WO2016073842A1

WO2016073842A1 - Rotational vibration damper and drive train for a motor vehicle with a rotational vibration damper of this type

Info

Publication number: WO2016073842A1
Application number: PCT/US2015/059449
Authority: WO
Inventors: Florian Schneider; Viren Saxena; Hans Juergen Hauck; Matthias Werner; Jochen Boelling
Original assignee: Borgwarner Inc.
Priority date: 2014-11-08
Filing date: 2015-11-06
Publication date: 2016-05-12
Also published as: EP3215758A4; EP3215758A1; DE102014016573A1; CN107002816B; CN107002816A

Abstract

The present invention relates to a rotational vibration damper (2) comprising a base part (18) rotatable around an axis of rotation (16) and an inertial mass part (20) which is rotatable relative to the base part (18) and counter to the reset force of a reset device (36), wherein the reset device (36) has a spring unit (38) for generating a set force. The reset device (36) has at least one pivotable lever element (40) pivotable around a pivot point (46), via which lever element the set force is transmittable from a set force engagement point (42) of the lever element (40) to the inertial mass part (20) by generating the reset force affecting the inertial mass part (20) via a reset force engagement point (44) of lever element (40). The present invention further relates to a drivetrain (110) for a motor vehicle with a rotational vibration damper (2) of this type.

Description

ROTATIONAL VIBRATION DAMPER AND DRIVE TRAIN FOR A MOTOR VEHICLE WITH A ROTATIONAL VIBRATION DAMPER OF THIS TYPE

Description The present invention relates to a rotational vibration damper comprising a base part rotatable around an axis of rotation and an inertial mass part which is rotatable relative to the base part and counter to the reset force of a reset device, wherein the reset device has a spring unit for generating a set force. The present invention further relates to a drivetrain for a motor vehicle with a rotational vibration damper of this type.

A rotational vibration damper is known from DE 199 07 216 CI which has a base part in the form of a support plate rotatable around an axis of rotation. An inertial mass is arranged on the support plate which is rotatable counter to the reset force of a reset device relative to the base part. The reset device has a

flexible spring which extends in a radial direction and which is arranged on the one hand on the base part and on the other hand on the inertial part. The flexible spring functions to generate a set force which directly affects the inertial mass if the inertial mass is rotated

relative to the base part such that the set force equally represents the reset force affecting the inertial mass. The support of the inertial mass in the radial direction on the support plate is carried out on the side of the support plate facing outward in the radial direction, wherein bearing shells are arranged for this purpose on the support plate, on which bearing shells the inertial mass is supported in the radial direction and guided in the circumferential direction. The known rotational vibration damper is disadvantageous insofar as that a relatively large and installation space intensive

flexible spring is necessary for the reset device, particularly as this reset device must be arranged on the one hand on the inertial mass and on the other hand on the support plate. The last-stated necessity of

supporting the flexible spring on the one hand on the support plate and on the other hand on the inertial mass also has the result that the arrangement of the flexible spring on the rotational vibration sensor is largely predefined. Consequently, no flexible arrangement of the flexible spring is possible in rotational vibration dampers of the type described. In addition, the support of the inertial mass in the radial direction outward on the support plate via the mounting shells on the support plate requires that the rotational vibration damper has a relatively complex structure, wherein in addition an increased wear occurs in the area of the support of the inertial mass at the support plate.

Starting from this prior art, the underlying problem of the present invention is to create a

rotational vibration damper which has a simplified and installation space saving structure, wherein a

particularly flexible arrangement of the spring unit should be possible. In addition, the underlying problem of the present invention is to create a drivetrain for a motor vehicle with an advantageous rotational vibration damper of this type.

This problem is solved by the features listed in Claim 1 or Claim 12. Advantageous embodiments of the invention are the subject matter of the subclaims. The rotational vibration damper according to the invention has a base part rotatable around an axis of rotation. The base part may for example be formed from a base plate or support plate extending substantially in the radial direction, if necessary a double base plate or double support plate. In addition, the rotational

vibration damper has an inertial mass part which may be rotated around the axis of rotation counter to the reset force of a reset device relative to base part. The reset device has a spring unit for generating a set force, wherein the spring unit may have, for example, one or multiple spring elements. In addition, the reset device has a lever element pivotable around a pivot point. Thus, the pivotable lever element may, for example, be pivoted indirectly via the pivot point or directly on the base part. It is hereby preferred if the lever element [runs] in a plane spanned by the radial directions of the rotational vibration damper and is consequently pivotable around an axis extending through the pivot point in the axial directions of the rotational vibration damper. In addition, the pivotable lever element is preferably a bend-proof or rigid lever element. The lever element is arranged between the spring unit on the one side and the inertial mass part on the other side in such a way that the set force generated by the spring unit may be

transmitted from a set force engagement point on the lever element to the inertial mass part while generating the reset force affecting the inertial mass part via a reset force engagement point of the lever element. This has the advantage that the spring unit of the reset device generating the set force does not have to directly affect the inertial mass part, but instead may be

arranged in fact at another point on the base part of the rotational vibration damper, by which means a space- saving and flexible arrangement of the spring unit on the rotational vibration damper is possible. On the other hand, a lever ratio may be set or specified due to the lever element, based on which the reset force acting on the inertial mass part is greater or smaller than the set force generated by the spring unit of the reset device. Thus, the stiffness of the reset device may be increased in a targeted way by specifying the lever ratio without necessitating a particularly stiff spring unit for generating the set force. It should thus initially be recorded that the spring unit has only a low spring rigidity and consequently may be formed in an especially installation space-saving way, wherein in addition a flexible arrangement of the spring unit on the base part of the rotational vibration damper is possible. In a preferred embodiment of the rotational vibration damper according to the invention, the lever element is supported or is supportable on the base part on the one side via a support track on the base part or on the lever element and on the other side via a

rotatable roller unit rollable along the support track on the lever element or on the base part. The support is carried out here preferably substantially in the radial direction. Due to the roller unit, a vanishingly low wear is achieved between the lever element and the base part in this embodiment when the lever element is pivoted around the pivot point, wherein an equally secure support of the lever element on the base part is still

guaranteed. The support track in connection to the roller unit may be provided in this embodiment for example in the area of the pivot point. Alternatively or

supplementally, the support track in connection to the roller unit may be provided in the area of the set force engagement point, as this shall be subsequently explained in more detail. Thus, the set force engagement point in a particularly preferred embodiment of the rotational vibration damper according to the invention is moveable along the support track by rotating the inertial mass part relative to the base part. Consequently, the support track or roller unit in this embodiment interacts with the roller unit or the support track at the set force engagement point. By this means, a particularly simple structure may be achieved, which additionally ensures the already previously mentioned low wear between the lever element and the base part during pivoting of the lever element .

Basically, the previously mentioned roller unit may be formed by a simple wheel or a simple roller, which on the one side is arranged rotatable yet fixed on the lever element or base part and on the other side is rollable on the support track of the base part or lever element. In a further preferred embodiment of the

rotational vibration damper according to the invention, the roller unit is formed essentially by a roller bearing in order to achieve the previously mentioned advantages and to achieve an equally compact structure. Thus, the roller bearing may preferably have an inner race, an outer race, and rolling elements arranged between the inner race and the outer race. The inner race is thereby preferably fixed and if necessary arranged as non- rotating on the lever element or base part, while the outer race is rollable on the support track of the base part or lever element due to the rolling elements between the inner- and outer races. The roller bearing is preferably a needle bearing in order to achieve a

loadable and equally compact structure of the roller unit . In an advantageous embodiment of the rotational vibration damper according to the invention, the spring unit has at least one helical spring for generating the set force. The helical spring which may be for example a helical compression spring and/or a helical tension spring, is arranged in a recess on the base part.

In a further advantageous embodiment of the rotational vibration damper according to the invention, at least one displaceable support shoe is arranged on the helical spring in the recess, in which the at least one helical spring is arranged, wherein the helical spring is supported or is supportable outwardly in the radial direction via the support shoe on a support side of the recess facing the helical spring. The support shoe consequently has the advantage that the helical spring is not supported or is not supportable directly on the support side of the recess such that a potential rubbing wear on the helical spring or on the support side of the recess is minimized. The wear may also be reduced by suitable selection of the material for the support shoe, wherein the support shoe is preferably produced from a plastic, whereas the helical spring and/or the support side of the recess are formed particularly preferably from metal or steel. A roller unit might also function between the support shoe and the support side of the recess in an advantageous way in order to significantly reduce the wear between the support shoe and the support side of the recess, as this is the case in a further advantageous embodiment of the rotational vibration damper according to the invention. Thus, correspondingly rotatable rollers which are rollable on the support shoe might be provided for example on the support shoe itself. Basically, the support shoe might extend only in the interior space of the helical spring surrounded by the windings of the helical spring in order to affect by this means a support on the support side of the recess. In a particularly advantageous embodiment of the

rotational vibration damper according to the invention, the support shoe extends alternatively or supplementally between the outer periphery of the helical spring and the support side of the recess in order to effect a

particularly secure support. A helical spring might also be discussed hereby which is supported or is supportable on the support side of the recess by an intermediate placement of the support shoe, or at least a support shoe section, between the outer periphery of the helical spring and the support side of the recess. In a further preferred embodiment of the rotational vibration damper according to the invention, the support shoe is arranged between the outer periphery of the helical spring and the support side of the recess, while creating a clearance between the support side of the recess and the outer periphery of the helical spring in an area of the helical spring between the support shoe on the one side and another support shoe or a support point of the helical spring on the base part on the other. The support point hereby designates preferably the end side support point for supporting the helical spring on the base part, wherein this may be also be carried out, if necessary, by a support shoe. This embodiment has the advantage that the helical spring may bend

transversely to the extension direction thereof as a result of centrifugal forces at high rotational speeds of the rotational vibration damper, without the helical spring coming into contact with the support side of the recess, particularly as the helical spring may bend or extend into the previously mentioned clearance. The clearance or the dimensions thereof are hereby preferably selected in such a way that a contact between the outer periphery of the helical spring and the support side of the recess does not occur if the rotational vibration damper is driven within the drivetrain at the maximum rotational speed.

The previously mentioned support shoe may basically be arranged everywhere within the recess in order to enable the support of the helical spring on the support side of the recess by means of the support shoe. In a further preferred embodiment of the rotational vibration damper according to the invention, the support shoe is, however, arranged and formed in such a way that the set force of the spring unit may be transmitted to the set force engagement point of the lever element via the support shoe. Thus, the support shoe may be formed for example as an end shoe for the helical spring, which interacts with the end side of the helical spring in order to be able to transmit the set force of the spring unit to the set force engagement point. As already previously mentioned, still other support shoes are, however, conceivable, which do not transmit the set force of the spring unit to the set force engagement point, but instead merely function to support the helical spring on the support side of the recess or the previously

mentioned support point.

In a further particularly preferred embodiment of the rotational vibration damper according to the invention, the support shoe, together with the lever element, is supported or is supportable on the base part via the roller unit and the support track. As already previously indicated, the support shoe, together with the lever element, is supported or is supportable thereby on the base part preferably in the area of the set force engagement point via the roller unit and the support track. This embodiment has, on the one hand, the advantage that the wear is reduced by the support across the roller unit and the support track, which results in a lower rubbing wear on the support shoe and guarantees simple movability of the support shoe. On the other hand, an already mentioned second function is assigned to the already present roller unit and support track, namely the additional support of the support shoe on the base part such that no additional roller unit or support track is necessary, at least in this area, which significantly simplifies the structure of the rotational vibration damper .

In a further advantageous embodiment of the rotational vibration damper according to the invention, the spring unit has two helical springs which function counter to each other on the lever element. Thus for example two helical compression springs or two helical tension springs may be provided. However, it is likewise possible to form both helical springs as helical tension and compression springs.

If the spring unit has two helical springs for achieving the set force, then the previously mentioned support shoe forms, in a further advantageous embodiment of the rotational vibration damper according to the invention, the support shoe for the one helical spring as well as the support shoe for the other helical spring. In this way, not only is the number of parts reduced, instead, in particular if the support shoe is a support shoe which transmits the set force to the set force engagement point of the lever element, an exact interplay is guaranteed for the two helical springs generating the set force. In this embodiment, it is further preferred if the support shoe is formed as one piece, wherein the support shoe, as previously indicated, is preferably produced from plastic. In a further advantageous embodiment of the rotational vibration damper according to the invention, the center of mass of the lever element is arranged on a level with the set force engagement point or further outward in the radial direction than the set force engagement point.

In a further preferred embodiment of the rotational vibration damper according to the invention, which embodiment particularly - however not exclusively - develops advantages in embodiments, in which the reset force engagement point retains the relative arrangement thereof with respect to the lever element, and which shall be discussed in more detail later, the center of mass of the lever element is arranged further outward in the radial direction than the pivot point. This has the advantage that the lever element tends to return to the starting pivot position thereof solely based on

centrifugal force. It is thereby further advantageous if the center of mass of the lever element is arranged at least on a level with the reset force engagement point in the radial direction, preferably further outward in the radial direction than the reset force engagement point, in order to amplify still more the previously mentioned advantage .

In a further advantageous embodiment of the rotational vibration damper according to the invention, the center of mass of the lever element arranged further outward than the pivot point, at least in the axial direction, is arranged on a common line or radial with the pivot point and/or the reset force engagement point and/or the set force engagement point, when viewed in the axial direction. The listed center of mass of the lever element is thereby preferably arranged in the starting position of the lever element or of the inertial mass part on a common radial with the pivot point and/or the reset force engagement point and/or the set force

engagement point. By this means, the centrifugal force has no, or merely a minor, influence on the lever element if the lever element is located in the starting position thereof .

In a further preferred embodiment of the rotational vibration damper according to the invention, the lever element has a lever part formed preferably elongated and a lever mass part. The lever mass part is fixed on the lever part while arranging the center of mass of the lever element further outward in the radial direction than a center of mass of the lever part. The lever mass part is thereby preferably formed

intrinsically with the lever part or separately from the lever part. The lever mass part formed intrinsically with the lever part has the advantage of a simplified

manufacture, particularly as the lever mass part may be co-produced over the course of the production of the lever part. The lever mass part formed separately from the lever part has, in contrast, the advantage that this may be applied subsequently to the already produced lever part in order to subsequently position the center of mass of the entire lever element in a targeted way by applying the lever mass part on the lever part. With regard to the lever mass part formed separately from the lever part, it is further preferred if this is detachably or non- detachably fixed to the lever part via a fastening point. It is also preferred in this case if the lever mass part is fixable on at least two different fastening points and/or is flexibly positionable along the lever part in order to be able to still subsequently influence the center of mass of the lever element. In order to be able to support or mount the inertial mass part on the base part in the radial

direction particularly securely and without large

friction losses, the inertial mass part is supported or is supportable on the base part in the radial direction by at least three rollers in a further particularly preferred embodiment of the rotational vibration damper according to the invention. In a further preferred embodiment of the rotational vibration damper according to the invention, the rollers are rotatably fixed on one side on the inertial mass part or base part and are rollable on the other side on the base part or inertial mass part. The fixing of the rollers on the inertial mass part or base part may be effected here for example via a roller bracket on the inertial mass part or base part such that the rollers are carried along by the roller bracket during a rotation of the inertial mass part or base part relative to the base part or inertial mass part, however, are rollable on the base part or inertial mass part. It is hereby preferred if the rollers are arranged fixed on the inertial mass part or base part with respect to the circumferential direction.

In a further preferred embodiment of the rotational vibration damper according to the invention, the previously mentioned rollers are rollable on a roller track on the base part or inertial mass part, wherein the roller track is arranged outside of a peripheral circle in the radial direction, the radius of which is 80%, if necessary 90% of the largest radius of the base part. In this way it is guaranteed that the rollers may be

arranged further outward in the radial direction, without requiring that these be supported across a long roller bracket extending in the radial direction, such that the structure of the rotational vibration damper is

simplified and the weight thereof is reduced. It is hereby particularly advantageous if the roller track is provided on the largest radius of the base part while the rollers are preferably provided on the inertial mass part. If, in contrast, the rollers are provided on the base part, then it is preferred if the roller track provided on the inertial mass part is provided outside of the base part in the radial direction, consequently at a radius which is greater than the largest radius of the base part.

As previously indicated a secure and largely wear-free support of the inertial mass part on the base part in the radial direction is achievable via the rollers and thus a mounting of the inertial mass part on the base part. In a further advantageous embodiment of the rotational vibration damper according to the

invention, the inertial mass part is further supported or is further supportable in at least one axial direction, preferably in both axial directions via at least one of the rollers. Consequently, a double function is assigned to the rollers in this embodiment, which on the one side produces the support in the radial direction and on the other side the support in the axial direction between the inertial mass part and the base part such that the structure may be further simplified, particularly as no further or additional means are necessary for supporting the inertial mass part on the base part in the axial direction.

In a further advantageous embodiment of the rotational vibration damper according to the invention, a peripheral groove is provided in the outer side in at least one of the rollers fixed to the inertial mass part or the base part, into which groove the base part or inertial mass part extends. This embodiment has the advantage that the peripheral groove in the roller or in the rollers may be created relatively easily within the context of producing the rollers, by which means the production of the rotational vibration damper as a whole is simplified.

In a further preferred embodiment of the rotational vibration damper according to the invention, a groove is provided in the base part or in the inertial mass part, into which the roller extends in order to produce the support of the inertial mass part in at least one axial direction, preferably in both axial directions. In a further advantageous embodiment of the rotational vibration damper according to the invention, the lever element has a first lever section between the set force engagement point and the pivot point and a second lever section between the pivot point and the reset force engagement point, the lengths of which may be changed by rotating the inertial mass part relative to the base part while substantially maintaining the lever ratio . In a further advantageous embodiment of the rotational vibration damper according to the invention, the pivot point and the reset force engagement point may be moved relative to the lever element by changing the length of the lever sections, while the set force

engagement point retains the relative arrangement thereof with respect to the lever element. It has been shown that in this embodiment variant, the influence of the

centrifugal force on the position of the lever element at high rotational speeds of the rotational vibration damper is reduced, and the lever element may be returned

relatively easily back to the starting position thereof. In addition, it is preferred in this embodiment if the set force engagement point is arranged closer to the axis of rotation, relative to the radial direction, than is the case for the pivot point. It might also be stated that it is preferred in this embodiment if the radial distance between the set force engagement point and the axis of rotation is smaller than the radial distance between the pivot point and the axis of rotation. In a further advantageous embodiment of the rotational vibration damper according to the invention, which shows an alternative to the previously described embodiment, the pivot point and the set force engagement point may be moved relative to the lever element by changing the length of the lever sections, while the reset force engagement point retains the relative

arrangement thereof with respect to the lever element. This embodiment is advantageous in particular in

connection with a previously described embodiment, according to which the center of mass of the lever element is arranged further outward in the radial

direction than the pivot point, preferably at least at a level with the reset force engagement point in the radial direction, particularly preferably further outward in the radial direction than the reset force engagement point, in order to achieve the previously mentioned advantages.

In a further preferred embodiment of the rotational vibration damper according to the invention, the reset force engagement point is adjustable by

changing a reset force characteristic curve of the reset force. Thus, for example, the gradient of the reset force characteristic curve of the reset force affecting the inertial mass part may be increased or reduced by

adjusting the reset force device such that

correspondingly the stiffness of the reset force device is increased or reduced. Consequently, a reset force device is created which may react flexibly to operating states within a drivetrain. In a further advantageous embodiment of the rotational vibration damper according to the invention, the lever ratio of the lever element may be changed by changing the reset force characteristic curve of the reset force. In this embodiment, it is preferred if the pivot point may be adjusted by changing the lever ratio of the lever element, consequently [it] is changeable in the position thereof relative to the base part. Thus, the pivot point may be arranged for example moveable on the base part, wherein a movement of the pivot point in the radial direction relative to the base part or along a radial is preferred. In addition, it is preferred in this embodiment if the pivot point is formed by a protruding projection arranged adjustably or displaceably on the base part.

In a further particularly advantageous embodiment of the rotational vibration damper according to the invention, the center of mass of the lever element is arranged further outward in the radial direction than the pivot point in at least one set position of the adjustable pivot point or regardless of the set position of the pivot point, in order to achieve the already previously mentioned advantages of a center of mass of the lever element arranged further outward in the radial direction than the pivot point.

The drivetrain according to the invention for a motor vehicle has a rotational vibration damper of the type according to the invention, the base part of which is mounted rotationally fixed on a component of the drive train. The base part may thereby be basically fixed to any component of the drivetrain which is subjected to rotational vibrations.

In a preferred embodiment of the drivetrain according to the invention, the component, on which the base part of the rotational vibration damper is mounted rotationally fixed, is the input side of a torsional vibration damper or dual mass flywheel, the output side of a torsional vibration damper or dual mass flywheel, the input side of a clutch device, if necessary an input side disk carrier or a radial support section of an input side disk carrier, the output side of a clutch device, the input side of a transmission, and/or the output side of a transmission. Two or more rotational vibration dampers may absolutely be provided hereby which

respectively affect one of the previously mentioned points within the drivetrain.

In a particularly preferred embodiment of the drivetrain according to the invention, the output side of a clutch device is an output-side disk carrier or a radial support section of an output-side disk carrier, on which the base part is mounted rotationally fixed which increases the engine speed strength of the output-side disk carrier or the radial support section of the output- side disk carrier. Correspondingly, the base part is mounted rotationally fixed on the output-side disk carrier or the radial support section of the output-side disk carrier while reinforcing the output-side disc- carrier or the radial support section of the output-side disk carrier.

The invention will subsequently be explained in more detail by means of exemplary embodiments with reference to the accompanying drawings. Shown are: Figure 1 a front view of an embodiment of the rotational vibration damper according to the invention with the lever part in a starting position,

Figure 2 the rotational vibration damper from

Figure 1 with the lever element pivoted out of the starting position, Figure 3 a partial view of the rotational

vibration damper from Figures 1 and 2 along Line A-A in a first embodiment variant , Figure 4 a partial view of the rotational

vibration damper from Figures 1 and 2 along Line A-A in a second embodiment variant , Figure 5 a schematic representation of an

embodiment of a drivetrain with at least one rotational vibration damper according to Figures 1 through 4. Figures 1 and 2 show an embodiment of the rotational vibration damper 2 according to the invention. In the figures, the opposite axial directions 4, 6, the opposite radial directions 8, 10, and the opposite circumferential directions 12, 14, which may also be designated as opposing rotational directions, of

rotational vibration damper 2 are indicated by

corresponding arrows. Rotational vibration damper 2 has an axis of rotation 16 extending in axial directions 4, 6.

Rotational vibration damper 2 has a base part 18 rotatable around axis of rotation 16 in circumferential directions 12, 14. Base part 18 may be formed for example as plate shaped or double-plate shaped, wherein base part 18 preferably extends in the plane spanned by radial directions 8, 10, here the plane of the drawing. Base part 18 may, for example in the area of axis of rotation 16, be connected rotationally fixed to a component within the drivetrain in order to damp the rotational vibrations to which the component is

subjected. The components of the drivetrain, on which base part 18 may be mounted rotationally fixed, will be discussed later in more detail with reference to Figure 5. Rotational vibration damper 2 further has an inertial mass part 20, wherein inertial mass part 20 is formed with an annular shape. Inertial mass part 20 is supported or is supportable on base part 18 in radial direction 8 via at least three rollers 22. Rollers 22 are thereby spaced at a uniform distance from each other in circumferential direction 12, 14. In the embodiment shown, rollers 22 are fixed on inertial mass part 20 in such a way that they are rotatable in circumferential direction 12, 14, together with inertial mass part 20, relative to base part 18. It may thus be stated that rollers 22 are arranged fixed on inertial mass part 20 with respect to circumferential direction 12, 14.

Nevertheless, rollers 22 are rotatably fixed on inertial mass part 20. Thus rollers 22 may each be rotated around a roller axis 24 extending in axial directions 4, 6. In contrast, a roller track 26 is provided on base part 18, on which rollers 22 are rollable, preferably across the outer side 28. Base part 18 has a largest radius ri , which may be designated as the maximum radius of base part 18, wherein roller track 26 is arranged in radial direction 8 outside of a peripheral circle 30, the radius r2 of which is 80%, if necessary 90%, of the largest radius ri of base part 18. In the embodiment shown, roller track 26 is provided on a level with or at the largest radius ri of base part 18. Supplementally, reference is made at this point to the fact that a reversed arrangement is also possible. Thus, rollers 22 may also or supplementally be rotatably fixed on base part 18, while roller track 26 is provided on inertial mass part 20, on which rollers 22 are rollable. In this embodiment variant, roller track 26 might thus also be arranged in radial direction 8 outside of base part 18 or a peripheral circle with the largest radius ri.

Inertial mass part 20 is further supported or is further supportable on base part 18 in at least one of axial directions 4, 6, preferably in both axial

directions 4 and 6, via at least one roller 22. Thus, in a first embodiment variant, which is shown in Figure 3, a peripheral groove 32 is provided on the outer side 28 in at least one of the rollers 22 fixed on inertial mass part 20 or base part 18, into which groove the base part 18 extends in radial direction 8 in order to affect a positive-locking fixing of inertial mass part 20 in axial directions 4, 6 on base part 18. In Figure 3, the variant is thereby shown, in which rollers 22 are rotatably fixed on inertial mass part 20, while roller track 26 is provided on base part 18. Alternatively or

supplementally, a groove 34 may be provided in base part 18 or inertial mass part 20, wherein this second

embodiment variant is shown in Figure 4. In this second embodiment variant, roller 22 extends in radial direction 10 into groove 34 on base part 18 or inertial mass part 20, wherein Figure 4 also shows the embodiment, in which rollers 22 are rotatably fixed on inertial mass part 20, while roller track 26 is provided on base part 18.

Reference is again made at this point that the two embodiment variants according to Figures 3 and 4 may be used in analogous way in a constellation in which rollers 22 are rotatably fixed on base part 18, while roller track 26 is provided on inertial mass part 20.

As is evident from Figure 1, rotational vibration damper 2 further has two reset devices 36 which are arranged diametrically opposite each other and/or spaced at a uniform distance from each other in

circumferential directions 12, 14 on rotational vibration damper 2. Reset devices 36 are thereby designed

substantially identical in construction such that reset device 36 is subsequently described with reference to only one of the reset devices 36, wherein the description equally applies for the other reset devices 36. Reference is also made to the fact that rotational vibration damper 2 may absolutely have three or more reset devices 36 of the subsequently described type, wherein these reset devices 36 should then likewise be spaced at a uniform distance from each other in circumferential direction 12, 14.

Reset device 36 has a spring unit 38 for generating a set force and a pivotable lever element 40, via which the set force of spring unit 38 may be

transmitted to inertial mass part 20 from a set force engagement point 42 of lever element 40 by generating the reset force affecting inertial mass part 20 via a reset force engagement point 44 of lever element 40. In other words, inertial mass part 20 is rotatable around axis of rotation 16 in circumferential direction 12, 14 relative to base part 18 counter to the reset force of reset device 36. Lever element 40 is pivotable relative to base part 18 around a fixed pivot point 46. Consequently, lever element 40 may be pivoted relative to base part 18 around a pivot axis extending in axial directions 4, 6. Pivot point 46 may thereby be formed for example by a protruding protection on base part 18. Pivot point 46 is displaceable relative to base part 18 along a

displacement path 48 extending in a straight line in radial direction 8, 10, wherein to form displacement path 48, for example a corresponding guide for the protruding projection forming pivot point 46 may be provided on base part 18. If pivot point 46 is formed by a protruding projection of this type on base part 18, then the

projection extends preferably in axial direction 4, 6 in a guide 50 in lever element 40, which guide extends in the extension direction of lever element 40 and is formed here as an elongated recess.

Lever element 40 has a first lever section 52 between set force engagement point 42, at which the set force from spring unit 38 is transmitted to lever element 40, and pivot point 46. In addition, lever element 40 has a second lever section 54, which extends between pivot point 46 and reset force engagement point 44, wherein the reset force resulting from the set force of spring unit 38 affects inertial mass part 20 via reset force

engagement point 44. First lever section 52 has a length li, while second lever section 54 has a length 1₂.

Consequently, lever element 40 has a lever ratio li / 1₂ in the sense that liis divided by 1₂. The two lengths li and 1₂ may be changed, consequently increased or reduced, by rotating inertial mass part 20 around axis of rotation 16 relative to base part 18, as this is shown in Figure 2, substantially maintaining the lever ratio li / 1₂. For this purpose, in the embodiment shown, on the one hand pivot point 46 is displaceable relative to lever element 40, as this was previously described with reference to the protruding projection forming pivot point 46 and guide 50. On the other hand, reset force engagement point 44 is

displaceable relative to lever element 40 in the

extension direction of lever element 40. The latter is effected, for example, in that a protruding projection on inertial mass part 20 forming reset force engagement point 44 is arranged in a guide 56 within lever element 40, wherein guide 56 extends, like guide 50 already does, in the extension direction of lever element 40 and here is formed by way of example as an elongated recess in lever element 40. Set force engagement point 42

maintains, in contrast, the relative arrangement thereof with respect to lever element 40, when lever element 40 is pivoted around pivot point 46. However, at least set force engagement point 42 is arranged fixed on lever element 40 with respect to the extension direction of lever element 40. Even if the embodiment shown is

preferred, alternatively pivot point 46 and set force engagement point 42 may be formed moveable relative to lever element 40 by changing lengths li, I2 of lever section 52, 54, while reset force engagement point 44 retains the relative arrangement thereof with respect to lever element 40. In this case, guide 56 may be assigned to set force engagement point 42. Then, the support tracks and roller units described later in more detail may also be omitted.

Reset device 36 may be adjusted by changing a reset force characteristic curve of the reset force affecting inertial mass part 20. In the embodiment shown, the lever ratio li / I2 of lever element 40 is changeable for this purpose, in that pivot point 46 adjusts or is displaceable relative to base part 18 along the

previously mentioned displacement path 48 outward in radial direction 8 or inward in radial direction 10 while changing the lever ratio li / I2 of lever element 40. For this purpose, a corresponding reset device may be

provided which may adjust or displace pivot point 46 in a mechanical or hydraulic way along displacement path 48, wherein a representation of a reset device was omitted in the drawings for reasons of clarity. In any case, the adjustability of reset device 36, by changing the reset force characteristic curve of the reset force affecting inertial mass 20, enables rotational vibration damper 2 to be able to flexibly react to different operating states within the drivetrain or rotational vibration damper 2 through corresponding adjustment of reset device 36. Lever element 40 has an elongated lever part

58 and a lever mass part 60 arranged on lever part 58. Lever part 58 has a center of mass 62 while lever mass part 60 has a center of mass 64. Lever mass part 60 is thereby arranged on lever part 58 in such a way that a center of mass 66 of lever element 40, which is composed of lever part 58 and lever mass part 60, is arranged further outward in radial direction 8 than center of mass 62 of lever part 58. Lever mass part 60 may be formed intrinsically with lever part 58. Alternatively, lever mass part 60 may be formed separately from lever part 58 in order to be detachably or non-detachably fixed on lever part 58 via a fastening or fastening point. With regard to lever mass part 60 formed initially separately, it is further preferred if the positioning of lever mass part 60 on lever part 58 is changeable at least with respect to radial directions 8, 10 or the extension direction of lever part 58, in order to enable a

subsequent exact setting of center of mass 66 of lever element 40, which is composed from lever mass part 60 and lever part 58. Center of mass 66 of lever element 40 is arranged in radial direction 8 either at a level with set force engagement point 44 or - as shown in Figures 1 and 2 - farther outward in radial direction 8 than set force engagement point 44. Stated more exactly, center of mass 66 is arranged further outward in radial direction 8 than pivot point 46. Since pivot point 46 in the embodiment shown is displaceable or moveable along displacement path 48 in radial direction 8, 10 by changing the reset force characteristic curve, it should be taken into

consideration that center of mass 66 of lever element 40 is arranged, at least in a set position of pivot point 46, further outward in radial direction 8 than pivot point 46 in this set position. It is, however,

additionally preferred if center of mass 66 of lever element 40 is arranged further outward in radial

direction 8 than pivot point 46 regardless of the

respective set position of pivot point 46. It is, however, likewise possible to specify the center of mass 66 of lever element 40 in such a way that pivot point 46 in the outermost set position thereof in radial direction 8 is arranged at a level with center of mass 66 of lever element 40 with respect to radial directions 8, 10. In the embodiment shown, center of mass 66 is not only arranged further outward in radial direction 8 than pivot point 46, regardless of the set position of pivot point 46, center of mass 66 of lever element 40 is instead arranged further outward in radial direction 8 than reset force engagement point 44, wherein it would be likewise possible here to arrange center of mass 66 of lever element 40 at a level with reset force engagement point 44 in radial direction 8, 10. By using the previously described arrangement alternatives for center of mass 66 of lever element 40, the influence of a centrifugal force affecting lever element 40 at a high rotational speed of rotational vibration damper 2 is optimized or changed to the effect that lever element 40, based on the

centrifugal force alone, already tends to return to the starting position shown in Figure 1, wherein this

behavior is supported to a special degree by the

arrangement, shown in Figures 1 and 2, of center of mass 66 further outward in radial direction 8 than reset force engagement point 44. It is also evident from Figures 1 and 2 that center of mass 66 of lever element 40 is arranged, when viewed in axial direction 4, 6, on a common line 68 with pivot point 46, reset force

engagement point 44, and set force engagement point 42, wherein this line 68 preferably corresponds to a radial in the starting position of lever element 40 according to Figure 1. In any case, center of mass 66 of lever element 40 should be arranged on a common line 68 at least with pivot point 46 and set force engagement point 42.

Lever element 40 is supported or is supportable on base part 18 in radial direction 8 and radial direction 10 via at least one support track 70, 72 on base part 18 on the one side and via a rotatable roller unit 74 rollable along support track 70, 72 on base part 18 on the other side. Stated more exactly, set force engagement point 42 is moveable relative to base part 18 along support tracks 70, 72 by rotating inertial mass part 20. In the embodiment shown, roller unit 74 is rotatably fixed on lever element 40 at set force

engagement point 42. Thus, roller unit 74 in the

embodiment shown is formed as a roller bearing,

preferably a needle bearing, the inner race 76 thereof is mounted fixedly to a protruding projection of lever element 40 forming set force engagement point 42, wherein rolling elements 78 are arranged between inner race 76 and an outer race 80 of the roller bearing, and outer race 80 is supportable and rollable on previously

mentioned support tracks 70, 72. Roller unit 74, which is formed here in the form of a roller bearing, is arranged in a guide 82 which is formed here as an elongated recess, indicated merely by dashed lines as part 84, wherein part 84 may be formed intrinsically with base part 18 or may be fixed as a separate part on base part 18. Support track 70 forms the boundary of guide 82 outward in radial direction 8, while support track 72 represents the boundary of guide 82 inward in radial direction 10. Due to roller unit 74, the wear in the area of set force engagement point 42 between lever element 40 on the one side and base part 18 on the other side, which may occur during pivoting of lever element 40 or during rotation of inertial mass part 20 relative to base part 18, is significantly reduced. It should be mentioned at this point that roller unit 74 may also be more simply designed, thus may be formed for example as a rotatable wheel or a rotatable roller, which is supported or is supportable on corresponding support track 70, 72. It should additionally be noted that the arrangement shown may also be carried out in reverse, such that guide 82 including support tracks 70, 72 is provided on lever element 40, whereas roller unit 74 may be arranged on base part 18.

Spring unit 38 of reset device 36 has two helical springs 86, 88, which are here formed as helical compression springs. The two springs 86, 88 function counter to each other on lever element 40 or set force engagement point 42 of lever element 40. Thus, the two helical springs 86, 88 are respectively supported on the one side on a support point 90, 92 on base part 18, for example via a support shoe formed as an end shoe, and on the other side on set force engagement point 42. The two helical springs 86, 88 are thereby respectively arranged in a recess 94 of base part 18, wherein recesses 94 for helical springs 86, 88 are preferably formed as

continuous recess 94. Recesses 94 respectively have a support side 96 which faces the respective helical spring 86, 88 inward substantially in radial direction 10.

Helical springs 86, 88 are respectively supported or are respectively supportable thereby via a support shoe 98, which is arranged on helical springs 86, 88 outward in radial direction 8 on support side 96. It is evident from Figures 1 and 2 that support shoe 98 is formed as an end shoe for each of the two helical springs 86, 88

respectively, wherein support shoe 98 forms the support shoe for the one helical spring 86 as well as the support shoe for the other helical spring 88. Support shoe 98 is formed as one piece in the embodiment shown and is preferably produced from plastic.

Support shoe 98 has a center section 100, which is arranged in the extension direction of the two helical springs 86, 88 between helical springs 86, 88. In addition, support shoe 98 has a first section 102

connected to center section 100, which first section extends between the outer periphery of helical spring 86 and support side 96, and a second section 104 connected to center section 100, which second section extends, starting from center section 100, between the outer periphery of helical spring 88 and support side 96. In other words, first section 102 is arranged between the outer periphery of helical spring 86 and support side 96, while second section 104 is arranged between the outer periphery of helical spring 88 and support side 96. This is carried out while creating a clearance 106 between the respective support side 96 and the outer periphery of the respective helical spring 86, 88 in the area of helical springs 86, 88 between support shoe 98 on the one side and support point 90, 92 of helical springs 86, 88 on the other side. Basically still more support shoes might be provided within recess 94 on the respective helical springs 86, 88, wherein clearance 106 in this case might also be formed between support shoe 98 on the one side and the additional support shoe on the other side.

Clearance 106 enables a bending of helical springs 86, 88 outward in radial direction 8 into clearance 106 at high rotational speeds, without a contact occurring between the respective helical springs 86, 88 and associated support side 96 of recess 94, by which means helical springs 86, 88 may fulfill the function thereof

unhindered and wear on recess 94 or on the respective helical spring 86, 88 is prevented.

The set force of spring unit 38 formed by helical springs 86, 88 is transmitted to set force engagement point 42 via support shoe 98. For this

purpose, a projection on lever element 40 forming set force engagement point 42 may extend for example through a corresponding recess or opening in support shoe 98. Regardless of the respective linking of support shoe 98 at set force engagement point 42, support shoe 98, together with lever element 40, is supported or is supportable on part 84 of base part 18 via roller unit 74 and support track 70, 72. In addition, support shoe 98 is spaced, in the area of center section 100, at a distance from support side 96 or the side of recess 94 pointing inward in radial direction 10, as this is indicated by means of depression 108 in the side of center section 100 facing support side 96. Consequently, support shoe 98 is substantially supported via first section 102, if

necessary also via a partial section of center section 100, and second section 104, if necessary also via a partial section of center section 100, on the respective support side 96, while the support of center section 100 of support shoe 98 is carried out substantially via roller unit 74 and support track 70, 72. By this means, a support at three support points spaced apart from each other is correspondingly carried out, which has been proven to be advantageous . Figure 5 schematically shows a drivetrain 110 for a motor vehicle, wherein the different possibilities for arranging rotational vibration damper 2 according to Figures 1 through 4 are indicated. Drivetrain 110 has a drive unit 112, a torsional vibration damper 114 which may be designated as a dual mass fly wheel and which follows drive unit 112 in the torque flow, a clutch device 116 following torsional vibration damper 114 in the torque flow, and a transmission 118 following clutch device 116 in the torque flow. Thus, rotational vibration damper 2 - as indicated in Figure 5 respectively by dashed lines - may be mounted with the base part 18 thereof rotationally fixed on the input side 120 of torsional vibration damper 114, on the output side 122 of torsional vibration damper 114, on the input side 124 of clutch device 116, on the output side 126 of clutch device 116, on the input side 128 of transmission 118, and/or on the output side 130 of transmission 118.

Multiple rotational vibration dampers 2 of the previously described type may also be used within drivetrain 110 at the previously listed points within drivetrain 110. The clutch device 116 is preferably a multiple disk clutch device, wherein base part 18 of rotational vibration damper 2 is mounted rotationally fixed on an input side or output side disk carrier or on a radial support section of an input side or output side disc carrier, particularly as by this means a joint stiffening of rotational vibration damper 2 and the disk carrier or support section of the disk carrier may be carried out. List of references

2 Rotational vibration damper

4 Axial direction

6 Axial direction

8 Radial direction

10 Radial direction

12 Circumferential direction

14 Circumferential direction

16 Axis of rotation

18 Base part

20 Inertial mass part

22 Roller

24 Roller axis

26 Roller track

28 Outer side

30 Peripheral circle

32 Peripheral groove

34 Groove

36 Reset device

38 Spring unit

40 Lever element

42 Set force engagement point

44 Reset force engagement point

46 Pivot point

48 Displacement path

50 Guide

52 First lever section

54 Second lever section

56 Guide

58 Lever part

60 Lever mass part 62 Center of mass

64 Center of mass

66 Center of mass

68 Line/Radial

70 Support track

72 Support track

74 Roller device

76 Inner race

78 Rolling elements

80 Outer race

82 Guide

84 Part

86 Helical spring

88 Helical spring

90 Support point

92 Support point

94 Recess

96 Support side

98 Support shoe

100 Center section

102 First section

104 Second section

106 Clearance

108 Indentation

110 Drivetrain

112 Drive unit

114 Torsional vibration damper

116 Clutch device

118 Transmission

120 Input side

122 Output side

124 Input side 126 Output side

128 Input side

130 Output side li Length

1₂ Length

ri Largest radius

T2 Radius of the peripheral circle

Claims

A rotational vibration damper (2) comprising a base part (18) rotatable around an axis of rotation (16) and an inertial mass part (20) which is rotatable relative to the base part (18) and counter to the reset force of a reset device (36) , wherein the reset device (36) has a spring unit (38) for

generating a set force, characterized in that the reset device (36) has at least one lever element

(40) pivotable around a pivot point (46), via which lever element the set force is transmittable from a set force engagement point (42) of the lever element

(40) to the inertial mass part (20) while generating the reset force affecting the inertial mass part

(20) via a reset force engagement point (44) of the lever element (40) .

The rotational mass damper (2) according to Claim 1, characterized in that the lever element (40) is supported or is supported on the base part (18) via a support track (70; 72) on the base part (18) or on the lever element (40) on the one side and [via] a rotatable roller unit (74) rollable along the support track (70; 72) on the lever element (40) or the base part (18), wherein the set force engagement point (42) is preferably moveable along the support track (70; 72) by rotating the inertial mass part (20) relative to the base part (18) and the roller unit (74) is particularly preferably formed as a roller bearing, if necessary as a needle bearing.

The rotational vibration damper (2) according to one of the preceding claims, characterized in that the spring unit (38) has at least one helical spring (86; 88) for generating the set force, which helical spring is arranged in a recess (94) on the base part (18), wherein preferably at least one displaceable support shoe (98) is arranged in the recess (94) on the helical spring (86; 88), via which support shoe the helical spring (86, 88) is supported or is supportable outward in radial direction (8) on a support side (96) of the recess (94) facing one of the helical springs (86; 88), and the support shoe (98) particularly preferably extends between the outer periphery of the helical spring (86, 88) and the support side (96), if necessary while creating a clearance (106) between the support side (96) and the outer periphery of the helical spring (86; 88) in an area of the helical spring (86, 88) between the support shoe (98) on the one side and a further support shoe or a support point (90, 92) of the helical spring (86; 88) on the base part (18) on the other side. 4. The rotational vibration damper (2) according to

Claim 3, characterized in that the set force of the spring unit (38) is transmittable via the support shoe (98) to the set force engagement point (42), and/or the support shoe (98) is supported or is supportable on the base part (18), if necessary in the area of the set force engagement point (42), together with the lever element (40) via the roller unit (74) and the support track (70; 72) .

The rotational vibration damper (2) according to one of Claims 3 or 4, characterized in that the spring unit (38) has two helical springs (86, 88) which function counter to each other on the lever element (40), wherein the support shoe (98) preferably forms the support shoe for the one helical spring (86) as well as the support shoe for the other helical spring (88) and is particularly preferably formed as one piece, if necessary from plastic.

The rotational vibration damper (2) according to one of the preceding claims, characterized in that the center of mass (66) of the lever element (40) is arranged on a level with the set force engagement point (44) in radial direction (8), further outward than the set force engagement point (44) in radial direction (8) or further outward than the pivot point (46) in radial direction (8), preferably at least at a level with the reset force engagement point (44) in radial direction (8, 10), particularly preferably further outward than the reset force engagement point (44) in radial direction (8), wherein the center of mass (66) of the lever element

(40) is arranged on a common line (68) or radial with the pivot point (46) and/or the reset force engagement point (44) and/or the set force

engagement point (42) when viewed in axial direction

(4, 6).

The rotational vibration damper (2) according to one of the preceding claims, characterized in that the lever element (40) has a lever part (58) and a lever mass part (60) which is fixed on the lever part

(58), during the arrangement of the center of mass

(66) of the lever arrangement (40), further outward in radial direction (8) than a center of mass (62) of the lever part (58), wherein the lever mass part

(60) is preferably formed intrinsically with or separately from the lever part (58), and the lever mass part (60) formed separately from the lever part

(58) is fixed detachably or non-detachably on the lever part (58) particularly preferably via a fastening point.

The rotational vibration damper (2) according to one of the preceding claims, characterized in that the inertial mass part (20) is supported or is

supportable on the base part (18) via at least three rollers (22) in radial direction (8, 10), wherein the rollers (22) are rotatably fixed preferably on the one side on the inertial mass part (20) or the base part (18) and on the other side are rollable on the base part (18) or the inertial mass part (20), and are particularly preferably rollable on a roller track (26) on the base part (18) or the inertial mass part (20), which roller track is arranged in radial direction (8) outside of a peripheral circle

(30), the radius (r₂) of which is 80%, if necessary 90% of the largest radius (ri) of the base part

(18), and which roller track is provided if

necessary on the largest radius (ri) of base part

(18) .

The rotational vibration damper (2) according to Claim 8, characterized in that the inertial mass part (20) is further supported or is further

supportable in at least one axial direction (4; 6), preferably in both axial directions (4, 6), via at least one roller (22), wherein a peripheral groove (32) is preferably provided on the outer side (28) in at least one of the rollers (22) fixed on the inertial mass part (20) or base part (18) into which groove the base part (18) or inertial mass part (20) extends, or a groove (34) is provided in the base part (18) or inertial mass part (20) into which groove the roller (22) extends.

The rotational vibration damper (2) according to one of the preceding claims, characterized in that the lever element (40) has a first lever section (52) between the set force engagement point (42) and the pivot point (46) and a second lever section (54) between the pivot point (46) and the reset force engagement point (44), the length (li, 1₂) of which is changeable by rotating the inertial mass part (20) relative to the base part (18) while

substantially maintaining the lever ratio (li / 1₂) .

The rotational vibration damper (2) according to Claim 10, characterized in that the pivot point (46) and the reset force engagement point (44) are moveable relative to the lever element (40) by changing the lengths (li, 1₂) of the lever sections (52, 54), while the set force engagement point (42) retains the relative arrangement thereof with respect to the lever element (40) .

The rotational vibration damper (2) according to Claim 10, characterized in that the pivot point (46) and the set force engagement point (42) are moveable relative to the lever element (40) by changing the lengths (li, 1₂) of the lever sections (52, 54), while the reset force engagement point (44) retains the relative arrangement thereof with respect to the lever element (40) .

The rotational vibration damper (2) according to one of the preceding claims, characterized in that the reset device (36) is adjustable by changing a reset force characteristic curve of the reset force, preferably the lever ratio (li / 1₂) of the lever element (40) is changeable, particularly preferably the pivot point (46) is adjustable by changing the lever ratio (li / I2) of lever element (40), wherein the center of mass (66) of the lever element (40) is arranged, if necessary at least in a set position of the pivot point (46), or further outward in radial direction (8) than pivot point (46) regardless of the set position of the pivot point (46) .

A drivetrain (110) for a motor vehicle with a rotational mass damper (2) according to one of the preceding claims, the base part (18) of which is mounted rotationally fixed on a component of the drivetrain (110), wherein the component is

preferably the input side (120) of a torsional vibration damper (114) or dual mass flywheel, the output side (122) of a torsional vibration damper

(114) or dual mass flywheel, the input side (124) of a clutch device (116), if necessary an input side disk carrier or a radial support section of an input side disk carrier, the output side (126) of a clutch device (116), the input side (128) of a transmission

(118), and/or the output side (130) of a

transmission (118).

15. The drivetrain (110) according to Claim 14,

characterized in that the output side (126) of the clutch device (116) is an output-side disk carrier or a radial support section of an output-side disk carrier, on which the base part (18) is mounted rotationally fixed while increasing the engine speed strength of the output-side disk carrier or the radial support section of the output-side disk carrier .