FR2799809A1 - TORSIONAL OSCILLATION DAMPER - Google Patents

Abstract

A torsional oscillation damper comprising a backing member for supporting a resiliently deformable damper element against the primary side or the secondary side of the damper. The support element (76) has a surface region (82) which is placed opposite the sliding surface (78) of the shock absorber and through which the support element moves along this surface sliding (78). The support element (76) comprises in its surface region (82) a segment (92) for resting against the surface (78). This element (76) has a surface such that the distance D between the surfaces (78 and 82) increases in both directions of movement of the element (76) relative to the surface (78).

Description

Description.

  The present invention relates to a torsional oscillation damper comprising a support element for

  supporting an elastically deformable damping element

  be the primary side and / or the secondary side of

  the shock absorber or against another deformed shock absorber element

  elastically ble, the support element having a sur-

  upper face placed on the damper so as to be turned towards a sliding surface, zone by which the support element moves along this sliding surface. According to document DE 41 28 868 there is known a torsional oscillation damper with, between the side

  primary and secondary side, several sets of springs.

  Each set includes several elements of functional springs-

  like damping elements. In the games of res-

  spells, the different elements are pressed against each other in the peripheral direction with interposition of skates. The end zones of the spring sets situated in the peripheral direction, that is to say the ends of the respective springs which are placed there, are supported on spring shoes at the level of the respective stress zones on the primary side or on the secondary side. Both the pads and the spring shoes can be moved to slide in the peripheral direction along a

  sliding surface located radially inside at the

  calf on the primary side or on the secondary side. The area in

  which the spring shoes or shoes can come off

  placing in the peripheral direction is produced in the form of a lubricating agent chamber, sealed so that the sliding movement takes place with the interposition of a lubricating agent between the sliding elements or

respective supporting elements.

  In such support elements in the form of pa-

  tins or spring clogs, the main difficulty is

  that the centrifugal forces generated during operation

  risk of pressing these elements strongly enough

  against the sliding surface and thereby generate

  these increasing friction, opposing the recall of

  the torsional oscillation damper to its new position

  or by creating an additional force component that must be overcome to get out of the neutral position, and achieve the desired movement. This results in problems of

  decoupling and muffled noises up to bat noises

transmission.

  The object of the present invention is to develop a torsional oscillation damper provided with support elements, making it possible to avoid to a very large extent the deterioration of the damping effect which could be

caused by centrifugal force.

  To this end, the invention relates to a damper of the type defined above, characterized in that

  * the support element comprises, in its upper surface area

  upper, a sliding surface segment to lean against the sliding surface, and * this support element is configured at its area of

  top surface so that when the segment is applied

  that against the sliding surface, the distance (D) com-

  taken between the sliding surface and the upper surface area increases from the segment in at least one

  direction of movement of the support element.

  According to another characteristic of the invention, a damper comprises a support element provided in its upper surface area, with a sliding surface segment intended to come into abutment against the sliding surface and

  the support element and configured in its area of sur-

  upper face so that, when the sliding surface segment is applied against the sliding surface, the distance between the sliding surface and the surface area

  upper increases from the sliding surface segment

  towards at least one direction of movement of the support element. So if the element is moved

  along the sliding surface, the lubricating agent

  Fiant being in this zone forcibly passes into the zone in which the support element comes with its sliding surface segment against the sliding surface. We

  thus achieves a sort of hopper by the lubricating agent.

  In such an embodiment, the distance between the

  upper surface area and the increased sliding surface

  preferably lie in both directions of travel from the sliding surface segment. For example, we

  can do this in that the sliding surface segment

  lies in a central area of the element and presses

  essentially for the direction of travel.

  The present invention also relates to a cushioning

  torsional oscillation weaver, in particular for a two-mass flywheel or a clutch disc, comprising

  a primary side and a secondary side which can rotate

  rotation of an axis of rotation relative to the primary side against

  the action of a damping device, the damping device

  seur comprising at least one unit with damping elements which can bear in their peripheral end zone against respectively a bearing zone on the primary side and on the secondary side of the damper by means of a

  support element which, in the event of relative rotation between the side

  primary tee and the secondary side can move in the peripheral direction along a sliding surface of the torsional oscillation damper, characterized in

  that the support element is lifted at least by zone with respect to

  port on the sliding surface when it cooperates with the

  support area on one side on the primary side and on the secondary side

  daire. According to the invention, the respective support element which cooperates with the support zone by the primary side or the secondary side, is raised at least by zone with respect to

the sliding surface.

  This lifting, at least by zone, during cooperation with the support zone, makes it possible to pass easily

  from a friction state with attachment to a friction state-

with sliding.

  We can for example provide that the or each

  support zone, on the primary side or on the secondary side,

  feels attacking an outer radial area at a bearing surface area of the respective bearing member with

an uplift segment.

  The lifting segment can be made in the form of a wedge, the angle of which is, at least per zone, less than the angle of inclination of the sliding surface, as

  opening angle between the radially outer zone

  upper area of support surface on the element

  support and sliding surface.

  The present invention will be described below from

  in more detail using exemplary embodiments

  shown schematically in the following figures: * Figure 1 is a partial longitudinal section of a torsional oscillation damper produced in the form of a flywheel with two masses, * Figure 2 is a partial axial section of the torsional oscillation damper of Figure 1, * Figure 3 is a sectional view of another support element according to the invention, * Figure 4 is another embodiment of an element d 'Support according to the invention, Figure 5 is a partial side view in principle of another torsional oscillation damper according to the invention. Figure 1 shows a torsional oscillation damper according to the invention in the form of a two-mass flywheel 10. The two-mass flywheel

  includes a primary side 12 which can be fixed by more

  several bolts 14 on a flange 16 belonging to a mo-

  tor generally bearing the reference 18, for example a crankshaft. The secondary side 20 can rotate about an axis of rotation A relative to the primary side 12 against the action of a damping device 22. For this there are several devices with different axial or radial bearings

24, 26.

  The primary side 12 comprises a first disc-shaped element 28 fixed to the shaft 18 as shown in Figure 1 and whose free end radially outside

  is joined together for example by welding to a se-

  cond disc element 32. The gap 34 formed between the two disc elements 28, 32 receives a central disc element or hub disc 36 belonging to the secondary side 20. A mass piece 38, or mass serving as a flywheel , is connected to this hub disc 36 by riveting or other means securing it in rotation; this part 38 in turn carries all of the pressure plates 40 of

the friction clutch.

  Both the primary side 12, i.e. the disc elements 28, 32 thereof, and the secondary side, i.e. the hub disc 36, have action zones alternating against which the springs 42 of the damping installation 22 can bear in the peripheral direction. These alternating action zones can be provided, for example in the case of disc elements 28, 32, on the axial projections of these elements; in the case for example of hub discs 36, these zones can be arm segments 44 which appear in particular at the

figure 2.

  According to FIG. 1, on the first element of dis-

  that 28, on the primary side 12, we have, in the peripheral direction

  risk, several deformations 46 in the form of pots which

  each time follow and form a bearing for a flat wheel

  shut up 48. Each planetary wheel is rotatably mounted on this

  bearing 46 in the form of a pot around an axis of rotation A1 es-

  substantially parallel to the axis of rotation A. The wheels

  48 have a peripheral zone with a

  toothed configuration 50 constituting a grip zone.

  A hollow wheel 52 is provided on the hub disc 36. This wheel has opposite teeth so that in the event of relative rotation between the primary side 12 and the side

  secondary 20, the planetary wheels 48 are rotated

  tion. This hollow wheel 52 can be produced as a separate part or as a separate assembly installed on the hub disc 36, for example by welding; this part can also be produced directly on the hub disc 36

by shaping and stamping.

  FIG. 2 shows that the damping device 22 of the exemplary embodiment shown comprises two sets of springs 60 formed each of five springs or groups

  of springs which follow one another 42 (these springs are nested).

  The springs or groups of springs 42 of each set of springs which are at the end zones in the peripheral direction, are supported at one of

  their end zones by means of clogs with res-

  spells 74 against the support or stress areas on the primary side 12, for example provided on the disc elements

  28, 32 or on the respective support or stress areas

  secondary side ves 20; in the embodiment example

  shown, it is a support arm or support 44

  hub disc 36. Between the different res-

  spells or groups of springs 42, there are pads 76 by the-

  which different springs or groups of springs 42

  can lean on each other. Both the sa-

  spring bots 74, that the pads 76 are movable in the

  peripheral direction along the peripheral surface in-

  78 of the cylindrical segment 30 of the disc-shaped element 28. To facilitate this movement and at the same time introduce a damping function, the chamber or

  space 34 contains a viscous lubricant, for example

  ple grease or the like.

  One difficulty, in particular at high rotational speeds, is that the spring shoes 74 and / or the shoes 76, which form the respective support elements, are pressed radially outward so strongly against the surface inner device 78 that the

  friction by catching this surface 78 increases enormously

  mement. Thus, for example during the return to neutral position, in which the torsional oscillation damper transmits practically no torque, the central support element 74 or / and 76 does not return to a corresponding position

  but remains retained just before this position. The same remark

  that applies to the travel with respect to the neutral position

  be; it is then necessary to overcome first of all an additional friction couple. This deteriorates the spring characteristic or damping characteristic of

  the torsional oscillation damper. The present invention

  tion concerns various means which allow, in the event of

  relatively high rotational braids and thus relatively intense centrifugal force, to avoid excessive increase in friction of the various support elements 74, 76 with respect to the smooth surface of the primary side 12 formed by

the inner surface 78.

  A first solution consists in using an optimal grease for friction, for example that known under the trade name "SYNTHESO GLK 1 PF" from the company Kl ber Lubrication Minchen KG. The use of such a lubricating agent significantly ensures that in the event of high stress by centrifugal forces,

  increased friction does not lead to deterioration

  considerable shock absorber behavior

  of oscillations of the torsional oscillation damper.

  An embodiment of a shoe 76 according to the invention is shown in FIG. 3. The body segment 80 is produced so that in its central zone, that is to say substantially in the zone which follows radially the projection bearing 86, it has a sliding surface segment

  92 coming to bear against the sliding surface 78. Par-

  both of this sliding surface segment 92, the body 80 is made so that the entire upper surface area 82 has an increasing distance D relative to the surface

  slip 78. When this shoe 76 moves in the di-

  peripheral rection, it acts by funnel effect to pass more lubricant into the area of the sliding surface segment 92; this allows pad 76 to move over the lubricant or a cushion of

  lubrication. It is clear that it is also possible to pre-

  see, in the upper surface area 82, cavities or

  additional grooves which, in addition to reducing the seg-

  surface of the sliding shoe 76 applied against the over-

  sliding face 78, reinforce the agent cushion

  lubricant. Note in Figure 3 a symmetrical realization

  slip of the sliding shoe 76; this means that starting from the middle peripheral zone defined by the support projection 86 and the sliding surface segment 92, the shoe 76

  extends, as in the embodiments presented above

  above, with its zones 98, 100 serving as radial support for the springs, practically identical in the two peripheral directions. A substantially identical movement characteristic is produced in the two directions of movement. FIG. 4 shows a support element 74 in the form of a spring shoe which also moves with a body segment 80 along the sliding surface 78 and whose

  support projection 86 participates in an enveloping support of the

  spells and by a rounded outline it leans against a con-

  complementary turn on the primary side 12 and / or on the secondary side 20. It can be seen that in this case also the surface area 82 facing the sliding surface 78 has

  a hollow zone 88 in which one can have an accumulation

  lubrication agent. We recognize in this embodiment

  sation that this cavity-shaped zone 88 is opened by a channel device formed by at least one through orifice 94 going towards the side 84 of the spring shoe 74 not turned

  towards the sliding surface 78. This allows the agent to

  brifiant to arrive in the area between the sliding surface-

  ment 78 and the upper surface area 82, by the peripheral movement of the spring shoe 4 but also radially

  outward under the effect of centrifugal force, through

  towards the channel device 94 to arrive in the zone in

cavity shape 88.

  It is clear that the means described above for reducing friction, that is to say essentially for forming a cushion of lubricating agent between a support element and the associated sliding surface, can be combined with one another. Thus, in all the embodiments described above of a support element, it is advantageous to use a lubricating agent or a grease with an optimal characteristic.

  for friction. In addition, in all of these embodiments,

  tion, it may be advantageous to supply the sur-

  upper face 82, in particular the area of the cavity 88 by a channel device, open towards the side of the support element not turned towards the sliding surface 78 to ensure

supply of lubricant.

  Figure 5 shows another embodiment of a torsional oscillation damper. The components corresponding to those already described above, by their function or their structure, bear the same references with

the addition of the suffix "a".

  The damping device 22a comprises several

  sets of springs 60a which follow one another in the peri- direction

  spherical; it may for example be several successive springs or also nested springs. Each set of springs 60a is supported by its peripheral end zones, each time by a respective support element 74a against the support zones on the primary side 12a or the support zones on the secondary side 20a. It is recognized that, for example, the support zones on the primary side 12a can be produced by attached disc elements, as already mentioned and described in connection with FIG. 1 or also by support projections.

  200a formed by relief moldings while the zo-

  nes of support on the secondary side 20a must be formed by

  the respective arm segments 44a. We see that, in the di-

  peripheral rection, the support zones, i.e. the

  arm segments 44a on the secondary side 20a, have an extension

  slightly weaker than the support projections 200a on the main side

  mayor 12a. As a result, the secondary side 20a can be rotated until it is put into action, that is to say until

  that it arrives on the respective support elements 74a in turn-

  from a small angle relative to the primary side 12a. This

  is for example only when switching to traction mode, for the-

  which arm segment 44a shown in FIG. 5 is stressed

  cite for example the support element 74a located on the right, towards

  a thrust mode for which this arm segment 44a requests

  then cite the support element 74a located on the left, that this year

  gle then exhausts the minimum authorized angle of rotation and that the arm segment 44a then acts on the support element 74a which cooperates with this arm segment 44a during the state of

  next operation to transmit the torque.

  FIG. 5 shows that the support elements 74a have a surface area 202a, of support, curve, for cooperating with the support areas of the primary side 12a or of the

  secondary side 20a; the curvature of this zone 202a corresponds to

  essentially lays on that of the support surface 204a curve of the support projections 200a. The arm segments 44a also have a corresponding bearing surface 206a which however has a different curvature. It is recognized that in its outer radial area this bearing surface 206a corresponds to a smaller angle relative to the sliding surface 78a or a tangent applied thereto; it is a corner angle less than the opening angle formed in this radially outer zone between the bearing surface 204a and the sliding surface 78a or relative to

  a tangent applied to this surface. The effect that

  sulte, is that the movement of approach of the arm segment 44a towards one of the support elements 74a pushes the external radial zone 208a of this arm segment 44a which forms a lifting segment in this zone, in the manner of a corner against the support surface area 204a and sinks

  thanks to this small angle between the support element 74a and the sur-

  sliding face 78a. It is important here that the attack takes place in the outer radial zone, that is to say even more outside of the zone in which the damping springs are pressed against the support element 74a; it is only if, by this attack, the support element 74a is raised by zone with respect to the support surface 78a, that the support surface area 206a comes into surface engagement against the element d 'support 74a. In this situation, the support element 74a is essentially only still in contact

  with a peripheral end zone 110a remote from the segment

  corresponding arm 44a against the sliding surface

  78a. This results in a significant reduction of

  the friction effect between the support element 44a and the track

  slip jectory 78a so that for example at the step-

  wise from the traction mode to the pushing mode, by the attack of the arm segment 44a against one of the support elements 74a, the sets of springs 60a act by elasticity and do not create

of shaking.

R E V E N DI C A T I ON S

  1) Torsional oscillation damper (10) comprising a

  support element for supporting a deformed damping element

  elastically against the primary side (12) and / or the secondary side (20) of the shock absorber (10) or against another elastically deformable shock absorber element (42), the support element having a surface area upper (82) placed on the damper (10) so as to be turned towards a sliding surface (78), zone (82) by which the support element moves along this sliding surface (78) , characterized in that * the support element (76) comprises, in its upper surface area (82), a sliding surface segment (92) for pressing against the sliding surface (78), and * this support element (76) is configured at its

  upper surface area (82) so that when the seg-

  ment (92) is applied against the sliding surface

  (78), the distance (D) between the sliding surface-

  ment (78) and the upper surface area (82) increases to

  from the segment (92) in at least one direction of de-

  placement of the support element (76).

  2) Shock absorber according to claim 1, characterized in that the distance (D) between the upper surface area (82) and

  the sliding surface (78) increases in both directions

  displacement from the segment (92).

  3) Shock absorber according to claim 1, characterized in that the segment (92) is provided in the direction of movement, essentially in a central region of the support element (76). 4) Shock absorber according to claim 1, in particular for a

  dual mass flywheel or a clutch disc,

  taking a primary side (12a) and a secondary side (20a) which can rotate about an axis of rotation relative to the

  primary side (12a) against the action of a damped device

  sor (22a), comprising at least one unit with damped elements

  sisters (60a) which can bear in their peripheral end zone against a respective support zone (200a, 44a) on the primary side (12a) and on the secondary side (20a), by means of an element support (74a), which, in the event of

  relative rotation between the primary side (12a) and the dry side

  condaire (20a), can move in the peripheral direction

  as along a sliding surface (78a) of the torsional oscillation damper (10a), characterized in that it comprises

  a support element (74a), raised at least by zone relative to

  port on the sliding surface (78a), when it cooperates with the support zone (206a) on one (20a) of the primary sides (12a)

and secondary (20a).

   ) Shock absorber according to claim 4, characterized in that

  a support zone of one (20a) of the primary sides (12a) and se-

  condaire (20a) cooperates in an outer radial zone to

  a support surface area (204a) of the support element

  pectif (74a) with an uplift segment (208a).

  6) Torsional oscillation damper according to the claim

  tion 5, characterized in that the lifting segment (208a) is wedge-shaped,

  the angle presents at least per zone, a lower inclination

  ble relative to the sliding surface (78a) that the opening angle formed between an outer radial area of the bearing surface area (204a) of the respective bearing member

  (74a) and the sliding surface (78a).