DE102016201223A1 - Planetary gear for a motor vehicle - Google Patents

Abstract

The invention relates to a planetary gear (9) for a motor vehicle, comprising at least one drive shaft (1), at least one output shaft (2) and at least one between the at least one drive shaft (1) and the at least one output shaft (2) arranged and driven with these The stepped planetary gear set (3) with a ring gear (4) meshes, wherein further the ring gear (4) via a switching element (6) stationary on the housing (5) of the planetary gear (9) can be fixed to a To realize torque transmission between the at least one drive shaft (1) and the at least one output shaft (2). Furthermore, the invention also relates to a drive device for a motor vehicle, comprising an electric machine (8) and the aforementioned planetary gear (9).

Description

The invention relates to a planetary gear for a motor vehicle. Furthermore, the invention also relates to a drive device for a motor vehicle, comprising an electric machine and the aforementioned planetary gear.

The DE 10 2012 021 291 A1 discloses a speed change gearshift apparatus for a motor vehicle, comprising at least one transmission input shaft drivingly connected to a power plant, at least one output shaft, a plurality of fixed gear gear sets and synchronous clutch engageable idler gears for forming forward gears. The loose gear can be coupled via a clutch with a housing-fixed locking element to form a parking brake.

The object of the present invention is to develop a planetary gear with a stepped planetary set to the effect that a freewheeling of the planetary gear via the stepped planetary gear set is realized by simple means.

The planetary gear according to the invention for a motor vehicle comprises at least one drive shaft, at least one output shaft and at least one arranged between the at least one drive shaft and the at least one output shaft and drivingly connected thereto stepped planetary set, wherein the stepped planetary gear meshes with a first and a second ring gear, wherein further Ring gear via a switching element is fixed to the housing of the planetary gear fixed in order to realize a torque transmission between the at least one drive shaft and the at least one output shaft.

In other words, the switching element between the ring gear and the housing is arranged and allows in an open switching position, a free rotation of the ring gear. In a closed switching position of the switching element, the ring gear is mechanically coupled to the housing and thus fixed stationary on the housing. A closed switching position of the switching element realizes a translation via the stepped planetary set. If the switching element has an open switching position, a freewheeling function is realized via the stepped planetary set. Consequently, no drive power is transmitted via the stepped planetary gear set to the output shaft.

Preferably, the switching element produces a positive or non-positive connection between the ring gear and the housing. For example, the switching element may be designed as a clutch, preferably a multi-disc clutch, in order to enable a harmonious transition when closing the shifting element. In particular, the switching element is mechanically, electrically, pneumatically or hydraulically switchable.

The invention includes the technical teaching that the at least one drive shaft is connected to a sun, wherein the sun meshes with the at least one step planetary gearset. Preferably, the at least one output shaft is connected to a web, wherein the at least one step planetary set is rotatably mounted on the web. Thus, the at least one step planetary set meshes radially between the ring gear and the sun.

In particular, the stepped planetary set has a first toothed area with a first diameter and a second toothed area with a second diameter. The two toothed areas are rotatably connected to each other. Preferably, the first diameter is smaller than the second diameter.

A drive device according to the invention for a motor vehicle comprises an electric machine and the aforementioned planetary gear. Thus, the use of the planetary gear in an at least partially electrically driven motor vehicle is proposed. Preferably, the electric machine is designed as a permanent magnet synchronous machine. Furthermore, it is conceivable that the electric machine is a separately excited synchronous machine or an asynchronous machine.

Further measures improving the invention will be described in more detail below together with the description of a preferred embodiment of the invention with reference to the two figures. Show it

1 a simplified schematic representation of a drive device according to the invention with a planetary gear according to the invention and a switching element according to a first switching position, and

2 a simplified schematic representation of the drive device according to the invention with the planetary gear according to the invention and the switching element according to a second switching position.

According to the 1 and 2 has a drive device for a - not shown here - motor vehicle, an electric machine 8th and a planetary gear 9 on. The electric machine 8th is preferably designed as a permanent magnet synchronous machine and provided to electrically drive the motor vehicle. Furthermore allows the electric machine 8th For example, during a braking process of the motor vehicle, a conversion of kinetic energy into electrical energy, which can be fed for example in an - not shown here - electric accumulator.

The planetary gear 9 includes a drive shaft 1 , an output shaft 2 and a stepped planetary set 3 , The step planetary set 3 is between the drive shaft 1 and the output shaft 2 arranged and driven with the drive shaft 1 and the output shaft 2 connected. This is the drive shaft 1 with a sun 10 connected, the sun being 10 with the stepped planetary set 3 combs. Furthermore, the output shaft 2 with a jetty 7 connected on which the stepped planetary set 3 is rotatably mounted. Furthermore, the stepped planetary set meshes 3 with a ring gear 4 that has a switching element 6 stationary on the housing 5 of the planetary gear 9 can be fixed to a torque transmission between the drive shaft 1 and the output shaft 2 to realize. The step planetary set 3 has a first gearing area 11a with a first diameter and a second toothing area 11b with a second diameter. The two toothed areas 11a . 11b are rotatably connected. The first gearing area 11a is in meshing engagement with the ring gear 4 , wherein the second toothed area 11b in mesh with the sun 10 stands. Furthermore, the first toothing region 11a a small diameter than the second gear portion 11b on.

According to 1 is the switching element 6 closed, so that a mechanical connection between the ring gear 4 and the housing 5 consists. The drive power from the electric machine 8th is via the drive shaft 1 and the step planetary set 3 with a translation to the output shaft 2 transfer.

To 2 is the switching element 6 opened, so no mechanical connection between the ring gear 4 and the housing 5 consists. The second ring gear 4b can rotate freely. Likewise, the step planetary set can also 3 rotate freely, so no drive power from the drive shaft 1 over the step planetary set 3 on the output shaft 2 is transmitted. Thus, a freewheeling function via the step planetary set 3 realized.

LIST OF REFERENCE NUMBERS

1

 drive shaft

2

 output shaft

3

 Stepped planet set

4

 ring gear

5

 casing

6

 switching element

7

 web

8th

 electric machine

9

 planetary gear

10

 Sun

11a, 11b

 toothed area

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been 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.

Cited patent literature

• DE 102012021291 A1 [0002]

Claims (8)

Planetary gear ( 9 ) for a motor vehicle, comprising at least one drive shaft ( 1 ), at least one output shaft ( 2 ) and at least one between the at least one drive shaft ( 1 ) and the at least one output shaft ( 2 ) arranged and with these drivingly connected step planetary set ( 3 ), whereby the stepped planetary set ( 3 ) with a ring gear ( 4 ), wherein furthermore the ring gear ( 4 ) via a switching element ( 6 ) stationary on the housing ( 5 ) of the planetary gear ( 9 ) is determinable to a torque transmission between the at least one drive shaft ( 1 ) and the at least one output shaft ( 2 ) to realize. Planetary gear ( 9 ) according to claim 1, characterized in that the switching element ( 6 ) a positive or non-positive connection between the ring gear ( 4 ) and the housing ( 5 ). Planetary gear ( 9 ) according to claim 1, characterized in that the at least one drive shaft ( 1 ) with a sun ( 10 ), the sun ( 10 ) with the at least one step planetary set ( 3 ) combs. Planetary gear ( 9 ) according to claim 1, characterized in that the at least one output shaft ( 2 ) with a bridge ( 7 ), wherein the at least one step planetary set ( 3 ) rotatable on the web ( 7 ) is stored. Planetary gear ( 9 ) according to claim 1, characterized in that the stepped planetary set ( 3 ) a first gearing area ( 11a ) with a first diameter and a second toothed area ( 11b ) having a second diameter, wherein the two toothed areas ( 11a . 11b ) are rotatably connected to each other. Use of a planetary gear ( 9 ) according to one of claims 1 to 5 in an at least partially electrically driven motor vehicle. Drive device for a motor vehicle, comprising an electric machine ( 8th ) and a planetary gear ( 9 ) according to one of claims 1 to 5. Drive device according to claim 7, characterized in that the electric machine ( 8th ) is designed as a permanent magnet synchronous machine.

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