EP3215757A1

EP3215757A1 - Rotational vibration damper

Info

Publication number: EP3215757A1
Application number: EP15857902.9A
Authority: EP
Inventors: Jochen Boelling
Original assignee: BorgWarner Inc
Current assignee: BorgWarner Inc
Priority date: 2014-11-08
Filing date: 2015-11-05
Publication date: 2017-09-13
Also published as: CN107110282B; DE102014016569A1; WO2016073696A1; CN107110282A; EP3215757A4

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) counter to the reset force (70) of a reset device (26), wherein the reset device (26) has a spring unit (28) for generating a set force (68) and a lever element (30) arranged on the base part (18) and pivotable around a pivot point (34), via which lever element the set force (68) is transmittable while generating the reset force (70) affecting the inertial mass part (20). The inertial mass part (20) is supported or is supportable on the base part (18) in the radial direction (8, 10) by the lever element (30).

Description

ROTATIONAL VIBRATION DAMPER

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 and a lever element arranged on the base part pivotable around a pivot point, via which lever element the set force can be transmitted by generating the reset force affecting the inertial mass part. 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 thus 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.

A further rotational vibration damper is known from DE 10 2014 001 043 Al which partially overcomes the disadvantages of the previously described rotational vibration damper. Thus, the reset device thereof likewise has a spring unit for generating the set force; however, the reset device has in addition a lever element arranged on the base part pivotable around a pivot point, via which lever element the set force of the spring unit is transmitted while generating the reset force affecting the inertial mass part. 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 elsewhere 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, in particular further inward in the radial direction. In addition, the support of the inertial mass part in the radial direction on the base part is not carried out on the side of the base part pointing outward in the radial direction, as is the case for the rotational vibration damper according to DE 199 07 216 CI. Instead, a support part is provided on the inertial mass part rotationally fixed to the inertial mass part, which support part extends, starting from the inertial mass part, inwardly in the radial direction in order to be supported in the area of a diameter of the base part which diameter is smaller than the largest outer diameter of the base part. In this way, lower wear forces occur during rotation of the inertial mass part relative to the base part, wherein in addition the support in the area of the smaller diameter simplifies the production of the rotational vibration damper. A relatively small radial bearing may also be used on this relatively small diameter, in the area of which the support is carried out indirectly via the support part.

Starting from this prior art, the underlying object of the present invention is to create a rotational vibration damper of the generic type, in which the support of the inertial mass part is further simplified or improved in the radial direction and which has a simple and compact structure.

This problem is solved by the features listed in Claim 1. 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, which base part, for example, may be

rotationally fixed on an output side of a driven shaft, wherein the base part in this case is preferably

connected rotatably fixed to the output side of a driven shaft in the area of the axis of rotation. Basically, the base part may be fixed rotationally fixed on any rotating component of a drivetrain, which is subjected to

rotational vibrations, in order to damp or to reduce these rotational vibrations. The base part may for example be formed from a base plate or support plate extending substantially in the radial direction. The rotational vibration damper additionally has an inertial mass part. The inertial mass part is rotatable around the axis of rotation counter to the reset force of a reset device relative to the base part. The reset device has a spring unit for generating a set force, wherein the spring unit may have, for example, one spring element 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 pivotable around an axis extending through the pivot point in the axial directions of the rotational vibration damper. The lever element is arranged between the spring unit on the one hand and the inertial mass part on the other hand in such a way that the set force generated by the spring unit may be transmitted to the inertial mass part while generating the reset force affecting the inertial mass part. This initially 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 elsewhere on the base part of the rotational vibration damper, for example inwardly in the radial direction, by which means a space-saving and flexible arrangement of the spring unit on the rotational

vibration damper or on the base part of the rotational vibration damper is possible, in particular further inward in the radial direction. The inertial mass part in the rotational vibration damper according to the

invention is supported or is supportable on the base part in the radial direction via the lever element.

Consequently, the lever element has a double function, namely on the one hand the transmission of the set force of the spring unit while generating the reset force affecting the inertial mass part, and on the other hand the radial support or radial mounting of the inertial mass part. This has the advantage that the support part on the inertial mass part, known from DE 10 2014 001 019 Al and which has an especially large extension in the radial direction, may be omitted, or that merely a support part with a space-saving, smaller dimension may be provided on the inertial mass part, especially as the lever element is arranged relatively close to the

inertial mass part. A support part of this type might also be formed simply by a short protruding projection on the inertial mass part which additionally might by formed integrally with the inertial mass part. Consequently, a rotational vibration damper is created by the invention which on the one hand enables a space-saving and flexible arrangement of the spring unit and on the other hand, due to the double function of the lever element, has an especially compact and simple structure, which is additionally suited to reduce the weight of the

rotational vibration damper.

In a preferred embodiment of the rotational vibration damper according to the invention, a support part is provided on the inertial mass part, via which support part the inertial damper is supported or is supportable at a reset force engagement point on the lever element. As already previously mentioned, this support part may be dimensioned relatively small in order to achieve a compact and simple structure of the

rotational vibration damper, especially as the inertial mass part is arranged relatively close to the lever element during an actuation via the lever element. Thus, the support part may be formed intrinsically with the inertial mass part and/or be a section of the inertial mass part. The support part may, however, just as likely be a support part initially formed separately from the inertial mass part and which is then subsequently fixed to the inertial mass part. Regardless of the type of application of the support part on the inertial mass part, it is preferred in to this embodiment if the support part forms a protruding projection on the

inertial mass part in order to achieve a well-defined, predictable reset force engagement point on the lever element .

In a further preferred embodiment of the rotational vibration damper according to the invention, the support part may be moved by rotation of the inertial mass part relative to the base part while changing the reset force engagement point along the lever element.

Correspondingly, a movement of the reset force engagement point, on which the support part is supported or is supportable on the lever element, is carried out by this means along the lever element.

In order to significantly reduce the wear between the support part and the lever element, along which the support part is moveable relative to the base part due to rotation of the inertial mass part, the support part is formed, in a particularly preferred embodiment of the rotational vibration damper according to the invention, by a roller which is rollable on the lever element during the listed movement. Thus, the support part in this embodiment may be formed in

particular by a roller rotatably fixed on the inertial mass part, wherein the roller may also be designated as a wheel .

In an advantageous embodiment of the rotational vibration damper according to the invention, the lever element has two lever sections, wherein the support part is supported or is supportable on the one lever section due to rotation of the inertial mass part from a starting rotational position in the one circumferential direction relative to the base part and is supported or is

supportable on the other lever section due to rotation of the inertial mass from a starting rotational position in the opposite circumferential direction relative to the base part. In a further advantageous embodiment of the rotational vibration damper according to the invention, the lever element is arranged in a starting pivot

position in the starting rotational position of the inertial mass part. In this case, it is preferred if the lever element is retained in the starting pivot position by the spring unit. The spring unit may thereby be detensioned for example in the starting pivot position of the lever element. Alternatively or supplementally, the lever element is pretensioned in the starting pivot position by the spring unit. In this embodiment, it is further preferred if the lever element extends in the starting pivot position thereof transversely to a radial through the reset force engagement point. Thus, the lever element may, for example, extend at a right angle to the radial through the reset force engagement point. Basically, the previously mentioned two lever sections of the lever element may be arranged on the same side of the pivot point, wherein the pivot point may be provided for example on the end side on the lever

element. However, in order to achieve a particularly secure support of the inertial mass part via the lever element and thus also via the pivot point, the two lever sections are arranged on diametrically opposite sides of the pivot point in a particularly advantageous embodiment of the rotational vibration damper according to the invention. This ensures that the reset force engagement point is always arranged relatively close to the pivot point in relation to the circumferential direction regardless of the respective rotational position of the inertial mass part relative to the base part, in order to achieve a secure support of the inertial mass part via the lever element and the pivot point. It is also

preferred in this embodiment if the lever element is formed symmetrically or mirror-symmetrically with respect to the pivot point.

In a further especially advantageous embodiment of the rotational vibration damper according to the invention, in which the two lever sections are arranged on diametrically opposite sides of the pivot point, the pivot point and the reset force engagement point are arranged on a common radial in the starting pivot

position of the lever element. It might also be stated in this case that the pivot point and the reset force engagement point are arranged in alignment with each other in a radial direction or along a radial in the starting pivot position of the lever element. By this means, a particularly secure support of the inertial mass part on the base part is achieved via the lever element and the pivot point if the inertial mass part is located in the starting rotational position thereof relative to the base part.

In a further especially advantageous embodiment of the rotational vibration damper according to the invention, a support track is provided on the lever element, along which support track the support part is movable during rotation of the inertial mass part

relative to the base part. Thus, the support track may be assembled for example from a support track section on the one lever section and a support track section on the other lever section, wherein the course of the two support track sections may be formed symmetrical or mirror-symmetrical relative to the transition region between the two support track sections. In this

embodiment it is also possible to form the support track as a straight line or as having a straight shape.

However, in order to change or adapt the reset force characteristic curve of the reset device in a targeted way, the support track preferably has a course deviating from a straight-line course. With regard to the course of the support track deviating from a straight-line course, this may be for example a constant or irregular course. In this case, it is particularly preferred if the support track has an arc-shaped course. The arc-shaped course may thereby be configured as constant or irregular. Thus, for example, a bent, curved, and/or domed course is possible. In this context, a circular arc shape for example has proven to be advantageous. In order to affect a targeted return of the lever element into the starting pivot position thereof via the support track and the spring unit, if the inertial mass part is located in the

starting rotational position thereof, it is moreover preferred in this embodiment if the support part is accommodated or is accommodatable in a trough-like or bowl-like way by the support track. A trough- or bowl- shaped support track may be discussed in this case, in which the support part is accommodated or is

accommodatable . In order to additionally support the inertial mass part on the base part in a space-saving way that simplifies the structure, even in the axial direction, the inertial mass part is additionally supported or is supported on the base part via the lever element in at least one axial direction, if necessary in both axial directions, in a further preferred embodiment of the rotational vibration damper according to the invention. Consequently, the lever element in this embodiment has a three-fold function, namely the transmission of the set force of the spring unit while generating the reset force affecting the inertial mass part, the support of the inertial mass part on the base part in the radial

direction, and the support of the inertial mass part on the base part in at least one of the axial directions. Basically, in this embodiment, additional support parts or support elements might be provided on the inertial mass part and/or on the lever element in order to affect the corresponding support in at least one of the axial directions, if necessary in both axial directions.

However, in order to simplify the structure of the rotational vibration damper in a space-saving way, the previously mentioned support part, via which the inertial mass part is supported or is supportable at a reset force engagement point on the lever element, is arranged or formed relative to the lever element in such a way that the support part is supported or is supportable on the lever element in at least one of the axial directions, if necessary in both axial directions, in order to support the inertial mass part in at least one of the axial directions, if necessary in both axial directions, on the base part via the lever element. As previously mentioned, the support part may be a roller which is rollable on the lever element in order to reduce the wear between the support part and the lever element. In a further preferred embodiment of the rotational vibration damper according to the invention, this roller extends into a groove in the lever element or the roller itself has a groove in the outer side thereof, into which groove the lever element extends in order to support the inertial mass part via the support part formed as a roller in at least one axial direction, preferably in both axial directions, on the base part via the lever element.

In order to have a greater flexibility with respect to the arrangement of the spring unit and also with respect to the selection of the spring element for the spring unit, at least one force transmission element is provided in a further preferred embodiment of the rotational vibration damper according to the invention by means of which the set force of the spring unit is transmittable from the spring unit to a set force

engagement point on the lever element. The force

transmission element is preferably a force transmission lever, thus correspondingly a further lever element, wherein the force transmission lever is preferably formed to be rigid and/or bend-proof. Thus, the force

transmission lever may be articulated and/or supported for example on the one side on the spring unit and on the other side on the set force engagement point. It is also preferred if a deflection of the set force generated by the spring unit or the respective spring element of the spring unit is carried out by the force transmission element or the force transmission level. Basically, the spring unit may have any shape of a spring element, thus for example a tension spring, a compression spring, or a tension and compression spring, such as for example a helical spring. However, other spring elements, which are able to generate a spring force forming the set force, are also possible. In a further preferred embodiment of the rotational vibration damper according to the invention, the spring unit has at least one flexible spring or leaf spring, particularly as a flexible- or leaf spring may be provided on the

rotational vibration damper in a particularly space- saving way. It is hereby preferred, if the flexible spring or leaf spring extends along a radial, in order to minimize the influence of high centrifugal forces

affecting the flexible spring at high rotational speeds of the rotational vibration damper. In order to amplify this advantage, it is further preferred in this

embodiment if a spring section of the flexible spring or leaf spring is arranged inwardly in a radial direction. Correspondingly, the effective length of the flexible spring or leaf spring is hereby formed by a spring section arranged outwardly in the radial direction.

Basically, the reset force characteristic curve of the reset force affecting the inertial mass part might be equally formed. However, in order to be able to react usefully in a suitable way to different operating states within the drivetrain or the rotational vibration damper, for example to different rotational speeds of the base part of the rotational vibration damper, the reset force characteristic curve of the reset force affecting the inertial mass part is changeable in a further

particularly advantageous embodiment of the rotational vibration damper according to the invention. In this embodiment, it is preferred if the set force

characteristic curve of the set force exerted by the spring unit on the lever element is changeable while changing the reset force characteristic curve. If the spring unit - as previously indicated - should have at least one flexible spring or leaf spring, then it is further preferred if the set force characteristic curve of the at least one spring unit having a flexible spring or leaf spring may be changed by changing the effective length of the flexible spring or leaf spring, if

necessary by changing the clamping length of the flexible spring or leaf spring.

In a further advantageous embodiment of the rotational vibration damper according to the invention, the inertial mass part is rotatable relative to the base part while maintaining a predetermined radial distance to the axis of rotation. Consequently, in this embodiment, vibrations or movements of the inertial mass part in the radial direction may be prevented so that a compensation of these types of vibrations or movements of the inertial mass part in the radial direction may be disregarded during the design, which leads to a simplified structure of the rotational vibration damper.

In a further preferred embodiment of the rotational vibration damper according to the invention, the inertial mass part is formed with an annular shape or annular disk shape. In this way, only one inertial mass part must be provided, wherein, due to the annular configuration, imbalances are prevented and a targeted balancing is largely unnecessary.

In a further preferred embodiment of the rotational vibration damper according to the invention, the lever element is formed to be bend-proof and/or rigid. In a further preferred embodiment of the rotational vibration damper according to the invention, the inertial mass part is supported or is supportable on the base part exclusively via the lever element in the radial and/or axial direction. In other words, in this embodiment, no additional support of the inertial mass on the base part is carried out which is not carried out by the lever element. However, this also includes

embodiments in which the inertial mass part is

additionally or supplementally supported or is

supportable in the radial and/or axial direction on another component of a drivetrain.

In a further particularly preferred embodiment of the rotational vibration damper according to the invention, the inertial mass part is supported or is supportable exclusively via the lever element in the radial and/or axial direction. In other words, the support of the inertial mass part in the radial and/or axial direction in this embodiment, apart from the lever element on the base part, is not carried out via another component of the drivetrain.

In order to guarantee a secure reset of the inertial mass part by the reset force, at least two or three reset devices are provided in a further preferred embodiment of the rotational vibration damper according to the invention. In order to achieve the important symmetry of the rotational vibration damper during a rotational movement, the at least two or three reset devices are preferably arranged in the circumferential direction at a uniform distance from each other.

In order to broadly synchronize the lever elements of the at least two or three reset devices, the pivot movements of the lever elements are coupled to each other in a further particularly preferred embodiment of the rotational vibration damper according to the

invention, wherein the coupling is preferably carried out in a mechanical way. In this embodiment, it is further preferred if the coupling of the pivot movements of the lever elements does not exclusively result from the interplay between the inertial mass part and the

respective lever element, instead, additional coupling elements should be provided. It is thus particularly preferred in this case if the pivot movement of the lever elements of at least two reset devices or all of the reset devices are coupled to each other via the reset devices themselves such that the reset devices or

individual components of the reset devices sensibly form the previously mentioned coupling elements.

In a further particularly advantageous embodiment of the rotational vibration damper according to the invention having at least two or three reset devices, a component of the one reset device equally forms a component of at least one further reset device. This may relate for example to the previously mentioned force transmission element, which may be formed for example as a force transmission lever. In this

embodiment, it is particularly preferred if a spring unit or at least a spring element of a spring unit of the reset device equally forms the spring unit or a spring element of a spring unit of at least one further reset device. In this way, the rotational vibration damper or the structure thereof may be significantly simplified. Correspondingly, in this embodiment a spring unit or a spring element of a spring unit is assigned to at least two reset devices. The invention will subsequently be explained in more detail by means of embodiments with reference to the accompanying drawings. As shown in:

Figure 1 a front view of a first embodiment of the rotational vibration damper according to the invention with the inertial mass part in an output rotational position,

Figure 2 the rotational vibration damper from

Figure 1 with the inertial mass part rotated out of a starting rotational position in a first circumferential direction relative to the base part,

Figure 3 the rotational vibration damper from

Figure 1 with the inertial mass part rotated out of a starting rotational position in a second circumferential direction relative to the base part,

Figure 4 a front view of a second embodiment of the rotational vibration damper according to the invention,

Figure 5 a front view of a third embodiment of the rotational vibration damper according to the invention,

Figure 6 a front view of a fourth embodiment of the rotational vibration damper according to the invention, Figure 7 a front view of a fifth embodiment of the rotational vibration damper according to the invention,

Figure 8 a front view of a sixth embodiment of the rotational vibration damper according to the invention,

Figure 9 a partial side view in the area of the support part and the lever element from Figures 1 through 8 in a first embodiment of the support part and the lever element, and

Figure 10a partial side view in the area of the support part and the lever element from Figures 1 through 8 in a second embodiment of the support part and the lever element.

Figures 1 through 3 show a first 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 8 [sic: 2] are indicated by corresponding arrows, wherein rotational vibration damper 2 has an axis of rotation 16 extending in the axial directions 4, 6. Subsequently, the two circumferential directions 12, 14 will also be designated as first circumferential direction 12 and second circumferential direction 14.

Rotational vibration damper 2 has a base part 18 rotatable around the axis of rotation 16 in

circumferential directions 12, 14. Base part 18 may be formed for example as 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, if necessary in the area of axis of rotation 16, be directly or indirectly connected rotationally fixed to each component of a drivetrain which is

subjected to rotational or torsional vibrations. Thus, base part 18 may be connected rotationally fixed to the output shaft of an internal combustion engine, a flywheel mass, or to the input or output side of a torsional vibration damper.

Rotational vibration damper 2 additionally has an inertial mass part 20. Inertial mass part 20 is formed with an annular shape or an annular disk shape and extends in circumferential directions 12, 14. Annular shaped or annular disk shaped inertial mass part 20 is thereby formed as continuous or closed in circumferential direction 12, 14. Inertial mass 20 in the embodiment shown is also spaced apart from base part 18 such that no wear contact exists between inertial mass part 20 on the one hand and base part 18 on the other hand. Thus, in particular a radial distance ri is provided between the outer side 22 of base part 18 facing inertial mass part 20 pointing outward in radial direction 8 and the inner side 24 of inertial mass 20 facing base part 18 and pointing inward in radial direction 10.

Inertial mass part 20 may be rotated relative to base part 18 around axis of rotation 16 counter to the reset force of a reset device 26. Thus, inertial mass 20 may be rotated in first circumferential direction 12, as is shown in Figure 2, and also in opposing second

circumferential direction 14, as this is shown in Figure 3, around axis of rotation 16 relative to base part 18 counter to the reset force of a reset device 26. Inertial mass part 20 is thereby rotatable while respectively maintaining radial distance ri between inertial mass part 20 and base part 18 and also while maintaining a

predetermined radial distance r₂ to axis of rotation 16 relative to base part 18.

As is evident from Figures 1 through 3, rotational vibration damper 2 in the embodiment shown has two reset devices 26 which are arranged diametrically opposite each other on rotational vibration damper 2, in this case on base part 18 of rotational vibration damper 2, and are designed substantially identical in

construction such that the reset device 26 is

subsequently described with reference to only one of the reset devices 26, wherein the description equally applies for the other reset device 26. It should also be noted that rotational vibration damper 2 preferably has two or three reset devices 26, wherein reset devices 26 should preferably be arranged in circumferential direction 12, 14 at a uniform distance from each other on rotational vibration damper 2 or base part 18 thereof, as this is already clear from Figures 1 through 3, in which two reset devices 26 are at a uniform distance from each other in circumferential direction 12, 14. Reset device 26 has a spring unit 28 for generating a set force and a lever element 30 arranged pivotably on base part 18, which lever element may also be designated as a rocker element or rocker, via which the set force of spring unit 28 may be transmitted to inertial mass part 20 while generating the reset force affecting inertial mass part 20, wherein the set force of spring unit 28 is transmittable via at least one force transmission element 32, which is here formed as a force transmission lever, from spring unit 28 to lever element 30. Lever element 30 shall be discussed subsequently in more detail . Lever element 30 is pivotable relative to base part 18 around a fixed pivot point 34. Consequently, lever element 30 may be pivoted relative to base part 18 at pivot point 34 around a pivot axis extending in axial directions 4, 6, wherein pivot point 34 is spaced at a distance from axis of rotation 16 of rotational vibration damper 2 in radial direction 8, as this is indicated by radial distance r₃. As pivot point 34 is arranged fixedly on base part 18, radial distance r₃ is unchangeable.

Lever element 30 is formed as rigid or bend-proof and has two lever sections 36, 38, namely a first lever section 36 and a second lever section 38. Whereas first lever section 36, starting from pivot point 34, extends to the one side of pivot point 34, second lever section 38, starting from pivot point 34, extends to the other side of pivot point 34. It may thus be stated that the two lever sections 36, 38 are arranged at diametrically opposite sides of pivot point 34. As is evident from the figures, the two lever sections 36, 38 are moreover formed symmetrically or mirror-symmetrically with respect to pivot point 34.

A support track 40 is provided, extending along lever element 30, on a side of lever element 30 pointing outward in radial direction 8 or inward in radial direction 10; in the embodiment shown, it is on the side pointing outward in radial direction 8. Support track 40 extends across first lever section 36 and also across second lever section 38, wherein support track 40 has a course deviating from a straight-line course. Thus, support track 40 has an arch-shaped course, more exactly a circular arc shaped course in the embodiment shown. In the starting rotational position of inertial mass 20 or the starting pivot position of lever element 30 shown in Figure 1, support track 40 is arranged in the area of pivot point 34 closest to axis of rotation 16,

particularly as support track 40 is also formed

symmetrically with respect to pivot point 34 and is curved outward in a center section in the direction of axis of rotation 16. It may also be stated that support track 40 is formed as a trough or bowl shape and that a corresponding trough- or bowl-shaped indentation is provided in the side of lever element 30. Even though a continuous course of support track 40 is shown in the figures, it is likewise possible to provide a support track 40 with a discontinuous course. It is moreover possible to achieve the arch-shaped course of support track 40 through multiple straight-line support track sections, which transition at angles or curves into each other.

Force transmission element 32 in the form of the force transmission lever is supported and pivoted on an end section of first lever section 36 facing away from pivot point 34, wherein force transmission element 32 extends, starting from this articulation point 42, in a plane spanned by radial directions 8, 10 up to an

articulation point 44, on which force transmission element 32 is supported and pivoted on a spring element 46 of spring unit 28. Force transmission element 32 formed as a force transmission lever is - as already stated regarding lever element 30 - formed as bend-proof or rigid force transmission element 32. As previously mentioned, spring unit 28 has a spring element 46. Spring element 46 is formed by a flexible spring or leaf spring 48 in the embodiment shown. In addition, spring unit 28 has a clamp 50 for flexible- or leaf spring 48, via which clamp flexible- or leaf spring 48 is supported and clamped on base part 18. As is evident from the figures, spring element 46 formed as flexible- or leaf spring 48 extends along a radial 52, if inertial mass part 20 is located in the starting rotational position thereof according to Figure 1 or if lever element 30 is located in the starting pivot

position thereof according to Figure 1. Thus, in the embodiment shown, a spring section 54 arranged inwardly in radial direction 10 is clamped by clamp 50.

Consequently, spring element 46 in the form of flexible- or leaf spring 48 has a clamping length a, at which an effective length b connects outwardly in radial direction 8, which effective length b is formed between the

beginning of clamp 50 and articulation point 44, at which force transmission element 32, in the form of the force transmission lever, is supported and articulated.

Inertial mass part 20 is supported or is supportable, correspondingly mounted, on base part 18 via lever element 30 in radial direction 10, and also in radial direction 8 due to the additional reset device. For this purpose, a support part 56 is provided on inertial mass part 20, via which support part inertial mass part 20 is supported or is supportable on a reset force engagement point 58 on lever element 30. In the embodiment shown, support part 56 is formed by a roller 60 which is rotatably fixed on inertial mass part 20 around a roller axis 62 extending in axial directions 4, 6, wherein the rotatable fixing of roller 60 on inertial mass 20 in the embodiment shown is carried out via a roller bracket 64 provided on inertial mass part 20.

Basically, a roller bracket 64 could, however, be

eliminated, instead roller axis 62 of roller 60 might also be arranged directly on inertial mass part 20, for example on a side of inertial mass part 20 pointing in axial directions 4, 6. Support part 56 formed as roller 60 is also supported or is supportable on reset force engagement point 58 on previously described support track 40 of lever element 30 such that support part 56 in the form of roller 60 is accommodated in a trough- or bowllike way by support track 40. It may also be stated regarding this that support part 56 immerses or is immersed in the indentation in the side of lever element 30.

Subsequently, the functionality of rotational vibration damper 2 will be explained in more detail with reference to Figures 1 through 3, wherein it should be noted that articulation point 42 equally forms a set force engagement point 66 at which the set force of spring unit 28 engages at lever element 30 via force transmission element 32.

If inertial mass part 20 which is connected rotationally fixed to base part 18 is rotated, due to rotational vibrations of a component within the

drivetrain, from its starting rotational position in Figure 1 relative to base part 18 in first

circumferential direction 12, as this is shown in Figure 2, then support part 56 likewise moves in first

circumferential direction 12 relative to base part 18, such that support part 56 is moved along lever element 30 while changing reset force engagement point 58. Stated more exactly, by this means, support part 56 is moved along support track 40 of lever element 30, wherein support part 56 is supported or is supportable on the support track section of first lever section 36. As support part 56 is formed as rotatable roller 60, support part 56 rolls on support track 40 of lever element 30 such that only low wear forces are created in the area of reset force engagement point 58. As a result of the rotation of inertial mass part 20 from the starting rotational position, lever element 30 is also pivoted from the starting pivot position thereof, according to Figure 1, into the pivot position according to Figure 2. This results in that spring element 46 of spring unit 28 is tensioned or more strongly tensioned via force

transmission element 32, which is achieved in the

embodiment shown by a flexing of flexible- or leaf spring 48. Consequently, spring unit 28 exerts a set force 68 on set force engagement point 66 of lever element 30 via force transmission element 32, which set force may be transmitted by lever element 30 and support part 56 interacting therewith to inertial mass part 20 while generating a reset force 70 acting in second

circumferential direction 14 in the area of reset force engagement point 58. If, in contrast, inertial mass part 20 is rotated, due to rotational vibrations, relative to base part 18 in opposing second circumferential direction 14, as this is shown in Figure 2, then support part 56 is also rotated relative to base part 18 in circumferential direction 14 such that support part 56 in turn is moved along lever element 30 or support track 40 of lever element 30 while changing reset force engagement point 58, wherein support part 56 in the form of roller 60 again rolls on lever element 30 or support track 40. In this case, however, support part 56 is supported by that section of support track 40 which is provided on second lever section 38. In general, the previous statements correspondingly apply, wherein it should be noted that spring element 46 in the form of flexible- or leaf spring 48 is tensioned or articulated in the opposite direction such that set force 68 and reset force 70 also function in the opposite direction.

As previously indicated, lever element 30 is arranged in a starting pivot position if inertial mass part 20 is located in the starting rotational position relative to base part 18 as shown in Figure 1. In the starting pivot position of lever element 30, lever element 30 extends transverse to a radial 72 through reset force engagement point 58. Thus, lever element 30 may preferably extend at a right angle to radial 72 through reset force engagement point 58. Lever element 30 is also held in the starting pivot position thereof by spring unit 28, wherein spring unit 28 is detensioned, in the embodiment shown, if lever element 30 is located in the starting pivot point thereof. It may also be stated regarding this, that lever element 30 is pretensioned by spring unit 28 in the starting pivot position,

particularly as spring unit 28 counters any pivoting of lever element 30 out of the starting pivot position with a set force 68, even if lever element 46 is not

pretensioned in the starting pivot position of lever element 30. It should additionally be noted that in the present embodiment, selected spring element 46 is a double-acting spring element 46 which counters a pivoting of lever element 30 from the starting pivot position in both pivoting directions, as this is already shown with reference to Figures 2 and 3. Double-acting spring element 46 thus has the advantage that basically no additional spring element must be used to apply a

countering set force.

In order to achieve a particularly secure support of inertial mass part 20 in radial direction 8, 10 by means of lever element 30 on base part 18, pivot point 34 and reset force engagement point 58 are

arranged, in the starting pivot position of lever element 30 shown in Figure 1, on a common radial which

corresponds to the previously mentioned radial 72. In addition, inertial mass part 20 is supported or is supportable on base part 18 in radial direction 8, 10 exclusively via lever element 30. In other words, each support force transmission path of a support force for supporting inertial mass part 20 in radial direction 8, 10 on base part 18 runs across lever element 30. Thus, a support force transmission path may run for example across roller bracket 64, roller 60, lever element 30, and pivot point 34. Another support force transmission path may extend over roller bracket 64, roller 60, lever element 30, force transmission element 32, spring element 46, and clamp 50. In the installed state within a

drivetrain, inertial mass part 20 might, however, also be supported or be supportable in radial direction 8, 10 on an adjacent component of the drivetrain; however, it is preferred if inertial mass part 20 is supported or is supportable in radial direction 8, 10 exclusively via lever element 30 such that a simplified structure and a particularly low wear may be achieved, particularly as it has been shown that the support of inertial mass part 20 in radial direction 8, 10 exclusively via lever element 30 is sufficient to guarantee a secure support and mounting.

In order to be able to adjust reset force 70 affecting inertial mass part 20 at reset force engagement point 58 to the operating states within a drivetrain, a reset force characteristic curve of reset force 70 affecting inertial mass part 20 is additionally

changeable. In the embodiment shown, a set force

characteristic curve of set force 68 exerted by spring unit 28 at set force engagement point 66 on lever element 30 may be changed for this purpose while changing the reset force characteristic curve. This may be carried out preferably by changing the effective length b of flexible spring or leaf spring 48. Effective length b of flexible- or leaf spring 48 may thereby be changed basically in two ways. On the one hand, articulation point 44 may be designed to be displaceable along flexible- or leaf spring 48 in order to increase or to reduce effective length b. On the other hand, effective length b may be changed or varied by a change of clamping length a. Thus, clamp 50 might be displaceable for example along

flexible- or leaf spring 48 relative to the same in order to vary or to change clamping length a and thus also effective length b, as this is shown in Figure 1 by means of a dashed line indicating displaced clamp 50. Figure 4 shows a second embodiment of

rotational vibration damper 2 which corresponds

substantially with the embodiment according to Figures 1 through 3, such that subsequently only the differences shall be addressed, identical reference numbers are used for identical or similar parts and the previous

description correspondingly generally applies.

In contrast to the first embodiment, in the second embodiment according to Figure 4, a further force transmission element 74 is respectively used at each of the reset devices 26, here at both reset devices 26.

Force transmission element 74 is in turn formed as a bend-proof or rigid force transmission lever. Thus, force transmission element 74 is supported and articulated on the one side at an articulation point 76 on lever element 30, wherein articulation point 76 is in turn formed as a set force engagement point 78. In contrast to

articulation point 42 or set force engagement point 66, articulation point 76 or set force engagement point 78 is provided, however, on an end section of second lever section 38 of lever element 30 facing away from pivot point 34. Starting from articulation point 76 or set force engagement point 78, force transmission element 74 extends to a further articulation point 80 on spring element 46 of the respectively other reset device 26 of the two reset devices 26. Articulation point 80 of the one reset device 26 thereby corresponds to articulation point 44 of the other reset device 26. Consequently, the pivot movements of lever element 30 of the two reset devices 26 are not only coupled to each other via

inertial mass part 20 in connection to support parts 56, instead the coupling of the pivot movement of lever element 30 is also carried out via reset devices 26 themselves. In addition, some components of the one reset device 26 equally form a component of the other reset device 26, such that in substantially identical

operation, the number of parts is reduced and the

structure is simplified. This relates in the current case in particular to spring unit 28 of the one reset device 26, which identically forms a spring unit 28 of the other reset device 26, and vice versa. In other words, spring unit 28 of the one reset device 26 is also assigned to the other reset device 26, and vice versa. The

functionality of the second embodiment according to

Figure 4 is likewise implied in Figures 2 and 3, in which the further force transmission element 74 is indicated at least be dashed lines.

Figure 5 shows a third embodiment of the rotational vibration damper 2, which substantially corresponds to the first or second embodiment according to Figures 1 through 4, such that subsequently only the differences shall be addressed, identical reference numbers are used for identical or similar parts and the previous description correspondingly generally applies.

In contrast to the previously described embodiments, spring element 46 in the form of flexible- or leaf spring 48 is clamped in the third embodiment in such a way that a spring section 82 arranged outwardly in the radial direction 8 is clamped via clamp 50 such that effective length b is provided inwardly in radial direction 10 relative to clamp 50. In general, the previous statements regarding the embodiments according to Figures 1 through 4 correspondingly apply. Figure 6 shows a fourth embodiment of

rotational vibration damper 2, which substantially corresponds to the previously described embodiments, such that subsequently only the differences shall be

addressed, identical reference numbers are used for identical or similar parts and the previous description correspondingly generally applies.

In contrast to the embodiment according to Figures 1 through 3, spring unit 28 in the fourth

embodiment of rotational vibration damper 2 has a further spring element 84. Spring elements 46, 84 are also respectively formed as compression springs, here as helical compression springs, which are supported on the side thereof facing away from the respective set force engagement point 78 via a support 86 on base part 18. Alternatively to the embodiment variant according to Figure 6, however, one of the two spring elements 46 or 84 including the associated support 86 might be dispensed with, in this case, the respective spring element 46 or 84 would be formed as tension and compression springs, preferably as helical springs, in order to generate a reset force 70 on inertial mass part 20 in both opposing circumferential directions 12, 14 via lever element 30. Figure 7 shows a fifth embodiment of rotational vibration damper 2, which substantially corresponds to the previously described embodiments, such that subsequently only the differences shall be

addressed, identical reference numbers are used for identical or similar parts and the previous description correspondingly generally applies. In the fifth embodiment as well, the

individual spring element 46 of the respective reset device 26 is formed as flexible- or leaf spring 48 with clamp 50. As already indicated in Figure 4, a further force transmission element 74 is provided. However, this does not extend to spring element 46 of the respectively other reset device 26, but instead to the other end of spring element 46 of the associated reset device 26. In this embodiment as well, the set force characteristic curve may be changed while changing the reset force characteristic curve, for example by a displacement of clamp 50, wherein spring element 46 in the form of flexible- or leaf spring 48 hereby has a center clamping length a and two outer effective lengths b. In a

modification of the embodiment according to Figure 7, a single large flexible- or leaf spring 48 might also be provided which forms both spring element 46 of the one and also of the other reset device 26, as this is

indicated in Figure 4 by the dashed line between spring elements 46.

Figure 8 shows a sixth embodiment of rotational vibration damper 2 which corresponds

description correspondingly generally applies.

In contrast to the first embodiment, pivot point 34 of lever element 30 is not provided centered on lever element 30. Pivot point 34 is instead provided on the end section of second lever section 38 facing away from first lever section 36. Consequently, pivot point 34 in the sixth embodiment is not arranged with reset force engagement point 58 on a common radial 72, if inertial mass part 20 is located in the starting rotational position thereof of if lever element 30 is located in the starting pivot position thereof according to Figure 8.

In all previously described embodiments of rotational vibration damper 2, inertial mass part 20 is further supported or is supportable on base part 18 via lever element 30 in at least one axial direction 4; 6, here in both axial directions 4, 6. It is hereby

preferred if this support is achieved in axial directions 4, 6, in that support part 56 is supported or is

supportable on lever element 30 in at least one of axial directions 4, 6, here in both axial directions 4, 6, as this shall be described by way of example according to the embodiment variant of support part 56 in Figures 9 and 10.

In the first embodiment variant of support part 56 according to Figure 9, roller 60 forming support part 56 has a peripheral groove 88 in the rolling surface on the outer side of the roller, in which groove the side of lever element 30 having support track 40 extends outwardly in radial direction 8, 10 - here outward in radial direction 8. Consequently, roller 60, which forms support part 56, is supported or is supportable on base part 18 by lever element 30 extending into groove 88 in axial direction 4 as well as in axial direction 6 via lever element 30. This first embodiment variant according to Figure 9 represents a particularly easy to manufacture embodiment variant, particularly as groove 88 may be generated relatively easily in roller 60 forming support part 56. This applies correspondingly for a support part 56 not formed as a roller 60, which may be formed for example as a simple protruding projection without a rolling function. Figure 10 shows a further embodiment variant in the area of lever element 30 and support part 56. In this embodiment variant, groove 90 is formed in the side of lever element 30 facing support part 56, wherein support part 56 - here in the form of roller 60 - extends into groove 90 in radial direction 8, 10 - here in radial direction 10 - in order to effect a support of inertial mass part 20 on base part 18 in both axial directions 4, 6 via support part 56 and via lever element 30.

As is already the case in the radial support of inertial mass 20, inertial mass 20 is exclusively supported or is supportable on base element 18 via lever element 30 in axial direction 4, 6. In other words, each set force transmission path of a set force for supporting inertial mass part 20 on base part 18 in axial direction 4, 6 runs across lever element 30. Thus, a corresponding set force transmission path might run for example across roller bracket 64, support part 56 in the form of roller 60, lever element 30, and pivot point 34 in order to affect a support in axial direction 4, 6 on base part 18. A set force transmission path of this type might also run across roller bracket 64, roller 60, lever element 30, one of set force transmission elements 32 and/or 74, and spring unit 28 in order to affect the support of inertial mass part 20 in axial direction 4, 6 on base part 18. This does not need to exclude that inertial mass part 20 is supported or is supportable in at least one of axial directions 4, 6 on another component within a drivetrain; it is however preferred if inertial mass point 20 is supported or is supportable exclusively via lever element 30 in axial direction 4 and/or 6. List of references

2 Rotational vibration damper

4 Axial direction

6 Axial direction

8 Radial direction

10 Radial direction

12 First circumferential direction

14 Second circumferential direction

16 Axis of rotation

18 Base part

20 Inertial mass part

22 Outer side

24 Inner side

26 Reset device

28 Spring unit

30 Lever element

32 Force transmission element

34 Pivot point

36 First lever section

38 Second lever section

40 Support track

42 Articulation point

44 Articulation point

46 Spring element

48 Flexible/leaf spring

50 Clamp

52 Radial

54 Spring section

56 Support part

58 Reset force engagement point

60 Roller 62 Roller axis

64 Roller bracket

66 Set force engagement point

68 Set force

70 Reset force

72 Radial

74 Force transmission element

76 Articulation point

78 Set force engagement point 80 Articulation point

82 Spring section

84 Spring element

86 Support

88 Groove

90 Groove a Clamping length

b Effective length

ri Radial distance

r₂ Radial distance

r₃ Radial distance

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) counter to the reset force (70) of a reset device (26), wherein the reset device (26) has a spring unit (28) for generating a set force (68) and a lever element (30) arranged on the base part (18) and pivotable around a pivot point (34), via which lever element the set force

(68) is transmittable while generating the reset force (70) affecting the inertial mass part (20), characterized in that the inertial mass part (20) is supported or is supportable on the base part (18) in the radial direction (8, 10) by the lever element

(30) .

The rotational vibration damper (2) according to Claim 1, characterized in that a support part (56) is provided on the inertial mass part (20), via which support part the inertial mass part (20) is supported or is supportable at a reset force

engagement point (58) on the lever element (30), wherein the support part (56) is preferably moveable by rotating the inertial mass part (20) relative to the base part (18) while changing the reset force engagement point (58) along the lever element (30), and is formed particularly preferably by a roller (60) which can roll on the lever element (30) .

The rotational vibration damper (2) according to Claim 2, characterized in that the lever element (30) has two lever sections (36, 38), wherein the support part (56) is supported or is supportable on the one lever section (36) during rotation of the inertial mass part (20) out of a starting rotational position relative to the base part (18) in the one circumferential direction (12) and on the other lever section (38) during rotation of the inertial mass part (20) out of the starting rotational position relative to the base part (18) in the opposite circumferential direction (14), wherein the lever element (30) is preferably arranged in a starting pivot position in the starting rotational position of the inertial mass part (20), in which starting pivot position the lever element (30) is held by the, if necessarily detensioned, spring unit (28) and/or into which starting pivot position the lever element (30) is pretensioned by the spring unit (28) and/or in which starting pivot position the lever element (30) extends transversely, if necessary at right angles, to a radial (72) through the reset force engagement point (58) .

The rotational vibration damper (2) according to Claim 3, characterized in that the two lever

sections (36, 38) are arranged on diametrically opposite sides of the pivot point (34), wherein the pivot point (34) and the reset force engagement point (58) are preferably arranged in the starting pivot position of the lever element (30) on a common radial {12) .

The rotational vibration damper (2) according to one of Claims 2 through 4, characterized in that a support track (40) is provided on the lever element (30), along which support track the support part (56) can be moved by rotating the inertial mass part (20) relative to the base part (18), wherein the support track (40) has a course deviating from a straight-line course, preferably arch shaped or circular arc shaped, and the support part (56) is accommodated or is accommodatable particularly preferably by the support track (40) in a trough^¬ like or bowl-like way.

The rotational vibration damper (2) according to one of the preceding claims, characterized in that the inertial mass part (20) is further supported or is further supportable on the base part (18) in at least one axial direction (4; 6), if necessary in both axial directions (4, 6), via the lever element

(30), wherein the support part (56) is preferably supported or is preferably supportable on the lever element (30) in at least one of the axial directions

(4; 6), if necessary in both axial directions (4, 6) , and the support part (56) formed as a roller

(60) extends particularly preferably into a groove

(90) in the lever element (30), or the roller (60) has a groove (88) in the outer side thereof into which the lever element (30) extends.

The rotational vibration damper (2) according to one of the preceding claims, characterized in that the set force (68) of the spring unit (28) is

transmittable via at least one force transmission element (32; 74), preferably a force transmission lever, from the spring unit (28) to a set force engagement point (66; 78) on the lever element (30) .

The rotational vibration damper (2) according to one of the preceding claims, characterized in that the spring unit (28) has at least one flexible spring or leaf spring (48) which extends preferably along a radial (52) and at which flexible- or leaf spring a spring section (54) arranged inwardly in the radial direction (10) is particularly preferably clamped.

The rotational vibration damper (2) according to one of the preceding claims, characterized in that the reset force characteristic curve of the reset force (70) affecting the inertial mass part (20) can be changed, wherein preferably the set force

characteristic curve of the set force (68) exerted by the spring unit (28) on the lever element (30) can be changed while changing the reset force characteristic curve, and the set force

characteristic curve of the spring unit (28) having at least one flexible spring or leaf spring (48) can be changed particularly preferably by changing an effective length (b) of the flexible spring or leaf spring (48), if necessary by changing the clamping length (a) of the flexible spring or leaf spring (48) . 10. The rotational vibration damper (2) according to one of the preceding claims, characterized in that the inertial mass part (20) is formed as rotatable relative to the base part (18) and/or with an annular shape or an annular disk shape while

maintaining a predetermined radial distance (r₂) to the rotational axis (16) .

The rotational vibration damper (2) according to one of the preceding claims, characterized in that the lever element (30) is formed as bend-proof or rigid and/or the inertial mass part (20) is supported or is supportable exclusively via the lever element (30) in the radial and/or axial direction (8, 10; 4, 6) or is supported or is supportable on the base part (18) . The rotational vibration damper (2) according to one of the preceding claims, characterized in that at least two or three reset devices (26) are provided, which are preferably arranged in the circumferential direction (12, 14) at a uniform distance from each other, wherein the pivot movements of the lever elements (30) of at least two reset devices (26) are particularly preferably coupled to each other, if necessary via the reset devices (26) themselves, and/or one spring unit (28) is assigned to at least two reset devices (26) .