FR2765933A1 - TORSION SHOCK ABSORBER - Google Patents

Abstract

The torsional stress of the radially outermost torsion spring (22) is smaller than the torsional stress of at least one of the radially inner torsion springs (24) housed in that torsion spring (22) ) outermost.

Description

Description

  The invention relates to an oscillation damper.

  torsional positions comprising a transmission element located on the side of the drive and a transmission element located on the side of the power take-off which can for this be articulated

  ler on the same axis, and which is connected to the trans-

  mission located on the drive side using a system

  damping system with energy accumulators present

  both in the form of torsion springs, the various torsion springs being arranged radially one inside the other and at least one control element being associated with

  each transmission element for at least one of the accumu-

energy readers.

  Document DE-41 28 868-A1 discloses a torsional oscillation damper with an element of

  transmission, located on the drive side and with an ele-

  transmission located on the side of the power take-off which can therefore be articulated on the same axis, the latter

  element being connected to the transmission element, which is so-

  killed on the drive side with a device

  damping system with energy accumulators, which pre-

  feel in the form of torsion springs. The torsion springs can be stressed by control elements which are provided on each of the transmission elements. Figure 1 shows for example a control element which extends radially outwards from the disc of the hub, control element which acts on both sides by means of spring pots on a torsion spring respectively, which of its side is connected in turn by means of a sliding pad to other torsion springs. The sliding elements, that is to say the spring pots as well as the sliding pad, have projections which extend respectively in the direction of the neighboring element in the direction

  peripheral, which compared to the torsion springs represented

  felt grow radially outwards towards the free end respectively and are operational both as radial supports for torsion springs and

  as stops also serving to limit the depression of the

  comes out. To obtain a good sliding possibility, the spring pots and the sliding pads can be provided at least on their outer radial side with a Teflon additive. As a basic material, one can think of a plastic material reinforced with glass fibers or carbon fibers. Energy accumulators can also be ordered

  by these spring pots and these sliding pads, accumulated

  Readers who, according to FIG. 2 of the request for public inspection, have two radially located springs

one in the other.

  In the case of torsional oscillation dampers with a damping device of this type, we

  adjusts the radially outermost torsion spring

  laughing, which must transmit the highest torques, ha-

  usually in such a way that the torsional stress arrives by its turns as close as possible to a predetermined load limit. A second torsion spring, which is located radially inside this torsion spring, is also adjusted in such a way that it approaches this limit value, however the torque transmissible by

  this torsion spring is weaker than in the case of the res-

  outside twist due to the smaller diameter of its turns

  As soon as the torsion spring deforms in

  producing a relative movement between the trans-

  mission, it deviates from its position shown in FIG. 1 with respect to the spring pot and the sliding shoe and

  it comes to bear on this radial support by its zones of extension

  which are located inside the corresponding radial support

  laying, concerning respectively the last turns. The area of the turns, which remains between respectively two radial supports, of the torsion spring undergoes on the other hand due to the

  centrifugal force a curvature radially outward.

  During the increasing compression of the torsion spring the turn which is close to the free end of the corresponding radial support in the direction of compression comes to bear on this radial support so that the force which has been

  introduced and which causes the torsion spring to deform

  Zion cannot be introduced further by this turn prevented by the radial support from performing another movement

  on the turns which remain radially inside the ap-

  then radial. In this way the deformation path of the res-

  torsion spell is shortened around the part of the last turns mentioned. The consequence of this is that

  the turns beyond this turn which is hung solid-

  radial support may approach each other

  much more strongly than is possible with the dimension of the radial supports in the peripheral direction. In this way these turns are exposed to a load which goes beyond the predetermined limit value and, in particular when the turns form a block with each other, leads to a rupture of the torsion spring. This problem is further aggravated when we have, according to FIG. 2, radially

  inside the torsion spring another torsion spring

  sion, which rests radially on the torsion spring which

  is outermost under the effect of the central force

  trifuge and which increases in this way the total mass of the

  fate subjected to centrifugal force.

  The same problems arise in principle for

  the torsion spring which is located radially inside

  laughing, while its turns are pressed against the circumference-

  inner rence of the radially outer torsion spring with high surface pressure. Because of the weight more

  weak radially inner torsion spring

  However, this is due to the centrifugal force.

  In addition, the two torsion springs are most often arranged in a lubrication chamber, which is filled at least in part with a viscous agent, so that a friction of relatively small value is established during

  of the steel on steel contact of the torsion springs. The situation

  tion is different in the case of external torsion springs

  laughers, when the spring pot or the sliding pad, with which it is in friction contact, are made in

  a plastic material, which contains for reasons of

  resistance of glass fibers or carbon fibers, which reach the surface by abrasion. The consequence is one

  increased braking or blocking effect.

  From document DE-40 18 321-A1 we have represented

  felt in Figure 2 a damper of oscillation of tor-

  sion, which has, also between two transmission elements, a damping system with accumulators

  of energy in the form of torsion springs.

  Here, too, two torsion springs are arranged radially one inside the other, providing for the radially external torsion spring a guide track, on which it bears radially outside. When we design two

  torsion springs very close to a predetermined limit value

  born, we can in fact transmit the highest torques, however, there remains however the problem of the turns which due to the centrifugal force are driven radially towards

  the outside and in particular the turns of the torch spring

  radially outer sion which in this case come in liai-

  its by friction engagement with the guide track. What we cannot see in Figure 2 is the fact that

  the different turns of such a torsion spring do not present

  try not absolutely the same diameter, but oscillate inside

  within specified diameter tolerances. Because of this, coils with a relatively large diameter can

  remain attached to the radially outer guide track

  lower, so that the turns, which are located on the opposite side of the turn which remains hooked located opposite the introduced torque, are no longer used to collect this couple. Instead it occurs for the turns which

  are located before the turn firmly attached a deformation

  stronger than that which was envisaged by construction

  tion, so that it is superimposed on the torsional stress in the windings too high a bending stress. The consequence of this is damage or even

a rupture of the turns.

  The object of the invention is to constitute a damping system on a torsional oscillation damper, so that damage or rupture of the energy accumulators, in particular the springs, is avoided.

twist of these.

  This problem is solved by the fact that the con-

  torsional drag of the radially outermost torsion spring is smaller than the torsional stress

  at least one of the radially integrated torsion springs

  laughers housed in this outermost torsion spring

  laughing. As already mentioned at the beginning, we adjust all the torsion springs which are inside one another of an energy accumulator in such a way that their torsional stress approaches a determined limit value . But according to the invention, the stress of

  torsion of the radially outermost torsion spring

  while the torsional stress of the torsion spring

  radially in it remains the same or is even slightly increased to compensate at least in part for the loss that occurs on the torque that can be transmitted, and which is caused by the

  reduction of the torsional stress on the torsion spring

  outermost area. In this way the torsion spring which is radially outermost can because of the problem that was described at the beginning, according to

  which a turn hooks to a resistor guide element

  sort, such as for example a sliding element or a

  guide track, being compressed makes it ever stronger-

  ment that it is not intended by construction and in this way the bending stresses which manifest themselves in the turns can be higher than is desirable. However, this no longer leads to the reduction of the stress

  of torsion in the turns to a rupture of the torsion spring

  sion, because its starting load compared to a torsion spring with a higher torsional stress is already reduced. In the case of the torsion spring radially more inside there is no reason on the other hand to expect a

  failure despite the torsional stress which also remains high

  or even higher, because this spring due to its lower dead weight and its ability to bear on the radially outermost torsion spring is exposed to a lower bending stress than the spring

  of radially outermost torsion.

  According to other characteristics of the invention: - the distance between respectively two windings of the internal torsion spring is, at least in the unloaded state, greater than that between respectively two turns of the external torsion spring, - the torsional stress of the radially outermost torsion spring is reduced until even in the case of excessive bending stress in the turns

  the overall stress that can withstand without damage

  these are not exceeded, - the torsional torque / elastic force of the radially outermost torsion spring is less than or equal to the torsional torque / elastic force of at least one of the radially inner torsion springs, which

  is housed in this outermost torsion spring.

  The invention will be described below in more detail.

  tail from an exemplary embodiment, shown in the accompanying drawings, in which:

  - Figure 1 shows a partial view of a bone shock absorber

  torsion cillations with a damping system, on which torsion springs are maintained by means of spring pots and sliding pad; - figure 2 shows the same thing as figure 1, but with

  guiding the torsion springs in a guide track

  dage; - Figure 3 shows a fragment of two torsion springs, located radially one inside the other under the action of

  load and centrifugal force.

  In Figure 1 we have drawn a bone damper

  torsional cillations in the form of a two-mass flywheel, which has a first mass of inertia in

  as transmission element 1, located on the drive side

  and a mass of inertia, which can rotate around the same axis of rotation 13 with the preceding element, as a transmission element 3, located on the outlet side. There

  No need to go into more detail on the assembly.

  of a torsional oscillation damper of this type, since it can be drawn substantially from document DE-41 28 868-A1, mentioned at the start. At this stage we will only extend on the damping system 6 between the two

transmission elements 1, 3.

  To receive this damping system 6, an annular space 7 is formed in the transmission element 1, located on the side of the drive, into which a control element 9 provided on the outside of a hub disc penetrates. 5, associated with the transmission element 3, located on the outlet side. With this control element 9 there is, seen in the peripheral direction, on the two sides respectively a pot of springs 17 in support, one of which is shown in FIG. 1. This pot has a peripheral support 10 for one end a torsion spring 22 radially outside and a second torsion spring 24 disposed in the first. The radially outer torsion spring 22 is held on its last turns 25, facing the spring pot 17, by a radial support 19 of this spring pot 17, the free end 20, located on the side of the periphery, of this support radial 19

  to be oriented on a sliding pad 29, on the ap-

  then peripheral 10 from which the other ends are supported

  torsion springs 22 and 24 respectively and which is also

  Lely operational like the spring pot 17 as an element

  ment of slip 30. The last turns 25, 26 at this

  end of the torsion springs 22, 24 are also wrapped

  weighed by a radial support 31 of the sliding pad 29, this device

  then radial 31 being oriented towards the spring pot 17.

  Between the free end 33 of the radial support 31 and the end

  free tee 20 of the radial support 19, there remains, as long as the torsion springs 22, 24 are not extremely compressed, an intermediate space 34, which is also filled, like the remaining annular space 7, at least in part , of a viscous agent, and which consequently forms part of a grease chamber 11. An energy accumulator 27 is formed by the

  two torsion springs 22, 24. This is connected by the

  intermediate of the sliding shoe 29 to another energy accumulator 27, the sliding shoe 29 having, on its side turned towards another sliding shoe 29, a support

  radial 32. After a number, which can be determined by the

  alable, such energy accumulators 27 this damping device 6 is supported, in a manner that has not been shown, on another control element, which is provided

  on the transmission element 1, located on the side of the drive

  is lying. In this way, the introduced torsional oscillations are passed through by means of the damping device.

  6, from one of the transmission elements to the other respectively-

  is lying. In Figure 1 there is shown the torsion springs 22, 24 in a free state of charge without rotational movement of the torsional oscillation damper. Under load, the various turns 25, 26 according to FIG. 3 are found more closely brought together, while under the action of centrifugal force the torsion springs 22, 24 are bent at the same time radially outwards and in this case come to bear both in the area of the radial support 19 of the spring pot 17 and in the area also of the radial support 31 of the sliding pad 29 respectively on their radial inner sides 40, 41, while qu 'They sink into the intermediate space 34 and even into the radial area of the radial supports 19, 31. In the case where the torque in a counterclockwise direction according to Figure 1 is introduced by the element of command 9,

  o consequently the spring pot 17 moves in the direction

  tion of the neighboring sliding shoe 29, the turns which are in the intermediate space 34, which are close to the end 33 of the radial support 31, and which are provided in FIGS. 2 and 3 with the reference 28, come into abutment at the free end 33 of the radial abutment 31. In this way the situation arises in which the turns 25, 26, which are opposite the torque introduced with respect to the turn 28, do not undergo no other deformation, and in this way no longer provide part of the elastic path of the torsion springs 22, 24. Due to the elimination of this part of the elastic path the turns 25, 26 on the other side of the turn 28, therefore those which are turned towards the introduced torque, are compressed more strongly than is desired up to the turn 28, so that these undergo unintentionally high bending stresses and if necessary even block . In this case the

  two radial supports 19 and 31 of the spring pot 17 and of the pa-

  Tin 29 is not operational because it does not come

  do not yet come into contact with each other despite the too tight approximation of the turns 25, 26 of the torsion springs 22, 24. To solve this problem we reduce according to

  the invention the torsional stress in the torsion spring

  sion 22 radially outside until even in the case of a higher bending stress the overall stress in the turns 25, 26 does not exceed an admissible value

  overall. In this way, the torsion spring is protected.

  external dialing 22 against damage. However, the radially inner torsion spring 24 can be

  made with high torsional stress without change-

  ment, because the overall load of this torsion spring 24 is lower than that of the torsion spring 22 radially outside. In the case of the embodiment according to the

  Figure 2 the grease chamber 11 in the transmission element

  sion 1, which is located on the drive side, is surrounded by a sleeve 37 which acts as a guide track 35, sleeve on which the torsion spring bears radially

  22 radially outside of an energy accumulator 27.

  As the different turns 25 of the torsion spring 22 move with respect to their outer circumference within a determined tolerance range, a turn 28, having a relatively large outer circumference, may, due to the centrifugal force be easily attached to the guide track 35 under the effect of the torque and the simultaneous influence of the centrifugal force. Even in this case the elastic path on the side of the hook wound

  28, located opposite the introduction of the couple, is

  would be lost for the energy accumulator 27. We can all-

  times to avoid the consequences of a spring break on the opposite side of said turn 28, in accordance with the invention,

  by reducing the torsional stress in the torsion spring

  Radially outer sion 22. Even in the case of this reaction

  The internal torsion spring 24 can remain formed with an unchanged torsional stress. Due to the configuration of the two torsion springs 22, 24 with different torsional stresses, both in the case of the embodiment according to Figure 1 and in the case also in the case of the embodiment according to Figure 2, the distance respectively between two turns 25 of the radially outer torsion spring 22 is smaller

  that between two turns 26 of the torsion spring radially in-

24.

  References 1. Transmission element (drive side) 3. Transmission element (output side) 5. Hub disc 6. Damping system 7. Annular space 9. Control element 10. Peripheral support 11. Grease chamber 13. Rotation axis 17. Spring pot 19. Radial support 20. Free end 22, 24. Torsion spring, 26. Spiers 27. Energy accumulator 28. Spire 29. Sliding shoe 30. Sliding element 31, 32. Radial supports 33. Free end 34. Intermediate space 35. Guide track 37. Sleeve

, 41. radial inner sides.

Claims (4)

R E V E N D I C A T IONS   1) Torsional oscillation damper comprising an element   transmission side located on the drive side and a   transmission element located on the side of the power take-off   which can therefore be articulated on the same axis, and which   is connected to the transmission element located on the side of the   dragging by means of a damping system provided with   energy accumulators in the form of torsion springs, the different torsion springs being arranged radially in one another and at least one control element being associated with each transmission element for at least one of the accumulators of energy, characterized in that   the torsional stress of the radial torsion spring (22)   outermost is smaller than constraint   torsion of at least one of the torsion springs (24)   internally housed in this torsion spring (22) the more outside.   2) Torsional oscillation damper according to the claim   tion 1, characterized in that the distance between respectively two windings (26) of the   internal torsion spring (24) is, at least in the state   loaded, larger than that between respectively   two turns (25) of the external torsion spring (22).   3) Torsional oscillation damper according to the claim tion 1, characterized in that   the torsional stress of the radial torsion spring (22)   the outermost is reduced until even in the case of excessive bending stress in the turns (25) the overall stress which can withstand without damage these are not exceeded.   4) Torsional oscillation damper comprising an element   transmission side located on the drive side and a   transmission element located on the side of the power take-off   which can therefore be articulated on the same axis, and which   is connected to the transmission element located on the side of the   dragging by means of a damping system provided with   energy accumulators in the form of torsion springs, the different torsion springs being arranged radially in one another and at least one control element being associated with each transmission element for at least one of the accumulators of energy, characterized in that   the torsional torque / elastic force of the torsion spring   radially outermost (22) is less than or equal to the torsional torque / elastic force of at least one of the radially inner torsion springs (24), which   is housed in this outermost torsion spring (22).