GB2384285A

GB2384285A - Torque transfer device

Info

Publication number: GB2384285A
Application number: GB0304551A
Authority: GB
Inventors: Johann Jackel; Phillipe Schwederle; Christophe Schwartz; Martin Schindler
Original assignee: LuK Lamellen und Kupplungsbau Beteiligungs KG; LuK Lamellen und Kupplungsbau GmbH
Current assignee: Schaeffler Buehl Verwaltungs GmbH; LuK Lamellen und Kupplungsbau GmbH
Priority date: 1998-12-28
Filing date: 1999-12-20
Publication date: 2003-07-23
Anticipated expiration: 2019-12-20
Also published as: GB2384285B; GB0304551D0

Abstract

An axially flexible flywheel for mounting between a clutch and an engine. The flywheel has an axially flexible first disc part 1102 connectable to a crankshaft of the engine. An annular component part 1104 which forms the connection to the clutch is connected on a radially outer region of the disc part 1102. The first disc part 1102 is braced against the annular component 1104 by means of a tongue or tongues 1103 pressed out from the first disc part.

Description

TORQUE TRANSFER DEVICE The invention relates to a torque transfer device for the axial elastic connection of a crankshaft of an internal combustion engine to an output part of a drive train, more particularly a friction clutch or a fluid clutch such as a Fottinger clutch or hydrodynamic converter, at least comprising a disc part connectable to the crankshaft and on which an annular component part which forms the connection to the output part is connected on a radially outer region.

Torque transfer devices of this kind are known per se and are termed flexible flywheels since the design of the first disc part is made axially flexible and thus axial and/or bending vibrations of the crankshaft can be filtered out at least in part.

In order to restrict the maximum deflection of the axially flexible disc part, an arrangement is proposed in DE OS 44 02 257 which provides an intermediate part axially between the flexible disc part and the contact pressure plate so that after exceeding an axial play the intermediate part forms a stop for the contact pressure plate and thus defines the axial path of the disc part. After the play has been used up an arrangement of this kind is wherefore likewise axially very stiff and, particularly in the higher speed ranges, transfers vibrations from the crankshaft to the clutch and further component parts of the motor vehicle with practically no reduction. The absence of an axial stop endangers the satisfactory

operation of the clutch through the axial elasticity influencing the release process. An axially stiffer design of the disc part reduces the axial damping.

The object of the invention is therefore to provide an arrangement of a torque transfer device which shows over the entire useful speed range of the vehicle an improvement in the axial vibrations entering from the crankshaft. Furthermore the object of the invention is to design a corresponding torque transfer device which is simple and easy to assemble and to use component parts which can be used throughout the service life of the vehicle without any noticeable wear.

According to the invention, there is provided a torque transfer device for connecting a crankshaft of an internal combustion engine to an output'part of a drive train, the device comprising an axially flexible disc part connectable with the crankshaft and an annular component part which forms the connection to the output part mounted on the disc part at a radially outer region, wherein at least one radially extending tongue is formed out from the disc part and is supported on the component part.

A spring function can thus be integrated into the first disc part by providing separations-preferably with a part in the circumferential direction-of the disc material in the first disc part in the region of the fastening means which can be in particular rivet connections, whereby the axial elasticity can be increased in this region. By way of example separations can be

formed radially inside and/or radially outside of the fastening means or tongues can be free cut and/or formed in the circumferential direction and/or radially outwards and/or inwards and in which the fastening means are housed for connecting the annular component. The circumferentially formed tongues can thereby be aligned in the drive and/or coast direction.

Arrangements of this kind can be advantageous not only for setting up the axial elasticity of the torque transfer device but in particular also serve for the thermal insulation of the annular component part from the first disc part. Particularly when using the torque transfer device in connection wi - : h a friction clutch where the annular component part can serve as a contact pressure or pressure plate, very hig 1 temperatures can exist at the annular component which can have a negative effect on the material properties, for example the elastic properties, of the first component part at least over the service life of the torque transfer device.

Furthermore the second disc part as the component part fixing the friction engagement and/or at the same time axially tensioning the first disc part and the annular component part can depending on whether fixed on the first disc part or on the annular component part be in friction engagement with the annular component part or with the first disc part.

It can be further advantageous if the second disc part has a lesser axial stiffness than the first disc part.

The second disc part can furthermore have radially outwardly aligned tongues which are spread out over the circumference and are axially tensioned with the annular component part wherein the plate spring tongues can likewise fix a friction engagement with the annular component part.

Furthermore it can be advantageous to provide a torque transfer device for connecting a crankshaft of an internal combustion engine to an output part of a drive train, at least consisting of an axially flexible first disc part connectable to the crankshaft and on which an annular component part which forms the connection to the output part is mounted at a radially outer region, and wherein the second disc part is housed rotationally secured on the crankshaft and is in friction engagement with the annular component part and the element forming the friction engagement is an annular component part which has elastic properties in the radial direction and is in friction engagement with the annular component part or with the second disc part at the circumference.

This element can be formed as an undulating ring which has radially outwardly directed undulations and serves as a friction disc between the second disc part and the annular component part wherein the peaks of the undulations on the outer circumference are in friction engagement with the inner circumference of the annular component pua-ana the outsides of the troughs on the inner circumference are in friction engagement with the outer circumference of the

second disc part. The undulating ring cross-section can thereby be rectangular, circular or the like.

In a further development a radially resilient disc part can be provided which is set on the crankshaft and is in direct friction engagement on its outer circumference with the inner circumference of the annular component part.

The torque transfer device can be provided for a friction clutch wherein the annular component part can form a contact pressure plate for the clutch, and a torque which can be coupled and uncoupled from the internal combustion engine is transferred to a gear input shaft through friction linings and a contact pressure plate.

Furthermore in other embodiments the annular component can be formed as a mass ring on which a hydrodynamic converter or a Fottinger clutch is mounted secured against rotation.

Advantageously a starting gear ring is mounted on the annular component part on the outer circumference, for example on at least three axially aligned cams spread over the circumference. These cams can be formed axially in the direction of the crankshaft or in the opposite direction wherein an alignment of the cams in the direction of the crankshaft can be particularly advantageous for reasons of space. In order to save axial structural space it can be further advantageous to provide the first disc part with window-shaped recesses corresponding to the cams so that the cams can engage through same and can be displaced in the axial direction to the combustion engine for the purpose of holding the

starting gear ring. Furthermore the first disc part can have on its outer circumference a circumferential shaped area in the axial direction which is preferably remote from the starting gear ring and on which ignition markings are formed. This produces a particularly space saving arrangement where the first disc part is mounted axially between the starting gear ring and a mass part of the ring shaped component part wherein from the mass part of the annular component part the cams are arranged axially in the direction of the crankshaft and the ignition markings are arranged round the outer circumference of the annular component part.

For further optimising the first disc part profiled areas can be provided in the circumferential direction or in the radial direction on same to have a positive effecc on the axial stiffness of the disc part. By way of example a circumferential swage can be provided radially between the annular component part and the crankshaft wherein the swage is advantageously indented axially in the direction of the annular component part.

For easier assembly the first disc part can be centred on the annular component by means of the shaped area for the ignition markings whereby the annular component can be fitted with corresponding radially aligned centring cams. The annular component part is then advantageously connected to the first disc part, preferably by rivets or press-fit. The rivets can thereby be provided circumferentially at the radial level in the region of the

contact bearing face for the friction linings of a friction clutch.

The arrangement of a torque transfer device can likewise be advantageous where a first axially flexible disc part is a constituent part of a divided flywheel having a primary flywheel mass and a secondary flywheel mass relatively rotatable opposite same against a circumferentially acting energy accumulator, wherein the axially flexible disc part can be axially tensioned by means of a second disc part of lesser axial stiffness.

It can thereby be advantageous to design the primary and/or secondary flywheel mass axially flexible wherein the correspondingly axially flexible component part can be formed as a one-piece disc part or of stiff and elastic component parts in a compound'construction so that the primary and/or secondary flywheel mass is at least partially insulated with regard to vibrations from the crankshaft, which is loaded with axial or bending vibrations, through at least one axially flexible component in the force flow between the crankshaft and clutch. Thus by way of example a vibration insulation of the flywheel disc part of the secondary side, by way of example the pressure plate of a friction clutch, can be reached by means of an axially flexible disc part which is mounted on the primary part relatively rotatable against the action of the damping device, for example in the form of circumferentially acting energy accumulators, whereby the axially flexible disc part can also consist of circumferentially distributed disc segments.

Each axially flexible component part or disc part is associated with a second disc part which can likewise be constructed of circumferentially spaced disc segments and has a lesser stiffness than the first axially elastic disc part. The second disc part is thereby axially tensioned directly or indirectly with the corresponding axially flexible disc part and can thereby form for example ringshaped contact bearing faces which in the event of axial relative movement of the two disc parts relative to each other build up a friction torque which compensates at least in part the bending or axial vibrations produced from the crankshaft. It is evident that insulating the vibrations for damping the axial or bending vibrations of the crankshaft can also be advantageous for the vibrations entering from the drive train.

Advantageous designs for tensioning the axially flexible disc part with the second less stiff disc part can propose that the disc part can be housed with the first disc part on the crankshaft and can form radially outwards an annular contact bearing surface or friction surface or in a further embodiment is fixedly connected in a radially outer area to the axially flexible disc part, for example by rivets, and can form on its radially inner area an annular contact bearing face or friction face for the axially flexible disc part.

Furthermore it can be advantageous in the case of a divided flywheel to tension the axially flexible disc part with a less stiff disc part, wherein the tensioning disc

part is tensioned axially between the secondary side and the primary side, which thus at the same time can represent a friction device for relative rotations in the circumferential direction and a friction device in the case of an axial relative movement of the primary and secondary side. The friction surface can hereby be provided on the axially flexible disc part or on the stiff part and the fixing of the second disc part can be provided on the non-friction component on the opposite side. It can also be advantageous to fix the ring rotationally secured on neither of the two contact bearing faces whereby a friction surface is formed on the secondary side and a friction surface is formed on the primary side.

The invention will now be explained in further detail with reference to Figures 1 to 20 in'which : Figure 1 is a sectional view through an embodiment of a torque transfer device; Figure 2 shows a diagram illustrating the axial amplitude of the first disc part in dependence on the speed of the internal combustion engine compared with the prior art; Figures 3 to 13a show further embodiments of torque transfer devices in partial sectional

view, where applicable with detailed explanations and Figures 14-20 show embodiments of a torque transfer device in sectional view as a divided flywheel.

Figure 1 shows an embodiment of a torque transfer device 1 with the first disc part 2, the second disc part 3 and the annular component part 4.

The torque transfer device 1 is connected to the crankshaft 8 with the axial interposition of a reinforcement ring 5 on the crankshaft side and to the second disc part 3 on the other side of the first disc part 2 by means of screws 9 which engage through the openings 6 provided in the parts 2, 3,5. For easier assembly the reinforcement ring 5, the first and the second disc parts 2, 3 are riveted together so that one integral component part is formed wherein the rivets 7 are formed from the reinforcement ring 5 by axially pressing alternately in the circumferential direction to the openings 6 and are riveted to the second disc part 2.

In the further radial path of the first disc part 2 to the outside in order to optimise the axial space required this disc part is sharply angled directly radially outside of the reinforcement ring 5 axially in the direction of the crankshaft 8 at least about the axial extension of the reinforcement ring 5 and after reaching the desired axial stagger is aligned again parallel to the screw plane of

the screws 9. In the region of the outer diameter the first disc part 2 has a circumferential shaped area 10 axially remote from the crankshaft 8 so that the first disc part 2 is roughly pot-shaped in which circumferential ignition markings are formed which are detected by a transmitter (not shown) and transferred to an evaluator unit.

The annular component part 4 is mounted radially inside the axial shaped area 10 and is centred on the first disc part 2 by means of circumferentially spaced out centring cams 12. The axial and rotationally secured connection with the first disc part 2 is produced by means of circumferentially spaced rivets 13. The annular component part 13 is in the illustrated embodiment formed as a clutch pressure plate with sockets 14 and threaded bores 15 for holding the remaining clutch constituent parts as well as the friction face 16 which is brought into friction engagement with the clutch disc and has in its radially outer region circumferentially spread out countersunk rivets 13 for fixing the annular component part 4 with the first disc part.

At least two, preferably four or six circumferentially spaced out cams 17 are shaped out on the annular component part 4 radially outside of the rivet circle 13 and extend axially in the direction of the crankshaft, with each cam having radially on the outside a contact bearing surface 18 onto which a starting gear ring 19 is drawn. The starting gear ring 19 can be fixed by welding, caulking and/or shrink-fitting. Window-shaped recesses 20

corresponding to the cross-sectional profile of the cams 17 are provided in the disc part 2 in the contact area between the cams 17 and first disc part 2 whereby the cams 17 are passed through same so that the starting gear ring 19 is mounted at approximately the same axial height as the collar 21 belonging to the crankshaft 8, or at least at the same axial height as the end of the crankshaft so that the axial space required by the torque transfer device 1 is reduced and/or an improved behaviour of the annular component part 4 acting as the flywheel mass is obtained.

The second disc part 2 is riveted to the first disc part 2 and to the reinforcement ring 5 to form one structural unit 1 which is mounted and screwed on the crankshaft 8.

Radially outwards the second disc part 3 substantially follows the first disc part 2 and is tensioned in the region of its outer circumference on the end side remote from the crankshaft with the end side of the annular component part 4 facing the first disc part, that is the second disc part is formed axially resilient, preferably with a lesser stiffness than the first disc part 2.

Radially outside the screws 9 or rivets 7 the second disc part 3 has tongues or spring tongues 22 radiating radially outwards and spread out over the circumference tensioned with the annular component part 4 wherein radially outwardly aligned swages 23 are formed on the annular component part 4 on the contact bearing faces corresponding to the number and shape of the tongues 22, so that these swages can also form an additional guide for

the tongues 22 in the circumferential direction and thus improve the friction engagement of the tongues 22 on the annular component part 4.

The function of the torque transfer device 1 is that bending vibrations of the crankshaft caused through the ignition processes of the individual cylinders of the internal combustion engine create an axial vibration of the first disc part 2 which compared with stiff flywheels absorbs these vibration ? in part and does not transfer them to the clutch or converter to the same extent as the stiff flywheels. Indeed a decreasing axial stiffness improves the transfer behaviour of these vibrations, but the release process of the clutch is affected where the cc-ordination is too soft In the illustrated embodiment of a torque transfer device 1 therefore the second disc part 3 as an axially less stiff component part is assigned parallel to the first disc part 2 wherein the second disc part 2 fixedly clamped only on one side-here on the first disc part 2-and axially tensioned on the other side produces friction engagement.

In the event of axial displacement of the first disc part 2 through a bending vibration of the crankshaft 8, for example with an amplitude up to two millimetres, preferably one millimetre, this is deflected in the radial area predetermined by the screws 9 as fixing point and the rivets 13 which counteract a torque arising through the stiffness of the clutch construction, so that the second

disc part 3 is tensioned with the annular component part 4 axially degressive against its stiffness, that is with a lesser contact bearing force as the axial deflection increases, and corresponding to the axial displacement of the first disc part 2 and thus of the annular component part 4, friction is produced between the second disc part 3 and the annular component part in the radial direction.

The effect of the damping device thus formed will be explained in further detail with reference to the diagram shown in Figure 2. Vibrations arise with the amplitude A in the drive train in dependence on the speed U of the internal combustion engine. The embodiment of a torque transfer device 1 is tuned to eliminate these vibrations and shows the behaviour 50 illustrated in Figure 2 compared to a behaviour 51 of a flexible flywheel or axially flexible flywheel according to the prior art without the second disc part 3.

At an engine speed range U between U1 2000jmin and Us 6000/min an excitation of the drive train only occurs compared with the prior art at higher speeds U, for example at about 4000 U/min. The amplitude of the excitation maximum is furthermore reduced with the design 1 by half compared to the prior art. The vibration behaviour has except for high-seldom used-speeds, in the overall speed band lower vibration amplitudes than a design fitted without the second disc part 3.

Figures 3 to 8 show further embodiments of torque transfer devices wherein only the upper half of the device turning

about its axis of rotation is shown in sectional view and which agree with the embodiment 1 of Figure 1 except for the differences described below regarding the corresponding figures so that the explanations made relating to Figure 1-where transferable-also apply to the embodiments described below.

Figure 3 shows an embodiment of a torque transfer device 101 wherein the first disc part 102 has a circumferential swage 123 for optimising the axial stiffness of the torque transfer device 101 wherein the swage 123 preferably has the indentation axially in the direction of the second disc part 103.

The second disc part 103 is set on the crankshaft 108 axially between the reinforcement ring 105 and the first disc part 102.

The annular component part 104 is provided as a clutch pressure plate for holding the clutch and has on the end side remote from the crankshaft 108 a shoulder 124 adjoined by the second disc part 103 with friction engagement under axial tension. The tensioning is thereby produced axially against the first disc part 102 with a progressive contact pressure force, that is the contact pressure force and the friction engagement resulting therefrom increases as the deflection of the first disc part 102 increases. To fix a defined friction surface which is not worked into the shoulder 124, the second disc part 103 is guided axially in an arc round the shoulder 124 and is formed on the outer circumference leading

axially away from the shoulder 124 so that the friction engagement is produced with the annular component part 104 through a circumferential contact bearing face 125.

Figure 4 shows a further possibility of providing a radially acting friction device in the torque transfer device 201. The second disc part 203 is axially tensioned axially between the annular component part 204 and the first disc part 202 without fixing the disc part 203 on the crankshaft. A shoulder 224 provided in the annular component part 204 and radially inwardly adjoining the part 203 serves to fix the second disc part 2 radially which can be formed as a diaphragm or plate spring with corresponding axial elasticity. The spring acts degressively with axial deflection of the first disc part and can produce a friction engagement on its outer and inner circumference wherein the second disc part 203 is deflected radially outwards through compression in the event of deflection of the first disc part 202 to thereby produce the friction engagement.

It is evident that the second disc part 202 can have on the outer and/or inner circumference circumferentially spaced out radially outwardly aligned tongues (not shown here) which engage in corresponding recesses or shaped areas of the disc part 202 and/or the annular component part 204 and thereby fix in the circumferential direction and/or in the radial direction at least on one of the parts 202,204 whereby other means, such as for example complementary profiles can also be used to fix the second

disc part 203 on the first disc part 202 and/or on the annular component part.

Figure 5 shows an example of a torque transfer device 301 wherein the second disc part 303 is hooked secured against loss with the annular component part 304 by means of axially aligned projections 325 provided on the outer circumference and corresponding circumferentially spaced indentations 324. The friction engagement in the radial direction can still be produced on the two parts 302,304.

Figure 6 shows an embodiment of a torque transfer device 401 wherein a disc part 403 which is radially elastic at least on the outer circumference is tensioned on the outer circumference with the inner circumference, which to this end has a corresponding contact bearing surface 423, of the annular component part 404. To optimise the friction surface the disc part is drawn radially inwards circumferentially on the outer circumference.

A damping action is produced by the first disc part 402 tilting on the screws 409 as turning point. The first disc part 402 is thereby supported radially on the second disc part 403 and causes an axial friction engagement between the annular component part 404 and the second disc part 403.

The torque transfer device 501 illustrated in Figure 7 follows the principle underlying the torque transfer device 401, with a modified structural solution. To this end the reinforcement ring 505 is designed as a second

disc part radially outwards and axially so that a circumferential gap is formed between it and the annular component part 504. An undulating ring 526 having a rectangular cross-section is inserted under radial tension in this gap and rubs with its outer undulations 526a on the inner circumference of the annular component part 504 and with its inner undulations 526b on the outer circumference of the reinforcement ring 505. Thus a damping device is formed which in the event of axial deflections of the first disc part 502 counteracts the deflection through the spring constant of the undulating ring 526 with a radial spring force over the annular component part and defines an axial friction engagement through the friction of the reinforcement ring 505 on the annular component part 504.

A shoulder 524 provided in the annular component part serves to prevent the undulating ring from escaping in the axial direction or the swage 523 of the first disc part serves in the other direction.

In Figure 8 the undulating ring 526 of Figure 7 having the rectangular cross-section is replaced by an undulating ring 626 having a circular cross-section. Axial fixing is by means of a circumferential groove 624 provided in the annular component part 604.

Figure 9 shows a longitudinal sectional view through an embodiment of a torque transfer device 701 which is identical with the torque transfer device 1 of Figure 1 except for the following differences.

The connection of the disc part 702 is in this embodiment not directly on the annular component part 704 which can be a pressure plate for a friction clutch, but is through a spring ring, or through circumferentially spaced out leaf springs on whose ore end the annular component part 702 is fixed and on whops} other end the annular component part 704 is fixedly attached, for example by rivets. The axial stiffness of the spring ring or of the leaf springs 750 can thereby be tune, d to the axial stiffness of the disc part 702 whereby an additional damping can be achieved of the axial nd/or bending vibrations of the crankshaft (not shown in this figure) in the direction of the drive train. In special applications the disc part 702 can be designed comparatively rigid, for example stiffer than for compensating axial vibrations relating to a resonance frequency in : he range from 200-250 Hz, that is stiffer than a range lependent on the clutch mass from 600 kg/mm to 2200 kg/mm, and the axial vibrations are to be dampened substantially by means of the axially elastic means 750 in the force flow between the disc part 702 and the annular component part 704.

Furthermore in order to form a damping system the second disc part 703 can be tensioned through friction engagement with the annular component part 704 by forming a friction device. An alternative or an additional friction device 751 can be provided between a component part of the disc part 702, such as for example the ignition marking ring 711, and a component part of the annular component 704, for example a shoulder 752 which is radially expanded on

its outer circumference and can consist of circumferentially spread out ring segments or a continuous nose which forms friction torque in the event of relative movement of the two component parts 702, 704.

In torque transfer devices, such as here the embodiment 701, an axial stop can be provided between the two parts 702, 704, which can be mounted in the region of the outer circumference and is here formed by the starting gear ring 719 and the ignition marking ring 711 which are axially spaced from each other by the distance x when in the state of equilibrium. The distance y can occupy a region of less than 1 mm, preferably a region of less than 0.3 mm.

The connecting means 750 through its low heat flow thermally insulates the disc part 702 adequately from the annular component part 704 which is subjected for example as a clutch pressure plate to great temperature fluctuations as a result of the friction engagement with the friction linings. Advantageously the connecting means is made from a material having a low heat conductivity, for example stainless steel. The combination of an axially flexible material with a material having poor heat conductivity is particularly advantageous.

Figure 9a shows a spring ring 750 forming the connection between the two parts 702,704 (Figure 9) and formed from several preferably four spring ring segments 750a. The spring ring segments are firmly connected, for example riveted or screwed, by means of openings 753, 754 over the

circumference alternately with the disc part 702 and the annular component part 704. As opposed to the use of leaf springs which are likewise advantageous the spring ring segments 750 are axially matched, whereby the axial stiffness can lie in a higher region. A further embodiment proposes overlapping the spring ring segments 750 and the disc part 702 or the annular component part 704 by means of fastening means engaging in the openings 753 of two spring ring segments, and the relevant other component part by means of the centre opening 754.

Figure 9b shows a closed spring ring 750b for the in particular axial flexible connection of the parts 702, 704 of Figure 9, wherein the openings 753a, 754a receive fastening means 713,713a alternating over the circumference of Figure 9 for fastening the disc part 702 to the annular component part 7-04.

In general the connecting part 750 of Figure 9 can have a single or multi stage spring rate-seen in the axial direction-, for which purpose the spring ring segments 750a and the spring ring 750b can have for example in the circumferential direction between the openings 753,754 or 753a, 754a an axial profiled section 755 or 755a which divides the spring area between two openings 753,754 or 753a, 754a into at least two different bending beams.

The torque transfer device 701 of Figure 9 can be built up with the elastic means 702,750 previously described, and the friction devices into a damping system for damping axial vibrations which can be specially adapted to any

type of internal combustion engine, drive train, drive and vehicle. To this end it is possible to combine together in particular the damping devices individually or jointly, single or multi stage, and several, for example two, friction devices producing different friction torques.

More particularly it can also be advantageous to combine together friction devices which supply axial and radial friction parts. It can also be advantageous to provide preferred damping devices for the bending vibrations and axial vibrations, wherein the bending vibrations can be damped by damping devices preferably mounted in the radially outer region. Thus it can be advantageous for example to dampen one type of vibration-bending vibration or axial vibration-preferably with the connecting means 750 of Figure 9 whilst the other type of vibration can be mainly damped by means of the elastic disc part 702 (Figure 9). The number of possible resonance maxima can be increased by introducing one or more damping elements (for example the spring ring 750) with different spring constants (where applicable in conjunction with at least one friction device, where greater friction work can be produced by using radially outer friction devices, as a result of the increased axial friction path-such friction devices being therefore especially advantageous). In this way a torque transfer device adapted to a drive train can dampen for example a typical resonance maximum for an axial vibration between 200 and 300 Hz and a resonance maximum for a bending vibration in the range from 600 to 800 Hz, and a better adaptation to the corresponding drive train can thus take place. It is thereby possible both to provide damping devices according

to the low pass filter principle known per se for axial and bending vibrations and also to dampen the individual resonance frequencies individually.

Figure 10 shows a partial sectional view of an embodiment of a torque transfer device 801 wherein the disc part 802 is connected directly to the annular component part 804 by means of the fastening means 813, such as rivets. In the

L-L immediate vicinity of the fastening means 813 the disc part is provided with a separation 856 which on the illustrated example is provided in a circular segment shape radially outside in connection with a further separation 856a radially inside the fastening means. The view A of Figure 10 shown in Figure lOA explains the cut of the separations 856,856a for a fastening means 813 which are distributed uniformly over the entire circumference.

Figures lOb-lOe show further advantageous design possibilities wherein in Figure lOb only a radially inner separation 856a is provided, in Figure 10c only a radially outer separation 856 and in Figures 10d and 10e separations 856b, 856c are provided each radially engaging round the fastening means 813, namely from radially outside 856c in Figure 10e and from radially inside 856b in Figure 10d.

The advantages of the torque transfer device 801 having the variable designs of separations 856,856, 856b, 856c lie in the thermal insulation of the two parts 802,804 from each other and in an axial flexibility wherein the

separations can advantageously be designed axially, for example by means of cold re-shaping technology. The torque transfer device 801 is to be manufactured costeffectively by sparing the connecting means such as 750 in Figure 9.

With a design of the torque transfer device 901-shown in Figure 11-similar to the torque transfer device 801, the separations 956 are guided through the formation of circumferentially cut tongues 986, which can be axially arranged and/or aligned in the drive and/or coast direction of the torque transfer devjce 901. The fastening means 913 are located in the tongues for connecting the disc part 902 with the annular component part.

A partial view B of Figure 11-is shown in Figure lla. Here tongues 986 are shown set up axially approximately parallel by means of two folded edges 987,987a and arranged alternately in the drive and coasting direction of the torque transfer device 901. It is evident that all the tongues 986 can be aligned in the drive or coasting direction. The advantages of the torque transfer device 901 correspond substantially to those of the torque transfer device 801.

A further advantageous development of a torque transfer device 1001 is shown in Figure 12 whose second disc part forming a friction engagement with the annular component part 1004 (cf. the disc part 3 of Figure 1) is connected integral with he connecting means 1050. To this end the

connecting means, in this case the spring ring 1050, has radially inwardly expanded projections 1003 which are adapted axially to the stagger relative to the annular component part 1004 and are tensioned axially with the annular component part 1004 to form friction engagement therewith.

Figure 12a shows a partial view of the spring ring 1050 with openings 1054 for receiving the fastening means 1013 for fixing the disc part 1002 and openings 1053 for receiving the fastening means for fixing the annular component part 1004. It is evident that the projections 1003 can also be arranged on the fastening means for fixing the annular component part.

The radially inwardly directed projections are expanded in the circumferential direction to increase for example the contact bearing face on the annular component part 1004.

Figure 12a shows a further design possibility of the projections 1003'on the spring ring 1050'. Here the circumferentially spread out projections 1003'are structurally separated from the spring ring 1050'and are fixed together with the fastening means for the disc part 1002 or the annular component part 1004 (Figure 12). This version is particularly advantageous when the material properties of the projections 1003 have to be different from those of the spring ring 1050', for example because the spring ring 1050'ought to have in addition thermally insulating properties.

Figures 13,13a show further advantageous variations of a torque transfer device 1101,1201, which are produced without a second disc part (cf. 3, Figure 1). The friction engagement with the annular component part 1104 is in this embodiment formed by circumferentially spread out tongues 1103 or 1203 formed out of the disc part 1102 or 1202. The tongues 1103 of the torque transfer device 1101 (Figure 13) are thereby aligned radially outwards and the tongues 1203 of the torque transfer device 1201 (Figure 13a) are aligned radially inwards. The tongues 1203,1103 can be axially set up so that they can adjoin the annular component part 1104 through axial tension which can be variable in size.

Figures 14 to 20 show advantageous embodiments of axially flexible disc parts in a divided flywheel wherein each axially flexible disc part is tensioned axially with a second disc part of lesser stiffness. Thus with axial relative movement of the parts relative to each other a friction contact is formed in the contact bearing area of the two disc parts which can lead to a damping of the axial vibrations. Equally a relative rotation of the two parts relative to each other can also be provided so that in addition a friction device is provided in the circumferential direction wherein here the axially flexible disc part is associated with the primary side or the secondary side and the second less stiff disc part is tensioned axially between component parts of the primary side on the one hand and of the secondary side on the other.

Figures 14 to 16 show embodiments which have an axially flexible disc part in the primary area and Figures 17 to 20 show axially flexible disc parts mounted on the secondary side.

Figure 14 shows a partial sectional view of a torque transfer device as a divided flywheel 1301. The axially flexible primary disc part 1302 is mounted and riveted on a hub 1302a wherein the hub is fixed for example by means of screws on the crankshaft (not shown). The primary disc part forms radially outside with a flange part 1302c a

chamber 1350b having inwardly extending biasing devices 1302 for the circumferentially acting energy accumulators 1350. Radially inside the energy accumulators 1350 a disc part 1302 is attached, for example as shown here by rivets, to the primary disc part 1302, and is axially tensioned on its inner circumference with the disc part 1302. In the event of relative movements of the two parts relative to each other a friction contact is hereby formed in the area 1303a between the disc part 1302 and the disc part 1303 with lesser stiffness so that in the event of axial vibrations of the disc part 1302 the latter can be damped.

The secondary disc part 1360 is mounted on the hub 1302a by means of a bearing 1361 and is relatively rotatable opposite the disc part 1302 relatively against the action of the energy accumulator 1350 or the energy accumulator 1350a belonging to a second damper stage. For biasing the energy accumulator 1350 or 1350a on the secondary side a flange part 1370 having corresponding recesses is

connected rotationally secured, for example by rivets, to the secondary disc part 1360. The secondary disc part 1360 houses a friction clutch (not shown).

Figure 15 shows a construction of a divided flywheel 1401 similar to Figure 14 having an axially flexible primary disc part 1402, a secondary disc part 1460 rotatable relatively opposite the disc part 1402 against the action of the energy accumulator 1450, as well as a disc part 1403 which has reduced stiffness compared to the stiffness of the disc part 1402 and which is mounted together with the primary disc part 1402 and a bearing dome 1460a for the secondary disc part 1460 on the crankshaft (not shown) and which is axially tensioned in the area 1403a with the disc part 1402 to produce a friction contact which in the event of axial vibrations of the primary side, more particularly of the disc part-1402, can have a damping action.

Figure 16 shows an embodiment of a divided flywheel 1501 which corresponds substantially to the embodiment 1401 of Figure 15 although there is the difference here that the second disc part 1503 is mounted with the primary disc part 1502 radially inside on the crankshaft (not shown) and is tensioned axially with the disc part 1502 radially level with the energy accumulator 1550, with the less stiff disc part 1503 being centred on the disc part 1502 by means of the centring nose 1503a. Furthermore the disc part 1503 has in the region of its outer circumference markings 1503b for the engine management system which are evaluated by a suitably arranged and designed sensor (not

shown in further detail). The disc part 1502 is axially reformed on its outer circumference and provided with an additional primary mass 1502a. The divided flywheels 1403 and 1303 of Figures 14 and 15 likewise have these primary masses in a more or less reduced circumference, with the flywheel mass being formed on the disc part 1302 of Figure 14 substantially by the shape of the disc part and of the additional disc part 1302c as well as by the starting gear ring.

In the embodiment of a divided flywheel 1601 shown in Figure 17 the secondary side is designed axially flexible and the secondary flywheel mass is tensioned against the secondary disc part axially by means of a less stiff disc part.

The construction of the divided flywheel 1601 is thereby divided into a primary d-suc part 1602 which is set on the crankshaft, a secondary disc part 1660 which is set rotatable on a bearing flange 1660a fitted on the primary side, and a secondary flywheel mass part 1661 fixedly connected, for example by rivets, to the secondary disc part 1660.

The secondary disc part 1660 and the primary disc part 1602 are mounted rotatable relatively against the action of the energy accumulators 1650 wherein these are biased on the primary side by pockets 1602a and on the secondary side by a radially aligned flange 1660b with corresponding recesses 1660c. Radially between the bearing, for example here a slide bearing 1660d, and the

circumferentially spaced rivets 1662 which connect together the flange 1660b, the flywheel disc 1661 and the secondary disc part 1660, the disc part 1660 is designed axially flexible so that axial vibrations or bending vibrations entering from the crankshaft through the disc part 1602 can be insulated in the secondary area and thus can be kept substantially away from the clutch, such as for example a friction clutch (not shown in further detail).

To this end, the disc part 1603 which has a reduced axial stiffness compared with the disc part 1660 is tensioned axially between the flywheel mass 1661 and the secondary disc part 1660, wherein in the illustrated embodiment the disc part 1603 is supported on a radially protruding stop shoulder 1661a on the inner circumference of the flywheel mass part 1661 against the secondary disc part 1660 and where applicable in the event of relative movement of the two parts 1661,1660 builds up a friction torque, preferably in the micro region. The disc part 1660 and/or the flywheel mass part 1661 can thereby serve as a friction partner.

Figure 18 shows a divided flywheel 1701 as described for the embodiment 1601 of Figure 17 except for the following differences which will be explained in further detail.

The design of the connection between the flange part 1760 and the flywheel mass part 1761 is different from the flywheel 1601 of Figure 1. Here these two parts 1760, 1761 are connected by means of an axially flexible disc

part 1765 which can also be formed from a number of circumferentially spread out disc segments, for example radially on the inside by means of circumferentially spread out rivets 1766 on the secondary disc part 1760 and radially on the outside by means of circumferentially spread out rivets 1767 with the flywheel mass part 1761.

The secondary disc part 1760 can thereby form the radial flange 1760b in one piece with the biasing devices 1760c and has increased stiffness relative to the axially more flexible disc part 1765 so that axial and/or bending vibrations entering from the crankshaft through the disc part 1702 are insulated substantially from the clutch on the disc part 1765.

Radially outside of the rivet circle 1767 the flywheel disc 1761 is tensioned axially with the flange 1760b, thus the secondary disc part 1760, whereby the means for axially tensioning is again a disc part 1703 which with regard to its stiffness is weaker than the disc part 1765. As shown, the disc part is placed against the flange 1760b and is supported radially inwards on the disc part 1765 or the associated rivets 1767. A friction torque can be built up both between the flange part 1760b and/or the disc part 1765 on one side and the disc part 1703 on the other. It is evident that the disc part 1765 can also be connected radially inside the fastening on the secondary disc part 1760 to the flywheel mass part 1761.

Figure 19 shows an embodiment of a divided flywheel 1801 wherein the disc part 1802 is formed axially flexible and is supported axially against the secondary side. To this

end the disc part 1803, for example a plate spring is tensioned axially between the secondary side and a flange part 1802 wherein the flange part 1802a is fixedly connected to the primary disc part 1802 for example by welding, and forms the chamber 1850a for holding the energy accumulators 1850. In the illustrated embodiment the disc part 1803 is fixed, for example by circumferentially spread out rivets 1862, axially between the flywheel mass part 1861 which is mounted rotatable relative to the disc part 1802 directly on the primary side on a bearing flang'1802b which in turn is connected to the crankshaft and t'primary disc part 1802, and the flange part 1861b which represents the biasing device of the secondary side for he energy accumulators 1850. A friction contact is theby produced in the region 1803a between the disc part 1 03 and the flange part 1802ahere on the outer circumference of the disc part 1803.

This friction contact produces a friction torque both in the case of an axial relative movement of the primary disc part 1802 through axial or bending vibrations and in the event of a relative : otation of the disc part 1802 relative to the flywhee mass part 1861, thus acts as a friction device for axiil or bending vibrations and for torsion vibrations, such as is known from friction devices

of divided flywheels. i̲ th an increase in the stiffness in the axial direction-t can be advantageous in order to reduce the basic friction during a relation rotation of the two component parts 1802, 1861 to mount the disc part 1801 rotatable relative to the secondary side, for example by means of a slide bearing. It can thereby also be advantageous to provide rotation with play so : hat from

the friction device originally formed as a basic friction it is possible to provide a friction device with torsional play.

Figure 20 shows in principle the construction of a divided flywheel 1901 similar to the embodiment 1801 in Figure 19 wherein the spring force of the disc part 1903 between the flange part 1902a and the flywheel disc 1961 is counteracted by a compensation spring 1903a which is axially supported on the disc part 1903 and on a shoulder 1961a of the flywheel mass part 1961. The spring constants of the two plate springs 1903,1903a are advantageously matched so that a small axial force acts on the contact bearing face 1902b and a large axial force acts on the contact bearing face 1903b of the two plate springs 1903,1903a. From this, for a relative movement between the primary side and secondary side, thus the disc part 1902 with the flange part 1902b on one side and the flywheel mass part 1961 with the flange part 1961b on the other side, against the action of the energy accumulator 1950 a small friction torque arises at the friction area 1902b and in the event of axial vibrations of the disc part 1902 with the flange part 1902a against the flywheel mass part 1961 a large friction torque arises at the contact bearing face 1903b.

The invention is also not restricted to the embodiments of the description. Numerous amendments and modifications are possible within the scope of the invention as defined by the claims, particularly those variations, elements and combinations and/or materials which are combinations or

modifications of individual features or elements or process steps contained in the drawings and described in connection with the general description and embodiments and claims.

Claims

CLAIMS 1. Torque transfer device for connecting a crankshaft of an internal combustion engine to an output part of a drive train, the device comprising an axially flexible disc part connectable with the crankshaft and an annular component part which forms the connection to the output part mounted on the disc part at a radially outer region, wherein at least one radially extending tongue is formed out from the disc part and is supported on the component part.
Torque transfer device as claimed in Claim 1. wherein the at least one tongue is axially supported.
3. Torque transfer device as claimed in Claim 1 or Claim 2, wherein the tongue forms friction engagement with the annular component part.
4. Torque transfer device as claimed in any preceding claim, wherein the connection of the disc part with the annular component is produced by circumferentially distributed fastening means in whose immediate vicinity there is at least one circumferentially aligned cut out area in the disc part.
5. Torque transfer device as claimed in Claim 4, wherein the separation is arranged radially inside and/or radially outside the fastening means.

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6. Torque transfer device as claimed in Claim 4 or Claim 5, wherein the separation is made in the form of a tongue and the fastening means is provided on the tongue.

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7. Torque transfer device as claimed in Claim 6, wherein the tongue is aligned radially or circumferentially.
8. Torque transfer device as claimed in Claim 6 or Claim 7, wherein the tongues are circumferentially spaced out either all in the coast direction, all in the drive direction or mixed up in the drive and coast direction.
9. Torque transfer de-ice as claimed in any preceding claim, wherein a second disc part is adapted to be rotationally secured on he crankshaft and is in friction engagement with the annular component part.
10. Torque transfer dev ce as claimed in Claim 9, wherein the friction engagement between the second disc part and the annular component art is produced by means of an undulating ring with ra ially outward aligned undulations wherein the undulations on the outer circumference are in friction engagement wit 1 the inner circumference of the annular component part and the undulations of the inner circumference are in f-iction engagement with the outer circumference of the second disc part.
11. Torque transfer device as claimed in Claim 10, wherein the undulating ring cross-section is rectangular or circular.

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12. Torque transfer device as claimed in any one of Claims 9 to 11, wherein the second disc part is radially resilient when mounted on the crankshaft and is in friction engagement directly by its outer circumference with the inner circumference of the annular component part.
13. Torque transfer device as claimed in any one of Claims 9 to 12, wherein the second disc part is adapted to be mounted axially on the crankshaft between the first disc part and a reinforcement ring.
14. Torque transfer device as claimed in any preceding claim, wherein the annular component part is a contact pressure plate for a clutch.
15. Torque transfer device as-claimed in any preceding claim, wherein a starting gear ring is housed on the outer circumference of the annular component part.
16. Torque transfer device as claimed in Claim 15, wherein the starting gear ring forms an axial stop for the first disc part.
17. Torque transfer device as claimed in Claim 15 or Claim 16, wherein the starting gear ring is housed on at least three axially aligned cams spread out round the circumference.

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18. Torque transfer device as claimed in Claim 17, wherein the cams are aligned axially in the direction of the crankshaft.
19. Torque transfer device as claimed in Claim 17 or Claim 18, wherein the cams engage through corresponding window-shaped recesses of the first disc part.
20. Torque transfer device as claimed in any preceding claim, wherein the first disc part has ignition markings formed on the outer circumference.
21. Torque transfer device as claimed in any one of Claims 15 to 20, wherein the first disc part extends radially outwards axially between the starting gear ring and a mass part of the annular component part.
22. Torque transfer device as claimed in any preceding claim, wherein the first disc part has a circumferential swage radially between the annular component part and a locator on the crankshaft.
23. Torque transfer device as claimed in Claim 22, wherein the swage is indented axially in the direction of the annular component part.
24. Torque transfer device as claimed in Claim 20, wherein the first disc part is centred on the annular component part by means of the shaped area.

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25. Torque transfer device as claimed in any preceding claim, wherein the annular component part is riveted to the first disc part.
26. Torque transfer device as claimed in Claim 25, wherein the riveting is produced circumferentially at the radial level in the region of the contact bearing surface for friction linings of a friction clutch.
27. Torque transfer device as claimed in any preceding claim, wherein the first disc part is part of a divided flywheel which has a primary flywheel mass and a secondary flywheel mass which is rotatable relative to the primary mass against a circumferentially acting energy accumulator, is axially flexible and is axially tensioned by means of a second disc part of lesser axial stiffness.
28. Torque transfer device as claimed in Claim 27, wherein the axially flexible disc part is associated with the primary or secondary flywheel mass.
29. Torque transfer device as claimed in Claim 27 or Claim 28, wherein the flexible first disc part is axially flexibly mounted on the crankshaft.
30. Torque transfer device as claimed in any preceding claim, wherein the first disc part is axially flexible and forms a secondary disc part for holding a friction clutch wherein a primary disc part, adapted to be mounted on the crankshaft, and the secondary disc part are mounted one on the other and are rotatable relative to each other in the

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circumferential direction against the action of at least one energy accumulator.
31. Torque transfer device as claimed in Claim 30, wherein the axially flexible disc part connects together a pressure plate of the friction clutch and the secondary disc part.
32. Torque transfer device as claimed in Claim 30 or Claim 3G, wherein the second disc part is mounted on the crankshaft and is tensioned radially outwards and axially against the primary disc part.
33. Torque transfer device as claimed in any one of Claims 30 to 32, wherein the second disc part is riveted round the circumference radially inwards or radially outwards with the primary disc part and is axially tensioned with the primary disc part radially in the opposite direction.
34. Torque transfer device as claimed in any one of Claims 30 to 33, wherein the second disc part is fixed on the secondary disc and is axially tensioned against the primary disc part or against the pressure plate.
35. Torque transfer device as claimed in any one of Claims 30 to 34, wherein the second disc part is fixed on the pressure plate or on the primary disc part and is tensioned axially against the secondary disc part or a component part connected thereto.

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36. Torque transfer device as claimed in Claim 35, wherein the component part connected to the secondary disc part is an axially acting energy accumulator.
37. Torque transfer device as claimed in any one of Claims 30 to 36, wherein the second disc part is rotatable relative to the axially flexible first disc part.
38. Torque transfer device as claimed in any one of Claims 30 to 37, wherein the axially flexible first disc part together with the second disc part form in their contact bearing area a friction device by means of relative rotation and/or an axial relative movement relative to each other.
39. Torque transfer device as claimed in Claim 38, wherein the friction device is liable to play.