Pulley decoupler having a centrifugal pendulum device with a first friction device

Abstract

A pulley decoupler for an accessory drive comprises input and output parts. The output part and the input part are rotatable about a common axis of rotation and are rotatable to a limited extent relative to one another. A centrifugal pendulum device is provided for damping torsional vibrations with a centrifugal pendulum flange that can be rotated about the axis of rotation and has at least one pendulum mass displaceable under centrifugal force relative to the centrifugal pendulum flange. The at least one pendulum mass is acted on by a friction force generated by a first friction device having a first spring and at least one first friction element.

Claims

1. A pulley decoupler for an accessory drive, comprising: an input part; an output part, the output part and the input part being rotatable about a common axis of rotation and being rotatable to a limited extent relative to one another; and a centrifugal pendulum device for damping torsional vibrations with a centrifugal pendulum flange which can be rotated about the axis of rotation and which has at least one pendulum mass which is displaceable under centrifugal force relative to the centrifugal pendulum flange, wherein the at least one pendulum mass is acted on by a friction force generated by a first friction device having a first spring and at least one first friction element.

2. The pulley decoupler according to claim 1, wherein the first spring is supported on a cover of a pulley of the output part.

3. The pulley decoupler according to claim 2, wherein the first friction element is disposed in a receptacle of the cover and is guided parallel to the axis of rotation.

4. The pulley decoupler according to claim 1, wherein at least a section friction element is arranged between the at least one pendulum mass and the centrifugal pendulum flange.

5. The pulley decoupler according to claim 1, wherein the centrifugal pendulum flange is arranged between a spring flange of the input part and a hub of the pulley decoupler.

6. The pulley decoupler according to claim 1, wherein the centrifugal pendulum device is at least partially covered by a first cover cap which is fastened to a pulley of the output part.

7. The pulley decoupler according to claim 1, wherein the output part has a pulley which at least partially surrounds the centrifugal pendulum device.

8. The pulley decoupler according to claim 6, wherein the at least one pendulum mass is arranged in a centrifugal pendulum space of the centrifugal pendulum device, wherein the centrifugal pendulum space is at least partially closed by a second cover cap.

9. The pulley decoupler according to claim 8, wherein the second cover cap is connected to a second friction device, so that the second cover cap generates an axial force on the pulley decoupler.

10. The pulley decoupler according to claim 8, wherein the second cover cap is designed as a plate spring, so that the second cover cap generates an axial force on the pulley decoupler.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The disclosure and the technical environment are explained in more detail below with reference to the figures. It should be pointed out that the figures show particularly preferred variants of the disclosure, but the disclosure is not restricted to them. Like components are provided with the same reference numerals in the figures. Exemplarily and schematically, they show:

[0028] FIG. 1: a first variant of a pulley decoupler; and

[0029] FIG. 2: a second variant of a pulley decoupler.

DETAILED DESCRIPTION

[0030] FIG. 1 shows a first variant of a pulley decoupler 1 in a longitudinal section. The pulley decoupler 1 has an input part 2 with a hub 16, a centrifugal pendulum flange 6, a centrifugal pendulum device 5 and a spring flange 15. The hub 16, the centrifugal pendulum flange 6 and the flange 15 are arranged for conjoint rotation and can be rotated together about an axis of rotation 4 by a motor vehicle drive motor, not shown here. The pulley decoupler 1 also has an output part 3 with a pulley 12. A traction means running surface 22 for a traction means, not shown here, is formed on an outer circumferential surface 23 of the pulley 12. Between the input part 2 and the output part 3, a damping device 28 is provided with a plurality of energy stores 30 distributed in a circumferential direction, the energy stores 30 here being designed in the form of arc springs. The energy stores 30 are supported on the one hand on the spring flange 15 and on the other hand on the pulley 12 or a cover 11 of the pulley 12, so that the input part 2 and the output part 3 can be rotated relative to one another to a limited extent against a spring force of the energy stores 30. The cover 11 is pressed into the pulley 12 so that it cannot rotate relative to the pulley 12.

[0031] Furthermore, the cover 11 has in a radial section a receptacle 13, in which a first friction element 10 of a first friction device 8 is guided parallel to the axis of rotation 4. The first friction device 8 also comprises a first spring 9, which is designed here in the form of an annular plate spring. The first spring 9 is supported on the radial section of the cover 11 and presses the first friction element 10 in an axial direction, i.e. parallel to the axis of rotation 4, against a first pendulum mass 7 which is displaceable under centrifugal force relative to the centrifugal pendulum flange 6. A second friction element 14 is arranged between the first pendulum mass 7 and the centrifugal pendulum flange 6. When the first pendulum mass 7 is displaced, the first friction device 8 thus generates a friction force by means of which movement of the first pendulum mass 7 is braked. Furthermore, a second pendulum mass 21 which is displaceable under centrifugal force relative to the centrifugal pendulum flange 6, is arranged on an opposite side of the centrifugal pendulum flange 6. The first pendulum mass 7, the second friction element 14 and the second pendulum mass 21 are held in a centrifugal pendulum space 18 by means of pendulum rollers 27 on the centrifugal pendulum flange 6. The centrifugal pendulum space 18 is partially limited by a first cover cap 17 pressed into the first pulley 12 and a second cover cap 19 pressed into the first cover cap 17. The second cover cap 19 is acted on by an axial force from a second friction device 20. For this purpose, the second friction device 20 has a second spring 26, which is designed here in the form of an annular plate spring and on the one hand is supported on a third friction element 24, which is held in the axial direction by a circumferential collar 29 of the hub 16, and on the other is supported on a fourth friction element 25 of the second cap 19.

[0032] FIG. 2 shows a second variant of a pulley decoupler 1 in a longitudinal section, which differs from the first variant of the pulley decoupler 1 shown in FIG. 1 only in that the second cover cap 19 pressed into the first cover cap 17 itself functions as a plate spring and when installed directly generates an axial force on the pulley decoupler 1 by pressing on the third friction element 24 of the hub 16.

[0033] With the present disclosure, a pulley decoupler may be operated at a particularly low noise level.

LIST OF REFERENCE NUMBERS

[0034] 1 pulley decoupler [0035] 2 input part [0036] 3 output part [0037] 4 axis of rotation [0038] 5 centrifugal pendulum device [0039] 6 centrifugal pendulum flange [0040] 7 first pendulum mass [0041] 8 first friction device [0042] 9 first spring [0043] 10 first friction element [0044] 11 cover [0045] 12 pulley [0046] 13 receptacle [0047] 14 second friction element [0048] 15 spring flange [0049] 16 hub [0050] 17 first cover cap [0051] 18 centrifugal pendulum space [0052] 19 second cover cap [0053] 20 second friction device [0054] 21 second pendulum mass [0055] 22 traction means surface [0056] 23 circumferential surface [0057] 24 third friction element [0058] 25 fourth friction element [0059] 26 second spring [0060] 27 pendulum roller [0061] 28 damping device [0062] 29 collar [0063] 30 energy storage