DEVICE FOR DAMPING TORSIONAL OSCILLATIONS

Abstract

A device for damping torsional oscillations including at least one support being displaced rotationally about an axis, a plurality of pendular bodies, each pendular body being mobile in relation to the support, and a friction-based connection between two circumferentially adjacent pendular bodies.

Claims

1. A device for damping torsional oscillations, comprising: at least one support capable of being displaced rotationally about an axis, a plurality of pendular bodies, each pendular body being mobile in relation to the support (2), and a friction-based connection between two circumferentially adjacent pendular bodies, the friction-based connection implementing a friction between axially facing friction surfaces.

2. The device as claimed in claim 1, comprising a plurality of friction-based connections, such that, for each pendular body: there is a friction-based connection with the pendular body that is circumferentially adjacent in the counter-clockwise direction, and there is a friction-based connection with the pendular body that is circumferentially adjacent in the clockwise direction.

3. The device as claimed in claim 2, the friction-based connection being produced using at least one tab integral to one of the two circumferentially adjacent pendular bodies and rubbing against the other of these two pendular bodies.

4. The device as claimed in claim 3, the tab having a fixing part on one of the two pendular bodies and a free end rubbing against the other of the two pendular bodies, the part of this tab positioned between the fixing part and the free end of the tab being in particular undulated.

5. The device as claimed in claim 4, the tab being such that its free end is permanently axially facing the pendular body to which it is not integral, such that this free end can rub against this pendular body.

6. The device as claimed in claim 1, the friction-based connection being produced via a piece extending all around the axis of rotation of the support and mobile in relation to the support, this piece rubbing against each pendular body.

7. The device as claimed in claim 1, comprising a plurality of rolling members, each rolling member cooperating with a first rolling track integral to the support and with a second rolling track integral to a pendular body, the displacement of each pendular body in relation to the support being guided by at least two of these rolling members.

8. The device as claimed in claim 7, the support comprising a plurality of windows in each of which two rolling members are received, one of these rolling members cooperating with a second rolling track integral to one of the two circumferentially adjacent pendular bodies and the other of these rolling members cooperating with a second rolling track integral to another of these two circumferentially adjacent pendular bodies, each friction-based connection being positioned in a window between the two rolling members present in this window.

9. The device as claimed in claim 1, the support being singular and each pendular body comprising: a first and a second pendular weight axially spaced apart from one another, the first pendular weight being positioned axially on a first side of the support and the second pendular weight being positioned axially on a second side of the support, and at least one link member of the first and of the second pendular weights, pairing said weights.

10. The device as claimed in claim 9, each pendular body comprising two link members pairing the first and the second pendular weights, each link member defining a second rolling track cooperating respectively with one of the two rolling members guiding the displacement of this pendular body in relation to the support.

11. The device as claimed in claim 9, each rolling member cooperating with two second rolling tracks integral to the pendular body, one of these second rolling tracks being defined by the first pendular weight and the other of these second rolling tracks being defined by the second pendular weight.

12. The device as claimed in claim 10, wherein the friction-based connection is produced using at least one tab integral to one of the two circumferentially adjacent pendular bodies and rubbing against the other of these two pendular bodies, each friction-based connection comprising: a first tab positioned on the first side of the support, the first tab being integral to a first pendular weight of one of the two pendular bodies and rubbing against the first pendular weight of the other of the two pendular bodies, and a second tab positioned on the second side of the support, the second tab being integral to a second pendular weight of one of the pendular bodies and rubbing against the second pendular weight of the other of the two pendular bodies.

13. The device as claimed in claim 1, comprising two distinct axially offset and integral supports, each pendular body comprising at least one pendular weight positioned axially between the two supports.

14. The device as claimed in claim 1, being configured such that the displacement of the pendular bodies makes it possible to filter the order of excitation of a two-cylinder vehicle heat engine.

15. A component for a transmission of a motor vehicle system, comprising a device for damping torsional oscillations as claimed in claim 1, the component being in particular a dual mass flywheel, a hydrodynamic torque converter, a friction clutch disk, a crankshaft-integral flywheel, a dry or wet doable clutch, a wet single clutch, or a component of a hybrid power train.

Description

[0116] The invention will be able to be better understood on reading the following description of nonlimiting exemplary implementations thereof and on studying the attached drawing in which:

[0117] FIG. 1 represents a device for damping torsional oscillations according to a first variant of a first exemplary implementation of the invention,

[0118] FIG. 2 represents a detail of the device of FIG. 1,

[0119] FIG. 3 represents an alternative to what is represented in FIG. 2,

[0120] FIGS. 4 and 5 represent another alternative to what is represented in FIG. 2, FIG. 5 being a view in cross section along V-V of FIG. 4,

[0121] FIG. 6 represents, like FIG. 4, a device for damping torsional oscillations according to a second variant of the first exemplary implementation of the invention,

[0122] FIGS. 7 to 9 represent a device for damping torsional oscillations according to a first variant of a second exemplary implementation of the invention, FIG. 8 being a view in cross section along VIII-VIII of FIG. 7, and FIG. 9 differing from FIG. 7 by the fact that one of the supports is not represented therein and by the fact that the pendular bodies are not fully represented therein, and

[0123] FIGS. 10 and 11 represent a device for damping torsional oscillations according to a second variant of a second exemplary implementation of the invention, FIG. 11 differing from FIG. 10 by the fact that one of the supports is not represented therein and by the fact that the pendular bodies are not fully represented therein.

[0124] FIG. 1 shows a device 1 for damping torsional oscillations according to a first variant of a first exemplary implementation of the invention.

[0125] The damping device 1 is of pendular oscillator type. The device 1 is in particular capable of equipping a motor vehicle transmission system, being for example incorporated in a component (not represented) of such a transmission system, this component being, for example, a dual mass flywheel, a hydrodynamic torque converter or a clutch disk.

[0126] This component can form part of a power train of a motor vehicle, this power train comprising a heat engine in particular with two, three or four cylinders.

[0127] In FIG. 1, the device 1 is at rest, that is to say that it does not filter the torsional oscillations transmitted by the propulsion chain because of the rotational irregularities of the heat engine.

[0128] As is known, such a component can comprise a torsion damper having at least one input element, at least one output element, and circumferentially-acting elastic return members which are interposed between said input and output elements. Within the meaning of the present application, the terms input and output are defined in relation to the direction of transmission of the torque from the heat engine of the vehicle to the wheels thereof.

[0129] In the example considered, the device 1 comprises:

[0130] a support 2 capable of being rotationally displaced about an axis X, and

[0131] a plurality of pendular bodies 3 that are mobile in relation to the support 2.

[0132] According to the first exemplary implementation of the invention, which will be described with reference to FIGS. 1 to 6, the support 2 is singular. It will be noted also in FIGS. 1 to 6 that three pendular bodies 3 are provided, being distributed uniformly over the perimeter of the axis X.

[0133] The support 2 of the damping device 1 can be composed of:

[0134] an input element of the torsion damper,

[0135] an output element or an intermediate phasing element positioned between two series of springs of the damper,

[0136] an element rotationally linked to one of the abovementioned elements and distinct therefrom, being then for example a support specific to the device 1.

[0137] The support 2 is in particular a guiding washer or a phasing washer. The support can also be something else, for example a flange of the component.

[0138] In the example considered, the support 2 is overall in the form of a ring comprising two opposite sides 4 which here are planar faces.

[0139] As can notably be seen in FIGS. 1 to 5, each pendular body 3 comprises, in the example considered:

[0140] two pendular weights 5, each pendular weight 5 extending axially facing a side 4 of the support 2, and

[0141] two link members 6 securing the two pendular weights 5.

[0142] The link members 6, also called spacers, can be seen better in FIGS. 3 and 4, and in the examples considered, they are angularly offset. Each body 3 extends angularly between two circumferential ends, which correspond respectively to the circumferential ends 7 and 8 of the pendular weights 5 of this body.

[0143] In the, example of FIGS. 1 and 2 and in the example of FIGS. 4 and 5, each link member 6 is screwed onto one of the pendular weights 5 via screws 9 that can be seen in FIG. 1 so as to secure the latter to one another. In the alternative represented in FIG. 3, each end of a link member 6 is force-fitted into an opening formed in one of the pendular weights 5 of the pendular body 3, so as to secure these two pendular weights 5 to one another.

[0144] In yet another alternative, each end of a link member 6 is secured to one of the pendular weights 5 by welding.

[0145] In yet another alternative, each link member is riveted to one of the pendular weights 5.

[0146] The device 1 also comprises rolling members 11 that can be seen in FIGS. 3 and 4 for example, guiding the displacement of the pendular bodies 3 in relation to the support 2. The rolling members 11 here are rollers.

[0147] In the example described, the movement in relation to the support 2 of each pendular body 3 is guided by two rolling members 11. This movement is for example a combined movement.

[0148] Each rolling member 11 is received in a window 19 formed in the support 2. In the example of FIGS. 1 and 2 and in the example of FIGS. 4 and 5, one and the same window 19 formed in the support 2 receives the two rolling members 11 guiding the displacement of a pendular body 3 in relation to the support 2.

[0149] Each window 19 has a closed outline 16 and a part of this outline 16 defines a first rolling track 12 integral to the support 2, on which one of the rolling members 11 received in this window 19 will roll, while another part of this closed outline 16 defines another first rolling track 12 integral to the support 2, on which the other rolling member 11 received in the window 19 will roll.

[0150] In the example of FIG. 3, one and the same window formed in the support 2 receives a rolling member 11 guiding the displacement of a pendular body 3 in relation to the support and a rolling member 11 guiding the displacement of a circumferentially adjacent pendular body in relation to the support 2. Each window 19 has a closed outline 16, this closed outline having a part defining a first rolling track 12 integral to the support 2, on which one of the rolling members 11 received in this window 19 will roll, while another part of this closed outline 16 defines another first rolling track 12 integral to the support 2, on which the other rolling member 11 received in the window 19 will roll.

[0151] In the example of FIGS. 1 to 5, each window 19 also receives two link members 6 of the pendular body 3.

[0152] Each link member 6 defines, in the example of FIGS. 1 to 5, a second rolling track 13 which is integral to the pendular body 3 to which this link member 6 belongs and on which one of the rolling members 11 rolls to guide the displacement of this pendular body 3 in relation to the support 2.

[0153] Each link member 6 has, in the, example of FIGS. 1 and 2 and in the example of FIGS. 4 and 5, on its radially inner edge, a notch 17 in which an abutment damping member 18 is received and, on its lateral edge 20 not facing the other link member 6 received in this window 19, a notch 21 in which another abutment damping member 22 is received. The abutment damping members 18 and 22 are for example produced in elastomer or in rubber. These abutment damping members 18 and 22 damp the shocks between the pendular body 3 and the support in case of radial drop when the engine of the vehicle stops and/or on completion of a travel of this pendular body 3 to filter a torsional oscillation.

[0154] According to the invention, two circumferentially adjacent pendular bodies 3 are linked by a friction-based connection 30. More specifically, in the examples described, the device 1 comprises a plurality of friction-based connections 30, such that, for each pendular body 3:

[0155] there is a friction-based connection 30 with the circumferentially adjacent pendular body 3 in the counter-clockwise direction, and

[0156] there is a friction-based connection 30 with the circumferentially adjacent pendular body 3 in the clockwise direction.

[0157] In FIGS. 1 and 2, which correspond to a first variant of a first exemplary implementation of the invention, this connection is of a first type.

[0158] In the example of FIGS. 1 and 2, each friction-based connection 30 implements two tabs 32, As can be seen more specifically in FIG. 2, each tab 32 can have a fixing part 33 on one of the pendular bodies 3 and a free end 34 rubbing against the other of the two pendular bodies 3. The fixing of a tab 32 on one of the pendular bodies 3 is performed in the example represented via screws 36, In the example of FIGS. 1 and 2, each free end 34 is bent back and the part 38 of a tab positioned between the fixing part 33 and the free end 34 is undulated. As can be seen in particular in FIG. 1, when the device 1 is at rest, each tab 32 extends substantially circumferentially between its fixing part 33 and its free end 34. Still in the example considered, each tab 32 is such that its free end 34 is permanently axially facing the pendular body 3 against which it has to rub.

[0159] In the example of FIGS. 1 and 2, a first tab 32 is positioned on the first side of the support and it is integral to the first pendular weight 5 of one of the pendular bodies 3 and rubs against the first pendular weight 5 of the other pendular body 3 while a second tab 32 is positioned on the second side 4 of the support 2 and this second tab 32 is integral to the second pendular weight 5 of the pendular body against which the first tab 32 rubs, and this second tab 32 rubs against the second pendular weight 5 of the pendular body 3 to which the first tab 32 is integral. Within one and the same friction-based connection, the mounting of the tabs 32 can thus be reversed.

[0160] Within one and the same friction-based connection 30, the first and second tabs 32 can be identical and produced in plastic or in spring-type steel.

[0161] FIG. 3 represents a variant friction-based connection 30 of the first type. According to this variant, the friction-based connection 30 implements a single tab 32 and this tab extends into the window 19 formed in the support 2 and which receives rolling members 11 guiding the displacement of two circumferentially adjacent pendular bodies. The fixing part 33 is, here, force-fitted into an opening formed in each pendular weight 5 and the part 38 extends into the window 19 between the two pendular bodies 3. The free end 34 here has two arms 39 extending substantially parallel, these two arms 39 being both positioned in the axial space delimited by the two pendular weights 5 of the pendular body 3 against which the single tab 32 rubs. These two arms 39 are such that each of them comes to rub against one of the pendular weights 5.

[0162] There now follows a description with reference to FIGS. 4 and 5 of an example of a second type of friction-based connection 30. According to the second type, as described with reference to FIGS. 4 and 5, all the friction-based connections between the pendular bodies 3 of the device implement a piece 40 extending all around the axis of rotation X of the support 2 and mobile in relation to the support 2. This piece 40 comes to rub against each pendular body 3. The piece 40 defines tabs 41 which will be described later, each tab protruding radially inward.

[0163] As can be seen in particular in FIG. 5, in which the link members 6 and the rolling members 11 are not represented, the piece 40 can take the form of two flanges 44 rigidly connected to one another via rivets 45 at their radially outer portion.

[0164] As can be seen in FIG. 5, a first flange 44 is positioned on a first side 4 of the support 2 and extends axially beyond the first pendular weight 5 such that one or more of the first tabs 41 that it bears come to rub against this first pendular weight 5. Likewise, a second flange 44 is positioned on a second side 4 of the support 2 and it extends axially beyond the second pendular weight 5 such that one or more second tabs 41 that it bears come to rub against this second pendular weight 5.

[0165] There now follows a description with reference to FIG. 6 of a second variant of the first exemplary implementation of the invention. According to this second variant, each rolling member 11 cooperates with two second rolling tracks 13 that are distinct and integral to a pendular body 3.

[0166] One of the second rolling tracks 13 is defined by the first pendular weight 5 of the pendular body 3 and the other of these second rolling tracks 13 is defined by the second pendular weight 5 of this pendular body 3. Each pendular weight 5 has, in this example, two cavities 43, and each of these cavities 43 receives a part of a rolling member 11 which cooperates with the second rolling track 13 formed by a part of the outline of this cavity 40. The first rolling track 12 with which this rolling member 11 cooperates is, as previously, formed by a part of the outline 16 of the window 19.

[0167] In the example of FIG. 6, each link member 6 is a rivet which is also received in the window 19.

[0168] According to the second variant of the first exemplary implementation of the invention which is described with reference to FIG. 6, the friction-based connection 30 between two circumferentially adjacent pendular bodies is of the second type described above, implementing, like what is described with reference to FIGS. 4 and 5, a piece 40 having two flanges 44 respectively bearing first tabs 41 rubbing against the first pendular weights 5 and second tabs 41 rubbing against the second pendular weights 5. Each first tab 41 and each second tab 41 extends over a given angular segment.

[0169] FIGS. 1 to 6 relate to the first exemplary implementation of the invention, whereby the device 1 comprises a single support and each pendular body 3 comprises two paired pendular weights each extending on one side 4 of the support 2.

[0170] There now follows a description, with reference to FIGS. 7 to 11, of two variants of a device for damping torsional oscillations according to a second exemplary implementation of the invention.

[0171] According to this second exemplary implementation of the invention, the device comprises two distinct axially offset and integral supports 2. Each pendular body 3 can comprise, according to this second exemplary implementation of the invention, a single pendular weight 5 positioned axially between the two supports 2. In the description below, each pendular body 3 comprises two pendular weights 5 secured to one another and which, as can be seen in FIG. 8, have forms allowing a housing 39 to be formed between the radially outer parts of these two pendular weights 5. The two integral pendular weights 5 are positioned axially between the two supports 2. In FIG. 9, only one of the two pendular weights 5 of a pendular body 3 is represented.

[0172] In the example of FIGS. 7 to 9, two caps 50 are positioned axially around the assembly formed by the two supports 2 and the pendular bodies 3, such that there are, in axial succession:

[0173] one of the caps 50,

[0174] one of the supports 2,

[0175] the two pendular weights 5,

[0176] the other of the supports 2, and

[0177] the other of the caps 50.

[0178] According to a first variant of this second exemplary implementation of the invention, which is represented in FIGS. 7 to 9, each pendular body 3 has a protuberance 56 protruding axially into a window 19 of one of the supports 2. This protuberance 56, which may or may not be produced of a single piece with one of the two pendular weights 5 of the pendular body 3, here defines a second rolling track 13 integral to the pendular body.

[0179] In the example represented in FIGS. 7 to 9, two protuberances 56 are provided on each side of the two pendular weights 5. From one side to the other of the two pendular weights 5, these protuberances can extend axially in opposite directions and be axially superposed. Two axially superposed protuberances 56 can be linked together and to the two pendular weights 5 via rivets 57, as represented in FIGS. 7 and 9.

[0180] As can be worked out in FIG. 8, the two protuberances 56 formed on a first side of the two pendular weights 5 then protrude into two different windows 19 of one of the supports 2 while the two protuberances 56 formed on a second side of the two pendular weights 5, opposite the first side, then protrude into two different windows 19 of the other of the two supports 2 of the device 1.

[0181] In the example considered, the displacement of each pendular body 3 in relation to the support 2 is guided by four distinct rolling members 11:

[0182] a first rolling member 11 cooperating with a first rolling track 12 defined by a part of the outline of one of the windows 19 formed in the support 2 positioned on the first side of the two pendular weights 5 and with a second rolling track 13 defined by one of the protuberances 56 formed on this first side of the two pendular weights 5,

[0183] a second rolling member 11 cooperating with a first rolling track 12 defined by a part of the outline of another window 19 formed in the support 2 positioned on the first side of the two pendular weights 5 and with a second rolling track 13 defined by another of the protuberances 56 formed on this first side of the two pendular weights 5,

[0184] a third rolling member 11 cooperating with a first rolling track 12 defined by a part of the outline of one of the windows 19 formed in the support 2 positioned on the second side of the two pendular weights 5 and with a second rolling track 13 defined by one of the protuberances 56 formed on this second side of the two pendular weights 5, and

[0185] a fourth rolling member 11 cooperating with a first rolling track 12 defined by a part of the outline of another window 19 formed in the support 2 positioned on the second side of the two pendular weights 5 and with a second rolling track 13 defined by another of the protuberances 56 formed on this second side of the two pendular weights 5.

[0186] In the example of FIGS. 7 to 9, each pendular body 3 is linked to the two pendular bodies 3 between which it is circumferentially positioned by means of a connection of the second type, the latter involving a piece 40 which differs from those described with reference to FIGS. 4 to 6 by the fact that this piece 40 is an annular washer. The piece 40 here is without tabs and it extends all around the axis of rotation X of the support, so as to be able to rub against each pendular body 3 of the device 1. The washer is received in the housing 39 and defines a succession of portions. The washer 40 here is a crinkle washer, for example of Onduflex type, and it thus occupies different successive axial positions in the housing 39.

[0187] Two successive portions of this washer 40 received in the housing 39 can thus rub against two different axial edges of this housing 39, that is to say against two different pendular weights 5 of the pendular body 3.

[0188] FIGS. 10 and 11 represent a second variant of this second exemplary implementation of the invention.

[0189] According to this second variant, each pendular weight 5 has at least two through cavities 43, such that each rolling member 11 is received:

[0190] in a window 19 formed in one of the two supports 2,

[0191] in a cavity 43 formed in the pendular weight 5, and

[0192] in a window 19 formed in the other of the two supports 2.

[0193] According to this second variant as described with reference to FIGS. 10 and 11, the friction-based connection 30 between two circumferentially adjacent pendular bodies 3 is again of the second type and the piece 40 is a washer that comes to rub against each pendular body 3 of the device, like what was described with regard to the first variant of this second exemplary implementation of the invention.

[0194] The invention is not limited to the examples which have just been described.

[0195] It is for example possible to combine together features described with reference to different embodiments.

[0196] By way of examples, a friction-based connection 30 of the first type can be used in the examples described with reference to FIGS. 6 to 11.

[0197] The figures of the present application are views that are to scale, such that measurements can be obtained therefrom by the person skilled in the art.