DE102015207504A1 - Power-shiftable multi-speed transmission in planetary construction, in particular automatic transmission for a motor vehicle - Google Patents

Abstract

The transmission comprises three planetary gear sets (RS1, RS2, RS3), each having a first element, a second element and a third element, wherein the first element of a first planetary gear set (RS1) with the drive shaft (1) is rotatably connected via the a first clutch (16) having a sixth shaft (6) rotatably connected to the third element of a second planetary gear set (RS2) is detachably connectable via a second clutch (26) with the second element of the first planetary gear set (RS1) a third shaft (3) connected to the third element of the first planetary gear set (RS1) via a third clutch (34) with one with the first element of the second planetary gear set (RS2) and the first Element of a third planetary gear set (RS3) rotatably connected fourth shaft (4) and via a fourth clutch (35) with one with the third element of the third planetary gear set (R S3) and the second element of the second planetary gear set (RS2) rotatably connected fifth shaft (5) is detachably connectable, wherein the second element of the third planetary gear set (RS3) is coupled to the housing (G).

Description

The present invention relates to a powershiftable multi-speed transmission in planetary construction, in particular an automatic transmission for a motor vehicle, according to the preamble of patent claim 1.

Automatic transmissions, particularly for motor vehicles, include, in the prior art, planetary gear sets that are switched by means of friction elements, such as clutches and brakes, and usually with a slip element and optionally a lockup clutch, such as a hydrodynamic torque converter or a fluid coupling connected.

Automatically switchable vehicle transmissions in planetary construction in general are already widely described in the prior art and are subject to permanent development and improvement. Thus, these transmissions require a low construction cost, in particular a small number of switching elements, and in the case of sequential switching, double circuits, i. avoid switching on or off of two switching elements, so that in circuits in defined gear groups only one switching element is changed. Furthermore, to be reduced by means of such transmission of fuel consumption, which can be done on the one hand by reducing the internal transmission losses and on the other hand by operating the engine at the ideal operating point.

From the US 6,716,133 B2 is a power shift planetary multi-stage transmission forth, comprising three planetary gear sets and four switching elements, wherein an element of one of the planetary gear sets is coupled to the housing of the transmission.

The present invention has for its object a power-shiftable multi-speed transmission planetary design, in particular to specify an automatic transmission for a motor vehicle.

This object is achieved by the features of claim 1. Further advantages and advantageous embodiments will become apparent from the dependent claims.

Accordingly, an inventive power shift multi-speed transmission is proposed in planetary design, which has a drive and an output, which are arranged in a housing. Further, three planetary gear sets, hereinafter referred to as first, second and third planetary gear set, each having a first element, a second element and a third element, six rotatable shafts - hereinafter as drive shaft, output shaft, third, fourth, fifth and sixth Shaft designated - and four clutches provided whose selective intervention causes different ratios between the drive and the output.

According to the invention, the first element of the first planetary gear set is rotatably connected to the drive shaft of the transmission, which is detachably connectable via a first clutch to the third shaft of the second planetary gear rotatably connected sixth shaft, which via a second clutch with the second Element of the first planetary gear rotatably connected output shaft of the transmission is detachably connectable.

Fermer is the third shaft connected to the third element of the first planetary gear set, via a third clutch with the first member of the second planetary gear set and the first element of the third planetary gear set rotatably connected fourth shaft and a fourth clutch with the third element of the third planetary gear set and the second element of the second planetary gear rotatably connected fifth shaft releasably connectable, wherein the second element of the third planetary gear set is coupled to the housing.

According to the invention, the first element is formed by a sun gear of the respective planetary gear set, wherein the second element is formed in the case of a minus planetary gear set by a web and in the case of a plus planetary gear set by a ring gear of the respective planetary gear set. Furthermore, in the case of a minus planetary gear set, the third element is formed by the ring gear and, in the case of a plus planetary gear set, by the web of the respective planetary gear set.

A simple minus planetary gear known to include a sun gear, a ring gear and a web on which planet gears are rotatably mounted, each meshing with the sun gear and ring gear. In this way, the ring gear at a fixed web on a sun gear opposite direction of rotation. In contrast, a simple plus planetary gear includes a sun gear, a ring gear and a web on which inner and outer planetary gears are rotatably mounted, wherein all inner planetary gears mesh with the sun gear and all outer planetary gears with the ring gear, each inner planetary gear each having an outer Planet wheel meshes. As a result, the ring gear has the same direction of rotation when the web is held on as the sun gear and there is a positive stationary gear ratio.

The planetary gear sets of the transmission are preferably designed as negative planetary gear sets. According to the invention, in the context of functionally identical variants, at least one of the planetary gear sets of the transmission designed as minus planetary gear sets can be designed as a plus planetary gear set, if the web and ring gear connection are exchanged at the same time and the amount of the stationary gear ratio compared to the embodiment as a minus planetary gear set by 1 is increased.

In the transmission according to the invention, the first, second and fourth clutch are designed as Reibschaltelemente or lamellar switching elements, wherein the third clutch may be designed as a lamellar switching element or as a form-locking switching element, for example as a claw or synchronization.

Furthermore, the transmission can be preceded by a so-called hybrid head, namely a torque superimposition module which has at least one first input and one second input for drive devices and at least one output. Here, e.g. an internal combustion engine may be coupled to the first input, wherein a rotor of an electric machine may be coupled to the second input, and wherein a transmission input shaft of the transmission may be coupled to the output. In the context of further embodiments, the transmission can be preceded by a torsional vibration decoupling unit, for example a dual mass flywheel.

In an advantageous manner, the transmission can be hybridized in a simple manner if an electric machine is arranged on one of the shafts of the transmission, but preferably on the drive shaft.

The planetary gear sets may be axially arranged on the drive side in the power flow direction in the traction mode of the internal combustion engine of a vehicle, which comprises the transmission according to the invention, in the order of the first planetary gear set, second planetary gear set, third planetary gear set, thereby enabling a front-transverse or rear-transverse arrangement , It is also possible to arrange the planetary gear sets in the order of the third planetary gear set, the second planetary gear set, the first planetary gear set in the order of power flow in the traction mode of the internal combustion engine, which comprises the transmission according to the invention, whereby a standard arrangement, i. a coaxial design of drive shaft and output shaft is made possible.

In the transmission according to the invention, five forward gears and one reverse gear can be realized.

The inventive design of the multi-speed transmission results in particular for passenger cars suitable translations and increased overall spread, causing an improvement in ride comfort and a significant consumption reduction can be effected.

In addition, the construction cost is significantly reduced with the multi-stage transmission according to the invention by a small number of switching elements and planetary gear sets. Furthermore, in the multistage transmission according to the invention, a good efficiency in the main drives with respect to the drag and gear losses.

In addition, the transmission according to the invention is designed such that an adaptability to different drive train configurations is made possible both in the power flow direction as well as in space.

For starting, the transmission can be preceded by an additional starting element, for example a torque converter or a dry or wet starting clutch, alternatively one or two internal shifting elements, in particular a switching element closed in the first forward gear and / or reverse gear, can serve as a starting element.

The invention will be explained in more detail below by way of example with reference to the attached figures. These are:

1 a schematic view of a first preferred embodiment of a multi-speed transmission according to the invention;

2 : an exemplary circuit diagram for a multi-step transmission according to 1 ; and

3 : A schematic view of a second preferred embodiment of a multi-speed transmission according to the invention.

In 1 is an inventive multi-stage transmission with a drive shaft 1 , an output shaft 2 and three planetary gear sets RS1, RS2 and RS3, each having a first element, a second element and a third element, which are arranged in a housing G. At the in 1 As shown, the planetary gear sets are designed as minus planetary gear sets, wherein the first element is formed by a sun gear of the respective planetary gear set, the second element by a web and the third element by a ring gear of the respective planetary gear set.

According to the invention, in the context of functionally equivalent variants, at least one of the according to 1 Planetary gear sets designed as negative planetary gear sets can be designed as a plus planetary gear set, if at the same time the web and ring gear connection are exchanged and the amount of the stationary gear ratio is increased by 1 compared to the design as minus planetary gear set.

In the embodiment shown, the planetary gear sets RS1, RS2, RS3 axially arranged on the drive side in the power flow direction in the train operation of the internal combustion engine in the order third planetary gear set RS3, second planetary gearset RS2, first planetary gearset RS1 arranged, whereby a standard arrangement is made possible. According to the invention, the axial order of the individual planetary gear sets and the arrangement of the switching elements are freely selectable, as long as it allows the binding of the elements.

How out 1 can be seen, four switching elements, namely four clutches 16 . 26 . 34 . 35 intended.

The spatial arrangement of the switching elements can be arbitrary and is limited only by the dimensions and the external shape.

With these switching elements a selective switching of five forward gears can be realized. The multi-speed transmission according to the invention has a total of six rotatable shafts, which are referred to below as the drive shaft, output shaft, third, fourth, fifth and sixth shaft, wherein the drive shaft, the first shaft 1 and the output shaft, the second shaft 2 of the transmission.

According to the invention in the multi-stage transmission according to 1 provided that the first element of the first planetary gear set RS1 with the drive shaft 1 is rotatably connected, which via a first clutch 16 with the sixth shaft rotatably connected to the third element of the second planetary gearset RS2 6 is detachably connectable, via a second clutch 26 with the output shaft rotatably connected to the second element of the first planetary gearset RS1 2 is detachably connectable.

Referring to 1 is the third wave 3 connected to the third element of the first planetary gear set RS1, via a third clutch 34 with the fourth shaft rotatably connected to the first element of the second planetary gearset RS2 and the first element of the third planetary gearset RS3 4 and a fourth clutch 35 with the fifth shaft rotatably connected to the third element of the third planetary gearset RS3 and the second element of the second planetary gearset RS2 5 detachably connectable, wherein the second element of the third planetary gear set RS3 is coupled to the housing G (shaft 0 ).

The clutches of the transmission are preferably designed as Reibschaltelemente or lamellae switching elements, wherein the third clutch may be designed as a form-locking switching element or as a friction switching element.

In 2 is an exemplary circuit diagram of a multi-speed transmission according to 1 shown. The multi-speed transmission has five forward gears. For each forward gear two switching elements are closed. Out 2 It can be seen that with sequential switching mode only one switching element is switched on and one switching element has to be switched off, since two adjacent gear stages share a switching element.

The first forward gear of the transmission is obtained by closing the second and third clutch 26 . 34 , the second forward speed by closing the third and fourth clutch 34 . 35 , the third forward speed by closing the second and fourth clutch 26 . 35 , the fourth forward gear by closing the first and fourth clutch 16 . 35 and the fifth forward speed is achieved by closing the first and second clutches 16 . 26 , wherein the reverse gear by closing the first and third clutch 16 . 34 results.

Because the third clutch 34 the transmission is closed in the first forward gear and in reverse, it can be used as friction switch element serve as a gear-internal starting element. Alternatively, the second clutch 26 as an internal gear starting element in the first forward gear and the first clutch 16 be used as internal gear starting element for reverse gear.

This in 3 Functionally identical example shown differs from the embodiment according to 1 otherwise unchanged structure in that the planetary gear sets of the transmission are axially arranged on the drive side in the direction of force flow in the train operation of the internal combustion engine, in the order of the first planetary gearset RS1, second planetary gearset RS2, third planetary gearset RS3, thereby forming a front-transverse or rear-transverse Arrangement is made possible. By changing the axial order of the planetary gear sets, the circuit diagram remains 2 unchanged.

As already stated, at least one of the planetary gear sets of the transmission embodied as minus planetary gear sets in the examples shown can be designed as a plus planetary gear set, if the web and ring gear connection are exchanged at the same time and the amount of the stationary gear ratio is minus in comparison to the embodiment. Planetary gear set is increased by 1. In the case of a plus planetary gear set, the first element is formed by a sun gear of the respective planetary gear set, wherein the second element is formed by a ring gear and the third element by the web of the respective planetary gear set.

For example, in the embodiment according to 1 the first planetary gear set RS1 be designed as a plus planetary gear set, if otherwise unchanged transmission structure, the third wave 3 with the bridge and the output shaft 2 are rotatably connected to the ring gear of the first planetary gearset RS1. To the same translations as in the execution according to 1 to achieve otherwise unchanged gear assembly, the amount of stationary gear ratio of the first planetary gearset RS1 is increased by 1 compared to the design as a minus planetary gear set.

According to the invention, it is also optionally possible to provide additional freewheels at any suitable location of the multi-speed transmission, for example between a shaft and the housing or, if necessary, to connect two shafts.

On the drive side or on the output side, an axle differential and / or a distributor differential can be arranged.

LIST OF REFERENCE NUMBERS

1

first shaft, drive shaft

2

second shaft, output shaft

3

third wave

4

fourth wave

5

fifth wave

6

sixth wave

16

first clutch

26

second clutch

34

third clutch

35

fourth clutch

G

casing

RS1

first planetary gear set

RS2

second planetary gear set

RS3

third planetary gear set

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

• US 6716133 B2 [0004]

Claims (6)

Power-shiftable multistage transmission in planetary design, in particular automatic transmission for a motor vehicle, comprising a drive shaft ( 1 ), an output shaft ( 2 ) and three planetary gear sets (RS1, RS2, RS3), each having a first element, a second element and a third element and are arranged in a housing (G), wherein the first element by a sun gear of the respective planetary gear set (RS1, RS2 , RS3) is formed, wherein the second element in the case of a negative planetary gear set is formed by a land and in the case of a plus planetary gear set by a ring gear of the respective planetary gear set (RS1, RS2, RS3), wherein the third element in the case of a minus Planetary gear set is formed by the ring gear and in the case of a plus planetary gear set through the web of the respective planetary gear set (RS1, RS2, RS3), six rotatable shafts ( 1 . 2 . 3 . 4 . 5 . 6 ) as well as four couplings ( 16 . 26 . 34 . 35 ), whose selective engagement different transmission ratios between the drive shaft ( 1 ) and the output shaft ( 2 ), wherein the first element of a first planetary gear set (RS1) with the drive shaft ( 1 ) is connected in a rotationally fixed manner, which via a first coupling ( 16 ) with a with the third element of a second planetary gear set (RS2) rotatably connected sixth shaft ( 6 ) is detachably connectable, which via a second coupling ( 26 ) with the second element of the first planetary gear set (RS1) rotatably connected output shaft ( 2 ) is releasably connectable, wherein a third wave ( 3 ) connected to the third element of the first planetary gear set (RS1), via a third clutch ( 34 ) with a fourth shaft rotatably connected to the first element of the second planetary gear set (RS2) and the first element of a third planetary gear set (RS3) (US Pat. 4 ) and via a fourth clutch ( 35 ) with a third shaft of the third planetary gear set (RS3) and the second element of the second planetary gear set (RS2) rotatably connected fifth wave ( 5 ) is detachably connectable, wherein the second element of the third planetary gear set (RS3) is coupled to the housing (G). Power-shiftable multi-speed transmission according to claim 1, characterized in that the planetary gear sets (RS1, RS2, RS3) are designed as negative planetary gear sets. Power-shiftable multi-speed transmission according to claim 2, characterized in that at least one planetary gear set (RS1, RS2, RS3) is designed as a positive planetary gear set, wherein the web and Hohlradanbindung of the planetary gear set designed as plus planetary changed in comparison to the execution as a minus planetary gear set and the amount of the stationary gear ratio is increased by 1. Power-shiftable multi-speed transmission according to claim 1, 2 or 3, characterized in that the planetary gear sets (RS1, RS2, RS3) viewed axially in the direction of power flow in the train operation of the internal combustion engine of a vehicle, which comprises the transmission, in the order first planetary gear set (RS1), second Planetary gear set (RS2), third planetary gear set (RS3) or in the order third planetary gear set (RS3), second planetary gear set (RS2), first planetary gear set (RS1) are arranged. Power-shiftable multi-speed transmission according to claim 1, characterized in that five forward gears are realizable, wherein the first forward gear by closing the second and third clutch ( 26 . 34 ), the second forward gear by closing the third and fourth clutch ( 34 . 35 ), the third forward gear by closing the second and fourth clutch ( 26 . 35 ), the fourth forward gear by closing the first and fourth clutch ( 16 . 35 ) and wherein the fifth forward gear by closing the first and second clutch ( 16 . 26 ), wherein the reverse gear by closing the first and third clutch ( 16 . 34 ). Power-shiftable multistage transmission according to claim 1, 2, 3, 4 or 5, characterized in that the first, second and fourth clutch ( 16 . 26 . 35 ) are designed as Reibschaltelemente or lamellar switching elements, wherein the third clutch ( 34 ) may be designed as a lamellar switching element or as a form-locking switching element.

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