DE102009028384A1 - Device for distributing torque of internal combustion engine between wheels of driven vehicle axle for vehicle drive train, has shafts coupled with adjusting device that adjusts differential speed between another three shafts - Google Patents

Abstract

The device (5) has a shaft (8) operatively connected with a drive engine (2), and another shaft and a third shaft (9, 10) operatively coupled with wheels (6, 7) of driven vehicle axle (4). The former shaft is operatively connected with the latter and the third shafts by fourth, fifth and sixth shafts (11-13) of a differential drive (14). The fifth and sixth shafts are coupled with an adjusting device (16) that adjusts torque of the drive engine for adjusting differential speed between the latter, third and the fourth shafts.

Description

The The invention relates to a device for distributing a torque a drive machine in the vehicle transverse direction according to the im Preamble of claim 1 further defined type.

Out known in practice devices for distributing a torque a drive machine in the vehicle transverse direction between wheels of a drivable vehicle axle or known from practice transfer case for the transverse distribution of the drive torque of a drive machine a drive axle, which is preferably the vehicle's rear axle, usually include constructively elaborate Transmission devices and cooperating actuating gear and adjusting devices. The total weight of such transverse transfer cases, by means of which a drive torque with defined degrees of distribution between the wheels of the both sides of the drive axle is distributable, is approx. 15 to 20 kg higher than the conventionally designed axle differentials.

Of Further are the so-called torque vectoring transverse distributor gears due to occurring in the area of the adjusting devices respectively Towing losses and in the field of transmission equipment in Operating occurring splash losses compared to differential gear devices, which are performed without torque vectoring functionality, but with a reduced efficiency operated.

In addition is the space requirement of the torque vectoring cross transfer gearbox higher than that of conventional executed Differential gear units without corresponding torque vectoring functionality.

Of the Present invention is therefore the object of a space-saving and characterized by a low weight device for Distributing a torque of an engine in the vehicle transverse direction between wheels To provide a drivable vehicle axle, which with high Efficiency is operable.

According to the invention this Task with a device having the features of claim 1 solved.

at the device according to the invention for distributing a torque of an engine in the vehicle transverse direction between wheels a drivable vehicle axle is a first shaft with the prime mover can be brought into operative connection. additionally is the first shaft each with at least one wheel of a vehicle side the drivable vehicle axle can be brought into operative connection shafts coupled.

According to the invention the first wave over at least three waves comprehensive superposition gear with at least one of the further shafts of the device in operative connection, wherein a shaft of the superposition gear is coupled with a device via which to set a Differential speed between the second shaft and the third shaft the device a torque available adjustable and introduced into the superposition gearing is.

The Torque vectoring functionality The device according to the invention is a structurally simple Design displayable, whereby the device for distributing a torque a drive machine in the vehicle transverse direction between wheels of a drivable vehicle axle both by a small space requirement as well as being characterized by a low total weight.

There in the range of the device according to the invention a torque vectoring functionality without additional Setting device is displayed, the device is compared to known from practice Torque Vectoring cross distributor gears with a higher efficiency operable, since a drag loss affecting efficiency does not occur.

at an advantageous embodiment the device according to the invention is connected to the device shaft of the superposition gear via a Switching element with a shaft of the device rotatably connected, which especially during a straight ahead in the area of the facility energy recuperable or additionally Driving energy in a vehicle driveline in the field of drivable Vehicle axle is introduced, for example, a boost operation or the like.

The Device is in a further advantageous embodiment the device according to the invention designed as an electric machine, the motor and preferably can also be operated as a generator. Depending on the respective present However, there is also the possibility that the device a hydraulic or pneumatic machine or another suitable one Drive is.

Further advantages and advantageous embodiments of the subject invention emerge from the patent claims and embodiments described below with reference to the drawing, wherein in the description of the various embodiments in favor of Clarity for construction and functionally identical components the same reference numerals are used.

It shows:

1 a highly schematic representation of a vehicle drive train, which is formed in the region of a drivable vehicle axle with a first embodiment of the device according to the invention;

2 a 1 corresponding representation of a trained with a second embodiment of the device according to the invention vehicle drive train;

3 a simplified single view of a running as Plusplanetenradsatz superposition gearing of the device according to the invention 2 ;

4 a 1 corresponding representation of a formed with a third embodiment of the device according to the invention vehicle drive train; and

5 a 4 corresponding representation of a trained with a fourth embodiment of the device according to the invention vehicle drive train.

1 shows a highly simplified representation of a vehicle drive train 1 with an engine running as an internal combustion engine 2 , with a gearbox device operatively connected therewith 3 and a drivable vehicle axle 4 in whose area a device 5 for distributing a torque of the prime mover 2 in the vehicle transverse direction between wheels 6 . 7 is arranged.

A first wave 8th the device 5 is present on the gearbox device 3 with the prime mover 2 be brought into operative connection, wherein the first wave 8th when not shown in detail in the drawing vehicle drive trains, in which the prime mover is designed, for example, as an electric machine, can also be connected directly to the drive machine when the vehicle drive train is formed without manual transmission device.

The first wave 8th is with two more waves 9 . 10 the device 5 coupled, each with the wheel 6 or the wheel 7 a vehicle side of the drivable vehicle axle 4 in a manner known per se in operative connection. Between the first wave 8th and the third wave 10 the device 5 is a three waves 11 . 12 and 13 comprehensive superposition gearbox 14 arranged, which is designed as a high translational wave gear. The superposition gear is presently designed with a translation greater than 15 and can in other embodiments of the device according to the invention 5 Depending on the particular application case have translations greater than 50 or translations in a preferred range of translation between 50 and 200.

A first wave 11 of the superposition gearbox 14 in this case represents a ring gear, which via a gear designed as bevel gear 15 with the first wave 8th the device 5 connected is. In addition, the first wave 11 of the superposition gearbox 14 non-rotatable with the second shaft 9 the device 5 coupled. One with the first wave 11 of the superposition gearbox 14 at least partially engaged second shaft 12 as one with a footbridge 19 rotatably connected elastic ring is formed with an external toothing, is rotatably connected to the third shaft 10 the device 5 connected and combs in a conventional manner with a sun gear designed as a third wave 13 of the superposition gearbox 14 , in turn, with a facility 16 is actively connected.

The device 16 is presently designed as an electrical machine, wherein the third wave 13 of the superposition gearbox 14 rotatably with a rotor 16A the electric machine 16 is connected and a stator 16B the device 16 is fixed on the housing side. About the device 16 is to set a differential speed between the second shaft 12 and the third wave 13 the device 5 a torque available and in the area of the third shaft 13 of the superposition gearbox 14 into this introductory.

The device 5 replaces both a conventional differential formed without torque vectoring functionality and a torque vectoring cross transfer gear, wherein the device 5 Compared to the latter transverse distribution gears has a smaller space requirement and a lower dead weight. Is from the institution 16 no torque in the superposition gearbox 14 initiated, behaves the vehicle axle 4 like a rigid axle. A speed compensation between a curve-internal wheel 6 respectively. 7 and an outside wheel 7 respectively. 6 the vehicle axle 4 is initiated by appropriate introduction of a torque from the device 16 in the superposition gearbox 14 set. The control device stands for it with appropriate sensors of the vehicle (steering angle, yaw rate, etc.) z. B. via a data bus (CAN) in conjunction to set the required differential speed.

About a present as frictional Kupp ment executed switching element 17 about which the second wave 12 and the third wave 13 of the superposition gearbox 14 are rotatably connected to each other, is one in the motorized operation of the electric machine 16 generated drive torque as the drive torque for the vehicle powertrain 1 executed vehicle can be introduced without being between the wheels 6 and 7 a differential speed is generated. Furthermore, when the switching element is closed 17 during a regenerative operation of the electric machine 16 and preferably during a straight-ahead travel of the vehicle, the possibility to recuperate energy or braking energy in the region of the electric machine and to charge an electrical storage medium or to supply a vehicle electrical system without a differential rotational speed between the wheels 6 and 7 to effect.

2 shows one 1 corresponding representation of a vehicle drive train 1 that of a second embodiment of the device 5 is formed and otherwise essentially the same in the description 1 described vehicle powertrain 1 corresponds, which is why in the following description essentially only addresses the differences and with respect to the further functionality of the vehicle drive train 1 according to 2 to the description 1 is referenced.

The device 5 of the vehicle drive train 1 according to 2 is with a trained as plus planetary gear superposition gear 14 executed, the stationary gear ratio, for example, may be equal to 2 and may also have other translations depending on the particular application. The differential gear superposition gearbox 14 points in the area of the second wave 12 double planet 18 on, with outer planet gears 18A with the first shaft designed as a ring gear 11 and inner planet gears 18B with the third wave running as a sun gear 13 of the superposition gearbox 14 comb. A power flow is in each case between the drive machine 2 and the wheels 6 and 7 the drivable vehicle axle 4 over the transmission 15 , the first wave 11 of the superposition gearbox 14 , the double planets 18 and the planetary bridge 19 on which the double planets 18 are rotatably mounted, and the sun gear 13 produced.

The outer planet wheels 18A in turn form with other planetary gears 20 a present without ring gear planetary gear set 21 Double planetary gears, with the other planet gears 20 with another sun wheel 22 comb, which in the embodiment shown smaller than the sun 13 of the superposition gearbox 14 is executed. Depending on the particular application, there is also the possibility of the other planetary gears 20 of the planetary gear set 21 with the inner planet wheels 18B of the superposition gearbox 14 to pair. The further sun wheel 22 of the planetary gear set 21 is non-rotatable with the rotor 16A the device 16 coupled while the stator 16B is executed fixed to the housing.

Depending on the particular operating state of the device 16 or the electric machine 16 is about the planetary gear set 21 a correspondingly converted torque in the region of the outer planet gears 18A in the superposition gearbox 14 and thus in the power flow of the vehicle drive train 1 initiated in the same way as with the device 5 according to 1 a degree of distribution of that of the prime mover 2 provided torque between the wheels 6 and 7 to be able to change according to requirements and to provide a desired driving behavior.

Due to the additional planetary gear set 21 has the device 5 in case of a defect of the electric machine 16 the same mode of action as an open differential, while in the active state of the electric machine 16 different degrees of locking in the area of the device 5 or the drivable vehicle axle 4 operating state dependent adjustable. The preferably frictional switching element 17 is to bridge the adjustment of the device 5 provided, wherein in the closed operating state of the switching element 17 the device 16 to produce a hybrid operating mode without generating a speed difference between the wheels is usable, in which case either braking energy is recuperated or a device-side drive torque in the vehicle drive train 1 can be introduced.

The speed of the device 16 is much lower than the speed of the wheels 6 and 7 while influencing the degree of distribution of the torque of the prime mover 2 between the wheels 6 and 7 Provide when the planet gears 18A or 18B of the superposition gearbox 14 via a preferably without ring gear planetary gear with higher stationary gear ratio than that of the superposition gear 14 is driven.

A vehicle powertrain 1 that of a third embodiment of the device 5 is executed, in which the outer planet gears 18A of the superposition gearbox 14 via a highly translating harmonic drive 23 with the planetary gear set 21 are connected shows 4 , Alternatively, there is also the possibility that the inner tarpaulin tenräder 18B over the wave gear 23 with the planetary gear set 21 are coupled.

The superposition gearbox 14 the device 5 according to 4 has essentially the same structure as the superposition gear 14 the device 5 according to 2 and 3 on and the planet footbridge 19 the second wave 12 of the superposition gearbox 14 is non-rotatable with a designed as a bridge with flexible ring shaft 24 of the corrugated transmission 23 connected. A trained as a sun gear second wave 25 of the corrugated transmission 23 is non-rotatable with the other planetary gears 20 of the planetary gear set 21 connected while a ring designed as a ring gear 26 of the corrugated transmission 23 rotatably with the outer planetary gears 18A of the superposition gearbox 14 is actively connected.

The designed as a ring gear first wave 11 of the superposition gearbox 14 is rotatable on the second shaft 9 the device 5 stored while the bridge 19 having second wave 12 of the superposition gearbox 14 non-rotatable with the second shaft 9 the device 5 connected and on the second wave 12 of the superposition gearbox 14 opposite side of running as a sun gear third wave 13 of the superposition gearbox 14 rotatable on the third shaft 10 the device 5 is stored.

The wave gear 23 is not self-locking and designed to rotate the outer planetary gears 18A of the superposition gearbox 14 intended. Because the wave gear 23 over the planetary gear set 21 with the device 16 is in operative connection, the axis rotation is partially compensated and does not need of the device 16 be compensated.

Alternatively to the in 4 illustrated embodiment of the device 5 There is also the possibility of running as a sun gear third wave 13 of the superposition gearbox 14 over the wave gear 23 with the device 16 to couple and the third wave 13 opposite to the planet carrier 19 executed second wave 12 of the superposition gearbox 14 to twist, the degree of distribution of the drive torque of the prime mover 2 between the wheels 6 and 7 Depending on the operating state can vary and represent a desired driving behavior.

At the in 4 illustrated embodiment of the device 5 In addition, there is the possibility of the stator 16B the device 16 either on the housing side or as under the reference number 161B shown rotatably with the planet carrier 12 of the superposition gearbox 14 to couple, in the latter embodiment of the device 5 the stator 161B during a straight ahead one with the vehicle driveline 1 according to 4 running vehicle with the wheel speed has to rotate, but this is a control effort compared to the housing-fixed design of the stator 16B elevated.

To illustrate the hybrid operation of the device 16 are the other sun wheel 22 of the planetary gear set 21 and the planet carrier 12 of the superposition gearbox 14 over the switching element 17 rotatably connected.

Instead of the device 16 on a rotating shaft of the device 5 to be fixed or the rotor 16A To run with shaft speed, the superposition of the corrugated transmission 23 via a stationary superposition drive, for example by a cogging torque in the area of the device 16 is feasible in the interpretation of the translation of the planetary gear set 21 be taken into account, wherein the stationary gear ratio of the planetary gear 21 preferably not equal to 2.

An in 5 shown vehicle drive train 1 comprises a fourth embodiment of the device 5 , which is a further education of in 4 illustrated third embodiment of the device 5 represents. In the device 5 according to 5 is between the institution 16 and the planetary gear set 21 another as a Plusplanetenradsatz executed double planetary gear 27 provided, with the other sun gear 22 of the planetary gear set 21 rotatable with a first sun gear 28 of the double planetary gear set 27 connected is. The first sun wheel 28 of the double planetary gear set 27 in the present case is smaller than the other sun gear 22 of the planetary gear set 21 designed and larger than a second sun gear 29 of the double planetary gear set 27 executed. The first sun wheel 28 and the second sun wheel 29 comb each with double planet wheels 30 that rotates on the planet carrier 19 of the superposition gearbox 14 and the corrugated transmission 23 are arranged.

In a first switching position S1 of the switching element 17 is the first shaft designed as a ring gear 11 of the superposition gearbox 14 rotatable with the device 16 connected while the device 16 in a second switching position S2 of the switching element 17 with the second sun gear of the double planetary gear set 27 is coupled. In the first switching position S1 of the switching element 17 is about the device 5 a hybrid operation can be displayed and in the area of the facility 16 Energy recuperable or the drive torque of the prime mover 2 a device-side drive torque superimposed. In the second switching position S2 of the switching element 17 is one in the area of the facility 16 generated torque in the superposition gearbox 14 Introduced to the degree of distribution of the drive torque of the prime mover 2 between the wheels 6 and 7 or the waves 9 and 10 the device 5 Depending on the operating condition can vary and each requested driving behavior with the vehicle powertrain 1 be made available running vehicle.

In a third switching position S3 of the switching element 17 , which corresponds in principle to a neutral position, is the device 16 neither with the first shaft designed as a ring gear 11 of the superposition gearbox 14 still with the second sun gear 29 of the double planetary gear set 27 connected and from the power flow of the vehicle drive train 1 decoupled.

In a further embodiment of the device not shown in detail in the drawing 5 is the superposition gear as a high translational Wolfromgetriebe with a translation greater than 15, preferably with a translation of 50 to 200, designed to provide the above-described functionality with low space requirement, low weight and structurally simple means available.

LIST OF REFERENCE NUMBERS

1

Vehicle powertrain

2

prime mover

3

gear change means

4

drivable vehicle axle

5

contraption

6 7

wheel

8th

first Wave of the device

9

second Wave of the device

10

third Wave of the device

11

first Shaft of the superposition gearbox

12

second Shaft of the superposition gearbox

13

third Shaft of the superposition gearbox

14

Superposition gear

15

transmission

16

Facility

16A

rotor

16B

stator

161B

stator

17

switching element

18

double Planet

18A

outer planetary gear

18B

inner planet

19

planet spider

20

additional planet

21

planetary gear

22

additional sun

23

The wave gear

24

first Shaft of the wave gear

25

second Shaft of the wave gear

26

third Shaft of the wave gear

27

Another double planetary

28

first Sun wheel of the double planetary gear set

29

second Sun wheel of the double planetary gear set

30

double Planet

S1 to S3

switch position of the switching element

Claims (11)

Contraption ( 5 ) for distributing a torque of a prime mover ( 2 ) in the vehicle transverse direction between wheels ( 6 . 7 ) a drivable vehicle axle ( 4 ) with one with the prime mover ( 2 ) operable first wave ( 8th ), each with at least one wheel ( 6 . 7 ) a vehicle side of the drivable vehicle axle can be brought into operative connection shafts ( 9 . 10 ), characterized in that the first wave ( 8th ) of the device ( 5 ) over at least three waves ( 11 to 13 ) comprehensive superposition gearing ( 14 ) with at least one of the further waves ( 9 . 10 ) of the device ( 5 ) is in operative connection, wherein a wave ( 12 or 13 ) of the superposition gearing ( 14 ) with a device ( 16 ) for adjusting a differential speed between the second shaft ( 9 . 11 ) and the third wave ( 10 ) of the device ( 5 ) a torque available and in the superposition gearing ( 14 ) can be introduced. Device according to claim 1, characterized in that the device ( 16 ) connected wave ( 12 or 13 ) of the superposition gearing ( 14 ) via a switching element ( 17 ) with a wave ( 10 ) of the device ( 5 ) is rotatably connected. Device according to claim 1 or 2, characterized in that the device ( 16 ) is designed as an electric machine, which is operable by a motor and preferably also by a generator. Device according to one of claims 1 to 3, characterized in that the superposition gear ( 14 ) via a planetary gear set ( 21 ) with the device ( 16 ) connected is. Apparatus according to claim 4, characterized in that the operative connection between the planetary gear set ( 21 ) and the superposition gearing ( 14 ) a wave gear ( 23 ) having. Device according to claim 5, characterized in that between the planetary gear set ( 21 ) and the institution ( 16 ) a double planetary gear set ( 27 ) with double planets ( 30 ) and two separate sun gears ( 28 . 29 ) is provided. Device according to one of claims 1 to 6, characterized in that a translation of the superposition gearing ( 14 ) is greater than 15. Device according to one of claims 1 to 7, characterized in that the superposition gear ( 14 ) is designed as a high-ratio transmission, preferably with a ratio of 50 to 200. Device according to one of claims 1 to 8, characterized in that the superposition gear ( 14 ) as a plus planetary gear set with double planets ( 18 ) is executed. Apparatus according to claim 9, characterized in that the superposition gearing ( 14 ) is a wave gear, wherein a designed as a ring gear first wave ( 11 ) of the wave gear ( 14 ) with a wheel ( 6 ) is coupled to a vehicle side, while designed as a flexible ring second wave ( 12 ) connected to the ring gear ( 11 ) is at least partially engaged, with a wheel ( 7 ) can be brought into operative connection with the other side of the vehicle and a third shaft designed as a sun gear ( 13 ) of the wave gear ( 14 ) with the device ( 16 ) connected is. Device according to one of claims 1 to 8, characterized that the superposition gearbox a tungsten gear is.

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