged between the electric drive machine and the first planetary gear set (4). Drive device (1) after Claim 6 , characterized in that the reduction gear (14) is arranged between the second planetary gear stage (5) and the differential stage (6). 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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