FR2784154A1 - TORSIONAL OSCILLATOR WITH AT LEAST ONE MEANS FOR COVERING A JOINT - Google Patents

Abstract

Torsional oscillation damper comprising a damping element on the inlet side and a damping element on the outlet side, capable of rotating relative to that on the inlet side, these two damping elements being connected to each other. the other by means of energy accumulators, at least part of these being in a chamber at least partially filled with a viscous liquid, the chamber being protected by at least one seal against the loss of viscous liquid, and at least one cavity is provided in at least one damper element which is adjacent to the corresponding seal and performs cooling or mounting functions. The seal (33, 66) has on the face opposite the chamber (17) , a covering (47, 70) surrounding the seal (33, 66), this covering being provided on a damping element in the extension zone of the respective cavity (46, 69) and arrives in the form of a labyrinth seal up to the gap level with cha than any other damping element.

Description

The present invention relates to a torsional oscillation damper

  comprising a damping element on the entry side and a damping element on the outlet side, capable of rotating relative to that on the entry side, these two damping elements being connected to each other by the energy accumulators, at least part of these being in a chamber at least partially filled with a viscous liquid, the chamber

  being protected by at least one seal against loss of li-

  which is viscous, and at least one cavity is provided in at least one damping element which is adjacent to the cor-

  corresponding and provides cooling or mounting functions. According to document DE 196 20 698 A1, there is known a torsional oscillation damper comprising a damping element fixed on the side of the drive by means

  drive for example the crankshaft of a

  internal bust and having at its output a damping element which can rotate relative to the input damping element; the two damping elements are connected by

  energy accumulators. The energy accumulators are lo-

  housed in a chamber at least partially filled with a viscous liquid and having seals to avoid

  loss of viscous liquid. A first joint is located axial-

  between a damper hub disc on the outlet side and a radially penetrating sealing plate which is attached to the damper on the inlet side. A second seal is provided radially more inside; it is constituted by an axial bearing maintained in abutment against the hub disc of the damping element on the outlet side by a spacer member fixed on the inlet damper member, this spacer member being provided between the two damping elements. The two seals have in common that each delimits a cavity and at the same time the

  cavity associated with the outer radial seal passes as an inter-

  valle between the sealing plate of the input damping element and a mass of inertia of damping elements

  outlet, directed radially outwards.

  This cavity must make it possible to ensure the relative mobility of the damping elements as well as nutation movements and in such torsional oscillation dampers, this cavity is also often used to conduct cooling air arriving radially at

  the inside to make it escape radially outwards

  laughing thus constituting an air passage. Such an air passage with corresponding air guides is for example

  described in document DE 41 27 438 CI.

  Returning to document DE 196 20 698 A1, the cavity associated with the internal radial seal is used for the passage of the fixing means for connecting the input damping element

  to the engine crankshaft. With this cavity is associated an ori-

  mounting part in the hub disc.

  Such a torsional oscillation damper is

  usually housed inside a gearbox housing

  its, but it is not excluded that dust and pro-

  jections of water enter it and arrive through the cavities described above after passing the seals into the chamber filled with viscous liquid. This can damage the parts housed in this room, for example by dust from parts moving relative to each other, the

  dust with viscous liquid having an abrasive effect.

  The present invention aims to develop a torsional oscillation damper preventing the penetration of dust and water splashes in the filled chamber

viscous liquid.

  To this end, the invention relates to a shock absorber

  torsional oscillations of the type defined above, characteristic

  laughed in that the seal has on the face opposite to the chamber, a covering surrounding the seal, this covering being provided on a damping element in the zone of extension of the respective cavity and arrives in the form of a seal labyrinth up to the level of the interval with

each other damping element.

  To complete each joint on its side not turned towards the chamber with a covering which surrounds the joint, in the extension zone of the respective cavity and in the form of a labyrinth joint, by cutting the width of

  the interval to reach the other damped element

  protection, the seals are protected from the cavity open to the outside. Thus, dust particles and water projections sucked in by the rotation of the torsional oscillation damper, at least in one

  cavity, go over the joint cover and do not

  do not enter through the seal into the chamber filled with li-

  that viscous. Instead, the respective recovery

  is advantageously made so that the air charged with particular

  dust and splash water again

  thrown out of the cavity to avoid any accumulation of dirt

inside the cavity.

  An advantageous solution for removing charged air,

  is to provide the cover at its side facing the ca-

  a flow guide means for air; this guide means is advantageously provided with a guide surface leading radially outward because, due to the rotation, a pressure difference will be established from the inside towards the outside in the radial direction, and this pressure difference promotes the suction of air deflected by the guide surface. This guidance can

also be axial.

  The invention relates to advantageous embodiments of such a covering and in the case of a joint, the covering is provided in the zone radially outside by being advantageously fixed on one of the two

  damping elements; this recovery consists of a plate

  that of covering coming with at least its surface of guu-

  air passage in the extension zone leading radially to the outside. By the guide or air guide means, the air which penetrates and contains dirt is guided along the cover plate and thus over the corresponding seal in the air guide in which under the effect of the pressure difference which is established there during the rotation of the torsional oscillation damper, is

  again discharged radially outwards. Cover it

  ment of the cavity receiving the means for fixing the shock absorbers

  on the contrary, torsional oscillation weavers are preferably produced on an already existing part such as for example a spacer and this in the form of a lip covering the joint; this lip functions as part of the guide surface of the cover serving to guide the flow. The air drawn into the cavity is again

  calf leads outward along this lip of re-

  covering and a radial extension of the guide surface in the direction of exit, promotes the evacuation of the charged air. In the overlaps of the respective seal, due to the embodiment in the form of a labyrinth seal, any additional friction in the torsional oscillation damper is avoided, which would reduce the decoupling characteristics and increase the wear. Thanks to the function of S15 additional protection of the chamber filled with liquid

  viscous, there will therefore be no negative counterpart.

  The present invention will be described below in more detail with the aid of an exemplary embodiment

  shown schematically in the accompanying drawings in the-

  which: - Figure 1 is a longitudinal section of a half axial view of a torsional oscillation damper with an overlap at a joint, - Figure 2 is a detail view on a scale

  enlarged area of overlaps.

  Figure 1 shows a drive means 1 in the form of the free end of a crankshaft 3 of an internal combustion engine. On a shaft flange 5, a radial flange 6 facing outwards and forming part of a torsional oscillation damper has been fixed by a fixing means 7; this radial flange 6 externally joins a peripheral wall 9. This wall carries a toothed crown

  11 to mesh with the pinion of a starter not shown

  tee, as well as a complementary mass 13. The peripheral wall

  that 9 is furthermore integrally connected to a sealing plate 15 directed inwards. This plate forms with the radial flange 6 the limit of a chamber 17 at least partially filled with a viscous liquid. Chamber 17 receives a damping installation 19 comprising

  elastic elements 21 extending in the peripheral direction

  risk; the elastic elements are supported radially outwards on sliding elements 23 which are themselves guided in the inner radial face of the peripheral wall 9.

  The control of the elastic elements 21 in the direction of

  ripherique is done using control means 25 located on the drive side; these means are provided on the faces of the radial flange 6 and of the sealing plate 15

  turned each time towards chamber 17. The elastic elements

  that 21 are supported by their opposite ends in the di-

  peripheral rection against an output control means 27

  formed by radially projecting fingers and appearing

attached to a hub disc 29.

  As shown on an enlarged scale in FIG. 2, the hub disc 29 serves in its median radial part in support of an axial spring 31, resting moreover on the axial face of the sealing plate 15. This axial spring 31 constitutes the first seal 33 for the chamber 17. Radially inside this seal 33, the disc 29 is fixed by rivets 35 to a mass of inertia 37. This mass delimits with

  the sealing plate 15, an air passage 39 directed radially

  outward. This air passage joins in the internal radial zone of the mass 37, air passages 45 distributed at the periphery, and which extend essentially in the radial direction. In the peripheral direction, between each two air passages 45, the mass of inertia 37 has an axial projection 41; a fixing flange 44 of a cover plate 43 is fixed between the face of the

  axial projections facing the disc 29 and this disc 29.

  Radially outside this fixing point, the cover plate 43 has a guide surface 48 which on the one hand covers the seal 33 radially and on the other hand serves, thanks to its guide surface 48, to guide means d air 49 for the air arriving through the supply channel

  air 45; the air is thus guided along the fixing flange

  tion 44 towards the guide surface 48 to be deflected by the latter in the air passage 39 and then pass over the

attached 33.

  As soon as the air is in the air passage 39, radially outside the cover plate 43, the rotation of the torsional oscillation damper, under the effect of the radial pressure differences applied to the air passage 39, the air is sucked in radially towards

  outside. Dirt particles and possible water-

  ment contained in the air, are thus evacuated so that the cover plate 43 prevents this dirt from entering the extension zone of the seal 33 and can penetrate into the chamber 17. As the cover plate 43 thus guides the air next to seal 33 and that plate 43 can cover this

  joint 33, the plate 43 will be referred to below as a means of covering

  47. The air supply 45 with the air passage 39 functions as a cavity 46 serving to cool the

the torsion damper.

  This cooling is particularly important because, in such torsional oscillation dampers, the side of the inertial mass 37 opposite the hub disc 29 usually receives friction linings from a clutch disc which is part as is known. of the housing

  clutch of a friction clutch. The friction of the gar-

  corresponding niture of the clutch disc against the friction surface 42 (Figure 1) of the inertial mass 37 gives off heat which must not arrive in the chamber 17, because it would disturb the properties of the viscous liquid. The hub disc 29 constitutes in the radial extension zone of the covering 47, on its turned face

  towards chamber 17, the hollow wheel 52 of a flat transmission

  currency 54; the latter is meshed with at least one planetary wheel 56. This wheel 56 is mounted on a bearing 58 of the radial flange 6, so that the latter operates

as planetary support 60.

  Radially inside the cover 47, a spacer 62 is fixed to the radial flange 6 by a

  fastening means 7. This is applied on one side of a pa-

  bind axial 64 and its other side comes against the disc of

  hub 29 (figure 2). This axial bearing 64 functions as

  cond seal 66 for the chamber 17. A mounting hole 68 is provided for this seal 66 in the hub disc 29 for the passage of the fixing means 7. The mounting hole 68 continues with a cavity 69 functioning as housing and passage for the fixing means 7. In this cavity 69, when the torsional damping oscillator rotates, air can also be sucked around its central axis 94, air which is charged with dirt particles and water. At this point, we also want to avoid that the uncleaned air can arrive through the seal 66 in the chamber 17. For this reason, the spacer 62 is provided with a lip

  cover 76 passing axially over the joint 66.

  IS This cover lip 76 is used with the

  axial tie of the spacer 62 directed in the direction

  tion of the radial flange 6, as a guide surface 72 thus associated for air with the spacer 62 to ensure the complementary function of flow guide means

  74. The guide surface 72 is enlarged radially

  advantageously in the direction of the mounting hole 68 to develop a pressure difference favoring the

  air transfer along the guide surface 72 in the direction

  the mounting hole 68. The mounting hole 68 comprises

  carries a guide surface 86 so that the air arriving from the

  guide surface 72 of the spacer 62 can come out

  firing by the guide surface 86 of the hub disc 29.

  The free end of the cover lip 76 is thus driven axially in the direction of the hub disc 29 enough to penetrate in the axial direction in a

cavity 78 of this disc.

  As the spacer 62 thus conducts air over the associated seal 66, this spacer 62

  functions as covering means 70 for the seal 66.

  As for the covering means 47 described above, the

  covering means 70 is not applied each time

  watertight only against the adjoining part making a movement

  relative relative so that the two means of recovery

  47, 70 function each time as a labyrinth seal.

  Radially inside the mounting holes 68, the radial flange 6 has a primary hub 80 which moves away from the crankshaft 3 and enters a radial bearing 82 in the form of a smooth bearing. The radial bearing 82 surrounds it

  even a secondary hub 84 formed at the inner radial end

  hub disc 29 and thus extending in direction

crankshaft 3.

  Finally, it should be noted that the flange

  6 with the peripheral wall 9 and the sealing plate 15 as well as the planetary wheel 56 and

  the damping installation 9 form a damping element

  sor 90 on the drive side for the torsional oscillation damper while the hub 29 and the inertia mass 37 constitute a part of the damping element

  output 92. The hub disc 29 functions here as a pre-

  part 96 of the damping element 92 on the side of the

  exit of the movement while the mass of inertia 37 functions

as second part 98.

NOMENCLATURE

  1 Drive 3 Crankshaft 5 Shaft flange 6 Radial flange 7 Fastening means 9 Peripheral wall 11 Toothed crown 13 Additional mass Sealing plate 17 Chamber 19 Damping system 21 Elastic elements 23 Sliding elements Input control means 27 Medium output control 29 Hub disc 31 Axial spring 33 First seal Rivets 37 Inertial mass 39 Air passage 41 Axial projections 42 Friction surface 43 Cover plate 44 Fixing flange Air channel 46 Cavity 47 Cover 48 Surface guide 49 air guide 52 Hollow wheel 54 Planetary transmission 56 Planetary wheel 58 Bearing Planetary support 62 Spacer 64 Axial bearing 66 Second seal 68 Mounting hole 69 Cavity 70 Cover 72 Guiding surface 74 Circulation guide 76 Lip cover 78 Cavity 80 Primary hub 82 Radial bearing 84 Secondary hub 86 Guide surface Damping element on the inlet side 92 Element damping on the output side 94 Geometric axis 1!

Claims (9)

R E V E N D I C A T ION S   1) Torsional oscillation damper comprising an element   damper on the entry side and a damping element   sor on the outlet side, capable of rotating relative to that on the inlet side, these two damping elements being connected to each other by means of energy accumulators, at least part of these being in a chamber at least partially filled with a viscous liquid, the chamber being protected by at least one seal against the loss of viscous liquid, and at least one cavity is provided in at least one damping element which is adjacent to the corresponding seal and performs the cooling or mounting functions, characterized in that the seal (33, 66) comprises on the face opposite to the chamber (17), a covering (47, 70) surrounding the seal (33, 66 ), this covering being provided on a damping element (90, 92) in the extension zone of the respective cavity   (46, 69) and arrives in the form of a labyrinth seal up to   that at the interval with each other damping element weaver (90, 92).   2) Torsional oscillation damper according to the claim   tion 1, characterized in that the covering (47, 70) has on its side facing the   cavity (46, 69), a flow guide (49, 74) for the cavity   tee (46, 69), this flow guide (49, 74) deflecting the air from the seal (33, 66) respectively.   3) Torsional oscillation damper according to the claim   tion 2, characterized in that the flow guide (49, 74) has at least one guide surface (48, 72) which conducts air radially outwards.   4) Torsional oscillation damper according to the claim   tion 3, comprising a spacer member provided axially between the two damping elements, this member being fixed to one of the damping elements and pressing against the other damping element by an axial bearing serving to   the tightness of the chamber, and surrounding at least partial-   ment a cavity with a mounting hole for the fixing means, characterized in that the spacer (62) functions as a cover (70) for the axial bearing (64) and on its side opposite to the axial bearing, it has a guide surface (72) which widens radially outwards towards the orifice of   mounting (68) of the fixing means (7).    ) Torsion oscillation damper according to claim 4, characterized in that the spacer (62) comprises a covering lip (76) which extends axially beyond the axial bearing (64), this lip   penetrating into a cavity (78) of the shock absorbing element sin (92).   6) Torsional oscillation damper as claimed   cations 3 and 5, characterized in that the cover lip (76) acts as a guide surface   (72) on its side facing the cavity (69).   7) Torsional oscillation damper according to the claim   tion 3, comprising a sealing plate provided on one   of the two damping elements, this plate arriving radia-   internally in an annular opening between two adjacent parts of the other damping element and   cooperating on an axial side with one of the chamber seals   bre while the other axial side is turned towards an air passage used for cooling, characterized in that axially between the two parts (96, 98) of the other damping element (92), a covering has been fixed ( 47) in the form of a cover plate (43) whose guide surface (48) penetrates axially between the sealing plate (15) and the part (37) of the corresponding damping element (92), see sin of the air passage (39).   8) Torsional oscillation damper as claimed   tion 7, characterized in that the cover plate (43) enters the area of extension of an air guide (45) towards the air passage (39).   9) Torsional oscillation damper according to the claim tion 8, characterized in that   the air guide (45) extends essentially radially.   10) Torsional oscillation damper as claimed cation 8, characterized in that   the air guide (45) extends essentially axially.