DE102019119946B3 - Drive device for a motor vehicle with a non-rotatable ring gear-planet carrier double bond - 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) 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 wherein the first planetary gear carrier (8a) rotatably with the second ring gear (10b) and the second planetary gear carrier ( 8b) is rotatably connected to the first ring gear (10a).

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 mesh 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 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 2006 028 798 A1 a double clutch transmission for a front-transverse arrangement with a double clutch and two sub-transmissions, the two clutches of the double clutch each acting on a coaxial transmission input shaft that acts on a sub-transmission, in which the sub-transmissions are designed as positive-locking planetary gears, with the output takes place on the same side of the transmission as the drive and axially parallel to the drive with the same direction of rotation and the torque is transmitted to the output shaft via at least one intermediate shaft arranged parallel to the transmission input shafts.

The DE 10 2012 017 352 A1 shows a drive device for an electrically driven axle of a motor vehicle, with a driving electric machine, a transmission gear and a differential that drives via output shafts to the driven wheels of the motor vehicle, the transmission gear being formed by two planetary gears coupled to one another, which are split into two via two switching elements Gear ratios are switchable, wherein the driven element of the epicyclic gear is the sun gear of the first epicyclic gear and the output element is the web of the first epicyclic gear, that furthermore the web of the first epicyclic gear is coupled to the ring gear of the second epicyclic gear and that the ring gear of the first epicyclic gear is coupled to the Web of the second epicyclic gear is connected, wherein the one switching element with the web and the other switching element is drivingly connected to the sun gear of the second planetary gear.

The DE 10 2016 202 727 A1 shows an epicyclic gear transmission, with: a power input, a power output, a partial epicyclic gear, which is driven by the power input and whose translation effect can be changed by specifying gear members, with a first sun gear, a first planetary set, a first planet carrier and a first ring gear, Load stage with a fixed gear ratio, which is driven through an output of the epicyclic gearbox and forms the power output of the epicyclic gearbox, with a load stage sun gear, a load stage planetary set, a load stage planet carrier and a load stage ring gear, and a braking device with a first brake for the selective definition of a first rotating component of the epicyclic gearbox, and a second brake for the selective fixing of a second rotating component of the epicyclic gear, the braking device on a side facing away from the load level of the epicyclic gear is arranged.

The U.S. 2,838,960 A shows a four-speed and reverse gear transmission for self-propelled vehicles, preferably for agricultural and industrial wheel tractors.

The object of the invention is to further develop a drive device for a motor vehicle, the focus being on a transmission structure that is as simple as possible with many identical parts and a suitable gear ratio distribution or spread.

This object is achieved according to the invention in a device of the generic type by the features of independent claims 1 and 2.

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 “load-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.

According to the solution according to the invention, the first sun gear can be connected to the drive shaft in a rotationally fixed manner or fixed in a stationary manner in a housing.

In addition, it is conceivable that the second sun gear can be connected non-rotatably to the drive shaft or operatively connected to the differential stage.

According to the invention, the first planetary gear carrier and the second ring gear connected to it in a rotationally fixed manner can be fixed in a stationary manner in the housing, in particular via the second clutch. It is also conceivable that the first planet carrier and the second ring gear connected to it in a rotationally fixed manner are operatively connected to the differential stage.

In the solution according to the invention, the second planet carrier and the first ring gear connected to it in a rotationally fixed manner can be operatively connected to the differential stage. Alternatively, the non-rotatable combination of the second planetary gear carrier and the first ring gear can also be fixed in a fixed position in the housing, preferably via the second clutch.

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 traction force interruption, one clutch can open in a transitional period while the other closes. 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.

In other words, the invention relates to a two-speed transmission for electric axles with a ring gear-planet carrier double bond. Looking for two-speed gearboxes with more advantageous Gear ratio distribution in an axially parallel and coaxial arrangement is to provide the simplest possible gear structure with many identical parts and a suitable gear ratio distribution or spread through a combination of two planetary gear stages with a spur gear stage and a shift element designed as a double clutch or synchro unit, with the basic structure of the transmission being a ring gear-planetary gear carrier double bond having. In a first possible axially parallel embodiment, the fixed shaft can optionally be changed via the switching element, which ensures 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 shift element on the output side and an optional upstream or downstream spur gear stage enables a moderate gear ratio with a moderate spread.

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

An advantageous embodiment provides 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 gear device and can be designed, for example, as a spur gear stage or as a further planetary gear stage.

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 (reduction 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. Alternatively, however, the differential stage can also be designed as a further planetary gear, in particular as a double planetary gear.

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.

• 1 eine erste nicht erfindungsgemäße Ausführungsform einer 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 zweite nicht erfindungsgemäße Ausführungsform einer in koaxialer Bauweise,
• 5 eine Modifikation der Antriebsvorrichtung gemäß der zweiten Ausführungsform in koaxialer Bauweise,
• 6 eine dritte erfindungsgemäße Ausführungsform einer Antriebsvorrichtung in koaxialer Bauweise,
• 7 eine Modifikation der Antriebsvorrichtung gemäß der dritten Ausführungsform in achsparalleler Bauweise,
• 8 eine vierte erfindungsgemäße Ausführungsform einer Antriebsvorrichtung in koaxialer Bauweise, und
• 9 eine Modifikation der Antriebsvorrichtung gemäß der vierten Ausführungsform in achsparalleler 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 the drive devices. Show it:

• 1 a first embodiment, not according to the invention, of a drive device 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 second embodiment, not according to the invention, of a coaxial design,
• 5 a modification of the drive device according to the second embodiment in a coaxial design,
• 6th a third embodiment according to the invention of a drive device in coaxial construction,
• 7th a modification of the drive device according to the third embodiment in an axially parallel construction,
• 8th a fourth embodiment according to the invention of a drive device in a coaxial design, and
• 9 a modification of the drive device according to the fourth embodiment in an axially parallel 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 not according to the invention 1 in coaxial design.

The drive device 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 6th . 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 6th transmitted torque can be varied between the first and the second gear ratio. The torque thus transmitted is ultimately used by the differential stage 6th 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 in the torque flow between the electric drive machine and the transmission device 3 an additional reduction gear 14th interposed. Here is the reduction gear 14th designed as a spur gear stage and thus increases the spread of the transmission device 3 .

Furthermore is in the drive device 1 according to the first embodiment, 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 via the first coupling 12a the first sun gear 9a or via the second coupling 12b the first planet carrier 8a non-rotatably (stationary) in a housing 15th be determined.

It is also in the drive device 1 according to the first embodiment, the first planet carrier 8a rotatably with the second ring gear 10b connected and the second planet carrier 8b rotatably with the first ring gear 10a connected. The non-rotatable combination of the second planet carrier 8b and the first ring gear 10a is again with the differential stage 6th effectively connected and so conducts it via the one with the second sun gear 9b non-rotatably connected drive shaft 2 introduced torque of the electric drive machine to the differential stage 6th which this ultimately to the output shafts 13a , 13b distributed.

2 and 3 show modifications of the drive device 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 2 is the differential stage 6th designed as a further planetary stage. In particular, the planetary stage is designed with a double planet on which two planetary gear sets are mounted. The two planetary gear sets are in meshing engagement with the two output shafts 13a , 13b trained sun gears and thus transmit the torque to the two output shafts 13a , 13b .

3 Fig. 3 shows a second modification of the drive device 1 according to the first embodiment in an axially parallel construction. The reduction gear designed as a spur gear stage is here 14th on the output side between the second planetary gear stage 5 , especially the second planet carrier 8b , and the differential stage 6th interposed.

4th shows a second embodiment of the drive device not according to the invention 1 in coaxial design. Only the differences to the one in 1 illustrated drive device 1 received according to the first embodiment.

In the drive device 1 according to the second embodiment is the first sun gear 9a rotatably with the drive shaft 2 connected and thus conducts the torque of the electric drive machine in the transmission device 3 a. The first planet carrier 8a and the second ring gear connected to it in a rotationally fixed manner 10b are with the differential stage 6th connected and transfer the torque to the output shafts 13a , 13b out. The first ring gear 10a is with the second planet carrier 8b non-rotatably connected and can use the second clutch 12b in the case 15th be determined. The first clutch 12a however, enables the second sun gear to be fixed fixed to the housing 9b .

In the 5 The illustrated modification of the second embodiment is a drive device 1 in a coaxial design. The differential stage is 6th designed as a further planetary stage. In particular, the planetary stage is designed with a double planet on which two planetary gear sets are mounted. The two planetary gear sets are in meshing engagement with the two output shafts 13a , 13b trained sun gears and thus transmit the torque to the two output shafts 13a , 13b . The double planet is rotatably fixed with the first planet carrier 8a and the second ring gear 10b connected. In particular, the double planet is in the axial direction of the output shafts 13a , 13b between the first planet carrier 8a and the second ring gear 10b inserted and welded to these.

6th 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 according to the first embodiment.

In the drive device 1 according to the third embodiment is the first sun gear 9a rotatably (stationary) in the housing 15th set. The second sun gear 9b in turn is rotationally fixed to the drive shaft 2 connected and forwards that of the electric drive machine via the reduction gear arranged on the input side 14th transmitted torque in the transmission device 3 a. The first planet carrier 8a and the second ring gear connected to it in a rotationally fixed manner 10b are about the second clutch 12b with the differential stage 6th operatively connected, whereas the second planet carrier 8b and the first ring gear connected to it in a rotationally fixed manner 10a over the first clutch 12a with the differential stage 6th are effectively connected. Thus, depending on the circuit of the double clutch device 11 the output of the torque to the differential stage 6th and the output shafts 13a , 13b optionally via the non-rotatable assembly of the first planet carrier 8a and the second ring gear 10b or the non-rotatable composite of the second planet carrier 8b and the first ring gear 10a respectively.

7th shows a modification of the drive device 1 according to the third embodiment in an axially parallel construction. The reduction gear designed as a spur gear stage is here 14th on the output side between the second planetary gear stage 5 , especially the second planet carrier 8b , and the differential stage 6th interposed.

8th shows a fourth 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 according to the first embodiment.

In the drive device 1 according to the fourth embodiment is the first sun gear 9a rotatably with the drive shaft 2 connected and forwards that of the electric drive machine via the reduction gear arranged on the input side 14th transmitted torque in the transmission device 3 a. The second sun gear 9b is with the differential stage 6th actively connected and directs the torque via this to the output shafts 13a , 13b . The first planet carrier 8a and the second ring gear connected to it in a rotationally fixed manner 10b can in the fourth embodiment via the first clutch 12a stationary in the housing 15th be determined. Via the second clutch 12b however, the second planet carrier can 8b and the first ring gear connected to it in a rotationally fixed manner 10a stationary in the housing 15th be determined.

9 shows a modification of the drive device 1 according to the third embodiment in an axially parallel construction. The reduction gear designed as a spur gear stage is here 14th on the output side between the second planetary gear stage 5 and the differential stage 6th 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

Claims (7)

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), the first planetary gear carrier (8a) in a rotationally fixed manner with the second ring gear (10b) and the second planetary gear carrier (8b) ) is non-rotatably connected to the first ring gear (10a), the first sun gear (9a) being fixed in a stationary manner in a housing (15), the second sun gear (9b) being non-rotatably connected to the drive shaft (2), the first planetary gear carrier (8a) and the second ring gear (10b) connected to it in a rotationally fixed manner are operatively connected to the differential stage (6) via the second clutch (12b), the second planet carrier (8b) and the first ring gear (10a) connected in a rotationally fixed manner to the differential stage ( 6) are operatively connected via the first clutch (12a). 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), the first planetary gear carrier (8a) in a rotationally fixed manner with the second ring gear (10b) and the second planetary gear carrier (8b) ) is non-rotatably connected to the first ring gear (10a), the first sun gear (9a) being non-rotatably connected to the drive shaft (2), the second sun gear (9b) being operatively connected to the differential stage (6), the first planetary gear carrier (8a) and the second ring gear (10b) connected to it in a rotationally fixed manner can be fixed in the housing (15), the second planet carrier (8b) and the first ring gear (10a) connected in a rotationally fixed manner being fixed in the housing (15). Drive device (1) according to one of the Claims 1 or 2 , 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 3 , 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 3 , 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 Claims 1 to 5 , characterized in that the drive machine is arranged offset axially parallel to the differential stage (6).

Images