Torsional vibration damper with a rotational axis for a powertrain

Abstract

A torsional vibration damper includes an input side for receiving a torque, an output side for dispensing the torque, an intermediate element arranged for torque transmission between the input side and the output side, an energy storage element supporting the intermediate element such that it can vibrate relative to the input side and the output side, and a roll body. The intermediate element has a transmission path for the roll body. The input side or the output side forms a path side with a counter path that is complementary to the transmission path, and the other of the input side or the output side forms a force side. The roll body is guided in a rotatable manner between the transmission path and the counter path, and the energy storage element connects the force side to the intermediate element for torque transmission.

Claims

1.-7. (canceled)

8. A torsional vibration damper having a rotational axis for a powertrain of a motor vehicle, comprising: an input side for receiving a torque; an output side for dispensing the torque; an intermediate element arranged for torque transmission between the input side and the output side; a first energy storage element supporting the intermediate element such that the intermediate element can vibrate relative to the input side and the output side; and a first roll body, wherein: the intermediate element comprises a transmission path for the first roll body; a one of the input side or the output side forms a path side with a counter path that is complementary to the transmission path; the other one of the input side or the output side forms a force side; the first roll body is guided in a rotatable manner between the transmission path and the counter path; and the first energy storage element connects the force side to the intermediate element for torque transmission.

9. The torsional vibration damper of claim 8, wherein the intermediate element is mounted solely by the first energy storage element and the first roll body.

10. The torsional vibration damper of claim 8, further comprising a second energy storage element, wherein: the intermediate element is connected to the force side for torque transmission by the first energy storage element and the second energy storage element.

11. The torsional vibration damper of claim 10, wherein: the first energy storage element exerts a first force and a first direction of force on the intermediate element; the second energy storage element exerts a second force and a second direction of force on the intermediate element; and the first force and the second force differ from each other in a rest position; or the first direction of force and the second direction of force differ from each other in the rest position.

12. The torsional vibration damper of claim 8, further comprising a second roll body, wherein the intermediate element is supported on the path side by the first roll body and the second roll body.

13. The torsional vibration damper of claim 8, wherein the intermediate element is supported on the path side by the first roll body.

14. The torsional vibration damper of claim 8, wherein: the transmission path and the counter path comprise: a traction torque pairing with a first transmission curve; and a thrust torque pairing with a second transmission curve; the traction torque pairing is arranged for torque transmission from the input side to the output side; the thrust torque pairing is arranged for torque transmission from the output side to the input side; and a first transmission pathway of the first transmission curve differs from a second transmission pathway of the second transmission curve, at least in sections.

15. The torsional vibration damper of claim 8, wherein the first energy storage element is a helical compression spring with a straight spring axis.

16. The torsional vibration damper of claim 15, wherein the first energy storage element is displaceably mounted on the intermediate element or on the force side transversely to the straight spring axis.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0051] The above disclosure is explained in detail below based on the relevant technical background with reference to the associated drawings, which show example embodiments. The disclosure is in no way restricted by the purely schematic drawings, and it should be noted that the drawings are not dimensionally accurate and are not suitable for defining proportions. In the figures,

[0052] FIG. 1 shows a principle sketch of a torsional vibration damper in a first embodiment;

[0053] FIG. 2 shows a principle sketch of a torsional vibration damper in a second embodiment;

[0054] FIG. 3 shows a diagram of the forces applied to an intermediate element;

[0055] FIG. 4 shows a force triangle of the applied forces according to FIG. 3;

[0056] FIG. 5 shows a principle sketch of a torsional vibration damper in a third embodiment;

[0057] FIG. 6 shows a principle sketch of a torsional vibration damper in a fourth embodiment;

[0058] FIG. 7 shows a moment-angle of rotation diagram with a first transmission pathway;

[0059] FIG. 8 shows a moment-angle of rotation diagram with a second transmission pathway;

[0060] FIG. 9 shows a moment-angle of rotation diagram with a third transmission pathway; and

[0061] FIG. 10 shows a moment-angle of rotation diagram with a fourth and fifth transmission pathway.

DETAILED DESCRIPTION

[0062] By way of example, FIG. 1, FIG. 2, FIG. 5, and FIG. 6 each show in a principle sketch different embodiments of a torsional vibration damper 1, which for the sake of clarity are depicted largely in the same manner and insofar as the descriptions of the same components are cross-referenced for the respective figures. Here, an annular disk forms an input side 4, which forms the path side 13 in FIGS. 1 and 5 and forms the force side 14 in FIGS. 2 and 6. In the center of the common rotational axis 2, a further disk element is formed, for example, as the output side 5, which forms the force side 14 in FIG. 1 and FIG. 5 and forms the path side 13 in FIG. 2 and FIG. 6. Alternatively, the annular disk is the output side 5 and the disk element is the input side 4. The variant mentioned above is described below, wherein the terms are interchangeable.

[0063] As indicated by the arrows, a traction torque 28 can be transmitted from the input side 4 to the output side 5 and a thrust torque 29 can be transmitted from the output side 5 to the input side 4. In one embodiment, the torque direction is set up in reverse.

[0064] Two intermediate elements 6, 7 are provided between the input side 4 and the output side 5. The respective intermediate element 6, 7 of the paired first energy storage element 16 and second energy storage element 17 are connected to the force side 14 in a force-transmitting manner, and thus so as to transmit a torque, and on the path side by means of a transmission path 12. A first or second roll body 8, 9 rolling on the transmission path to the complementary counter path 15 on the path side 13 is supported in a force-transmitting manner and thus so as to transmit a torque. The roll bodies 8, 9 are here pretensioned by means of the energy storage elements 16, 17, against the transmission path 12, and against the counter path 15, and are thus guided in a rotatable manner.

[0065] The energy storage elements 16, 17 hold the intermediate elements 6, 7, acting antagonistically to each other in a rest position in the position shown. To the side of the rest position in which the second roll body 9 is shown, a traction torque pairing 18 from the respective complementary ramp portion of the transmission path 12 and the counter path 15 is formed, and a thrust torque pairing 20 on the other side out of the complementary ramp portions of the transmission path 12 and the counter path 15, is also formed. The mechanism of action thereof is explained in detail below. In the embodiments shown, the intermediate elements 6, 7 are supported solely via the energy storage elements 16, 17 and the respective roll bodies 8, 9.

[0066] In FIG. 2, in comparison to FIG. 1, a reverse embodiment is shown with regard to the path side 13 and force side 14, so that the input side 4 here forms the force side 14 and the output side 5 forms the path side 13.

[0067] FIG. 3 shows a diagram of the moment equilibrium and FIG. 4 shows a force triangle via the first intermediate element 6, the second intermediate element 7 with a first roll body 8 and the second roll body 9 according to the embodiment in FIG. 1. Here, the intermediate element 6, 7 is led out of the rest position thereof and is deflected at an angle of deflection to the rest position with the center line 33 inclined to the line of rest 32. The line of rest 32, which in the rest position is congruent with the center line 33, always runs through the rotational axis 2 like the center line 33, but only in the rest position through the moment balance point 3 of the intermediate element 6, 7.

[0068] The center line 33, which is not to be understood as the geometric or mass-related center, but rather the force-related center of the intermediate element 6, 7, always runs through the moment balance point 3 and the rotational axis 2. At this moment balance point 3 of the intermediate element 6, 7, there must be a moment equilibrium if it is required that no additional guidance for the intermediate element 6, 7 is necessary. The line of rest 32 must always be aligned perpendicular to the adjacent (theoretically infinitesimal) section of the transmission path 12. The line of rest 32 runs through the moment balance point 3 and the rolling axis of the roll bodies 8, 9.

[0069] To ensure that this rule is always adhered to, a parallel of the first action line 30 of the first force 22, starting from the first energy storage element 16, with a second parallel, which is at an equal distance or is spaced apart in proportion to the force, of the second action line 31 of the second force 23, intersects the center line 33 and the line of rest 32 in the moment balance point 3, starting from the second energy storage element 17, so that no (active) lever arm arises. Furthermore, it is required that the first force 22, the second force 23, and the resulting force 26 form a self-canceling force triangle, as shown in FIG. 4.

[0070] For this purpose, the first direction of force 24, the second direction of force 25 and the resulting direction of force 27 must be present as shown. It follows from the position shown that both the first energy storage element 16 (see FIG. 1) and the second energy storage element 17 (see FIG. 1) are more strongly tensioned, as a result of Which an increased pretensioning force acts on the intermediate element 6, 7. In this embodiment, the stronger tensioning follows from a movement of the intermediate element 6, 7 radially inward, so that the energy storage elements 16, 17 are also moved radially inward and are compressed between the adjacent intermediate elements 6, 7 like a screw clamp. The intermediate elements 6, 7 are thus moved in such a way that the resulting distance along the spring axes 37, 38 of the energy storage elements 16, 17 between the intermediate elements 6, 7 and the force side 14 is shortened compared to the rest position, provided that an increased rigidity at a higher torque is desired (compare FIGS. 5 through 8).

[0071] For the correct alignment of the pressure lines 34, i.e., the action lines of the resulting force 26, it is necessary that the pressure line 34, which intersects the rolling axis of the roll body 8, 9 and the moment balance point 3, are always perpendicular to the transmission path 12, here the second transmission curve 21, which is assigned to the thrust torque 29. The respective amount of the resulting force 26 and the resulting direction of force 27 then result intrinsically from the applied first force 22 and second force 23.

[0072] FIGS. 5 and 6 show variants of the embodiments in FIG. 1 and in FIG. 2. Here a constrained guidance is present on the intermediate elements 6, 7, in which in addition to the first roll body 8 and the second roll body 9, also a further, namely a third or a fourth, roll body 10, 11 is provided. In this embodiment, one embodiment deviates from the requirement of a moment equilibrium and an equilibrium of forces over the respective intermediate element 6, 7. All that is required is that a sufficient force (vector) component is generated by the (first) energy storage element 16 (and here also the second energy storage element 17) to hold the roll bodies 8, 9, 10, 11 between the respective transmission path 12 and the complementary counter path 15 or to press the respective intermediate element 6, 7 against the two roll bodies 8, 9, 10, 11. In principle, more roll bodies 8, 9, 10, 11 can also be used. Otherwise, with regard to FIG. 5, reference is made to the description of FIG. 1 or, with regard to FIG. 6, to the description of FIG. 2.

[0073] Torque-rotation angle diagrams are shown in FIGS. 7 through 10, in which the torque axis 35 forms the ordinate and the rotation angle axis 36 forms the abscissa. In this example, to the right of the ordinate is a traction torque pathway 28 with a positive dissipated moment and angle of rotation, and to the left of the ordinate is a thrust torque pathway 29 with a negative dissipated moment and angle of rotation.

[0074] FIG. 7 shows a first transmission curve 19, then associated with the traction torque pairing 18, and a second transmission curve 21, then associated with the thrust torque pairing 20, in a two-part progressive form, so that there is a flat curve slope at low torque amounts, and there is a steep curve slope at high torque amounts.

[0075] In FIG. 8 is shown a corresponding two-part degressive variant in which there is a steep curve slope at low torque amounts and a flattened curve slope at high torque amounts.

[0076] FIG. 9 shows a variant in which a progressive and degressive pathway alternate and FIG. 10 shows a rigid system having a steep curve pathway, shown with a solid line, in comparison with a system having a flat curve course shown with dashed line.

[0077] For the embodiment in FIG. 1 and FIG. 2 without additional guidance of the intermediate element 6, 7, such a transmission curve 19, 21 is to be observed in accordance with the moment equilibrium and force equilibrium as explained in FIG. 3 and FIG. 4. The transmission curve 19, 21 shown is therefore designed to be superimposed with the requirement for the transmission path 12 according to the description of FIG. 1 (and FIG. 2). Furthermore, in one embodiment, the (first) force 22 or the rigidity of the first energy storage element 16 is different from the second energy storage element 17 in the rest position and is not designed to be symmetrical as indicated in FIGS. 1 and 2. This must also be taken into account for the superimposition to achieve the desired transmission curve 19, 21.

[0078] The torsional vibration damper proposed here enables an inexpensive and efficient influence on the natural frequency to be achieved using few components.

REFERENCE NUMERALS

[0079] 1 Torsional vibration damper

[0080] 2 Rotational axis

[0081] 3 Moment balance point

[0082] 4 Input side

[0083] 5 Output side

[0084] 6 First intermediate element

[0085] 7 Second intermediate element

[0086] 8 First roll body

[0087] 9 Second roll body

[0088] 10 Third roll body

[0089] 11 Fourth roll body

[0090] 12 Transmission path

[0091] 13 Path side

[0092] 14 Force side

[0093] 15 Counter path

[0094] 16 First energy storage element

[0095] 17 Second energy storage element

[0096] 18 Traction torque pairing

[0097] 19 First transmission curve

[0098] 20 Thrust torque pairing

[0099] 21 Second transmission curve

[0100] 22 First force

[0101] Second force

[0102] 24 First direction of force

[0103] 25 Second direction of force

[0104] 26 Resulting force

[0105] 27 Resulting direction of force

[0106] 28 Traction torque

[0107] 29 Thrust torque

[0108] 30 First action line

[0109] 31 Second action line

[0110] 32 Rest line

[0111] 33 Center line

[0112] 34 Pressure line

[0113] 35 Torque axis

[0114] 36 Rotation angle axis

[0115] 37 First spring axis

[0116] 38 Second spring axis