Abstract
A torsional vibration damper for a clutch disk within a drive train of a motor vehicle includes an input part arranged around an axis of rotation (d), a spring device with at least three spring elements, an output part, and torque-transmitting intermediate elements. The output part can be rotated relative to the input part about the axis of rotation (d) to a limited extent against the spring device. The torque-transmitting intermediate elements are arranged between the input part and the output part for forcible radial displacement by means of cam mechanisms when the input part rotates relative to the output part. The spring device is arranged between the torque-transmitting intermediate elements, and a number of intermediate elements corresponds to a number of spring elements.
Claims
1. A torsional vibration damper for a clutch disk within a drive train of a motor vehicle, comprising: an input part arranged around an axis of rotation; a spring device comprising at least three spring elements; an output part which can be rotated relative to the input part about the axis of rotation to a limited extent against the spring device; torque-transmitting intermediate elements arranged between the input part and the output part for forcible radial translation by means of cam mechanisms when the input part rotates relative to the output part, wherein: the spring device is arranged between the torque-transmitting intermediate elements; and a number of intermediate elements corresponds is equivalent to a number of spring elements.
2. The torsional vibration damper of claim 1, wherein: each of the at least three spring elements has an effective direction; and the effective direction of each of the at least three spring elements spans a non-zero first angle with the effective direction of any other of the at least three spring elements.
3. The torsional vibration damper of claim 1, wherein: each intermediate element comprises a relative movement direction in which it can be moved during operation; and each of the at least three spring elements has an effective direction that spans a non-zero second angle with each relative movement direction.
4. The torsional vibration damper of claim 1, wherein: each of the at least three spring elements comprises an effective direction; and each effective direction is tangential to a circle having a circle radius with a center point lying on the axis of rotation.
5. The torsional vibration damper of claim 1, wherein all intermediate elements are of identical design.
6. The torsional vibration damper of claim 1, wherein the spring device comprises non-identical spring elements.
7. A clutch disk comprising the torsional vibration damper of claim 1.
8. The clutch disk of claim 7, further comprising a lining ring fastened on a radial outside of the input part.
9. A clutch comprising the clutch disk of claim 7.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) Both the disclosure and the technical environment will be explained in more detail below with reference to the figures. It should be pointed out that the disclosure is not intended to be limited by the exemplary embodiments shown. For example, unless explicitly stated otherwise, it is also possible to extract partial aspects of the matter explained in the figures and to combine same with other components and findings from the present description and/or figures. For example, it should be pointed out that the figures and, in particular, the proportions shown, are only schematic. The same reference numerals designate the same objects, so that explanations from other figures can be used as a supplement. In the figures:
(2) FIGS. 1 and 2 show a known torsional vibration damper;
(3) FIG. 3 shows a section of a first example of a torsional vibration damper;
(4) FIGS. 4 and 5 show further views of the first example of a torsional vibration damper;
(5) FIGS. 6 and 7 show the intermediate elements and spring elements of the first example in the undeflected and deflected state;
(6) FIGS. 8 and 9 show a detailed view of the forces applied to the intermediate element in the first example of a torsional vibration damper in the undeflected and deflected state;
(7) FIGS. 10 and 11 show a second example of a torsional vibration damper in the undeflected and deflected state in section;
(8) FIGS. 12 and 13 show a third example of a torsional vibration damper in the undeflected and deflected state in section;
(9) FIG. 14 shows details of the first example of a torsional vibration damper; and
(10) FIG. 15 shows very schematically a friction clutch having torsional vibration dampers.
DETAILED DESCRIPTION
(11) In the description of the figures, the same parts are provided with the same reference symbols. The torsional vibration damper 1 shown as known in FIGS. 1 and 2 comprises an input part 2, intermediate elements 3, cam mechanisms 4, 5, having ramp devices 6, 7, and a spring device 8 having spring elements 9 arranged between the intermediate elements 3 ,and an output part 10. The input part 2 of the torsional vibration damper 1 of FIG. 1 has ramps 11, such as cam tracks of the ramp devices 6, in the two cam mechanisms 4, for example, which are opposite one another with respect to the axis of rotation d of a shaft 17. Mutually opposite intermediate elements 3, each having two ramps 12 complementary to the input part 2, such as cam tracks of the ramp devices 6, and the rolling elements 13 complete the cam mechanism 4 between the input part 2 and the intermediate elements 3. When the input part 2 is rotated around the axis of rotation d, the rolling elements 13 are guided on the ramps 11, 12 such that the radial movement of the intermediate elements 3 results in a parallel spring compression of the spring elements 9, which are arranged between the intermediate elements 3. The ramps 11 of the input part 2 and the ramps 12 of the intermediate elements 3, together with the associated rolling elements 13, form the cam mechanism 4.
(12) The intermediate elements 3 each comprise a further ramp 14 radially on the inside, which are operatively connected to ramps 15 arranged in the output part 10. When the output part 10 is rotated around the axis of rotation d in the opposite direction to the rotation of the input part 2, the intermediate elements 3 are also guided via rolling elements 16 which roll freely between the appropriately designed ramps 14, 15 such that the movement thereof again signifies a parallel spring compression of the spring elements 9. The ramps 14 of the intermediate elements 3 and the ramps 15 of the output part 10 together with the associated rolling elements 16 form the cam mechanism 5.
(13) As a result of the coupling of the two cam mechanisms 4, 5 via the intermediate elements 3, the total angle of rotation between the input part 2 and the output part 10 results from the sum of the angles of rotation which are set in the respective cam mechanism 4, 5 having a certain spring compression of the spring elements 9. The torque at the input part 2 for the rotational movement is supported as a pure torsional moment at the output part 10. The unit consisting of intermediate elements 3 and spring elements 9 is not subject to an external torque effect, but determines the amount of the transmitted torque via the amount of force from the parallel spring compression of the spring elements 9.
(14) The ramps 11, 12, 14, 15 of the cam mechanisms 4, 5 of the torsional vibration damper 1 are linear in design, for example, to transmit the movements during rotation in the marked direction and to indicate the ability to transmit torque in contact via the rolling elements 13, 16 in this direction. In the case of constructions carried out, on the other hand, the design of the ramps 11, 12, 14, 15 is a free form as a result of the desired translations for the torsion characteristic curve while fulfilling the rolling conditions for the rolling elements 13, 16.
(15) FIG. 3 shows an example of a clutch disk 17 having a torsional vibration damper 1. The input part 2, output part 10, and intermediate elements 3 are operatively connected to one another analogously to those in the example in FIGS. 1 and 2. Reference is made to the statements made there, so that here and in the following, essentially the differences with respect to the torsional vibration damper assumed to be known are described. The same elements are provided with identical reference symbols in all figures.
(16) The torsional vibration damper 1 in this example has in comparison to the example from FIGS. 1 and 2, three intermediate elements 3, three input parts 2, three output parts 10, and a spring device 8 having three spring elements 9. Individual springs or spring assemblies made of several springs can be formed as spring elements 9. For the sake of clarity, only one input part 2, one output part 10 and two spring devices 8 are shown in FIG. 3. Each input part 2 is connected radially on the outside to a lining ring 18 which is connected directly or indirectly to friction linings (not shown here) so that a friction clutch can be assembled together with a pressure plate. The output part 10 can be rotated to a limited extent around the axis of rotation d relative to the corresponding input part 2 against the action of the spring device 8 having the two spring elements 9 arranged on the corresponding intermediate piece 3. The output parts 10 are connected via a hub 19 to a shaft (not shown here), for example, a transmission input shaft. In operation, a torque can be transmitted from the respective input part 2, and thus from the lining ring 18, via the intermediate elements 3 to the output part 10 and the hub 19. In this example, all intermediate elements 3 are identical. In this example, all spring elements 9 are also identical.
(17) FIGS. 4 and 5 show two views of a clutch disk 17 having three input parts 2 (only one input part 2 is shown in FIG. 5 for the sake of clarity), three output parts 10 and three intermediate parts 3, which are connected to one another by three spring elements 9 of a spring device 8. The torsional vibration damper 1 is shown in the undeflected state. The intermediate elements 3 are identical, as are the spring elements 9.
(18) FIG. 6 shows part of a torsional vibration damper 1 according to FIGS. 3 to 5 in the undeflected state, and FIG. 7 shows the same part of the torsional vibration damper 1 in the deflected state. Due to the design of the intermediate elements 3 and the ramps (not shown here) of the intermediate parts 3 and the input parts 2 and output parts 10 (not shown here), a movement of the intermediate parts 3 is only possible in the radial direction, where corresponding arrows in this relative movement direction 20 are shown in FIG. 7. FIGS. 6 and 7 also show the outer circumference 21 of the undeflected intermediate elements 3. It can be seen that the outer circumference is reduced in the deflected state by the radially inward movement of the intermediate elements 3 and the spring elements 8 are compressed. The spring elements 8 have a first length l1 in the undeflected state and a second length l2 in the deflected state, which is smaller than the first length l.sub.1. The spring elements (energy storage) 9 are thus compressed in the deflection by the intermediate elements 3.
(19) Each spring element 9 has an effective direction 22. The effective direction 22 is displaced in parallel by the deflection of the intermediate elements 3 (cf. FIGS. 6 and 7). In addition, the effective directions 22 are not aligned parallel to one another.
(20) FIGS. 8 and 9 schematically show the effective directions 22 and applied forces in the example according to FIGS. 3 to 7. FIG. 8 shows the undeflected case analogous to FIG. 6. The spring elements 9 exert a spring force F.sub.F in the effective direction 22 on the intermediate element 3. The spring forces F.sub.F are in vectorial equilibrium with the rocker force F.sub.W applied to the intermediate element 3. If the rocker force F.sub.W increases, the intermediate element 3 is pressed radially inward in the direction of the rocker force F.sub.W. As a result, the spring elements 9 are compressed and the spring force F.sub.F increases until the spring forces F.sub.F are again in vector equilibrium with the rocker force F.sub.W. The deflection of the spring elements 9 is reduced from the first length l.sub.1 (see FIG. 8) to the second length l.sub.2 (see FIG. 9).
(21) FIGS. 8 and 9 also show a first angle 23 between the effective directions 22 of two adjacent spring elements 9, this being non-zero for all effective directions 22 of all spring elements 9. Furthermore, by way of example, FIG. 9 shows a second angle 24 between the effective direction 22 of a spring element 9 and a relative movement direction 20 of an intermediate element 3.
(22) FIGS. 10 to 13 show two further examples of a torsional vibration damper 1 in which are formed four intermediate elements 3 having a spring device 8 with four spring elements 9. Each spring element 9 is connected to two intermediate elements 3 adjacent in the circumferential direction and connects them to one another.
(23) FIGS. 10 and 11 show an example of a torsional vibration damper 1 in the undeflected state which is rotationally symmetric. Here, four identical spring elements 9 are formed between the intermediate elements 3. All spring elements 9 here have a first length l.sub.1 in the undeflected state. FIG. 11 shows an example of the torsional vibration damper 1 in the deflected state. Here, the spring elements 9 are compressed to a second length l.sub.2 by the movement of the intermediate elements 3 in the direction of the relative movement direction 20.
(24) FIGS. 12 and 13 show a further example of a non-rotationally symmetric torsional vibration damper 1 having four non-identical intermediate elements 3 and spring elements 9. Here are formed two opposite first spring elements 29 and two opposite second spring elements 30, which differ in the length thereof in the undeflected state and possibly in the spring constant thereof. The intermediate elements 3 lying therebetween in the circumferential direction are correspondingly adapted so that all intermediate elements 3 have a common outer circumference 21. The first 29 and second spring elements 30 and the corresponding ramps of the intermediate elements 3 are designed such that also in this example, the intermediate elements 3 are displaced radially inward in the deflected state.
(25) By forming first 29 and second spring elements 30, a torsional vibration damper 1 can be achieved, which enables making the use of the interior between the intermediate elements 3 more flexible. A comparison of FIGS. 13 and 11 shows that the asymmetric configuration of the torsional vibration damper 1 according to FIGS. 12 and 13 also results in a change in the relative movement directions 20 of the intermediate elements 3.
(26) FIG. 14 shows a further example of a torsional vibration damper 1 having three intermediate elements 3 and a spring device 8 having three spring elements 9. Each spring element 9 has an effective direction 22, which is defined by the orientation and configuration of the spring element 9. The spring elements 9 are arranged so that they are tangential to a circle 25 which has a circle radius 26 and the center point 27 of which lies on the axis of rotation d.
(27) FIG. 15 very schematically shows a clutch 28 which comprises a clutch disk 17 which comprises at least one torsion damper 1 as described here.
REFERENCE NUMERALS
(28) 1 Torsional vibration damper
(29) 2 Input part
(30) 3 Intermediate element
(31) 4 Cam mechanism
(32) 5 Cam mechanism
(33) 6 Ramp device
(34) 7 Ramp device
(35) 8 Spring device
(36) 9 Spring element
(37) 10 Output part
(38) 11 Ramp
(39) 12 Ramp
(40) 13 Rolling element
(41) 14 Ramp
(42) 15 Ramp
(43) 16 Rolling element
(44) 17 Clutch disk
(45) 18 Lining ring
(46) 19 Hub
(47) 20 Relative direction of movement
(48) 21 Outer circumference
(49) 22 Effective direction
(50) 23 First angle
(51) 24 Second angle
(52) 25 Circle
(53) 26 Circle radius
(54) 27 Center point
(55) 28 Clutch
(56) 29 First spring element
(57) 30 Second spring element
(58) d Axis of rotation
(59) F.sub.F Spring force
(60) .sub.W Rocker force
(61) l.sub.1 First length
(62) l.sub.2 Second length