GB2124334A - Torsional vibration damper, especially for motor vehicle drives provided with torque converters - Google Patents
Torsional vibration damper, especially for motor vehicle drives provided with torque converters Download PDFInfo
- Publication number
- GB2124334A GB2124334A GB08320027A GB8320027A GB2124334A GB 2124334 A GB2124334 A GB 2124334A GB 08320027 A GB08320027 A GB 08320027A GB 8320027 A GB8320027 A GB 8320027A GB 2124334 A GB2124334 A GB 2124334A
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- United Kingdom
- Prior art keywords
- disk
- disks
- vibration damper
- torsional vibration
- friction
- Prior art date
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F15/00—Suppression of vibrations in systems; Means or arrangements for avoiding or reducing out-of-balance forces, e.g. due to motion
- F16F15/10—Suppression of vibrations in rotating systems by making use of members moving with the system
- F16F15/12—Suppression of vibrations in rotating systems by making use of members moving with the system using elastic members or friction-damping members, e.g. between a rotating shaft and a gyratory mass mounted thereon
- F16F15/129—Suppression of vibrations in rotating systems by making use of members moving with the system using elastic members or friction-damping members, e.g. between a rotating shaft and a gyratory mass mounted thereon characterised by friction-damping means
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D3/00—Yielding couplings, i.e. with means permitting movement between the connected parts during the drive
- F16D3/02—Yielding couplings, i.e. with means permitting movement between the connected parts during the drive adapted to specific functions
- F16D3/14—Yielding couplings, i.e. with means permitting movement between the connected parts during the drive adapted to specific functions combined with a friction coupling for damping vibration or absorbing shock
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16H—GEARING
- F16H45/00—Combinations of fluid gearings for conveying rotary motion with couplings or clutches
- F16H45/02—Combinations of fluid gearings for conveying rotary motion with couplings or clutches with mechanical clutches for bridging a fluid gearing of the hydrokinetic type
- F16H2045/0221—Combinations of fluid gearings for conveying rotary motion with couplings or clutches with mechanical clutches for bridging a fluid gearing of the hydrokinetic type with damping means
- F16H2045/0226—Combinations of fluid gearings for conveying rotary motion with couplings or clutches with mechanical clutches for bridging a fluid gearing of the hydrokinetic type with damping means comprising two or more vibration dampers
- F16H2045/0231—Combinations of fluid gearings for conveying rotary motion with couplings or clutches with mechanical clutches for bridging a fluid gearing of the hydrokinetic type with damping means comprising two or more vibration dampers arranged in series
Abstract
A torsional vibration damper has a driving disk 12 and a driven disk 30 each accommodated between cover disks 13, 14 which are interconnected so as to be axially and rotationally fixed to each other. The driving and driven disks 12 and 30 are movable in the circumferential direction relatively to each other and with respect to the cover disks, 13, 14 and are supported circumferentially against the latter independently of each other via respective groups of damping springs 20, 40, 50 which are operative progressively in the circumferential direction and are accommodated in circumferentially extending openings distributed around the circumference and provided in the cover disks and in the driving and driven disks. In addition to the damping springs, friction stages (disks 22, 23; 42, 43; 48) are provided between the driving disk and the cover disks on the one hand and between the cover disks and the driven disk on the other hand, which become operative when relative movement occurs between these disks. <IMAGE>
Description
SPECIFICATION
Torsional vibration damper, especially for motor vehicle drives provided with torque converters
The invention relates to a torsional vibration damper according to the preamble of Patent
Claim 1, which has a driving disk and a driven disk each accommodated between cover disks which in turn are connected together so as to be axially and rotationally rigid with each other, which driving and driven disks are movable circumferentially relatively to each other and from time to time relatively to the cover disks, as well as being supported circumferentially against the latter independently of each other via respective groups of damping springs which act circumferentially from time to time and are accommodated in circumferentially distributed, circumferentially extending openings in the cover disks on the one hand and in the driving and driven disks on the other hand.
Torsional vibration dampers of this kind are, for example, necessary in motor vehicle drives with automatic gears in combination with torque converters or fluid couplings, in order to smooth out irregularities, shock loads and the like and in particular to check the instigation of torsional vibrations at the moment when it arises.
A two-stage torsional vibration damper of the kind referred to above for motor vehicle drives with torque converters is described in DE-OS 30 47 039, in which a driving disk driven by a torque converter and a driven disk fixed for rotation with a driven shaft are accommodated between cover disks and are supported with respect to the latter by damping springs which act in the circumferential direction, comparatively large relative movements being produced from time to time between the driving disk and the cover disks on the one hand and between the latter and the driven disk on the other hand due to the fact that in each stage there are several sets of springs which are arranged so that they are distributed around the circumference, each set of springs being composed of a plurality of damping springs connected in series with one another.
Moreover, radially disposed entrainment means are arranged between the damping springs of each set of springs which are accommodated in each case in a circumferential opening, which entrainment means in one stage are for their part connected partly to the driving disk and partly to the cover disks which accommodate the latter between them and in another stage are mounted for movement in the circumferential direction so as to permit torque transmission from the driving disk to the driven disk and furthermore damped relative movements between these disks and the cover disks and hence thus also between the driving disk and the driven disk.
The object of the present invention consists on the contrary in the provision of a vibration damper which is of simplified construction, but in particular however will also ensure a more effective suppression of periodic stimuli that give rise to torsional vibrations. This problem is solved in a torsional vibration damper of the kind referred to above in that between the driving disk and the cover disks on the one hand and between the latter and the driven disk on the other hand a friction stage is provided in each case which becomes operative when relative movements occur between these disks.
With the invention, it is a question of a damping effect brought about by the friction stages being superimposed on the vibration damping produced by the damping springs, which naturally leads to a rapid dying away of vibration stimuli and hence to a reduction in torsional vibrations at the moment when they originate.
According to a development feature of the invention, the damping springs of each individual group are arranged in parallel with one another, whereas the groups are in series with each other, so that when angular displacements occur between the driving disk and the driven disk, the spring groups associated with these two disks cooperate with each other. Since, with a series connection, the resulting characteristic line has a flatter course than the characteristic lines of the individual springs which form part of the series connection, substantial angular displacements can be obtained in this way with only small torques.
Moreover, it is advantageous if the damping springs of each individual group have equal spring tempers. However, in a further construction of the invention, the damping springs of various different spring groups have different spring tempers.
By suitably arranging the damping springs in the individual groups in regard to the spring travel obtainable and the spring temper, it is possible to obtain from a predetermined angular displacement between the driving disk and the driven disk a characteristic line the course of which is altered as compared with the initial range. This may be achieved by the cooperation of the damping springs of the several groups being discontinued after a predetermined rotational angle has been attained.The cooperation of the damping springs which operate in a series connection in an initial rotational angular range may for example be discontinued as a result of the damping springs of the one group being completely compressed after a predetermined angular range of rotation, so that then only the damping springs of the other groups can permit a relative movement between the associated disk and the cover disks and hence a further angular rotation between the driving disk and the driven disk. Naturally, what matters as regards rendering the damping springs inoperative before this second angular range of rotation is exclusively the characteristic line of the damping springs which are then still taking part in the angular rotation.
Another constructional possibility consists in limiting the relative mobility of the driving disk and/or the driven disk with respect to the cover disks to a predetermined rotational angle by means of a stop which acts in the circumferential direction, whereby when this stop becomes operative in the appropriate direction of rotation a rotationally rigid connection takes place between the associated disk and the cover disks and consequently the damping springs which operate between these means are put out of operation.
If, however, according to another constructional feature of the invention, the damping springs of at least one spring group are prestressed, the formation of decreasing characteristic line courses is obtained. The damping springs of the one group, which are not stressed or are only very weakly stressed, are then at first in operation alone in an initial angular range of rotation and determine the course of the torque in dependence on the rotational angles that occur corresponding to their own spring temper. As soon as the spring force of the damping springs of this group of springs, due to compression, attains the prestress of the damping springs of the next group, the springs of both groups operate in series and the attainable rotational angles result as the sum of the rotational angles which occur at the individual spring groups.The characteristic line of the torque in dependence on the rotational angles thus has a flat course, so that the characteristic line of the entire arrangement, in the range of angular rotation in which the damping springs of both groups cooperate, has a decreasing course compared with the initial range of angular rotation in which only the non-prestressed damping springs of the first-mentioned spring group were operative
In yet another construction of the invention, the torsional vibration damper may also be provided with a third damping group in such a manner that a group of damping springs is provided which becomes operative only after a predetermined rotational angle has been attained between the driving disk and the cover disks or between the latter and the driven disk, so that after the predetermined rotational angle has been attained, these additional damping springs are connected in parallel with the damping springs of the spring group which is then still operative, which naturally leads to a substantial increase in the torsional stiffness and hence to a steeper course of the torque line in dependence on the angle of rotation.
Moreover, the arrangement may advantageousiy be such that the damping springs of the spring group, which becomes operative only after a predetermined angle of rotation has been attained, are connected to the cover disks so as to be fixed for rotation therewith and are accommodated in arcuate openings which, in the driving disk or driven disk, extend outwardly in both circumferential directions a certain distance beyond the length of the said damping springs of this group.As regards the accommodation in circumferential openings which extend circumferentially in both directions beyond the lengths of the springs, the said damping springs come into contact with the edges which limit the arcuate slots in the circumferential direction only after the free spaces between the said damping springs and the said edges have been traversed, the said edges then acting as abutments for the springs and the latter being connected in parallel with the damping springs of the spring groups which are still operative.
Another constructional feature of the invention consists in the fact that, between the driving disk and the cover disks and/or between the latter and the driven disk, there is provided a load friction stage which becomes operative only after a predetermined rotational angle has been attained, which load friction disk may be capable of limited axial movement between the disks that are movable circumferentially relatively to each other and may be mounted for rotation in a friction-free manner through a predetermined circumferential angle with respect to one of these disks, the arrangement being such that, after having been carried along through the friction-free rotatable region, the friction disk than becomes fixedly connected with the said disk, which in this case may for example be a question of a driven disk.
in a likewise further construction of the invention, a friction stage may also be provided which is operative directly between the driving disk and the driven disk, so that, when relative rotations occur in addition to the friction influences between the driving disk and the cover disks on the one hand and between the latter and the driven disk on the other hand, the direct friction between the driving disk and the driven disk is added.
In a constructional embodiment of the torsional vibration damper according to the invention, a friction ring, which is pressed against at least one friction surface of the disks that are circumferentially movable relatively to each other, is provided in each friction stage. In at least one friction stage, this friction ring may be pressed by means of a pressure disk, which is mounted so as to be capable of limited axial movement, against the friction surface of one of the disks that are movable relative to each other in the circumferential direction, while the pressure disk is loaded by spring force and is mounted so as to be fixed for rotation on the other of the disks that cooperate during the friction stage. A diaphragm spring may serve in each case for pressing against the pressure disk on the friction disk.
A number of embodiments of the invention will be explained hereinafter with the aid of the annexed drawings. In diagrammatic views:- Figure 1 shows in a partial front elevation a first embodiment of a torsional vibration damper according to the invention with three damping stages,
Figure 2 shows a sectional view of the torsional vibration damper taken on the section line Il-Il in
Figure 1,
Figure 3 shows, in a characteristic line diagram, the courses of the torque in dependence on the rotational angles for the tension and thrust sides,
Figure 4 shows an elevation, as in Figure 1, of a second embodiment of a torsional vibration damper which also has three stages,
Figure 5 shows a section taken on the section line V-V through the torsional vibration damper according to Figure 4,
Figure 6 shows a characteristic line diagram similar to Figure 3 of the torsional vibration damper according to Figures 4 and 5,
Figure 7 shows, also in an elevation as in
Figures 1 and 4, a further embodiment of a torsional vibration damper according to the invention which, however, has only two stages,
Figure 8 shows the torsional vibration damper according to Figure 7 in a sectional view taken on the section line VIll-VIll and
Figure 9 shows, in a view as in Figure 6, a characteristic line diagram for the embodiment according to Figures 7 and 8.
In the torsional vibration damper, shown in
Figures 1 and 2 and indicated as a whole by 10, a driving disk 12 is in rotationally rigid driving connection with a driving member 11 which is shown only in broken lines and is of no interest here. The driving disk is accommodated between axially spaced apart cover disks 13, 14 which are rigidly interconnected both rotationally and axially.
The interconnection of the cover disks is obtained by means of distance bolts 1 5 which are riveted to the latter and which are arranged near the outer edge of the cover disks in positions distributed around the circumference and furthermore extend through arcuate slots 16 in the driving disk 12.
The distance bolts 1 5 can move within the circumferential extent of the said slots 16 and hence the cover disks 13, 14 and the driving disk 12 can rotate relatively to each other, as will be explained in greater detail below.
Damping springs 20 are received in circumferential openings 17, 18, 19 located in mutually corresponding circumferentially spaced apart positions in the cover disks 13, 14 on the one hand and in the driving disk 1 2 on the other hand, these openings being circumferentially offset with respect to the slots 1 6 through which the distance bolts 1 5 extend. The driving disk 12 and the cover disks 13, 14 are supported in relation to each other in the circumferential direction by means of these damping springs 20.
The damping springs 20 are moreover held in the circumferential openings in the driving disk 12 and the cover disks 13, 14 by the fact that outer margins of the circumferential openings 17, 18 in the cover disks are set outwardly and engage over at least parts of the damping springs. Radially inwardly of the damping springs, friction rings 22, 23 are arranged on both sides of the driving disk, which friction rings produce a first friction stage and together with the damping springs 20, which are arranged in circumferentially spaced apart positions, form a first damping stage.The friction ring 23 cooperates directly with an inner friction surface of the inner cover disk 14, while the other friction ring 22, which is supported via a pressure disk 24, which in turn is connected to the cover disks 13, 14 so as to be fixed for rotation therewith but capable of limited axial movement with respect to them, is pressed by a diaphragm spring 25 which is supported against the outer cover disk 13, against the driving disk. The pressure disk 24 has in the region of distance bolts 15, which interconnect the cover disks so that they are axially and rotationally rigid with each other, radially outwardly extending portions 26 which engage partly round the distance bolts as shown in Figure 1.
Radially inwardly of the driving disk 12 and coaxial therewith, a driven disk 30 is arranged between the cover disks 1 3, 1 4, which driven disk 30 has on the hub side a rotationally fixed connection via an inner set of teeth 32, which is of no further interest at this stage, with a corresponding outer set of teeth 33 on a driven shaft 34 which is indicated only in chain-dotted lines in Figure 2.Damping springs 40, which once again are operative in the circumferential direction are arranged in circumferentially spaced apart positions in an inner annular region and are accommodated in mutually corresponding openings 36, 37, 38 in the cover disks 13, 14 on the one hand and the driven disk 30 on the other hand, these damping springs 40 being held in their positions by outwardly bent parts of the outer margins of the circumferential openings in the cover disks. The driven disk 30 and the cover disks 13, 14 are resiliently supported with respect to each other in the circumferential direction by means of these inner damping springs 40. In a manner similar to that in the case of the driving disk, friction rings 42, 43 are arranged in the hubadjacent marginal region of the driven disk on both sides of the latter.While the friction ring 42 acts cirectly between the driven disk and a corresponding friction surface of the front cover disk 13, the friction ring 43 is pressed by a pressure disk 44, which is mounted so as to be capable of limited axial movement and has a rotatably fixed connection with the cover disks, against the other side of the driven disk 30. The bearing pressure is applied by means of a diaphragm spring 45 which in turn is supported against a load friction disk 48 which will be described below in connection with a third damping stage.
The load friction disk 48 is arranged coaxially with respect to the driven disk 30 and has a limited range of axial movement between the latter and the inner cover disk 14. In the region of the circumferential openings in the driven disk 30 and the cover disks 13, 14 which receive the damping springs 40 of the second damping stage, there are also circumferential openings 49 in the load friction disk 48, the circumferential extent of which is, however, greater than in the case of the circumferential openings in the driven disk and the cover disks, so that the load friction disk can move through a certain circumferential distance with respect to the said disks without the damping springs 40 coming into contact with the circumferential limits of these circumferential openings 49. This load friction disk 48 forms together with two damping springs 50 a third damping stage. These two damping springs are received symmetrically in relation to each other in each case between numbers of damping springs 40 of the second damping stage in further circumferential openings 51, 52 in the cover disks 1 3, 1 4 and each extend through corresponding individual circumferential openings 53, 54 in the driven disk 30 and the load friction disk 48.The circumferential openings 53, 54 in the driven disk 30 and the load friction disk 48 extend circumferentially beyond the corresponding extent of the damping springs 50, so that the damping springs 50 come into contact with the circumferential limits of the circumferential openings 53 in the driven disk 30 only after a predetermined rotation of the driven disk 30 with respect to the cover disks 1 3, 1 4 and consequently only become operative after the said predetermined rotational angle has been completed.
Between the load friction disk 48 and an inner friction surface of the inner cover disk 14 there is arranged a friction ring 56. As regards the situation between the load friction disk and the pressure disk 44 belonging to the second friction stage, which pressure disk 44 has a rotationally fixed connection with the cover disks via axially directed tongues 46 positively engaged in circumferential recesses in the inner cover disk 14, the load friction disk 48 is pressed against the friction ring 56 and the latter is pressed in turn against the corresponding friction surface of the inner cover disk 14.The load friction disk 48 is, however, freely rotatable with respect to the driven disk 30 through a predetermined circumferential range, since axially directed tongues 57 of the load friction disk engage in the circumferential openings 53 in the driven disk 30, which circumferential openings extend beyond the damping springs 50 in both directions. The tongues 57, after a predetermined rotation of the load friction disk with respect to the driven disk, come into contact with stops and then provide a rotationally fixed connection of the load friction disk with the driven disk in the direction of rotation at the time concerned. The damping springs 50 form, together with the load friction disc 48 and the associated friction surface of the friction ring 56, the third damping stage.
When, during operation of the torsional vibration damper 10 a torque is fed in from the driving part 11 via the driving disk 12, this leads to a rotation between the driving disk and the cover disks 13, 14 on the one hand and between the latter and the driven disk 30 on the other hand which is fixed for rotation with the driven shaft 34.
The damping springs 20 and 40 of the first and second damping stages, which are assembled without being prestressed, then operate in series with a correspondingly soft spring characteristic.
This is shown by the flat course of the characteristic line 60 in the graph according to
Figure 3. Naturally the greater rotation takes place in the region of that damping stage the springs of which have the lowest hardness. In the present case, this is the damping stage which operates between the driving disk 1 2 and the cover disks 13, 14 with the damping springs 20.As soon as the damping springs 20 of this stage have, due to the rotation of the driving disk 12 with respect to the cover disks 13, 14 undergone such a compression that the distance bolts 15, which interconnect the two cover disks so that they are rotationally and axially fixed to each other, come to bear against the ends of the arcuate slots 1 6 in the driving disk, the damping springs of the first stage are put out of action and only the damping springs of the second stage are operative.In the graph according to Figure 3, the first damping stage extends over the angular rotational range of 0 to 230 and, after the putting out of action of the first damping stage; a further relative rotation takes place between the driven disk 30 and the cover disks 13, 14 in the range of the second damping stage between 230 and 380, in which only the damping springs 40 are operative, and this leads to an ascending reach of the characteristic line 61 in the region of the second damping stage.At a rotational angle of 380 between the driving disk 12 and the driven disk 30, the damping springs 50 of the third damping stage come to lie against the circumferential limits of the window-like circumferential openings 53 in the driven disk, as a result of which the damping springs 50 of the third stage become operative in parallel with the damping springs 40 of the second damping stage. This parallel arrangement of the damping springs 40 of the second stage with the damping springs 50 of the third damping stage naturally leads to a steep rise of the characteristic line 62 which joins the characteristic line 61 of the second damping stage at a rotational angle of 38 and is operative up to a total blocking of the damping springs of the second and third stages at a rotational angle of 42".
In addition to the manner described above in which the damping springs come into operation when rotational angles are present between the driving disk 12 and the cover disks on the one hand and between the latter and the driven disk on the other hand, the friction stages associated with each damping stage also operate corresponding to the relative movements of the driving disk and the driven disk with respect to the cover disks.Thus, within the range of the first damping stage with the relatively soft damping springs 20 during the initial rotation in particular, a relative rotation occurs between the driving disk 12 and the cover disks 13, 14, so that in particular frictional work is performed in the region of the friction rings 22, 23. When, after a predetermined rotational angle has been attained between the driving disk 12 and the cover disks 13, 14, the distance bolts 1 5 which interconnect the cover disks 13, 14 come up against the ends of the arcuate slots 1 6 and thus prevent a further relative movement between the driving disk 12 and the cover disks, the frictional work which is done during continued angular rotation is first performed only in the region of the friction rings 42, 43 which form the second friction stage. The load friction disk 48 is, as during the rotation of the driving disk 12 with respect to the cover disks 13, 1 4, stationary with respect to the cover disks until the axially directed tongues 57 which engage in the circumferential opening 53 come into contact with stops within the said circumferential opening by means of which rotational mobility of the load friction disk with respect to the driven disk 30 is limited.After the engagement of the tongues 57 of the load friction disk with the said stops, the third friction stage becomes operative, in that the load friction disk, which has a positive frictional connection via the friction ring 56 with a corresponding friction surface of the inner cover disk 14, carries out a relative rotation with respect to the said inner cover disk. The frictional work performed in the region of the friction disk 56 of the third friction stage is therefore superimposed on the frictional work which is done in the region of the second friction stage. It is apparent and shown on the traction side of the graph according to Figure 3 that, when torques are reduced and corresponding reverse rotations of the disks which are movable with respect to each other take place, the same frictional work must be performed.
Relationships basically equal to those for the traction side of the graph hold good for the thrust side which is merely indicated.
In the embodiment according to Figures 4 and 5, it is likewise a question of a three-stage torsional vibration damper in which, for parts which are the same as in Figures 1 and 2, the same reference marks have been used but increased by one hundred in order to distinguish them.
A driving disk 11 2, which is accommodated between cover disks 113, 114 that are interconnected so as to be fixed together axially and rotationally, serves once again for the introduction of a torque from a driving part 111 indicated only in broken lines. A driven disk 130, which is arranged coaxially with respect to the driving disk 112 and extends radially inwardly therefrom and which is also accommodated between the cover disks, serves for the transmission of torque to a driven shaft which is not further shown. Instead of this driven disk being provided on the edge nearer the hub with a simple set of spur gear teeth 132, which meshes with a corresponding set of gear teeth on the driven shaft, a hub flange 131 may be formed on the driven disk in the hub region of the latter with a corresponding set of broached teeth 132'.
As in the first embodiment, damping springs 120, 140 are accommodated in corresponding circumferential openings 1 117, 11 8, 119and 136, 137, 138 in the driving disk 112 and the cover disks 113, 114 on the one hand and in the driven disk 1 30 and the cover disks on the other hand, which damping springs provide a support in the circumferential direction both for the driving disk and also for the driven disk with respect to the cover disks. Unlike the first embodiment, the first damping stage is, however, associated with the driven disk 130, while the second damping stage is associated with the driving disk 11 2.
Accordingly, a total of four damping springs 1 40 of the first damping stage are accommodated in the circumferential openings 136, 137, 138 of the cover disks 113, 114 and the driven disk 130, which circumferential openings are arranged so that they are uniformly distributed around the circumference, while, in the region of the driving disk 112, three damping springs 120 of the second stage are arranged in each of the two halves. In each case, damping springs 1 50 of a third stage are arranged between the groups of three damping springs 120 of the second stage in corresponding circumferentially extending openings 151,152 in the cover disks 113,114 and extend through window-like circumferential openings 1 53 in the driving disk 112.These arcuate circumferential openings 1 53 in the driving disk 112 extend substantially beyond the lengths of the damping springs 1 50 of the third stage so that the latter become operative in parallel with the damping springs 120 of the second stage in one direction or the other only when the driving disk 112 has completed such a rotation, while the damping springs 1 20 of the second stage are being compressed, that the damping springs 1 50 of the third stage come into contact with the circumferential limits of the arcuate circumferential openings 1 53 in the driving disk.
Just as in the first embodiment, the damping springs of the first and second damping stages are connected in series during the initial phase of a rotation occurring between the driving and driven disks, so that the rotation of these disks which takes place under load opposes the total resultant of this series connection. The combined working range of the damping springs of the first and second stages extends in this embodiment up to a rotational angle of 32 . This is shown by the characteristic line 1 60 in Figure 6.Moreover, the comparatively soft damping springs of the first stage undergo a preponderant compression until the distance bolts 115, which are movable circumferentially in the arcuate slots 11 6 in the driven disk 130 and by means of which the cover disks 113, 114 are axially and rotationally rigidly connected together, reach the ends of the said slots and thereby lock the driven disk with respect to the cover disks in the direction of rotation at the time concerned. The first stage is thus brought to rest and further angular rotational movements can therefore continue to take place only between the driving disk 112 and the cover disks. As regards the above-described cutting out of the damping springs 140 of the first stage, only the damping springs 120 of the second stage still oppose an angular rotation starting from about 320 until, after reaching a rotational angle of about 380, the damping springs 1 50 of the third stage become connected in parallel with the damping springs 120 of the second stage. Accordingly, the characteristic line 1 61 of the second stage is fixed between 320 and 380 regardless of the spring temper of the damping springs 120 of the second stage. The characteristic line 1 62 of the third stage has by contrast a steep rising slope which is caused by the effective parallel connection which then exists between the damping springs 120 and 1 50 of the second and third stages and the spring resultant which is then produced as the sum of the individual spring constants.
Also, in the second embodiment, friction is superimposed on the spring actions in the individual damping stages. Unlike the first embodiment, however, only in a radial overlapping region between the driving disk 112 and the driven disk 1 30 is there located a friction ring 1 22 which is pressed against the driving disk 11 2 via a pressure disk 124 connected to the driven disk 130 for axial movement therewith, by means of a diaphragm spring 125 acting between the pressure disk 124 and the driven disk 130.
Moreover, the arrangement may be such that, in the region of its outer margin between the driving disk and the cover disks and in the vicinity of the hub region between the driven disk and the cover disks, friction is operative when the said disks perform a rotation with respect to the cover disks.
Unlike the first embodiment, no additional load friction disk is provided in this embodiment which is first operative in the third damping stage and can also be put into practice in the embodiment so that, in dependence on the limitation of its rotational mobility with respect to the driven disk, the friction action may either precede or follow the coming into operation of the damping springs of the third stage, so that a so-called "delayed friction" can be produced.
In the third embodiment shown in Figures 7 and 8, it is a case of a two-stage torsional vibration damper, in which once again the same reference marks have been used for the same parts as in the previous embodiments, but have been increased once again by a hundred in order to distinguish them.
In this embodiment also, the introduction of the load takes place from a driving part 211, which is shown only in broken lines, via a driving disk 212, which once again is accommodated between cover disks 213, 214 which are interconnected so as to be rotationally and axially fixed with respect to each other. Radially inwardly of the driving disk 212 there is located between the cover disks a driven disk 230 provided with a hub portion 231, which is rotationally fixedly connected, in a manner the details of which are not of interest here, with a driven shaft 234 which is also only indicated in broken lines.In conformity with the second embodiment, the damping springs 240 of the first damping stage are accommodated in an inner annular region in the zone between the driven disk 230 and the cover disks 213,214 in
mutually corresponding circumferential recesses 236,237,238 in the said disks 213,214 and 230.The rotatability of the driven disk with
respect to the cover disks is limited by the distance bolts 21 5 which interconnect the cover
disks so that the latter are axially and rotatably fixed with respect to each other and which extend through arcuate slots 216 in the driven disk and, after a predetermined rotational angle has been attained between the driven disk 230 and the cover disks 213, 214, come to lie against the circumferential limits of the said slots, so that a rotationally fixed connection is produced in the direction of rotation which obtains at the time concerned between the driven disk and the cover disks and consequently the damping springs 240 of the first stage are inoperative.The damping springs 220 of the second damping stage are, as in the embodiment according to Figures 4 and 5, operative between the driving disk 212 and the cover disks 213, 214, but unlike the second embodiment are, however, fitted under prestress.
As regards the prestressing of the damping springs 220, the second damping stage comes under load first of all, only so long as there is rotation between the driven disk 230 and the cover disks 213, 214, until the spring force of the damping springs 240 of the first stage, due to the compression, attains a value corresponding to the prestressing force of the damping springs 220 of the second stage. Since therefore, during the initial rotation, only the damping springs 240 of the first stage are operative, the course of the characteristic line 260, shown in Figure 9, in the region between 0 and about 3 is also determined only by the spring temper of the damping springs 240 of this stage.During a continued angular rotation between the driving disk 212 and the driven disk 230, the damping springs 220 of the second stage become added in series with the damping springs 240 of the first damping stage, with the result that the spring force which results from the series connection is operative.Since the spring characteristic which results substantially from the series connection has a flatter shape than the individual characteristics of the damping springs 220, 240 of the two stages, the angular rotation which extends beyond a rotational angle of about 30 is therefore determined by the manifestly flatter course of the characteristic line 261 which can be seen in Figure 9 and which, in the embodiment shown, extends to about 140. By the use of prestressed damping springs in one of the damping stages a descending slope of the characteristic line can be produced.
The series connection of the damping springs of the first and second stages, on continued angular rotation between the driving disk 212 and the cover disks 213, 214, is terminated at a rotational angle of about 140 by stops which are operative between the said disks, since a rigid connection then occurs, in the direction of rotation obtaining at that time, between the driving disk and the cover disks.After the cutting out of the damping springs 220 of the second stage which is effected in this manner, a further angular rotation can only take place against the action of the damping springs 240 of the first stage which were operative alone during the initial rotational range, in fact until stops that are operative between the cover disks and the driven disk come into engagement and thereby also connect the driven disk with the cover disks in the direction of rotation which obtains at that time. These stops consist of the distance bolts 21 5 which axially and rotationally fixedly interconnect the cover disks 213,214 and which extend through the arcuate slots 21 6 in the driven disk 230.In Figure 9, the steeply rising section 262 of the characteristic line, which adjoins the flat middle section 261 of the characteristic line, shows the operational condition after the locking of the rotational mobility of the driving disk with respect to the cover disks.
Also, in this embodiment, a friction ring 222 is arranged in an overlapping region between the driving disk 212 and the driven disk 230 and likewise a friction ring 223 between the driving disk and the inner cover disk 214. A further friction ring 242 is located radially inwardly of the damping springs 240 of the first damping stage, lying against the driven disk 230, which friction ring 242 is pressed by means of a diaphragm spring 245 via a pressure disk 244 which is connected to the outer cover disk so as to be fixed for rotation therewith. It is thus apparent that, on a rotation of the driven disk 230 with respect to the cover disks 213,214, friction will occur against the cover disks 213, 214 in the region of the friction ring 242 nearer the hub which acts on the driven disk, as well as in the region of the friction ring 222 between the driven disk 230 and the driving disk 212.As the second friction stage, friction occurs, on rotation of the driving disk 212 with respect to the cover disks 21 3, 214, in the region of the friction ring 223 which is operative between the driving disk and the rear cover disk 214, and likewise, when angular rotation occurs, between the driving disk and the driven disk, in the region of the friction ring 222 which operates between these two disks. In the working range identified by the steeply rising section 262 of the characteristic line, in the region between 140 and 1 5.50, friction occurs in the region of the friction ring 222 accommodated between the driving disk and the driven disk and in the region of the friction ring 242 on the driven side and nearer the hub. It is clear therefore that, in all operative ranges of the torsional vibration damper, friction is superimposed on the operation of the damping springs.
Claims (14)
1. Torsional vibration damper, especially for motor vehicles fitted with torque converters, with a driving disk and a driven disk each accommodated between cover disks which in turn are connected together so as to be axially and rotationally rigid with each other, which driving and driven disks are movable circumferentially relatively to each other and from time to time with respect to the cover disks, as well as being supported circumferentially against the latter independently of each other via respective groups of damping springs which act circumferentially from time to time and are accommodated in circumferentially distributed, circumferentially extending openings in the cover disks on the one hand and in the driving and driven disks on the other hand, characterised in that between the driving disk (12, 112, 212) and the cover disks (13,14;; 113,114; 213,214) on the one hand and between the latter and the driven disk (30, 1 30, 230) on the other hand a friction stage is provided in each case which becomes operative when relative movements occur between these disks.
2. Torsional vibration damper according to claim 1, characterised in that the damping springs (20, 40, 50; 120, 140, 150, 220, 240) of each individual group are arranged in parallel with one another, the groups however being connected in series with each other.
3. Torsional vibration damper according to claim 1 or 2, characterised in that the damping springs (20, 40, 50; 120, 140, 150; 220, 240) of each individual group have spring tempers which are equal to one another.
4. Torsional vibration damper according to one of claims 1 to 3, characterised in that the damping springs (20, 40, 50; 120, 140, 150; 220, 240) of various groups of springs have different spring tempers.
5. Torsional vibration damper according to one of claims 1 to 4, characterised in that the relative mobility of the driving disk (12, 112, 212) and/or the driven disk (30, 130, 230) with respect to the cover disks (13,14; 113,114; 213,214) is limited to a predetermined rotational angle by means of at least one stop (15, 16; 115, 116; 215,216) which acts in the circumferential direction.
6. Torsional vibration damper according to claim 5, characterised in that the stop (15, 115, 215) is rigidly connected to the cover disks and engages in an arcuate recess (16, 116, 216) in the driving disk (12, 112, 212) and/or in the driven disk (30, 130, 230), which recess extends over a predetermined circumferential angle.
7. Torsional vibration damper according to claim 6, characterised in that the stop is a bolt (1 5, 115, 215) extending axially through the arcuate recess (16, 116, 216) in the driving disk (12, 112,212) or the driven disk (30, 130,230) and interconnecting the cover disks.
8. Torsionai vibration damper according to one of claims 1 to 7, characterised in that the damping springs (20, 120, 220) or (40, 140, 240) of at least one group of springs are prestressed.
9. Torsional vibration damper according to one of claims 1 to 8, characterised in that a group of damping springs (50, 1 50) is provided which becomes operative only after a predetermined angle of rotation has been attained between the driving disk (12, 112) and the cover disks (13, 14; 113, 114) or between the latter and the driven disk (30, 130).
1 0. Torsional vibration damper according to claim 9, characterised in that the damping springs (50, 1 50) of the group of springs which becomes operative only after a predetermined angle of rotation has been attained are connected to the cover disks so as to be fixed for rotation therewith and are accommodated in arcuate openings (53, 153) which, in the driving disk (12,112) or driven disk (30, 130), extend outwardly in both circumferential directions a certain distance beyond the length of the damping springs of this group.
11. Torsional vibration damper according to one of claims 1 to 10, characterised in that there is provided between the driving disk (12) and the cover disks and/or between the latter and the driven disk (30) a load friction stage which becomes operative only after a predetermined angle of rotation has been attained.
12. Torsional vibration damper according to one of claims 1 to 11, characterised in that a friction stage is provided which is operative directly between the driving disk (112,212) and the driven disk (130, 230).
1 3. Torsional vibration damper according to one of claims 1 to 12, characterised in that a friction ring (22, 23,42, 43, 56; 122; 222, 223, 242), which is pressed against at least one friction surface of the disks which are circumferentially movable relatively to each other, is arranged in each friction stage.
14. Torsional vibration damper according to claim 13, characterised in that, in at least one friction stage, the friction ring is pressed, by means of a pressure disk (24, 44, 48; 124; 244) which is mounted so as to be capable of limited axial movement, against the friction surface of one of the disks which are movable relatively to each other in the circumferential direction, while the pressure disk is loaded by spring force and is mounted, so as to be fixed for rotation, on the other of the disks which cooperate during the friction stage.
1 5. Torsional vibration damper according to claims 11 and 13, characterised in that the load friction stage comprises a spring-loaded friction disk (48) which is axially movable between the disks that are movable relatively to each other in the circumferential direction and is mounted opposite one of these disks so as to be rotatable without friction through a predetermined circumferential angle, but, after the predetermined circumferential angle has been traversed, is connected with this disk so as to be fixed for rotation therewith in the direction of rotation obtained at the time concerned.
1 6. Torsional vibration damper according to claim 14 or 15, characterised in that a diaphragm spring (25, 45; 125; 245) serves in each case for pressing against the pressure disk or the friction disk.
1 7. A torsional vibration damper substantially as hereinbefore described with reference to
Figures 1 to 3, Figures 4 to 6 or Figures 7 to 9 of the drawings.
1 8. A power transmission system including a torque converter and a damper according to any of the preceding claims.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE19823227809 DE3227809A1 (en) | 1982-07-24 | 1982-07-24 | TORQUE Vibration DAMPER, ESPECIALLY FOR MOTOR VEHICLE DRIVERS EQUIPPED WITH TORQUE CONVERTERS |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB8320027D0 GB8320027D0 (en) | 1983-08-24 |
| GB2124334A true GB2124334A (en) | 1984-02-15 |
| GB2124334B GB2124334B (en) | 1986-01-08 |
Family
ID=6169319
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB08320027A Expired GB2124334B (en) | 1982-07-24 | 1983-07-25 | Torsional vibration damper especially for motor vehicle drives provided with torque converters |
Country Status (5)
| Country | Link |
|---|---|
| JP (1) | JPS5934024A (en) |
| BR (1) | BR8303924A (en) |
| DE (1) | DE3227809A1 (en) |
| FR (1) | FR2530752A1 (en) |
| GB (1) | GB2124334B (en) |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2573150A1 (en) * | 1984-11-09 | 1986-05-16 | Valeo | TRANSMISSION ASSEMBLY, ESPECIALLY FOR A MOTOR VEHICLE, HYDRAULIC COUPLING DEVICE COMPRISING SUCH A TRANSMISSION ASSEMBLY, A MOTION-TAKING DEVICE COMPRISING THE CONSTITUTION THEREOF, AND A METHOD FOR CARRYING OUT SAID MOTION-TENSIONING DEVICE |
| FR2579709A1 (en) * | 1985-03-27 | 1986-10-03 | Luk Lamellen & Kupplungsbau | COMPENSATING DEVICE FOR A-ROTATION RINGS |
| FR2580050A1 (en) * | 1985-04-04 | 1986-10-10 | Luk Lamellen & Kupplungsbau | |
| FR2593574A1 (en) * | 1985-09-07 | 1987-07-31 | Luk Lamellen & Kupplungsbau | Mechanism for compensating for rotational jolts, especially in internal combustion engines |
| US4716998A (en) * | 1985-04-30 | 1988-01-05 | Aisin Warner Kabushiki Kaisha | Direct coupling clutch with a damper device for a fluid coupling |
| FR2631409A1 (en) * | 1983-11-15 | 1989-11-17 | Luk Lamellen & Kupplungsbau | DEVICE FOR COMPENSATING ROTATION A-KITS |
| GB2271411A (en) * | 1992-10-12 | 1994-04-13 | Luk Lamellen & Kupplungsbau | Torque converter etc.with damper assembly |
| FR2700191A1 (en) * | 1986-07-05 | 1994-07-08 | Luk Lamellen & Kupplungsbau | Device for damping vibrations. |
| FR2794203A1 (en) * | 1986-07-05 | 2000-12-01 | Luk Lamellen & Kupplungsbau | OSCILLATION DAMPING DEVICE |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4576259A (en) * | 1984-05-29 | 1986-03-18 | Eaton Corporation | Torsion damping mechanism with variable damping |
| JPH07103926B2 (en) * | 1985-04-30 | 1995-11-08 | アイシン・エィ・ダブリュ 株式会社 | Fluid transmission |
| DE3745090C2 (en) * | 1986-07-05 | 2002-03-07 | Luk Lamellen & Kupplungsbau | Flywheel with torsional vibration damping |
| DE19544832C2 (en) * | 1995-12-01 | 1998-01-22 | Patentverwertung Ag | clutch |
| JPH10153238A (en) * | 1996-11-14 | 1998-06-09 | Patentverwert G Rohs Voigt Mbh | Fluid type twisting vibration damping device |
| DE112007000913A5 (en) | 2006-05-04 | 2009-01-15 | Luk Lamellen Und Kupplungsbau Beteiligungs Kg | Torque transfer device |
| FR3053424B1 (en) * | 2016-07-01 | 2018-07-27 | Valeo Embrayages | TORSION DAMPER |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1406070A (en) * | 1971-11-29 | 1975-09-10 | Ferodo Sa | Clutch assembly |
| GB2084698A (en) * | 1980-09-25 | 1982-04-15 | Daikin Mfg Co Ltd | Damper disc |
| GB2093565A (en) * | 1981-02-25 | 1982-09-02 | Valeo | Torsion damping device for an automotive clutch plate assembly |
| GB2098702A (en) * | 1981-05-20 | 1982-11-24 | Ford Motor Co | Compound damper assembly for an automatic transmission |
| GB2109085A (en) * | 1981-11-14 | 1983-05-25 | Fichtel & Sachs Ag | Clutch disc with torsional vibration damper |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR1520684A (en) * | 1967-03-02 | 1968-04-12 | Ferodo Sa | Improvements to the clutch friction discs with damper hubs |
| JPS5259860U (en) * | 1975-10-29 | 1977-04-30 | ||
| FR2386729A1 (en) * | 1977-04-04 | 1978-11-03 | Ferodo Sa | TORSION DAMPER, IN PARTICULAR CLUTCH FRICTION, ESPECIALLY FOR MOTOR VEHICLES |
| SE431214B (en) * | 1977-06-02 | 1984-01-23 | Klaus H Mosbach | SET TO MAKE MAGNETIC POLYMER PARTICLES BASED ON A PREFERRED BIOLOGY ACTIVE SUBSTANCE |
| FR2456264A1 (en) * | 1979-05-11 | 1980-12-05 | Ferodo Sa | TORSION DAMPING DEVICE, IN PARTICULAR A CLUTCH FRICTION, IN PARTICULAR FOR A MOTOR VEHICLE |
| CA1157398A (en) * | 1979-12-26 | 1983-11-22 | Paul E. Lamarche | Two-stage torsional vibration damper |
-
1982
- 1982-07-24 DE DE19823227809 patent/DE3227809A1/en not_active Ceased
-
1983
- 1983-07-22 FR FR8312156A patent/FR2530752A1/en not_active Withdrawn
- 1983-07-22 BR BR8303924A patent/BR8303924A/en unknown
- 1983-07-25 JP JP13452783A patent/JPS5934024A/en active Granted
- 1983-07-25 GB GB08320027A patent/GB2124334B/en not_active Expired
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1406070A (en) * | 1971-11-29 | 1975-09-10 | Ferodo Sa | Clutch assembly |
| GB2084698A (en) * | 1980-09-25 | 1982-04-15 | Daikin Mfg Co Ltd | Damper disc |
| GB2093565A (en) * | 1981-02-25 | 1982-09-02 | Valeo | Torsion damping device for an automotive clutch plate assembly |
| GB2098702A (en) * | 1981-05-20 | 1982-11-24 | Ford Motor Co | Compound damper assembly for an automatic transmission |
| GB2109085A (en) * | 1981-11-14 | 1983-05-25 | Fichtel & Sachs Ag | Clutch disc with torsional vibration damper |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2631409A1 (en) * | 1983-11-15 | 1989-11-17 | Luk Lamellen & Kupplungsbau | DEVICE FOR COMPENSATING ROTATION A-KITS |
| FR2573150A1 (en) * | 1984-11-09 | 1986-05-16 | Valeo | TRANSMISSION ASSEMBLY, ESPECIALLY FOR A MOTOR VEHICLE, HYDRAULIC COUPLING DEVICE COMPRISING SUCH A TRANSMISSION ASSEMBLY, A MOTION-TAKING DEVICE COMPRISING THE CONSTITUTION THEREOF, AND A METHOD FOR CARRYING OUT SAID MOTION-TENSIONING DEVICE |
| FR2579709A1 (en) * | 1985-03-27 | 1986-10-03 | Luk Lamellen & Kupplungsbau | COMPENSATING DEVICE FOR A-ROTATION RINGS |
| FR2580050A1 (en) * | 1985-04-04 | 1986-10-10 | Luk Lamellen & Kupplungsbau | |
| US4716998A (en) * | 1985-04-30 | 1988-01-05 | Aisin Warner Kabushiki Kaisha | Direct coupling clutch with a damper device for a fluid coupling |
| FR2593574A1 (en) * | 1985-09-07 | 1987-07-31 | Luk Lamellen & Kupplungsbau | Mechanism for compensating for rotational jolts, especially in internal combustion engines |
| FR2700191A1 (en) * | 1986-07-05 | 1994-07-08 | Luk Lamellen & Kupplungsbau | Device for damping vibrations. |
| FR2794203A1 (en) * | 1986-07-05 | 2000-12-01 | Luk Lamellen & Kupplungsbau | OSCILLATION DAMPING DEVICE |
| GB2271411A (en) * | 1992-10-12 | 1994-04-13 | Luk Lamellen & Kupplungsbau | Torque converter etc.with damper assembly |
| GB2271411B (en) * | 1992-10-12 | 1996-12-04 | Luk Lamellen & Kupplungsbau | Power transfer device |
Also Published As
| Publication number | Publication date |
|---|---|
| FR2530752A1 (en) | 1984-01-27 |
| DE3227809A1 (en) | 1984-01-26 |
| GB8320027D0 (en) | 1983-08-24 |
| BR8303924A (en) | 1984-04-10 |
| JPH0444138B2 (en) | 1992-07-20 |
| GB2124334B (en) | 1986-01-08 |
| JPS5934024A (en) | 1984-02-24 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |