DE102010050070A1 - Drive train for motor vehicle e.g. tractor, has clutch unit i.e. double clutch, comprising counter-pressure disk that is rotatably fixed by support bearing with bearing inner ring, where inner ring is mounted at input shaft by tapered ring - Google Patents

Abstract

The train has a clutch unit i.e. double clutch, comprising a counter-pressure disk (8) that is rotatably fixed by a support bearing (27) i.e. ball bearing, with a bearing inner ring (29). The inner ring is mounted at a transmission input shaft i.e. hollow shaft, by a tapered ring (32). The inner ring includes a conical expansion part (34) whose slope corresponds to a slope of a wedge surface of the tapered ring. The slope of the expansion part or the surface is formed in a self-locking manner. The tapered ring is mounted in a ring groove of the shaft and made of spring steel.

Description

The invention relates to a drive train of a motor vehicle with a clutch unit comprising a counter-pressure disk which is rotatably supported by means of a support bearing, which comprises a bearing inner ring and a bearing outer ring to a transmission input shaft.

Such a drive train is from the DE 10 2005 037 514 known. The bearing of the counter-pressure disk of the double clutch is mounted there by means of a locking ring on the transmission input shaft or axially supported.

In the known from the prior art determination of the camp when dismantling there is the risk of damage to the camp. The bearing has to transmit the drag torque a press fit on the transmission input shaft. When disassembling the bearing is removed by a tool is attached to the bearing outer ring, since the bearing inner ring itself is unreachable. Even slight tilting leads to an uneven loading of the rolling balls, so that individual balls or parts of the track can be overloaded and damaged. This can lead to impressions that greatly reduce the life of the bearing.

An object of the invention is therefore to simplify the disassembly of the support bearing, in particular to reduce the risk of damage.

This object is achieved by a drive train of a motor vehicle with a clutch unit comprising a counter-pressure plate, which is rotatably supported by a support bearing comprising a bearing inner ring to a transmission input shaft, wherein the bearing inner ring is fixed by means of a wedge ring on the transmission input shaft. The clutch unit is preferably a double clutch, in which the two clutch discs of the two friction clutches act on the common counter pressure plate.

The wedge ring preferably has a slot. The wedge ring can be bent up for assembly.

The bearing inner ring preferably comprises a conical expansion whose pitch corresponds to a slope of a wedge surface of the wedge ring. The bearing inner ring and the wedge ring form a kind of conical compression bandage. As a result, the surface of the widening lies flat against the surface of the wedge ring.

The slope of the widening or wedge surface is preferably self-locking. After assembly, the support bearing is frictionally fixed in the axial direction of the transmission input shaft. Due to the frictional connection in the axial direction, a frictional connection in the circumferential direction is simultaneously effected for transmitting the drag torque.

The wedge ring is preferably mounted in an annular groove of the transmission input shaft. As a result, the wedge ring itself is axially fixed to the transmission input shaft.

The bearing inner ring preferably has a clearance fit with the transmission input shaft. As a result, the bearing inner ring can be slid onto the transmission input shaft with minimal force and also removed after the wedge connection has been released. For mounting, the bearing is pushed onto the shaft so far that the groove for the wedge ring is exposed. Force application point for a tool is the bearing inner ring. Then the wedge ring is raised so that it comes to lie in the groove. The support bearing is now released, so that its frustoconical widening pushes onto the wedge ring. In the axial direction as a frictional and positive connection is made in the direction of the engine, in the opposite direction, ie a force on the bearing in the direction of the parallel shift, is due to the self-locking of the spline a frictional connection.

The transmission input shaft is preferably a hollow shaft of a dual-clutch transmission.

The wedge ring is preferably made of spring steel. As a result, it can be bent up like a circlip and pulled onto the shaft. The support bearing is preferably a ball bearing, which comprises a bearing inner ring and a bearing outer ring as well as between two arranged rolling balls.

An embodiment of the invention will be described with reference to 1 to 3 explained in more detail. Showing:

1 a half section through a coupling unit according to the prior art;

2 the attachment of a support bearing on a transmission input shaft according to the prior art;

3 An embodiment of an inventive attachment of the support bearing on the transmission input shaft.

This in 1 illustrated coupling unit 1 As known in the art includes two friction clutches 2 . 3 , which are shown in the disengaged, ie open state. The clutch unit 1 is part of a drive train of a motor vehicle, wherein motor vehicle and tractors, machinery, trucks and the like are understood. The drive train connects an internal combustion engine with driven wheels and comprises, in addition to the clutch unit, a parallel shift transmission and further transmission means such as shafts, differential gear and the like. The clutch unit thus forms a double clutch, the two clutch discs 4 . 5 includes, which are connectable to different transmission input shafts.

The clutch discs 4 . 5 Wear radially outside friction linings 6 . 7 , which are axially clamped between one of the two friction clutches 2 and 3 common back pressure plate 8th and one of the respective friction clutch 2 respectively 3 associated pressure plate 9 . 10 , The back pressure plate 8th forms part of a flywheel, which is connected to a drive motor. The back pressure plate 8th is about axially extending portions, which are not shown here, with a drive plate 11 or a drive basket connected. The drive plate 11 is designed as a driver ring. The axially extending areas that connect between the back pressure washer 8th and the drive plate 11 can either be on the back pressure plate 8th or on the drive plate 11 be formed or on both parts 8th . 11 be at least partially provided. The drive plate 11 can be screwed either in the manner of a torque converter with a provided for example on the crankshaft of the drive motor drive plate or be connectable to a motor side arranged drive element via an axial connector.

In 1 are further an external transmission input shaft 23 , which is a hollow shaft, and an axially arranged in this inner transmission input shaft 24 shown. The outer transmission input shaft 23 is with the clutch disc 4 rotatably, for example via a spline, connected, corresponding to the inner transmission input shaft 24 with the clutch disc 5 rotatably, also connected for example via a spline.

The back pressure plate 8th is about a storage 12 Supported on the transmission side and fixed at least in an axial direction in order to axially absorb the closing forces required for at least one of the friction clutches. How out 1 is recognizable, have the clutch discs 4 and 5 axially between their two annular friction linings 6 and 7 a so-called pad suspension, which is a progressive construction and removal of the friction clutches 2 . 3 ensure transmissible torque over at least a portion of the actuation path.

The pressure plate 9 is indirectly or directly preferably via leaf spring-like elements with the counter-pressure plate 8th rotatably connected, but limited axially displaceable connected. The pressure plate 10 the friction clutch 3 is similar to the back pressure washer 8th drivingly coupled. At the counter pressure disc 8th is a box-like component 12 attached, which is designed here as a sheet metal lid. Axial on both sides of this component 12 are provided in an annular arrangement lever elements 13 . 14 provided by means of which the respective associated friction clutch 2 . 3 is operable.

The lever elements 13 . 14 can each form a ring-like component having the plate spring-like properties, that is resiliently changeable in its conicity. In the following, the combined to a ring-like component lever elements 13 . 14 as a lever spring 15 respectively 16 designated. These lever springs 15 . 16 preferably each have a spring property, which ensures that they tend to set up in a frusto-conical position, which is an open state of the friction clutches 2 and 3 equivalent.

The pressure plate 10 carries traction means 17 which extend axially and at its the pressure plate 10 opposite end 18 a pivot bearing or rolling overlay 19 carry on which the lever spring 16 is supported tiltable or pivotable. In the illustrated embodiment, the Abwälzauflage 19 integral with the traction means 17 formed and formed by a radially inwardly directed annular area.

The traction means 17 may be formed by individual distributed over the circumference hook-like components. Advantageously, these traction means 17 However, also be combined into a preferably made of sheet metal component, which has a preferably closed annular region, from which a plurality of axial legs can go out, with the pressure plate 10 are firmly connected.

Radial inside the rolling pad 19 is the lever spring 16 on an annular support ring 20 supported. The annular support ring 20 is axially between the box-like component 12 and the lever spring 16 clamped and forms part of an adjustment 21 , by means of at least the friction linings 7 occurring wear at least partially automatically compensated. On the adjustment device is not important for understanding the invention, so this will not be described here. To close the friction clutch 3 become the radially inner peaks 22 the lever spring 16 acted upon in the left direction. For this purpose, a closing force is at least substantially in the friction clutch 3 introducing actuating element, such as an actuating bearing provided, which is not shown in detail. Such an actuator forms part of an actuating system, which may be formed as a pneumatic, hydraulic, electrical or mechanically actuated actuating system or has a combination of the aforementioned actuation options, that is, for example, designed as an electro-hydraulic actuation system.

The torque transmission and the axial displaceability of the pressure plate 10 ensuring spring means, in particular leaf springs, in a conventional manner, the components 8th and 10 connect together, preferably have a defined axial bias, which ensures that the pressure plate 10 in the opening direction of the friction clutch 3 is charged. This means that in the illustrated embodiment, the pressure plate 10 axially in the direction to the left of the counter-pressure plate 8th pushed away by the mentioned prestressed leaf springs. This will make the friction linings 7 Approved. The bias of the corresponding spring means, in particular leaf springs, should continue to ensure that the Abwälzauflage 19 always axially in the direction of the radially outer portions of the lever spring 16 is urged.

2 shows a view of the attachment of the counter-pressure plate 8th as known from the prior art on the outer transmission input shaft 23 , The counterpressure plate 8th includes an opening in its radially inner region 24 for receiving a bearing outer ring of a support bearing 27 , The support bearing 27 Here is a ball bearing, in which case any other suitable for the purpose of rolling bearing be provided no. The opening 25 includes a stop lug 28 that the bearing outer ring 26 of the support bearing 27 at least in one direction. A bearing inner ring 29 is on the outer transmission input shaft 23 stored. A circlip 30 in a groove 31 the wave 23 is arranged, puts the bearing inner ring 29 in one of the axial directions. Because the stop nose 28 and the circlip 30 on both sides of the support bearing 27 are arranged, the ball bearing is fixed in both axial directions.

3 shows an embodiment of an inventive attachment of the support bearing on the outer transmission input shaft. Instead of a retaining ring fixing in the axial direction is done here by a wedge ring 32 , The wedge ring 32 is in a groove 33 the outer transmission input shaft 23 arranged. The bearing inner ring 29 of the support bearing 27 has a conical or frusto-conical widening 34 on. The slope of the cone of the expansion 34 corresponds to the slope of the surface of the wedge ring 32 , The wedge ring 32 So lies with the bearing inner ring 29 facing surface at the widening 34 at. Opposite the axial direction, for example, by the axis of rotation of the transmission input shafts 23 . 24 is given, this is with the reference numeral 35 provided, is the bearing inner ring facing wedge surface of the wedge ring 33 and also the corresponding widening 34 inclined by an angle α. The angle α is such that the contact between the wedge ring 32 and the bearing inner ring 29 self-locking.

The wedge shape itself ensures the axial position of the support bearing to the shaft. By the clamping force also the drag torque is supported in the circumferential direction. There is always a preload on the bearing. Due to the circumferential contour of the wedge ring 32 becomes the support camp 27 on the transmission input shaft 23 centered. This will also avoid imbalance. The cone angle is self-locking, for example 5 °. In order to absorb the maximum drag torque occurring in practice of a maximum of 5 Nm, 500 to 1,000 N of preload force are sufficient. The wedge ring 32 is slotted. The material selected is spring steel. This allows the wedge ring 32 similar to a circlip are easily mounted on the shaft without being deformed.

For assembly, the coupling is pushed onto the gear shafts. In this case, there is a clearance between the bearing inner ring and the outer transmission input shaft. The clearance fits in the axial direction of the outer transmission input shaft 23 beyond the groove for the wedge ring 32 out. In installation position has the bearing inner ring 29 So with respect to the outer transmission input shaft 23 a clearance fit. Possible point of force application for an assembly tool is the bearing inner ring 29 , Then the wedge ring 32 in the groove 31 inserted. The release system of the clutch now pushes the clutch onto the wedge ring 32 , The bearing inner ring of the protective bearing and the shaft are passed through the wedge ring 32 braced. To release the connection is with a tool back to the bearing inner ring of the support bearing 27 pressed until the wedge ring 32 exposed. Then the wedge ring 32 out of the groove 31 be removed and the support bearing 27 from the outer transmission input shaft 23 subtracted from.

LIST OF REFERENCE NUMBERS

1

A clutch unit

2

friction clutch

3

friction clutch

4

clutch disc

5

clutch disc

6

friction lining

7

friction lining

8th

Reaction plate

9

pressure plate

10

pressure plate

11

drive plate

12

box-like component

13

lever member

14

lever member

15

lever spring

16

lever spring

17

traction means

18

The End

19

rolling support

20

support ring

21

readjustment

22

sharpen

23

outer transmission input shaft

24

inner transmission input shaft

25

opening

26

Bearing outer ring

27

support bearings

28

stop lug

29

Bearing inner ring

30

circlip

31

groove

32

wedge ring

33

groove

34

conical expansion

35

axis of rotation

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 102005037514 [0002]

Claims (9)

Drive train of a motor vehicle with a clutch unit ( 1 ) comprising a counter-pressure disk ( 8th ) rotatably by means of a support bearing ( 27 ), which has a bearing inner ring ( 29 ), at a transmission input shaft ( 23 ), characterized in that the bearing inner ring ( 29 ) by means of a wedge ring ( 32 ) on the transmission input shaft ( 23 ). Drive train according to claim 1, characterized in that the wedge ring ( 32 ) has a slot. Drive train according to claim 1 or 2, characterized in that the bearing inner ring ( 29 ) a conical expansion ( 34 ) whose slope leads to a slope of a wedge surface of the wedge ring ( 32 ) corresponds. Drive train according to one of claims 1 to 4, characterized in that the slope of the expansion ( 34 ) or wedge surface is self-locking. Drive train according to one of claims 1 to 4, characterized in that the wedge ring ( 32 ) in an annular groove ( 31 ) of the transmission input shaft ( 23 ) is stored. Drive train according to one of claims 1 to 5, characterized in that the bearing inner ring ( 29 ) with the transmission input shaft ( 23 ) has a clearance fit. Drive train according to one of claims 1 to 6, characterized in that the transmission input shaft ( 23 ) is a hollow shaft. Drive train according to one of claims 1 to 7, characterized in that the wedge ring ( 32 ) is made of spring steel. Drive train according to one of claims 1 to 8, characterized in that the support bearing ( 27 ) is a ball bearing having a bearing inner ring ( 29 ) and a bearing outer ring ( 26 ) and between both arranged rolling balls.

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