DE102018113585B4 - Torsional vibration damper - Google Patents

Abstract

Torsional vibration damper, in particular dual-mass flywheel, pulley decoupler or disk damper, for damping torsional vibrations in a drive train of a motor vehicle, with a primary mass (12) forming a circumferential receiving space (14), one via an energy storage element (16), in particular an arc spring, relative to the primary mass (12) limited rotatable secondary mass (20) and an additional damper (28) connected in parallel to the energy storage element (16) for damping torsional vibrations in a drive train of a motor vehicle, the additional damper (28) having an additional energy storage element (34), in particular designed as a compression coil spring or bow spring, the Additional damper (28), a first guide shell (30) connected to the primary mass (12) for partially receiving the additional energy storage element (34) and a second guide shell connected to the secondary mass (20), in particular to the output flange (18) of the secondary mass (20). (32) for partially receiving the additional energy storage element (34), wherein the first guide shell (30) and the second guide shell (32) are designed to abut tangentially on the additional energy storage element (34), characterized in that the first guide shell (30) and / or the second guide shell (32) is designed essentially as a half-shell with essentially semicircular end faces.

Description

The invention relates to a torsional vibration damper, in particular a dual-mass flywheel, pulley decoupler or disc damper, with the aid of which torsional vibrations in a drive train of a motor vehicle can be dampened.

For example from DE 10 2015 221 022 A1 is a torsional vibration damper designed as a dual-mass flywheel with a primary mass and a secondary mass that can be rotated to a limited extent with the primary mass via an arc spring, the secondary mass having an output flange projecting into a receiving channel formed by the primary mass for receiving the arc spring.

From the publication DE 10 2015 204 687 A1 A torsional vibration damper with a switchable, bilaterally effective freewheel is known.

The WO 2006/ 053 525 A1 discloses a torsional vibration damper with an input part and an output part which is rotatable relative to the input part against the resistance of a first energy storage device and a second energy storage device which is connected in parallel to the first energy storage device. In order to isolate vibration-related irregularities that occur during operation, the second energy storage device comprises a plurality of energy storage elements which are articulated to the output part at various points over the circumference.

The DE 10 2016 220 570 A1 shows a dual-mass flywheel for damping torsional vibrations of a drive shaft of a motor vehicle engine with a primary mass that can be coupled to the drive shaft to introduce a torque, a secondary mass that can be rotated relative to the primary mass to dissipate the torque, an energy storage element that can be coupled to the primary mass and the secondary mass for transmitting torque between the primary mass and the secondary mass.

From the disclosure document DE 38 02 106 A1 A split flywheel is known, the flywheel elements of which are elastically coupled by means of two spring groups connected in parallel, one spring group working with play and essentially only becoming effective when larger torques are transmitted

The DE 10 2010 053 256 A1 discloses a torsional vibration damper with an input part and an output part that can be rotated to a limited extent relative to this, as well as two damper stages effective between them, at least a first damper stage being designed without a friction device and a second damper stage having a low friction effect.

From the US 2002 / 0 011 229 A1 A vibration decoupling system is known, comprising an elastic element and a rotating element which is driven by the elastic element from a rotating shaft of the motor.

The DE 10 2015 203 106 A1 shows a torsional vibration damper, in particular for an application with a double clutch, with an input part and with an output part, with a spring damper device, the output part being rotatable relative to the input part against the restoring force of the spring damper device, the spring damper device having a first spring arrangement with first force accumulators and a second spring arrangement with second energy accumulators, the two spring assemblies with their energy accumulators being arranged adjacent to one another in the axial direction. The output part has a first flange and a second flange, which are arranged adjacent to one another and the first flange is supported on the first energy accumulators and the second flange is supported on the second energy accumulators, a centrifugal force pendulum device being arranged between the two flanges.

The publication DE 42 25 304 A1 relates to a disc-shaped component for a belt drive for driving auxiliary units of an internal combustion engine, which can be fastened on a shaft of the internal combustion engine, the disc-shaped component containing a damping device which is provided between an input part which can be fastened to the shaft and an output part which can be rotated relative thereto, and wherein Input and output parts can be rotated relative to each other via a rolling bearing.

There is a constant need for a torsional vibration damper in the drive train of a motor vehicle to provide the softest possible spring characteristic for a high level of comfort and to provide the highest possible blocking torque at the maximum possible angle of rotation for a high effective range.

It is the object of the invention to show measures that enable a torsional vibration damper with a soft spring characteristic and a high blocking moment at the maximum possible angle of rotation.

The problem is solved according to the invention by a torsional vibration damper the features of claim 1. Preferred embodiments of the invention are specified in the subclaims and the following description, which can each represent an aspect of the invention individually or in combination.

According to the invention, a torsional vibration damper, in particular a dual-mass flywheel, pulley decoupler or disk damper, is provided for damping torsional vibrations in a drive train of a motor vehicle with a primary mass forming a circumferential receiving channel, a secondary mass which can be rotated to a limited extent relative to the primary mass via an energy storage element, in particular an arc spring, and a secondary mass which is connected in parallel to the energy storage element Additional damper for damping torsional vibrations in a drive train of a motor vehicle.

The additional damper has an additional energy storage element, in particular designed as a compression coil spring or bow spring, the additional damper having a first guide shell connected to the primary mass for partially receiving the additional energy storage element and a second guide shell connected to the secondary mass, in particular to the output flange of the secondary mass, for partially receiving it of the additional energy storage element, wherein the first guide shell and the second guide shell are designed to abut tangentially on the additional energy storage element. Due to the relative rotation of the secondary mass to the primary mass, the guide shells can also carry out a relative rotation and strike tangentially on the additional energy storage element. As a result, a torque can be exchanged between the primary mass and the secondary mass via a torque flow running parallel to the energy storage element. The guide shells can each form a stop acting in a tangential direction, in particular on their end faces, between which the additional energy storage element is accommodated, so that a torque can be transmitted in each case during a relative movement in different circumferential directions. In particular, the guide shell has not only a tangentially acting stop, but also a guide surface pointing in the radial direction and/or in the axial direction, on which the additional energy storage element can slide and is guided. The guide shells can prevent the additional energy storage element from buckling under load. Additionally or alternatively, guidance of the additional energy storage element can also be realized through the primary mass and/or the output flange, for example by forming a recess with a part-circular cross-section for receiving the additional energy storage element in the primary mass and/or the output flange. The guide shell can thereby be formed in one piece with the primary mass or with the output flange.

In addition, the first guide shell and/or the second guide shell is designed essentially as a half-shell with essentially semicircular end faces. The guide shells can thereby have an inner contour adapted to an outer contour of the additional energy storage element, in particular designed as an optionally curved helical spring. The guide shells can be positioned at a distance from one another over the smallest possible air gap in order to avoid a blocking impact. At the same time, almost the entire additional energy storage element can be covered by the guide shells. The semicircular end faces at the ends of the inner contour of the respective guide shell facing the additional energy storage element can form a significantly larger contact surface with the additional energy storage element compared to a narrow side of a disk, whereby a correspondingly lower surface pressure can be achieved.

The parallel connection of the energy storage element and the additional damper can result in a spring characteristic that is stiffer compared to the spring characteristic of the energy storage element alone or the spring characteristic of the additional damper alone. By providing a clearance angle for the energy storage element and/or for the additional damper, a rotation angle range of the relative rotation of the secondary mass relative to the primary mass can also be specified in which only the energy storage element or only the additional damper is effective. In this rotation angle range, a damper stage with a soft spring characteristic is formed. If there is a sufficiently strong relative rotation of the secondary mass to the primary mass, the intended clearance angle can be exceeded, so that a correspondingly stiff spring characteristic curve is effective above the clearance angle due to the parallel connection of the energy storage element and the additional damper. This means that the soft damper stage can be followed by a hard damper stage with a stiff spring characteristic. The soft damper level is perceived by a driver of the motor vehicle as particularly comfortable. The hard damping level can dampen a hard impact when the maximum possible rotation angle is reached. In addition, the maximum possible angle of rotation is only reached at a correspondingly higher block torque, so that vibration damping can occur over a correspondingly larger torque range. By connecting the additional damper in parallel Furthermore, a harder damping level can easily be added, so that a torsional vibration damper with a soft spring characteristic and a high blocking moment at the maximum possible angle of rotation is possible.

The additional damper can be positioned slightly spaced from the energy storage element so that free installation space can be used for the additional damper. The installation space requirement can thereby be kept low. It also makes it easier to operate the additional damper in a rotation angle range that is different from the energy storage element and to realize an overall spring characteristic curve with ranges of different spring constants. If the secondary mass is rotated from a neutral zero position relative to the primary mass in a first circumferential direction or a second circumferential direction opposite to the first circumferential direction, no damping can initially be provided, for example as a result of a clearance angle provided for the energy storage and the additional damper, so that particularly high frequencies are involved low amplitudes can be filtered out in the manner of a low-pass filter. However, it is also possible that initially only the energy storage element or only the additional damper is effective at the start of a relative rotation.

The primary mass and the secondary mass, which is rotatably coupled to the primary mass in a limited manner via the energy storage element, which is designed in particular as an arc spring, can form a spring-mass system which can dampen rotational irregularities in the speed and torque of the drive power generated by a motor vehicle engine in a certain frequency range. Here, the mass moment of inertia of the primary mass and/or the secondary mass as well as the spring characteristic of the energy storage element can be selected such that vibrations in the frequency range of the dominant engine orders of the motor vehicle engine can be dampened. The mass moment of inertia of the primary mass and/or the secondary mass can be influenced in particular by an attached additional mass. The primary mass can have a disk to which a cover can be connected, whereby a substantially annular receiving space for the energy storage element can be limited. The primary mass can, for example, strike tangentially on the energy storage element via impressions projecting into the receiving space. An output flange of the secondary mass can protrude into the receiving space and can abut tangentially on the opposite end of the energy storage element. If the torsional vibration damper is part of a dual-mass flywheel, the primary mass can have a flywheel that can be coupled to a drive shaft of a motor vehicle engine. If the torsional vibration damper as a pulley decoupler is part of a pulley arrangement for driving auxiliary units of a motor vehicle with the aid of a traction device, the primary mass can form a pulley, on the radially outer surface of which the traction device, in particular a V-belt, can act to transmit torque.

The energy storage element can be designed in multiple stages, for example by providing a further arc spring within an arc spring. The outer arc spring and the inner arc spring can be effective via different clearance angles and/or have different spring characteristics. Additionally or alternatively, the additional damper can have an additional energy storage element, which can be designed in one or more stages. The number of different damping areas for the torsional vibration damper can thereby be increased. The overall spring characteristic of the torsional vibration damper can have several sub-areas with different spring constants, so that the torsional vibration damper can be individually adapted to different application situations with different damping requirements.

In particular, the secondary mass has an output flange projecting into the receiving space for tangential abutment on the energy storage element, the additional damper being coupled to the primary mass and to the output flange. The output flange of the secondary mass generally runs essentially parallel to a disk-shaped region of the primary mass, via which the primary mass can be attached, for example, to a drive shaft of a motor vehicle engine. The additional damper can thereby be easily positioned in an axial gap between the disk-shaped area of the primary mass and the output flange. Here, the additional damper can be arranged in particular in a receiving space formed by the primary mass for receiving the energy storage element, where the additional damper can be protected from external influences. The additional damper can be arranged offset from the energy storage element in the radial direction and in the axial direction. The installation space requirement can thereby be kept low.

Particularly preferably, the first guide shell and the second guide shell are designed to be relatively rotatable and movable past one another. This safely prevents the guide shells from hitting each other. Instead is enables the additional energy storage element to be maximally compressed between the guide shells up to the block state. For this purpose, the additional energy storage element can protrude partly into the area of the first guide shell and another part into the area of the second guide shell in order to form a tangential stop surface for the respective guide shell.

Preferably, the first guide shell and the second guide shell are designed to be open in the axial direction, with the first guide shell and the second guide shell in particular being designed as identical parts. The guide shells can therefore rest against the primary mass or the secondary mass with an axial rear side, which enables good force support and secure fastening. Because the guide shells are not opened in the radial direction but in the axial direction, centrifugal forces acting on the additional energy storage element can be supported by both guide shells and not just by one guide shell. This avoids force peaks within a guide shell. Instead, forces that occur can be distributed more easily between the guide shells.

Particularly preferably, the additional damper, in particular the guide shells, is connected to the primary mass and/or to the secondary mass, in particular to the output flange of the secondary mass, by pressing, riveting and/or pinning. The elastic and/or plastic deformation at the connection point results in a connection with high strength that can also withstand high shear forces.

In particular, the energy storage element is designed to be tangentially abuttable to the primary mass and/or the secondary mass via a clearance angle in the circumferential direction, with the additional damper being designed to be effective at least in a large part of the clearance angle of the energy storage element. In a relative rotation angle range of the secondary mass to the primary mass, in which the energy storage element is not yet effective due to the provided clearance angle, only the additional damper can possibly also be effective after a clearance angle has been passed. In this rotation angle range, a soft damper stage can therefore be formed, which is followed by a harder damper stage with a stiffer overall spring constant after the clearance angle provided for the energy storage element has been covered by the parallel connection of the additional damper and the then effective energy storage element.

Preferably, the secondary mass has an output flange projecting into the receiving space for tangential abutment on the energy storage element, the output flange having a transmission flange which rests tangentially on the energy storage element and a connection flange coupled to the transmission flange in a torque-transferable manner, wherein between the transmission flange and the connection flange, in particular via a toothing , a clearance angle is formed in the circumferential direction and can be coupled either to the connection flange or to the transmission flange. This means that the additional damper can be connected via a clearance angle. Depending on whether the additional damper is connected to the connection flange or to the transmission flange, the time at which the clearance angle formed between the connection flange and the transmission flange should be effective can be adjusted, whereby the overall spring characteristic can be designed accordingly. In particular, it is provided that the additional damper only becomes effective when the clearance angle provided for the additional damper is swept during a relative rotation of the secondary mass to the primary mass. This makes it possible, for example, to design a low-pass filter in which high frequencies with low amplitudes can be filtered out. However, the clearance angle is not formed within the additional damper but rather within the at least two-part output flange. A clearance angle provided in the radius area of the additional damper can thereby be avoided, so that more installation space can be provided in the circumferential direction for an additional energy storage element. The additional energy storage element of the additional damper can thereby be in permanent contact with tangentially effective stops, in particular with prestress, so that a hard impact of the respective stop on the additional energy storage element after overcoming a free space can be avoided. By pre-tensioning the additional energy storage element, it can be ensured that the additional energy storage element does not lift off the stops even under the forces that occur during operation. It is also possible to increase the extent of the additional energy storage element in the circumferential direction, whereby a softer spring characteristic can be achieved.

Particularly preferably, a friction device is provided between the transmission flange and the connecting flange to provide damping against a resonance-related build-up of torsional vibrations. Due to the deliberate friction, the spring-mass system of the torsional vibration damper can be sufficiently damped in order to avoid excessive deflections in the resonance range. For this purpose, the relative movements of the transmission flange to the connecting flange can be used to produce relative movements that involve friction. The friction device can have a first friction partner fastened to the transmission flange and a second friction partner fastened to the connecting flange, which are pressed against each other with friction, for example with the aid of a spring. The friction partners can be represented, for example, by axial friction rings.

In particular, the additional damper is provided within the receiving space. The additional damper can thereby be positioned over a comparatively large radius range, which enables a correspondingly large extension in the circumferential direction for the additional damper. This allows the additional damper to have a correspondingly soft spring characteristic.

The invention further relates to a pulley arrangement for driving auxiliary units of a motor vehicle with the aid of a traction device with a pulley for driving the traction device, a hub that can be coupled to a drive shaft of a motor vehicle engine for introducing a torque and a torsional vibration damper, which can be designed and further developed as described above , where the pulley is part of the primary mass and the hub is part of the secondary mass of the torsional vibration damper. By connecting the additional damper in parallel, a harder damping level can easily be added, so that a torsional vibration damper with a soft spring characteristic and a high blocking torque at the maximum possible angle of rotation is possible.

• 1: eine schematische geschnittene Seitenansicht eines Drehschwingungsdämpfers.

The invention is explained below by way of example with reference to the accompanying drawing using a preferred exemplary embodiment, whereby the features shown below can represent an aspect of the invention both individually and in combination. It shows:

• 1 : a schematic sectional side view of a torsional vibration damper.

The in 1 Using the example of a pulley decoupler in a pulley arrangement for driving auxiliary units of a motor vehicle with the aid of a traction device, the torsional vibration damper 10 shown has a primary mass 12 designed as a pulley, which delimits an annular receiving space 14 for an energy storage element 16 designed as a bow spring. An output flange 18 of a secondary mass 20 projects into the receiving space 14 from the radial inside. The secondary mass 20 has, for example, a two-part hub 22 with which the output flange 18 is fastened. In addition, a rubber absorber 24 is attached to the hub 22. A fastening means 26 designed as a dowel pin for fastening the rubber absorber 24 also fastens the output flange 18, which runs centrally to the energy storage element 16, to the hub 22 and holds the multi-part hub 22 together. The fastening means 26 can be designed, for example, as a screw connection, pinning and/or a press fit. By designing the fastening means 26 as a dowel pin, the rubber absorber 24 can easily be positioned on the hub 22.

An additional damper 28 connected in parallel to the energy storage element 16 is connected to the primary mass 12 and to the output flange 18. For this purpose, the additional damper 28 has a first guide shell 30 connected to the primary mass 12 and a second guide shell 32 connected to the output flange 18 and spaced from the first guide shell 30 via an air gap, each of which accommodates one half of an additional energy storage element 34 designed as a helical compression spring. The guide shells 30, 32, which are open in the axial direction, can abut tangentially on the inside of their end faces on the additional energy storage element 34 in order to transmit a torque. To form a two-stage damping characteristic with a soft first damper stage and a hard second damper stage, a clearance angle can be provided for the energy storage element 16 and / or for the additional damper 28, so that in a rotation angle range when the secondary mass 20 rotates relative to the primary mass 12, initially only the energy storage element 16 or only the additional damper 28 and in a rotation angle range up to the maximum possible rotation angle both the energy storage element 16 and the additional damper 28 are effective. The output flange 18 can be designed in two parts, in that the output flange 18 has a transmission flange which rests tangentially on the energy storage element 16 and a connection flange connected to the hub 22, which is coupled to the transmission flange in a torque-transferable manner via a clearance angle. If the second guide shell 32 is attached to the connecting flange, a clearance angle for the additional damper 28 can be formed outside the additional damper 28.

Reference symbol list

10

Torsional vibration damper

12

Primary mass

14

Recording channel

16

Energy storage element

18

Output flange

20

secondary mass

22

hub

24

Rubber eradicator

26

Fasteners

28

Additional damper

30

first guide shell

32

second guide shell

34

Additional energy storage element

Claims (8)

Torsional vibration damper, in particular dual-mass flywheel, pulley decoupler or disk damper, for damping torsional vibrations in a drive train of a motor vehicle, with a primary mass (12) forming a circumferential receiving space (14), one via an energy storage element (16), in particular an arc spring, relative to the primary mass (12 ) limited rotatable secondary mass (20) and an additional damper (28) connected in parallel to the energy storage element (16) for damping torsional vibrations in a drive train of a motor vehicle, the additional damper (28) having an additional energy storage element (34), in particular designed as a compression coil spring or bow spring, wherein the additional damper (28) has a first guide shell (30) connected to the primary mass (12) for partially receiving the additional energy storage element (34) and one connected to the secondary mass (20), in particular to the output flange (18) of the secondary mass (20). second guide shell (32) for partially receiving the additional energy storage element (34), wherein the first guide shell (30) and the second guide shell (32) are designed to abut tangentially on the additional energy storage element (34), characterized in that the first guide shell (30 ) and / or the second guide shell (32) is designed essentially as a half-shell with essentially semicircular end faces. Torsional vibration damper Claim 1 , characterized in that the secondary mass (20) has an output flange (18) projecting into the receiving space (14) for tangential abutment on the energy storage element (16), the additional damper (28) being connected to the primary mass (12) and to the output flange ( 18) is coupled. Torsional vibration damper Claim 1 or 2 , characterized in that the first guide shell (30) and the second guide shell (32) are designed to be relatively rotatable and movable past each other. Torsional vibration damper according to one of the Claims 1 until 3 , characterized in that the first guide shell (30) and the second guide shell (32) are designed to be open in the axial direction, in particular the first guide shell (30) and the second guide shell (32) being designed as identical parts. Torsional vibration damper according to one of the Claims 1 until 4 , characterized in that the additional damper (28), in particular the guide shells (30, 32), with the primary mass (12) and / or with the secondary mass (20), in particular with the output flange (18) of the secondary mass (20). Pressing, riveting and/or pinning is connected. Torsional vibration damper according to one of the Claims 1 until 5 , characterized in that the energy storage element (16) is designed to be tangentially stopable on the primary mass (12) and/or on the secondary mass (20) via a clearance angle in the circumferential direction, the additional damper (28) being designed at least in a large part of the clearance angle of the Energy storage element (16) to be effective. Torsional vibration damper according to one of the Claims 1 until 6 , characterized in that the secondary mass (20) has an output flange (18) projecting into the receiving space (14) for tangential abutment on the energy storage element (16), the output flange (18) having a transmission flange which rests tangentially on the energy storage element (16) and has a torque-transferable connecting flange coupled to the transmission flange, wherein a clearance angle is formed in the circumferential direction between the transmission flange and the connecting flange, in particular via a toothing, and the additional damper (28) can be coupled to the primary mass (12) and either to the connecting flange or to the transmission flange is. Pulley arrangement for driving auxiliary units of a motor vehicle with the aid of a traction means, with a pulley for driving the traction means, a hub (22) which can be coupled to a drive shaft of a motor vehicle engine for introducing a torque and a torsional vibration damper according to one of the Claims 1 until 7 , where the pulley is part of the primary mass (12) and the hub (22) is part of the secondary mass (20) of the torsional vibration damper (10).

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