WO2013034538A1 - Planetary gearing and drive train therewith - Google Patents

Abstract

The invention relates to a planetary gearing (4) with a sun gear (6) mounted rotatably about a central axis (12), with at least one first planet gear (7) which meshes with the sun gear (6) and meshes with a first ring gear (10) arranged coaxially with respect to the sun gear (6), and with at least one second planet gear (8) which meshes with a second ring gear (11) arranged coaxially with respect to the sun gear (6), wherein the first and the second planet gear (6, 7) are arranged rotatably on a common planet carrier (9) mounted rotatably about the central axis (12), wherein the first planet gear (7) meshes with the second planet gear (8). The planetary gearing (4) is blockable via a preferably wet-running, second release clutch (14).

Description

 PLANETARY TRANSMISSION AND DRIVE TRAVEL THEREFORE

The invention relates to a planetary gear with a rotatably mounted about a central axis sun gear, with at least one sun gear in meshing with the first planetary gear, which is arranged coaxially with the sun gear first ring gear meshing with at least one second planetary gear, which with a coaxial arranged to the sun gear second ring gear is in meshing engagement, wherein the first and the second planetary gear are rotatably mounted on a rotatably mounted about the central axis common planet carrier, wherein the first planet gear is in meshing with the second planet gear. Furthermore, the invention relates to a planetary gear having drive train for a vehicle.

Planetary gears are differentiated into plus and minus. Minus transmissions have at least one planet gear, which is arranged between sun gear and ring gear, wherein the direction of rotation of the ring gear is different from the direction of rotation of the sun gear. By contrast, positive transmissions, for example, achieve the same direction of rotation in the ring gear through a second planetary gear between the sun gear and the ring gear as with the sun gear.

The KR 2002-0 007 944 AI discloses a planetary gear with a driven sun gear, a first Platenrad and a second planetary gear, wherein the two planet gears are arranged on a common planet carrier. The first planet gear acts on a first ring gear and the second planet gear on a housing-fixed second ring gear. The ring gear is connected to a driven shaft.

EP 1 426 223 A2 describes a power-branching hybrid drive train with a planetary gear with two sun gears, a planet carrier and two ring gears, wherein between the one ring gear and a sun gear two groups of meshing planet gears are arranged. A ring gear can be braked by a braking device. The internal combustion engine acts on the other ring gear, one of two electric machines acts on a sun gear.

The object of the invention is to allow different translations in the simplest possible and space-saving manner.

According to the invention this is achieved in that the planetary gear is blockable via a preferably wet-running second clutch. In the locked mode of the planetary gear friction losses can be reduced, which has an advantageous effect on the efficiency. The blocking can be done by rigid coupling of any two elements of the planetary gear.

Preferably, it is provided that the second ring gear has a larger inner diameter than the first ring gear. It can be provided in particular that the axis of rotation of the second planetary gear is further spaced from the axis of rotation of the sun gear than the axis of rotation of the first planetary gear, wherein preferably the axis of rotation of the second planetary gear between the axis of rotation of the first planetary gear and the second ring gear is arranged.

The sun gear can be connected to a driving or driving off first shaft and the planet carrier with a driving off or driving second shaft. In this case, for example, the planet carrier can be made hollow and within the planet carrier the sun gear or connectable to the sun gear first shaft can be arranged.

The planetary gear according to the invention is particularly suitable for use in a drive train for a vehicle, in particular for a hybrid vehicle with an internal combustion engine and at least one electric machine. It can be provided that at least one ring gear rotatably mounted about the central axis, preferably the second ring gear, is drivingly connected to the electric machine, preferably this ring gear is fixedly connected to the rotor of the electric machine or formed integrally with the rotor of the electric machine ,

At least one ring gear rotatably mounted about the central axis, preferably the first ring gear, may be connected to a preferably wet-running brake. Thus, the first ring gear can be held.

The sun gear may be drivably connectable to a first shaft connected to an internal combustion engine via a preferably dry first clutch.

It is particularly advantageous if the planet carrier is rotatably connected via a preferably wet-running second clutch with the second ring gear. The second clutch thus makes it possible, if necessary, to connect or disconnect the planetary gear carrier, which is preferably connected via a gear intermediate stage with an abortive second shaft, to the second ring gear. In order to easily enable more than two gear ratios, it can be provided that an additional gearbox, preferably for two gear ratios, in the drive train - preferably between the engine and the planetary gear - is arranged.

The present drive concept represents a combination of power-split and parallel system. Due to the fact that the drive takes place on the one hand via a ring gear, on the other hand via the sun gear, a parallel drive mode can be realized with both drive machines. The internal combustion engine can act on the sun gear, the electric machine on a ring gear. Conversely, it is also possible to let the internal combustion engine act on a ring gear and the electric machine on a sun gear.

Compared to a purely power-split concept results in an improvement in efficiency, since the planetary gear rotates in a block and thus no rolling bearing losses occur and the driving moment does not need to be supported by another drive unit.

The invention will be explained in more detail below with reference to FIGS. They show schematically:

1 shows a drive train with a planetary gear according to the invention in a first embodiment;

2 shows the drive train with combined drive in first gear.

3 shows the drive train with combined drive in second gear.

4 shows the drive train with purely electric drive in first gear;

5 shows the drive train with purely electric drive in second gear.

6 shows the drive train with torque distribution in the first gear.

7 shows the drive train with torque distribution in second gear.

8 shows the drive train in recuperative operation in first gear;

9 shows the drive train in recuperative operation in the second gear.

10 shows a drive train with a planetary gear according to the invention in a second embodiment;

11 shows the drive train with purely electric drive in first gear; 12 shows the drive train with purely electric drive in second gear.

13 shows the drive train with internal combustion engine drive in first gear;

14 shows the drive train with internal combustion engine drive in the second gear.

15 shows the drive train in internal combustion engine drive in third gear. and

Fig. 16 shows the drive train in internal combustion engine drive in the third

 Corridor .

Functionally identical parts are provided in the embodiment variants with the same reference numerals.

Fig. 1 shows schematically a drive train 1 for a hybrid vehicle in a first embodiment with a driven by a not shown internal combustion engine first shaft 2 and a driven second shaft 3, wherein between the first and second shaft 2, 3, a planetary gear 4 is arranged. The planetary gear 4 has a connected to the first shaft 2 via an example dry first clutch 5 sun gear 6, first planetary gears 7 and second planetary gears 8, which are rotatably mounted on a planet carrier 9, and a first ring gear 10 and a second ring gear 11. Sun gear 6, planet carrier 9 and the two ring gears 10, 11 are rotatably mounted about a central axis 12.

The first ring gear 10 in this case has a smaller inner diameter di, as the second ring gear 11, whose diameter is designated d ₂ . The first planetary gears 7, 8 are in meshing engagement with the sun gear 6 and with the inner first ring gear 10, respectively. The second planetary gears 7, 8 in turn are in meshing engagement with the first planet gears 7 and the outer second ring gear 11, respectively.

The first ring gear 10 can be held by a brake 13. Via a second clutch 14, a rotational connection of the second ring gear 11 with the planet carrier 9 can be produced. The planetary gear 4 is thus blocked. The brake 13 and the second clutch 14 are preferably made wet. In place of the brake 13 may also be provided an overrunning clutch.

The second ring gear 11 can further be driven by an electric machine 15. In the example, for the rotor 16 of the electric machine 15 is fixedly connected to the second ring gear 11 or carried out integrally therewith. The planet carrier 9 is fixedly connected to the hollow shaft 17 which surrounds the first shaft 2 designed as a torsion shaft and which is drive-connected via a downstream intermediate transmission stage 18 and a final gear stage 19 or a transfer case with drive wheels.

With the drive train 1, the operating modes described below can be realized. In the Figs. 2 to FIG. 9, the torque fluxes are each indicated by arrows M _IC , M _EM , wherein the torque flux of the internal combustion engine is denoted by M _{IC and} the torque flux of the electric machine is designated by M _E M.

In the first gear, the torque M _{IC can be brought} from the internal combustion engine via the first shaft 2 to the closed first clutch 5 and passed through the sun gear 6 in the planet carrier 9. The smaller first ring gear 10 is held by the brake 13 and the first planetary gears 7 move the planet carrier 9, whereby the torque M _{IC is passed} through the downstream intermediate gear 18 and optionally a differential gear having gearbox final stage 19 in the drive wheels of the vehicle not shown , Via the second ring gear 11, the torque M _E M of the electric machine 15 can be introduced into the planet carrier 9. The wet second clutch 14 is open (see Fig. 2).

In the second gear, the torque M _{IC can be brought} from the internal combustion engine via the first shaft 2 to the closed first clutch 5 and passed through the sun gear 6 in the planet carrier 9. The brake 13 is open. The small first ring gear 10 is thus no longer held by the open brake 13 and the planet gears 7, 8 move the second ring gear 11. By the closed second clutch 14, a direct rotational connection between the planet carrier 9 and the second ring gear 11 is made, whereby the torque M _IC via the planet carrier 9, the downstream intermediate transmission stage 18 and the transmission gearbox having a differential gear 19 is guided in the non-illustrated drive wheels of the vehicle. Via the second ring gear 11, the torque M _E M of the electric machine 15 can be introduced into the planet carrier 9. The wet second clutch 14 is closed and the brake 13 is opened (FIG. 3). The transmitted torque is lower in second gear than in first gear.

In each gear additional torque M _EM can be introduced by the electric machine 15 to the drive or torque M _{EM are passed} to the electric machine 15 for braking or power generation. In this case, the second ring gear 11 is additionally driven by the electric machine 15 (Fig. 2, 3) or delayed by these (Fig. 6, 7) by the electric machine 15 is operated as a generator.

After opening the first clutch 5, purely electric drive via the electric machine 15 (Fig. 4, 5) is possible.

In the case of the purely electric drive in 1st gear passes torque M _E M of the electric machine 15 via the second ring gear 11 in the planet carrier 9. The wet second clutch 14 is open and the brake 13 is closed. Via the intermediate gear stage 18, the torque M _E M is conducted into the gearbox final stage 19 (FIG. 4).

In the case of the purely electric drive in 2nd gear, torque M _E M of the electric machine 15 passes through the second ring gear 11 into the planet carrier 9. The wet second clutch 14 is closed and the brake 13 is opened. Via the intermediate stage 18, the torque M _{EM is conducted} into the gearbox final stage 19 (FIG. 5).

A division of the torque M _{EM of} the internal combustion engine between the vehicle drive and the drive of the generator-operated electric machine 15 for charging a battery not shown in the 1st gear, by the torque M _EM of the internal combustion engine via the first shaft 2 to the closed clutch. 5 is brought and is passed over the sun gear 6 in the planet carrier 9. The smaller first ring gear 10 is held by the brake 13, the first planetary gear 7 thus moves the planet carrier 9. On the gear intermediate 18 passes on the one hand a portion of the torque M _EM in the Getriebefinalstufe 19 with the differential gear in the drive wheels of the vehicle and on the other hand the other Part via the second ring gear 11 in the electric machine 15, which now acts as a generator. The wet second clutch 14 is open (FIG. 6).

In second gear, the torque split between vehicle drive and charging the battery is carried out by the torque M _{EM of} the engine is brought via the first shaft 2 to the closed clutch 5 and is passed through the sun gear 6 in the planet carrier 9. The smaller first ring gear 10 is no longer held by the brake 13 and the planetary gears 7 and 8 move the second ring gear 11. This is connected by the closed wet second clutch 14 to the planet carrier 9. About the intermediate gear 18 passes a portion of the torque in the Getriebefinalstufe 19 with the differential in the drive wheels of the vehicle and the other part via the second ring gear 11 in the electric machine 15, which now acts as a generator. The wet second clutch 14 is closed and the brake 13 is opened (FIG. 7).

When charging the battery through the vehicle, the path of torque reverses. In the first gear, the torque passes from the drive wheels via the Getriebefinalstufe 19 in the intermediate gear 8 and from there into the planet carrier 9. About the second ring gear 11, the electric machine 15 is driven and now acts as a generator. The wet second clutch 14 is open and the brake 13 is closed (FIG. 8)

When charging the battery by the vehicle in second gear, the torque from the drive wheels via the Getriebefinalstufe 19 enters the intermediate gear 18 and from there into the planet carrier 9. About the second ring gear 11, the electric machine 15 is driven and now acts as a generator. The wet second clutch 14 is closed and the brake 13 is opened (FIG. 9).

The shift elements 13 (brake), 14 (second clutch), and 5 (clutch) are operated in the electric driving EM and IC driving modes VKM in the first embodiment as follows, with "X" for activated and "0" for deactivated:

10 shows schematically a drive train 1 for a hybrid vehicle in a second embodiment variant with a driven by an internal combustion engine ICE first shaft 2 and a driven second shaft 3, wherein between the first and second shaft 2, 3, a planetary gear 4 is arranged. The planetary gear 4 has a connected to the first shaft 2 via an example dry first clutch 5 sun gear 6, first planetary gears 7 and second planetary gears 8, which are rotatably mounted on a planet carrier 9, and a first ring gear 10 and a second ring gear 11. special NEN 6, planet carrier 9 and the two ring gears 10, 11 are rotatably mounted about a central axis 12.

The first ring gear 10, as in the first embodiment has a smaller inner diameter di, as the second ring gear 11, whose diameter is designated d ₂ . The first planetary gears 7, 8 are in meshing engagement with the sun gear 6 and with the inner first ring gear 10, respectively. The second planetary gears 7, 8 in turn are in meshing engagement with the first planet gears 7 and the outer second ring gear 11, respectively.

The first ring gear 10 can also be held here via a brake 13. Via a second clutch 14, a rotational connection of the second ring gear 11 with the planet carrier 9 can be produced. The planetary gear 4 is thus blocked. The brake 13 and the second clutch 14 are preferably made wet. In place of the brake 13 may also be provided an overrunning clutch.

The second ring gear 11 may further via an electrical machine 15 being trie ^¬ ben. In the example, for the rotor 16 of the electric machine 15 is fixedly connected to the second ring gear 11 or carried out integrally therewith.

The planet carrier 9 is fixedly connected to the formed as a torsion shaft first shaft 2 surrounding hollow shaft 17, which is drive connected via a downstream intermediate transmission stage 18 and a Getriebefinalstufe 19 or a Verteilerge ^¬ drive with drive wheels.

In contrast to the microcomputer shown in Fig. 1 to Fig. 9 Ausführungsbei ^¬ play between the coupling 5 and the sun gear 6 of the planetary gear 4 is a further gear stage 20 with a, for example, interlocking shift ^¬ clutch 21 with the two positions Sl and S2 are provided. This thus allows four gear ratios.

With the drive train 1 shown in FIG. 10, the operating modes described below can be realized. In FIGS. 11 to 16, the torque fluxes are each indicated by arrows M _IC , M _E M, wherein the torque flux of the internal combustion engine ICE is denoted by M _{IC and} the torque flux of the electric machine 15 is designated by M _E M.

FIGS. 11 and 12 show purely electric driving. The electromotive drive can be done in the four quadrants of the map of the electric machine 15, thus an electric driving forward, as well as backward, and a motor and generator operation in both directions, possible. In purely electrical operation, either the clutch 21 is in a ner neutral position, or the clutch 5 is opened. As in the first embodiment, of course, a combined operation with the internal combustion engine ICE to support this or power generation possible, the clutch 5 is closed and the clutch 21 occupies one of the two positions Sl or S2.

Electric driving (EMI:

By closing the brake 13, the first gear for the electric driving EM is switched. A ratio i> 1 is generated according to the kinematic conditions in the planetary gear 4. The brake 13 supports the planetary carrier 9 against the housing G (FIG. 11).

By closing the clutch 14, the second gear for the electric driving EM is switched. There is no additional translation in the planetary gear 4 - the planetary gear rotates as a block with a translation i = l (Fig. 12).

Combustion engine driving (VKM):

By closing the brake 13 and actuating the positive clutch 21 (synchronization) to the position S2 or S1, the first gear (FIG. 13) and second gear (FIG. 14) of the combustion engine driving VKM are engaged. The brake 13 supports the planet carrier 9 against the housing G.

By closing the second clutch 14 and operating the positive clutch 21 (synchronization) in the position S2 and Sl, the third gear (FIG. 15) and fourth gear (FIG. 16) of the combustion engine driving VKM is engaged. The second clutch 14 blocks the planetary gear 4.

The clutch 5 is closed in each gear at the VKM. During the switching operation, however, the clutch 5 must be opened.

The switching elements brake 13, second clutch 14, clutch 5 and clutch 21 (positions Sl and S2) are operated in the modes of electric driving EM and combustion engine driving VKM in the second embodiment as follows, with "X" for activated and "0" for disabled stands: Operating mode gear shift elements

13 14 5 Sl S2 l.gang X 0 0 - -

Electric driving EM

 2nd gear 0 X 0 - -

Combustion engine speed X 0 X 0 X Toric driving VKM

 2nd gear X 0 X X 0

3rd gear 0 X X 0 X

4th gear 0 X X X 0

The present drive concept represents a combination of power-split and parallel system. Due to the fact that the drive takes place on the one hand via a ring gear 11, on the other hand via the sun gear 6, a parallel drive mode can be realized with both drive machines. The internal combustion engine ICE can act on the sun gear 6, the electric machine 15 on a ring gear 11. Conversely, it is also possible to let the internal combustion engine ICE act on a ring gear and the electric machine 15 on a sun gear 6.

Claims

PATENT APPLICATIONS A planetary gear (4) having a sun gear (6) rotatably mounted about a central axis (12) and having at least one first planet gear (7) in mesh with the sun gear (6) arranged coaxially with the sun gear (6) first ring gear (10) is in meshing engagement with at least one second planet gear (8) which meshes with a second ring gear (11) coaxial with the sun gear (6), said first and second planet gears (6, 7) being rotatable on a about the central axis (12) rotatably mounted common planet carrier (9) are arranged, wherein the first planetary gear (7) with the second planet gear (8) meshing, characterized in that the planetary gear (4) via a preferably wet running second clutch (14) is lockable. 2. Planetary gear (4) according to claim 1, characterized in that the second ring gear (11) has a larger inner diameter (d ₂ ) than the first ring gear (10). 3. planetary gear (4) according to claim 1 or 2, characterized in that the axis of rotation (8 ') of the second planetary gear (8) further from the central axis (12) is spaced as the axis of rotation (7') of the first planetary gear (7 ), wherein preferably the axis of rotation (8 ') of the second planetary gear (8) between the axis of rotation (7') of the first planetary gear (7) and the second ring gear (11) is arranged. 4. Planetary gear (4) according to any one of claims 1 to 3, characterized in that the sun gear (6) with a on or abtreibenden first shaft (2) and the planet carrier (9) with a ab- or driving second shaft (3 ) is connectable. 5. powertrain (1) for a vehicle, comprising a planetary gear (4) according to claim 1, characterized in that at least one ring gear rotatably mounted about a central axis (12), preferably the second ring gear (11) an electric machine (15) is drivingly connected, wherein preferably this ring gear (11) with the rotor (16) of the electric machine (15) fixedly connected or integral with the rotor (16) of the electric machine (15) is formed. 6. Drive train (1) according to claim 5, characterized in that at least one rotatable about the central axis (12) mounted ring gear, Preferably, the first ring gear (10) is connected to a preferably wet-running brake (13) or an overrunning clutch. 7. powertrain (1) according to claim 5 or 6, characterized in that the sun gear (6) via a preferably dry-running first clutch (5) with a connected to an internal combustion engine first shaft (1) is drive-connected. 8. Drive train (1) according to one of claims 5 to 7, characterized in that the planet carrier (9) via a preferably wet-running second clutch (14) with the second ring gear (11) is rotatably connected. 9. Drive train (1) according to one of claims 5 to 8, characterized in that the planet carrier (9), preferably via a transmission intermediate stage (18), is drivingly connected to a driven-off second shaft (3). 10. Drive train (1) according to one of claims 1 to 9, characterized in that an additional gearbox, preferably for two gear ratios, in the drive train (1) - preferably between the internal combustion engine (ICE) and the planetary gear (4) - is arranged. 2012 09 04 Fu / Ka