CN112065924B

CN112065924B - Belt pulley decoupler with rotational axis

Info

Publication number: CN112065924B
Application number: CN202010528945.6A
Authority: CN
Inventors: M·黑斯勒; A·斯塔弗尔; L·索瑞特; A·鲁施; M·凯斯勒
Original assignee: Schaeffler Technologies AG and Co KG
Current assignee: Schaeffler Technologies AG and Co KG
Priority date: 2019-06-11
Filing date: 2020-06-11
Publication date: 2024-06-28
Anticipated expiration: 2040-06-11
Also published as: DE102019115747A1; CN112065924A

Abstract

The invention relates to a belt pulley decoupler (1) having a rotational axis (2) for a belt drive (3) of an internal combustion engine (4), the belt pulley decoupler (1) comprising a torsional vibration damper (5) comprising at least: an input side (6); an output side (7); at least one intermediate element (8, 9, 10) between the input side and the output side; two rolling bodies (11, 12) of each intermediate element, the intermediate element having two transmission tracks (13, 14), the input side and the output side having complementary counter tracks (15, 16), respectively, between which the rolling bodies are guided in a rolling manner; and at least one energy storage element (17, 18, 19) by means of which the intermediate element is supported in a vibratable manner. The energy storage elements are arranged with a vector component (20) acting on the intermediate elements in the circumferential direction (22) and/or with only rolling bodies being provided as rolling bodies for the respective intermediate element.

Description

Belt pulley decoupler with rotational axis

Technical Field

The invention relates to a belt pulley decoupler having a rotational axis of a belt drive for an internal combustion engine, a belt drive for a drive train having such a belt pulley decoupler, a drive train having such a belt drive, and a motor vehicle having such a drive train.

The invention relates to a belt pulley decoupler for a belt drive of an internal combustion engine, said decoupler comprising a torsional vibration damper having at least:

-an input side;

-an output side;

-at least one intermediate element between the input side and the output side;

-two rolling bodies per intermediate element, wherein the at least one intermediate element has two transmission tracks, wherein the input side and the output side each have complementary corresponding tracks, wherein the rolling bodies are guided in a rolling manner between the respective transmission track and the complementary corresponding track; and

-At least one energy storage element by means of which the at least one intermediate element is vibratable supported.

The belt pulley decoupler is primarily characterized in that the energy storage elements are arranged with a vector component acting on the respective intermediate element in the circumferential direction and/or that only rolling bodies are provided as rolling bodies for each intermediate element.

Background

In belt drives that are excited with periodic disturbances (for example in auxiliary drives of internal combustion engines), the pulley decoupler acts as a torsional compliance (Torsionsnachgiebigkeit) that is introduced for the pulley of the driven device. The aim is to shift the resonance occurring in a rotational speed range as far as possible below the operating rotational speed. In order to be able to achieve a largely supercritical operation (with good vibration isolation of the output from disturbances) on the drive of the belt drive, the aim is to achieve as high a torsional compliance, i.e. a low torsional stiffness, as possible. The pulley decoupler must, however, simultaneously meet a maximum drive torque, which requires correspondingly large torsion angles with low torque stiffness. However, in a given installation space, the torsion angle that can be assumed is naturally limited by the capacity of the energy store used and the components in the torque flow that are sufficiently firmly configured.

Various types of torsional vibration dampers are known from the prior art. For example, a torsional vibration damper is known from EP 2,508,771 A1, in which a (double) cam is provided on the output side, which cam acts on a rod-shaped intermediate element, wherein the intermediate element is connected in a tiltable manner to a disk on the input side. The intermediate element is preloaded against the output-side cam by means of a compression spring and is biased against the compression spring when passing through the cam geometry. The compression spring is connected to the input side opposite the intermediate element in a pressure-transmitting manner, so that torque is guided from the input side to the output side by the compression spring.

A further variant of a torsional vibration damper is known from FR 3,057,321 A1, in which a rod-shaped spring body is provided on the output side, which spring body is of the type in the form of a (free-form) solid spring, wherein the spring body has a radially outer ramp-shaped transmission rail which is connected in torque-transmitting manner to rollers which roll on the transmission rail. The roller is rotatably supported on the pin. If torsional vibrations occur, a relative movement is induced between the spring body and the respective roller, and the spring body is offset in a rod-like manner from the roller against its spring force in its rotational relative movement with respect to the roller due to the ramp-like transmission track. Thereby damping torsional vibrations.

Both the rod of EP 2 508 771 A1 and the spring body of FR 3 057 323 A1 are technically difficult to master and/or expensive to manufacture or assemble if low dissipation, i.e. high efficiency, is desired.

For example, a torsional vibration damper is known from WO 2018/215 A1, in which two intermediate elements are provided, which are supported on the output side and the input side by rolling bodies. The rolling bodies run on complementary drive tracks, so that the intermediate element is positively guided. The two intermediate elements are preloaded relative to each other by means of the energy storage elements, so that the functionally effective stiffness of the energy storage elements can be designed independently of the torque transmission. For a variety of applications, it is desirable to reduce the natural frequency of the torque transmission system and at the same time be able to transmit high torque. Starting from the first requirement, the functionally effective stiffness must be low. From the second requirement, the rigidity of the energy storage element must be high. These contradictory requirements can be solved by means of the rolling bodies and the transmission track. Torque is transmitted between the input side and the output side only by means of the transmission track and the rolling bodies arranged between them. The functionally effective stiffness, i.e. the change in natural frequency, translates into a small spring travel due to the small slope and the large torsion angle. The (arbitrary) small functional effective stiffness is caused by the cam gear. It is therefore advantageous in this system to be able to design the energy storage element independently of the (maximum) transmissible torque. However, the illustrated embodiment with a large number of individual rolling bodies and high demands on the complementary transmission track is complex and expensive to produce and assemble. Thus, the system is not competitive in all areas.

Disclosure of Invention

Starting from this, the object underlying the invention is to at least partially overcome the disadvantages known from the prior art. The features according to the invention result from the independent claims, advantageous configurations of which are listed in the dependent claims. The features of the claims can be combined in any technically meaningful way, wherein for this purpose the features from the description below and from the drawings, which comprise additional configurations of the invention, can also be considered.

In the following, reference is made to the axis of rotation if no other explicit description of the axial direction, radial direction or circumferential direction and the corresponding concepts is given. Unless explicitly stated otherwise, ordinal numbers used in this description are used for clarity of distinction only and do not reflect the order or level of the noted components. Ordinal numbers greater than one also do not necessarily mean that another such component must be present.

The invention relates to a belt pulley decoupler having a rotational axis for a belt drive of an internal combustion engine, wherein the belt pulley decoupler comprises a torsional vibration damper having at least the following components:

-an input side for receiving torque;

-an output side for outputting torque;

-at least one intermediate element in a torque transmitting connection between an input side and an output side;

-a first rolling element and a second rolling element of each intermediate element, wherein the at least one intermediate element has a first transmission track for the rolling of the first rolling element and a second transmission track for the rolling of the second rolling element, wherein the input side has a first counter track complementary to the first transmission track and the output side has a second counter track complementary to the second transmission track, wherein the first rolling element can be guided in a rolling manner between the first transmission track and the first counter track and the second rolling element can be guided in a rolling manner between the second transmission track and the second counter track. And

-At least one energy storage element by means of which an intermediate element corresponding to the energy storage element is vibratably supported.

The main feature of the belt pulley decoupler is that the energy storage elements are arranged with a vector component in the circumferential direction acting on the corresponding intermediate element.

A belt pulley decoupler is proposed here, which is suitable for use in a belt drive having at least two belt pulleys, namely at least one drive pulley and at least one driven pulley, which are connected to one another in a torque-transmitting manner by means of a belt. Such belt drives are used, for example, in internal combustion engines, wherein the drive disk is connected indirectly or directly to a burner shaft (Verbrennerwelle) which serves as a torque source, for example, in the main operating state of the internal combustion engine. The driven disk is connected, for example, to a rotor shaft of an auxiliary device, for example an air conditioning compressor or a motor generator. The pulley decoupler can be used not only in the drive pulley but also in the driven pulley. For many applications the pulley decoupler does not allow for deviations in its mounting dimensions from the conventional mounting dimensions of the respective pulley, but for most applications the pulley decoupler does not at least allow for greater than conventional pulley decouplers with suitable vibration decoupling or advantageously changing the resonant frequency.

It is now proposed to use a torsional vibration damper configured as follows. The torsional vibration damper proposed here has a small number of individual components and only a small number of rolling bodies and complementary transmission tracks, which are referred to as transmission tracks on the intermediate element side and as (complementary) counter tracks on the input side and the output side. The input side is here provided for receiving a torque, wherein it is not excluded here that the input side is also provided for outputting a torque. For example, the input side forms the torque input in the main state (for example, in the case of so-called drag torques from the torque output of the drive shaft, i.e. the internal combustion engine and/or the electric machine). The output side is correspondingly provided for outputting torque, wherein the output side is preferably also provided for receiving torque (e.g. from a motor generator) for starting the internal combustion engine. The output side thus constitutes the input side of a so-called driving torque, for example, when the belt drive of the drive train is used in an auxiliary state, i.e. in the above-described embodiment at least one auxiliary device outputs the input torque to the internal combustion engine.

In order that the torsional vibrations are not transmitted directly from the input side to the output side, or vice versa, at least one intermediate element, preferably at least two intermediate elements, is provided. At least one intermediate element is arranged in the torque transmitting connection between the input side and the output side. The at least one intermediate element can be moved relative to the input side and relative to the output side, so that torsional vibration energy is introduced into the intermediate element and thus onto the energy storage element with a predefined (functionally effective) stiffness. Thus, the natural frequency of a system incorporating a torsional vibration damper, its function of mass and stiffness, can be varied, preferably reduced.

The intermediate element is supported on itself or on an adjacent intermediate element by means of at least one energy storage element, for example a curved spring, a leaf spring, a gas pressure accumulator or the like. The energy storage elements are supported in a force-or torque-transmitting manner on the respective connection means of the corresponding intermediate element, which are preferably in one piece. For example, the connection means are abutment surfaces and/or rivet locations.

At least one intermediate element is supported on the input side and the output side by means of rolling bodies connected in series, wherein the intermediate element has a drive track for each of the rolling bodies and forms complementary counter tracks for the same (counter) rolling body on the input side and the output side, respectively. The complementary counter track is formed by the output side or by the input side, preferably in one piece with the input side and the output side, respectively. Torque is transmitted through the corresponding track and the drive track. Torque is not transferred between the input side and the output side through the at least one energy storage element.

For example, if a torque is introduced, for example, from the input side, the rolling bodies roll on the transmission track and the complementary counter track from the rest position in the respective direction (upward) on the ramp-like transmission track, due to the torque gradient that is present due to the torsional vibration damper. The upward scrolling is referred to herein as doing work for illustration only. Rather, the reaction force of the energy storage element is overcome due to the geometrical relationship. Thus, rolling down means outputting the energy stored by the energy storage element in the form of a force acting on the corresponding intermediate element. Therefore, the upward and downward do not necessarily correspond to the spatial direction, even in the coordinate system with rotation.

With this torque-dependent movement, the rolling bodies force a relative movement of the respective intermediate element with respect to the input side and the output side, and the opposing energy storage element is correspondingly tensioned. For example, in the case of torsional vibrations, if the applied torque changes and at the same time a rotational speed difference occurs between the input side and the output side, the inertia of the other (torque-absorbing) side, here the output side, is opposite to the applied torque, and the rolling bodies roll back and forth (in a predefined manner) on the transmission track and on the complementary counter track around a position corresponding to the applied torque. The rolling bodies thus do work against the energy storage element which is tensioned as a function of the torque magnitude, so that the natural frequency changes compared to the torque transmission in the rest position or without a torsional vibration damper (but with the same following flywheel mass).

The force is received in the form of compression, tension, torsion or other energy storage by the correspondingly embodied energy storage element and is transmitted with a time delay, preferably (almost) without dissipation, to the respective other side, here for example the output side. The torque input (here, for example, on the input side) comprising torsional vibrations is thus transmitted, preferably (almost) loss-free, time-dependent, to the output side, for example. Furthermore, as mentioned above, the natural frequency is not constant, but depends on the torque gradient and thus on the applied torque due to the changeable position of the intermediate element.

In the opposite case of the torque input via the output side for output to the input side, the rolling bodies are correspondingly caused to roll (upward) on the transmission track in the other (opposite to the previously described torque input via the input side). Such a movement of the rolling bodies causes the energy storage elements to be loaded in the other direction or, in the case of a paired arrangement, to be unloaded at, for example, a first energy storage element loaded in accordance with the above-described embodiment and loaded at a respective other, for example, a second energy storage element. When two or more intermediate elements are supported on opposite sides by means of corresponding (common) energy storage elements in a circular arrangement, all energy storage elements are tensioned, for example in the manner of a screw clamp, by means of a radially inward movement of the energy storage elements.

When the torque changes, as occurs in torsional vibrations, the at least one energy storage element is displaced about a position corresponding to the applied torque, and the stored energy is transmitted in the form of a changing, i.e. delayed movement, in conjunction with rolling bodies rolling between the respective transmission track and the complementary counter track, to the output side. Thereby, the natural frequency of the torque transmission system to which the torsional vibration damper is connected is changed.

In one embodiment, two or more intermediate elements are provided, which are preferably arranged rotationally symmetrically with respect to the axis of rotation, so that the torsional vibration damper is balanced with simple means. For a small number of parts and (transmission) rails, an embodiment with exactly two intermediate elements is advantageous.

Preferably, two energy storage elements are provided for acting on the (single) intermediate element, wherein the energy storage elements are arranged opposite each other and preferably enter a state of equilibrium with each other in correspondence with the embodiment of the transmission track and the complementary counter track. In an alternative embodiment, at least one positive guide is provided, by means of which at least one of the intermediate elements is guided geometrically, for example forced in the manner of a rail or groove and a gripping pin or embedded spring.

According to this proposal (which deviates from the embodiments proposed below), the energy storage elements act on the corresponding intermediate element in the direction of the force with a vector component in the circumferential direction. The circumferential direction is defined on a circle concentric with respect to the rotation axis. In one embodiment, the circumferential direction is constantly oriented by a movement of the corresponding intermediate element, is oriented migration on a constant circle or is oriented constant or migration on a variable circle. The circle is at least so large that it contacts the intermediate element, preferably so large that it intersects a contact point or is tangential to a contact surface, at the location of which the force is transferred between the associated energy storage element and the corresponding intermediate element. The circumferential direction is oriented perpendicularly to a radius centered on the axis of rotation. The respective base radii intersect the contact points or contact faces of the energy storage element and the intermediate element. Thus, a force direction with a large vector component in the circumferential direction, preferably a force direction with a vector component in the circumferential direction that is greater than the vector component in the radial direction, is produced on the intermediate element. That is to say that the forces acting on the intermediate element are not purely radially oriented, but are tangential to the circumferential direction only (at the contact point) or have a radial vector component and have a tangential vector component (at the contact point). Hereby is obtained a force direction which can be conducted into the same intermediate element, for example by means of a helical arc spring (from the other side), or which can be conducted substantially in the circumferential direction into an adjacent intermediate element. This can, for example, replace an offset (or vibration) of the energy storage element only in the (radial) transverse direction, in addition to or only in the circumferential direction.

In an advantageous embodiment, the intermediate element is supported here by the rolling bodies in an insufficiently defined manner, for example only in a radially defined manner, wherein the at least one energy storage element defines the movement due to the force introduction direction, for example only in the circumferential direction. Alternatively, additional guidance is provided for the intermediate element.

The torsional vibration damper proposed here can be implemented in a small installation space due to its relatively small number of components and can also be produced at low cost. In addition, torsional vibration dampers can be used for large torques to be transmitted while the vibration stiffness is very low, since the ramp-like transmission track (and the complementary counterpart track) produces a rolling transmission which approximates an arbitrary reduction ratio. The reduction ratio has an effect on the required spring travel, and therefore the stiffness of the rigid energy storage element is reduced, i.e. softer, due to the extended effective spring travel by means of the rolling transmission.

According to another aspect, a belt pulley decoupler is provided having a rotational axis for a belt drive of an internal combustion engine, wherein the belt pulley decoupler comprises a torsional vibration damper having at least the following components:

-an input side for receiving torque;

-an output side for outputting torque;

-at least two intermediate elements in a torque transmitting connection between an input side and an output side;

a first rolling body, a second rolling body of each intermediate element,

Wherein the intermediate element has a first transmission track for the rolling of the first rolling bodies and a second transmission track for the rolling of the second rolling bodies,

Wherein the input side has a first counter track complementary to the first drive track and the output side has a second counter track complementary to the second drive track, wherein the first rolling bodies are guided in a rolling manner between the first drive track and the first counter track and the second rolling bodies are guided in a rolling manner between the second drive track and the second counter track; and

A plurality of energy storage elements, corresponding to the number of intermediate elements, by means of which the respective intermediate element corresponding to the energy storage element is supported in a vibratable manner,

Wherein each of the intermediate elements is supported on a respective at least one adjacent intermediate element by means of a corresponding energy storage element.

The pulley decoupler is primarily characterized in that only the first rolling element and the second rolling element are provided as rolling elements for each intermediate element.

The pulley decoupler is proposed here according to the function described above and in this respect reference is made to the description above. Furthermore, with regard to torsional vibration dampers, reference is made to the previous explanation of the basic principle, and to the definition and interrelationship between the input side, the output side, the respective intermediate element and the corresponding energy storage element, and the rolling bodies and the corresponding transmission track and the corresponding track. In contrast to the previous description, at least two intermediate elements and at least one, preferably two, energy storage elements must be provided, wherein these intermediate elements are supported in a force-transmitting manner relative to one another by means of the at least one energy storage element.

According to this proposal (which deviates from the previously mentioned proposed embodiments), at least one energy storage element must be supported by the rolling elements in an insufficiently defined manner, for example in a manner which is defined only in the radial direction, in that only two rolling elements, i.e. only one (for example the first) rolling element for the input side and only one (for example the second) rolling element for the output side, are provided in the respective intermediate element. The at least one energy storage element, which acts on the intermediate element and is supported on the at least one (directly) adjacent intermediate element, for example, defines a movement due to the force introduction direction only in the circumferential direction. For a reliable configuration, for example, a positive guide is additionally provided, by means of which the movement of the respective intermediate element is (geometrically) excessively limited.

It is furthermore proposed that the torsional vibration damper has the features of the above-described embodiments.

In this embodiment, the respective intermediate element of the plurality of intermediate elements is therefore supported by means of only two rolling bodies, i.e. in an indeterminate manner or only exactly definitely, as long as the forces for the fixing of the position of the transmission rail relative to the complementary counter rail and the rolling bodies rolling between them are maintained irrespective of the degree of freedom deliberately achieved on the transmission rail, for example implemented as an insignificant equilibrium position. This force is supported, for example, in operation by inertial reactions to centripetal forces (centrifugal forces). The freedom of the drive track, which is deliberately achieved, for example, as an insignificant balance, is accommodated in a defined manner by the two energy storage elements. For example, rolling elements rolling on a transmission track (and a complementary corresponding track) result in a motion with radial and/or tangential vector components. Thereby, a path is followed which is stored as potential energy in at least one of the corresponding energy storage elements. Furthermore, the required force, for example a force acting only radially, is preferably also applied by the energy storage element, so that the counter rail and the drive rail are held relative to one another, so that the counter rolling bodies can only move between them in a rolling manner. The movement of the rolling bodies thus always causes a relative movement between the counter rail and the complementary drive rail and thus between the intermediate element and the input side and output side. Support in the radial direction and/or forced guidance of the intermediate element, for example by means of a large number of rolling bodies, is not required.

Furthermore, in an advantageous embodiment of the belt pulley decoupler, it is proposed that: exactly three intermediate elements and exactly three energy storage elements are provided, wherein the first intermediate element and the second intermediate element are supported by means of the first energy storage element, the second intermediate element and the third intermediate element are supported by means of the second energy storage element, and the first intermediate element and the third intermediate element are supported by means of the third energy storage element.

In this embodiment, on the one hand, the number of intermediate elements, transmission tracks, counter tracks, rolling bodies and energy storage elements is still small, while on the other hand, the costs in terms of manufacturing tolerances of the transmission tracks and counter tracks are reduced compared to a forced guidance with more than two rolling bodies per intermediate element. In this embodiment, deviations from the ideal orientation of the intermediate element in the rest position, which are predetermined by the geometric conditions, for example, are determined by the production, are tolerable to a greater extent within the scope of the design and/or can be compensated for by the energy storage element during the calibration process.

Furthermore, in an advantageous embodiment of the belt pulley decoupler, it is proposed that: the at least one intermediate element is supported exclusively by means of the at least one corresponding energy storage element and by means of the rolling bodies.

In this embodiment, the intermediate element is brought to a stable equilibrium without additional (forced) guiding elements by means of the interaction of the drive rail, the complementary counter rail and the respective rolling bodies with the corresponding energy storage elements only. A stable equilibrium means that the intermediate element cannot be pulled out of the setpoint position at least by a torque amplitude and a torque oscillation according to the design. At least for mobile applications, the balancing is stable, so that (as designed) lateral forces, such as tremors, cannot also pull this arrangement out of the nominal position, for example, the rolling bodies cannot be removed from one of their tracks. The vector component of the force of the energy storage element in the radial direction or perpendicular to the (application section of the) drive track and the corresponding track is always greater than the (external) force to be removed.

This ensures that the force direction of the introduced force of the energy storage element, i.e. the orientation of the force vector along or parallel to the line of action, intersects the line of action of the resultant (counter) force caused by the rolling bodies, which extends through the rolling center (rolling axis) of the rolling bodies and is oriented perpendicularly to the transmission track and the complementary corresponding track, independently of the offset of the intermediate element at the moment equilibrium point of the intermediate element. Thus, there is a moment balance on the intermediate element around the moment balance point of the intermediate element. In essence, this force proportion thus corresponds to the force proportion of the force vector or energy storage element introduced by the rolling elements and acting on the intermediate element. That is, the force of the energy storage element increases, so does the resultant force caused by the rolling elements in this structural rule. The force vectors in the two opposing energy storage elements thus form a (closed) force polygon, i.e. the sum of the forces is zero according to the vector addition principle.

Furthermore, in an advantageous embodiment of the torsional vibration damper, it is proposed that: the two rolling bodies are arranged at a distance from each other in the radial direction.

The advantage of this embodiment is that a small installation space is required in the circumferential direction, so that, for example, the intermediate element can be implemented in a narrow manner in the circumferential direction and thus more installation space can be provided for the energy storage element, and thus, for example, a large torsion angle and thus a small functional rigidity can be provided at the same time as a high rigidity of the at least one energy storage element.

Furthermore, in an advantageous embodiment of the torsional vibration damper, it is proposed that: the two rolling bodies are arranged at a distance from each other in the circumferential direction.

An advantage of this embodiment is that a small radial space is required, so that for example the intermediate elements can be arranged on a large circumferential circle and thus a large torsional angle and thus a small functional stiffness can be provided at the same time as a large stiffness of the at least one energy storage element. Alternatively or additionally, the torque can be transmitted via the same transmission track and thus with equal magnitude.

In an advantageous embodiment of the torsional vibration damper, it is furthermore provided that the two rolling bodies are arranged radially and in the circumferential direction at a distance from one another.

In this embodiment, the advantages of the above embodiments can be combined with each other or can be approximated to an ideal case with small deviations, respectively.

Furthermore, in an advantageous embodiment of the belt pulley decoupler, it is proposed that: the transmission track and the respective complementary counter track each comprise a traction torque pair having a first transmission curve and a propulsion torque pair having a second transmission curve, wherein the traction torque pair is provided for transmitting torque from the input side to the output side, wherein the propulsion torque pair is provided for transmitting torque from the output side to the input side, wherein the first transmission curve and the second transmission curve have transmission profiles which differ from each other at least in some regions.

Basically, the traction torque and the propulsion torque are not different in the case of theoretical applications. Accordingly, these terms should be considered neutral and are used simply to distinguish between noted torque transfer directions. These terms are taken from the generic names in the drive train of a motor vehicle, but can be transferred to other applications accordingly. The traction torque pair is applied in the transmission of the traction torque, for example from the input side to the output side, wherein the rolling bodies on the traction torque pair roll (upward) against the opposing force of the energy storage element as the torque increases. Thus, the potential energy of the opposing energy storage element increases, e.g. is tensioned and thereby changes the stiffness. Thus, torsional vibrations resist the greater force of the opposing energy storage element with increased torque, and the natural frequency is thus changed. This applies correspondingly to the pair of driving torques, on which the rolling bodies are forced to roll (upwards) due to the load of the energy storage element.

In this embodiment, the first transmission curve and the second transmission curve, each starting from a common point of rest position, are provided with different transmission profiles. The stiffness characteristics of the torsional vibration damper can thus be set individually for the traction torque and the propulsion torque (differently).

In one embodiment, for example, a small stiffness is required for transmitting the traction torque, which can be achieved accordingly by a larger torsion angle (smaller reduction ratio, i.e. smaller denominator of the transmission ratio) than is desired for the propulsion torque (larger reduction ratio). Furthermore, for example, an increasing or decreasing stiffness profile is desired, or even a stiffness profile that is changed a plurality of times is desired. For example, a small stiffness rise is provided in the region near idle, a steep stiffness rise is provided for the main load torque, which is in turn gradually decreasing, and an increasing stiffness rise is provided again until the maximum transmission value for which torque can be transmitted is reached.

The transmission track and the complementary counter track are designed in this case in accordance with the respective offset position of the intermediate element, so that the transmission curve is embodied in superposition with the movement of the intermediate element. The drive rail and the complementary counter rail are preferably implemented as described above for torque balancing, preferably such that no additional (positive) guide means are required for the intermediate element.

Furthermore, in an advantageous embodiment of the torsional vibration damper, provision is made for: the at least one intermediate element is preloaded by means of two opposing energy storage elements.

In this embodiment, the pretensioning of the energy storage element against the rolling bodies by the intermediate element or elements is reliably adjustable in a well-controlled manner. For example, in the case of identical energy storage element structures, the dependency on component tolerances, for example the spring characteristic of the energy storage elements, is small, in that the tolerances are reduced with respect to one another, for example the stiffness deviating downwards from the nominal stiffness of the first energy storage element is compensated or reduced by the stiffness deviating upwards of the second energy storage element. In the case of identical deflection, the pretension is reduced or increased as a whole compared to the nominal pretension, but is compensated for by the counteracting effect, for example on both sides of the intermediate element. In one embodiment, only the rest position of the intermediate element is changed. The tolerance is preferably small enough that the rest position remains within a predefined tolerance range. In embodiments with three intermediate elements, the (three) energy storage elements are connected to each other such that the first (or second) energy storage element of the first intermediate element is also in antagonistic connection with the second (or first) energy storage element of the second intermediate element and a compensating effect is achieved for the component tolerances of the energy storage elements. Overall, therefore, the required manufacturing accuracy, assembly or calibration effort and/or the costs of standard components are reduced due to the lower component mass.

Furthermore, in an advantageous embodiment of the torsional vibration damper, provision is made for: the at least one intermediate element is preloaded by means of two opposing energy storage elements, wherein preferably the first energy storage element applies a first force and a first force direction to the respective intermediate element and the second energy storage element applies a second force and a second force direction to the respective intermediate element, wherein the first force and the second force differ from each other in the rest position and/or the first force direction and the second force direction differ from each other in the rest position.

A helical compression spring with a straight spring axis, also known as a (pure) cylindrical helical compression spring, is a widely used standard component, the elasticity and (low) dissipation properties of which are well utilized and can be controlled simply. The tolerances in the structural length or the tolerances in the spring properties over a predefined installation length can be compensated for by simple means. Furthermore, such helical compression springs do not require additional guidance, which would otherwise cause friction and thus would have reduced efficiency and/or would have more difficult damping characteristics to determine due to hysteresis. Furthermore, a helical compression spring enables large variations in the spring characteristic, which can be adjusted in particular by the helical pitch, the wire thickness, the ratio of the installation length to the relaxation length and the material selection.

Furthermore, helical compression springs with a straight spring axis are fracture-resistant compared to springs of other construction types, for example steel springs, and can be loaded and compacted in some embodiments, so that in the event of an overload on the torsional vibration damper according to the design, in such embodiments in which the energy storage element can be compacted, no additional securing element has to be provided to prevent the energy storage element from fracture. In addition, the helical compression spring has the following advantages: at the same time as the spring rate is high, a long spring travel is possible, so that on the one hand a large torque can be introduced via the at least one energy storage element, and on the other hand a suitable reduction gear ratio can be set by means of the drive track, so that a reduced movement amplitude of the intermediate element is achieved with respect to the amplitude of the torsional vibrations, and thus torsional vibrations in the very small spring travel of the helical compression spring are induced. As a result, the helical compression spring resists torsional vibrations with (suitably) small forces despite the high stiffness.

Furthermore, in an advantageous embodiment of the belt pulley decoupler: at least one of the energy storage elements is a helical compression spring having a straight spring axis.

Furthermore, helical compression springs with a straight spring axis are fracture-resistant compared to springs of other construction types, for example steel springs, and can be loaded and compacted in some embodiments, so that in the event of an overload on the torsional vibration damper according to the design, in such embodiments in which the energy storage element can be compacted, no additional securing element has to be provided to prevent the energy storage element from fracture. In addition, the helical compression spring has the following advantages: at the same time as the spring rate is high, a long spring travel is possible, so that on the one hand a large torque can be guided by the at least one energy storage element, and on the other hand a suitable reduction gear ratio can be set by means of the drive track, so that a reduced movement amplitude of the intermediate element is achieved with respect to the amplitude of the torsional vibrations, and thus torsional vibrations in the very small spring travel of the helical compression spring are induced. As a result, the helical compression spring resists torsional vibrations with (suitably) small forces despite the high stiffness.

According to another aspect, a belt drive for a drive train is proposed, which has at least the following components:

-a first pulley for connection with a drive shaft of a drive machine;

-a second pulley for connection with a rotor shaft of an auxiliary device; and

A belt connecting the first pulley and the second pulley in a torque-transmitting manner,

Wherein the first pulley and/or the second pulley comprises a pulley decoupler according to any one of the preceding claims.

The belt drive is provided for transmitting torque from the drive machine to the auxiliary device and vice versa, for example in the case of a motor generator as auxiliary device. For this purpose, belt pulleys are respectively arranged in a torque-proof manner on at least two connected shafts, namely on at least one drive shaft of at least one drive machine (for example an internal combustion engine) and on at least one rotor shaft of at least one auxiliary device (for example an air-conditioning compressor). A belt is tensioned on the belt pulley in such a way that a friction-or form-locking torque can be transferred to the other belt pulley as a traction force (traction means, for example V-belt) or as a pushing force (push chain belt). At least one of the belt pulleys, preferably the belt pulley on the drive shaft embodied as a crankshaft, comprises a belt pulley decoupler with a torsional vibration damper according to the previously described embodiments. Thus, by means of a suitable displacement of the natural frequency range of the belt drive, torsional vibrations are decoupled from the rest of the belt drive, for example the rotor shaft of the auxiliary device. At the same time, the pulley decoupler can be implemented with a small installation size, so that it can be integrated into a conventional pulley, despite the fact that it meets the general transmission ratio requirements (i.e. the diameter ratio of the pulley).

According to another aspect, a drive train is proposed, which has at least the following components:

-a drive machine having a drive shaft;

-an auxiliary device having a rotor shaft; and

The belt drive according to the embodiment described above, by means of which the drive machine and the auxiliary device are connected to each other in a torque-transmitting manner.

The drive train is provided for transmitting torque, which is provided by a drive machine, for example an internal combustion engine or an electric drive machine, and which is output via a driven shaft thereof, to at least one consumer. In the case of applications in motor vehicles, exemplary consumers are at least one drive wheel for propelling a motor vehicle, for example a motorcycle, and auxiliary devices, for example a generator for supplying electrical energy. In one embodiment, a plurality of drive machines are provided, for example an internal combustion engine in a hybrid drive train and at least one electric machine, for example a motor generator. Such a motor generator for example forms an auxiliary device and serves both for receiving torque (for generating electrical energy) and for outputting torque (for starting the internal combustion engine). The belt drive enables torque transmission between the auxiliary device and the drive machine, wherein the natural frequency is suitably shifted in at least one of the belt pulleys by means of the belt pulley decoupler, so that the torque receiving device, for example the auxiliary device, is protected from resonance oscillations, i.e. vibration decoupling. The belt drive proposed herein has a small installation size and can replace conventional belt drives without other required changes. Furthermore, the efficiency is improved with respect to systems with other decoupling means.

According to a further aspect, a motor vehicle is provided, which has at least one drive wheel which can be driven by means of a drive train according to one of the embodiments described above.

Most motor vehicles now have a front wheel drive and drive machines, for example internal combustion engines and/or electric drive machines, are arranged partially in front of the cab and transversely to the main driving direction. The radial installation space is only very small in this arrangement and therefore the use of a drive train with components of small installation dimensions is particularly advantageous. The drive train installation in a motor-driven two-wheeled vehicle is of similar design, which motor-driven two-wheeled vehicle always requires increased power compared to known two-wheeled vehicles while maintaining equal installation space. With the mixing of the drive trains, this problem is exacerbated for rear axle arrangements, and here not only in longitudinal arrangements but also in transverse arrangements of the drive assembly.

In the motor vehicle proposed here with the drive train described above, a high efficiency is achieved due to the high running smoothness and thus very constant belt tension in that a very efficient torsional vibration damper is integrated in at least one of the belt pulleys of the belt drive of the drive train. Meanwhile, the required installation space is at least not larger than conventionally used installation space, and the cost is not increased compared to the conventional vibration decoupling system.

Passenger cars correspond to vehicle classes according to, for example, size, price, weight and power, wherein this definition is subject to constant changes according to market demand. In the united states market, the vehicle class of small vehicles and micro vehicles corresponds to the ultra-small vehicle class according to the class of europe, and in the uk market, the vehicles of such small vehicles and micro vehicle class correspond to the ultra-mini class or city vehicle class. An example of a class of micro-car is the mass up-! Or reynolds Twingo. Examples of cart classes are alpha romidep MiTo, mass Polo, ford ka+ or reynolds Clio. The known full hybrid vehicle in the small class is BMW i3 or toyota Yaris hybrid.

Drawings

The above invention is explained in detail in the related art background with reference to the accompanying drawings showing preferred configurations. The invention is not limited to purely schematic illustrations, in which it should be noted that these drawings are not true to scale nor are they adapted to define dimensional relationships. Which shows

Fig. 1: the principle sketch of a first embodiment of a torsional vibration damper;

fig. 2: the principle sketch of a second embodiment of a torsional vibration damper;

fig. 3: schematic representation of the force exerted on the intermediate element;

fig. 4: a force polygon according to the force applied in fig. 3;

Fig. 5: a torque-torsion angle diagram having a first transmission curve;

Fig. 6: a torque-torsion angle diagram having a second transmission curve;

fig. 7: a torque-torsion angle diagram having a third transmission curve;

fig. 8: torque-torsion angle diagrams with fourth and fifth transmission curves;

Fig. 9: a simplified cross-sectional view of a belt pulley decoupler having a torsional vibration damper; and

Fig. 10: a motor vehicle having a drive train including a pulley decoupler.

Detailed Description

Fig. 1 and 2 each show, in schematic form, a different embodiment of a torsional vibration damper 5, which is shown as identical as possible for the sake of clarity, and which is cross-referenced for the description of the same components in the respective figures. The annular disk forms the output side 7. At the center of the common rotation axis 2, the other disk element is embodied, for example, as an input side 6. Alternatively, the annular disc is the input side 6 and the disc element is the output side 7. In the following, the variants mentioned above are described, wherein these terms are interchangeable.

As illustrated by the arrows, the traction torque 45 can be transmitted from the input side 6 to the output side 7, while the propulsion torque 46 can be transmitted from the output side 7 to the input side 6. In one embodiment, the torque direction is reversed.

Three intermediate elements 8, 9, 10 are arranged in an intermediate connection between the input side 6 and the output side 7, wherein the respective intermediate element 8, 9, 10 is connected in a force-transmitting manner to the respective adjacent intermediate element 8, 9, 10 by an energy storage element 17, 18,19 arranged in pairs. The respective intermediate element 8, 9, 10 is supported on the input side 6 by means of the first rolling bodies 11 and the respective intermediate element 8, 9, 10 is supported on the output side 7 by means of the second rolling bodies 12. The first rolling bodies 11 are supported in a rolling-able manner on the first transmission rail 13 on the intermediate element side, and the complementary first counter rail 15 is supported in a force-transmitting manner and thus in a torque-transmitting manner on the output side 6. The second rolling bodies 12 are supported in a rolling-able manner on the second transmission rail 14 on the intermediate element side, and the complementary second counter rail 16 is supported in a force-transmitting manner and thus in a torque-transmitting manner on the output side 7. The rolling bodies 11, 12 are preloaded against the drive tracks 13, 14 and against the counter tracks 15, 16 by means of the energy storage elements 17, 18,19 and are thus guided in a rolling manner on these tracks. In the shown position, the energy storage elements 17, 18,19 hold the intermediate elements 8, 9, 10 in the rest position against each other. In the first rolling element 11 and in the second rolling element 12 at the third intermediate element 10 (according to the notation in the first intermediate element 8) there is shown (for the sake of clarity, indicated in full with partial representations) in the rest position a traction moment pair 23 consisting of the respective complementary ramp portions of the transmission tracks 13, 14 and the corresponding tracks 15, 16, and on the respective other side a traction moment pair 25 consisting of the complementary ramp portions of the transmission tracks 13, 14 and the corresponding tracks 15, 16. Likewise, only for the sake of clarity, the traction moment pairs 23 on the first rolling elements 11 and correspondingly the propulsion moment pairs 25 on the second rolling elements 12 are shown in their entirety with partial representatives. However, these torque pairs are each formed by a transmission track 13, 14 on the intermediate element side and a complementary counter track 15, 16 on each of the rolling elements 11, 12. The manner in which these tracks operate is explained in detail below. In the embodiment shown, the intermediate elements 8, 9, 10 are supported on the input side 6 and the output side 7 only by means of the respective rolling bodies 11, 12, and the intermediate elements 8, 9, 10 are supported relative to one another by means of the energy storage elements 17, 18, 19. Preferably no additional guidance is provided.

In fig. 1, the first rolling element 11 and the second rolling element 12 of the respective intermediate element 8, 9,10 are arranged radially spaced apart from one another and lie on a common radius in the rest position. The first rolling elements and the second rolling elements are therefore not spaced apart in the circumferential direction 22 in the rest position.

Fig. 2 shows an alternative embodiment of the arrangement of the two rolling bodies 11, 12 of the respective intermediate element 8, 9, 10 relative to one another, wherein the two rolling bodies 11, 12 do not have a radial distance, but are spaced apart from one another in the circumferential direction 22. In the embodiment shown, the energy storage elements 17, 18, 19 are embodied in the same type and are arranged identically for better comparability.

According to the embodiment in fig. 1, a schematic diagram of the torque balance is shown in fig. 3, and a force polygon of the first intermediate element 8, the second intermediate element 9 or the third intermediate element 10 with the first rolling element 11 and the second rolling element 12 is shown in fig. 4. The intermediate elements 8, 9, 10 are guided out of their rest position and are inclined at an offset angle to the rest position and are offset to the rest line 47. The rest line 47 extends all the way through the moment balance point 48 of the intermediate element 8, 9, 10, but only through the rolling axes of the two rolling bodies 11, 12 in the rest position, but all the way through one of the two rolling axes (in this case the rolling axis of the second rolling body 12). If no additional (forced) guidance is required for the intermediate elements 8, 9, 10, a moment balance must be present at this moment balance point 48 of the intermediate elements 8, 9, 10. The resultant force directions 28, 30 via the rolling bodies 11, 12, i.e. the first pressure line 49 of the first rolling body 11 and the second pressure line 50 of the second rolling body 12, must always be oriented perpendicularly relative to the applied (theoretically infinitesimal) section of the drive track 13, 14 and extend through the torque compensation point 48. In order to always remain in compliance with this rule, a second parallel line of the first line of action 51 of the first force 27 from the first energy storage element 17 and a second equidistant or comparably spaced line of action 52 of the second force 29 from the other (e.g. third) energy storage element 19 intersect the two pressure lines 49, 50 at the moment balance point 48, so that no (effective) lever arm is generated. In order to properly compress the rolling elements 11, 12, the first force 27 and the second force 29 (here only shown at the second force 29) are divided into a tangential vector component 20 (functionally effective part) and a radial vector component 21 (compressed part of the rolling element 11). The orientation of the tangential vector component 20 results from the tangent to the force point of application of the intermediate elements 8, 9, 10 at the radius of the circle 53 in the circumferential direction 22, which lies on the circle. Further, as shown in FIG. 4, the first force 27, the second force 29, and the resultant forces 54, 55 are required to form a self-canceling force polygon. For this purpose, the first force direction 28, the second force direction 30 and the resultant force directions 56, 57 of the two rolling bodies 11, 12 must be present as shown. From the position shown, both the first energy storage element 17 (see fig. 1) and the second energy storage element 18 (see fig. 1) are more strongly tensioned, as a result of which an increased preload is exerted on the intermediate elements 8, 9, 10. The stronger tensioning is in this embodiment due to the radially inward movement of the intermediate elements 8, 9, 10, so that the energy storage elements 17, 18, 19 are compressed with the radially inward movement and in the manner of a screw clamp between the adjoining intermediate elements 8, 9, 10. The intermediate elements 8, 9, 10 are thus moved such that the distance between the intermediate elements 8, 9, 10 along the spring axes 31, 32, 33 of the energy storage elements 17, 18, 19 is shortened relative to the rest position if an increased stiffness is desired at higher torques (see fig. 5 to 8). In order to properly orient the pressure lines 49, 50, i.e. the lines of action of the resultant forces 54, 55 on the rolling bodies 11, 12, it is therefore necessary for the pressure lines 49, 50 to be always perpendicular to the transmission tracks 13, 14, in this case to the first transmission track 24 corresponding to the drag torque 45, which pressure lines intersect the rolling axes of the corresponding rolling bodies 11, 12 and the torque compensation point 48. The respective magnitudes of the resultant forces 54, 55 and the resultant force directions 56, 57 are inherently derived from the applied first force 27 and second force 29.

In fig. 5 to 8, moment-torsion angle diagrams are shown, in which the moment axis 58 forms the ordinate and the torsion angle axis 59 forms the abscissa. In this embodiment, the traction torque curve with positive torque and torsion angle is shown on the right side of the ordinate and the propulsion torque curve with negative torque and torsion angle is shown on the left side of the ordinate.

Fig. 5 shows a first transmission curve 24 corresponding to the traction torque pair 23 and a second transmission curve 26 corresponding to the propulsion torque pair 25 in two-stage increments, so that a flat curve rise occurs when the torque value is small and a steep curve rise occurs when the torque value is large.

Fig. 6 shows a two-stage progression variant, in which a steep curve rise occurs when the torque value is small, and a flat curve rise occurs when the torque value is large.

Fig. 7 shows a variant in which the increasing curve and the decreasing curve alternate and in which a comparison of a rigid system with steep curve trend shown in solid line versus a system with flat curve trend shown in dashed line is shown in fig. 8.

For the embodiment of fig. 1 and 2 without additional guidance of the intermediate elements 8, 9, 10, such transmission curves 24, 26 obey the conditions of torque and force balancing as illustrated in fig. 3 and 4. The illustrated transmission curves 24, 26 are thus implemented in superposition with the requirements for the transmission tracks 13, 14 according to the description of fig. 1 (and fig. 2). Furthermore, in one embodiment, in the rest position the force 25 or stiffness of the first energy storage element 17 is different from the second energy storage element 18 and is not implemented symmetrically as illustrated in fig. 1 and 2. This is also noted for superimposing to achieve the desired transmission curves 24, 26.

With the torsional vibration damper 5 proposed here, a low-cost and effective influence on the natural frequency can be achieved with a small number of components.

Fig. 9 shows a belt pulley decoupler 1 with a torsional vibration damper 5, for example according to fig. 1, in a simplified section through a first intermediate element 8, for example (see fig. 1 and corresponding description). The input side 6 is formed here (optionally) in one piece with a shaft connection 60, which is shown here (optionally) as being connected to a drive shaft 36, for example a crankshaft, by means of a shaft screw 61. The output side 7 is formed here (optionally) in one piece with a pulley 35, 38, which forms a respective belt receptacle for a belt 41, which is embodied here (optionally) as a V-belt, on the radially outer side. The drag torque 45 about the common rotational axis 2, which is shown here as the output torque of the drive shaft 36, is guided from the shaft connection 60 into the belt pulleys 35, 38 solely by means of the torsional vibration damper 5.

The drag torque 45 is thus transmitted from the input side 6 to the first rolling bodies 11, so that they roll on the input side 6, here on the first counter rail 15 arranged radially outside the input side 6. This rolling movement is in turn transmitted to the intermediate element 8, here to a (complementary) first drive track 13 arranged radially inside the intermediate element 8. The stepped embodiment of the first rolling element 12 (and of the second rolling element 12) is optional, but a sufficient axial positioning of the relevant rolling elements 11, 12 is advantageous. The traction torque 45 is transmitted from the intermediate element 8 to the output side 7 by means of the second rolling elements 12. In contrast, there, the movement of the intermediate element 8 forces the second rolling bodies 12 to roll on the second drive track 14, which in turn requires the second rolling bodies 12 to roll on the (complementary) second counter track 16 of the output side 7. The second drive track 14 of the intermediate element 8 is arranged here (optionally) radially inside, while the second counter track 16 of the output side 7 is arranged (correspondingly optionally) radially outside. For a better understanding of fig. 9 only, it should be noted that the (rectangular in this illustration) sections of the respective components 8, 35, 60 are radially aligned with the tracks 13, 14 of the rolling bodies 11, 12, respectively; 15. 16 are opposite. When the driving torque 46 is transmitted from the belt 41 to the drive shaft 36, the rolling bodies 11, 12 are forced to move in opposite directions by means of the tracks 13, 14, 15, 16. But the rolling of the rolling bodies 11, 12 on the tracks 13, 14, 15, 16 is suppressed by the forces 27, 29 of the energy storage element 18 (here the second energy storage element 18: the first energy storage element 17 in active engagement is not shown, whereas the third energy storage element 19 shown is not in direct active engagement with the first intermediate element 8 shown). The energy storage element 18 is here (optionally) embodied as a helical compression spring. Thus, although a large torque forces only a relatively small torsion angle between the input side 6 and the output side 7 due to the high (spring) stiffness of the energy storage elements 17, 18, 19, the oscillating movement of the rolling bodies 11, 12 only resists the small (spring) stiffness due to the reduction rolling transmission formed by the rails 13, 14, 15, 16. Thus, a large torque can be transmitted by using energy storage elements 17, 18, 19 with a high (spring) stiffness. At the same time, a desired reduction of the (system) resonance frequency can be achieved due to the softness (low stiffness) of the movement of the rolling elements 11, 12.

Fig. 10 schematically shows a motor vehicle 42 in a top view. The motor vehicle 42 has a left drive wheel 43 and a right drive wheel 44, which are provided for propelling the motor vehicle 42 in a main driving direction (to the left as shown along the longitudinal axis 63). The torque required for this is provided by the drive machine 37, here (optionally) the internal combustion engine 4, on demand by means of the drive shaft 36 of the drive train 34 shown. Furthermore, power should be supplied to consumers, for example, batteries or air conditioning compressors, by means of the drive machine 37. For this purpose, a belt drive 3 is provided, which connects the drive shaft 36 to a rotor shaft 39 of an auxiliary device 40 (for example a motor generator) in a torque-transmitting manner. The belt drive 3 comprises a first belt pulley 35 on a drive shaft 36 and a second belt pulley 38 on a rotor shaft 39, which are connected to each other in a torque-transmitting manner by means of a belt 41. Here, only the first pulley 35 (optionally) comprises the pulley decoupler 1.

With the belt pulley decoupler presented herein, interfering rotational speed fluctuations and belt movement and noise can be reduced and the service life of the belt drive assembly can be extended.

List of reference numerals

1. Belt pulley decoupler

2. Axis of rotation

3. Belt transmission mechanism

4. Internal combustion engine

5. Torsional vibration damper

6. Input side

7. Output side

8. First intermediate element

9. Second intermediate element

10. Third intermediate element

11. First rolling element

12. Second rolling element

13. First transmission rail

14. Second transmission rail

15. First corresponding track

16. Second corresponding track

17. First energy storage element

18. Second energy storage element

19. Third energy storage element

20. Tangential vector component

21. Radial vector component

22. In the circumferential direction

23. Traction moment pair

24. First transmission curve

25. Thrust moment pair

26. Second transmission curve

27. First force

28. Direction of first force

29. Second force

30. Second force direction

31. First spring axis

32. Second spring axis

33. Third spring axis

34. Drive train

35. First belt pulley

36. Driving shaft

37. Driving machine

38. Second belt pulley

39. Rotor shaft

40. Auxiliary device

41. Belt with belt body

42. Motor vehicle

43. Left driving wheel

44. Right driving wheel

45. Traction moment

46. Thrust moment

47. Stationary wire

48. Moment balance point

49. First pressure line

50. Second pressure line

51. First line of action

52. First line of action

53. Circle of force application points

54. First resultant force

55. Second resultant force

56. First resultant force direction

57. Second resultant force direction

58. Moment axis

59. Axis of torsion angle

60. Shaft connecting part

61. Shaft tightening part

62. A longitudinal axis.

Claims

1. A belt pulley decoupler (1) having a rotational axis (2) for a belt drive (3) of an internal combustion engine (4), wherein the belt pulley decoupler (1) comprises a torsional vibration damper (5) having at least the following components:

-an input side (6) for receiving torque;

-an output side (7) for outputting torque;

-at least one intermediate element (8, 9, 10) in a torque transmitting connection between the input side (6) and the output side (7);

a first rolling element (11) and a second rolling element (12) of each intermediate element (8, 9, 10),

Wherein the at least one intermediate element (8, 9, 10) has a first transmission track (13) for the rolling of the first rolling bodies (11) and a second transmission track (14) for the rolling of the second rolling bodies (12), wherein the input side (6) has a first counter track (15) complementary to the first transmission track (13) and the output side (7) has a second counter track (16) complementary to the second transmission track (14), wherein the first rolling bodies (11) are guided in a rolling manner between the first transmission track (13) and the first counter track (15) and the second rolling bodies (12) are guided in a rolling manner between the second transmission track (14) and the second counter track (16). And

At least one energy storage element (17, 18, 19) by means of which an intermediate element (8, 9, 10) corresponding to the energy storage element (17, 18, 19) is supported in a vibratable manner,

It is characterized in that the method comprises the steps of,

The energy storage elements (17, 18, 19) are arranged with vector components (20) acting on the corresponding intermediate elements (8, 9, 10) in a circumferential direction (22); exactly three intermediate elements (8, 9, 10) and exactly three energy storage elements (17, 18, 19) are provided, wherein a first intermediate element (8) and a second intermediate element (9) are supported by means of the first energy storage element (17), a second intermediate element (9) and a third intermediate element (10) are supported by means of the second energy storage element (18), and the first intermediate element (8) and the third intermediate element (10) are supported by means of the third energy storage element (19); the two rolling bodies (11, 12) are arranged at a distance from each other in the radial direction and/or at a distance from each other in the circumferential direction (22).

2. A belt pulley decoupler (1) having a rotational axis (2) for a belt drive (3) of an internal combustion engine (4), wherein the belt pulley decoupler (1) comprises a torsional vibration damper (5) having at least the following components:

-an input side (6) for receiving torque;

-an output side (7) for outputting torque;

-at least two intermediate elements (8, 9, 10) in a torque transmitting connection between the input side (6) and the output side (7);

Wherein the intermediate elements (8, 9, 10) each have a first transmission track (13) for the rolling of the first rolling bodies (11) and a second transmission track (14) for the rolling of the second rolling bodies (12), wherein the input side (6) has a first counter track (15) complementary to the first transmission track (13) and the output side (7) has a second counter track (16) complementary to the second transmission track (14), wherein the first rolling bodies (11) are guided in a rolling manner between the first transmission track (13) and the first counter track (15) and the second rolling bodies (12) are guided in a rolling manner between the second transmission track (14) and the second counter track (16). And

A plurality of energy storage elements (17, 18, 19) corresponding to the number of intermediate elements (8, 9, 10), by means of which the respective intermediate element (8, 9, 10) corresponding to the energy storage element (17, 18, 19) is supported in a vibratable manner,

Wherein each of the intermediate elements (8, 9, 10) is supported on the respective at least one adjacent intermediate element (8, 9, 10) by means of a corresponding energy storage element (17, 18, 19),

It is characterized in that the method comprises the steps of,

For each intermediate element (8, 9, 10), only the first rolling element (11) and the second rolling element (12) are provided as rolling elements; exactly three intermediate elements (8, 9, 10) and exactly three energy storage elements (17, 18, 19) are provided, wherein a first intermediate element (8) and a second intermediate element (9) are supported by means of the first energy storage element (17), a second intermediate element (9) and a third intermediate element (10) are supported by means of the second energy storage element (18), and the first intermediate element (8) and the third intermediate element (10) are supported by means of the third energy storage element (19); the two rolling bodies (11, 12) are arranged at a distance from each other in the radial direction and/or at a distance from each other in the circumferential direction (22).

3. Belt pulley decoupler (1) according to claim 1 or 2, wherein the at least one intermediate element (8, 9, 10) is supported solely by means of the at least one corresponding energy storage element (17, 18, 19) and by means of the rolling bodies (11, 12).

4. Belt pulley decoupler (1) according to claim 1 or 2, wherein the drive track (13, 14) and the respective complementary counterpart track (15, 16) each comprise a traction torque pair (23) with a first drive curve (24) and a driving torque pair (25) with a second drive curve (26), wherein the traction torque pair (23) is provided for transmitting torque from the input side (6) to the output side (7), wherein the driving torque pair (25) is provided for transmitting torque from the output side (7) to the input side (6),

Wherein the first transmission curve (24) and the second transmission curve (26) have transmission directions which are different from each other at least in some regions.

5. Belt pulley decoupler (1) according to claim 1 or 2, wherein the at least one intermediate element (8, 9, 10) is preloaded by means of two opposing energy storage elements (17, 18),

Wherein preferably the first energy storage element (17) applies a first force (27) and a first force direction (28) to the corresponding intermediate element (8, 9) and the second energy storage element (18) applies a second force (29) and a second force direction (30) to the corresponding intermediate element (8, 10),

Wherein the first force (27) and the second force (29) differ from each other in a rest position and/or the first force direction (28) and the second force direction (30) differ from each other in a rest position.

6. Belt pulley decoupler (1) according to claim 1 or 2, wherein the at least one energy storage element (17, 18, 19) is a helical compression spring having a straight spring axis (31, 32, 33).

7. A belt drive (3) for a drive train (34) having at least the following components:

-a first pulley (35) for connection with a drive shaft (36) of a drive machine (37);

-a second pulley (38) for connection with a rotor shaft (39) of an auxiliary device (40); and

A belt (41) connecting the first pulley (35) and the second pulley (38) in a torque-transmitting manner,

Wherein the first pulley (35) and/or the second pulley (38) comprises a pulley decoupler (1) according to any one of the preceding claims.

8. A drive train (34) having at least the following components:

-a drive machine (37) having a drive shaft (36);

-an auxiliary device (40) having a rotor shaft (39); and

-A belt drive (3) according to claim 7, by means of which the drive machine (36) and the auxiliary device (40) are connected to each other in a torque-transmitting manner.