FR3069604B1 - ASSUPLIED PENDULUM DAMPING DEVICE - Google Patents

Abstract

Pendulum damping device, in particular intended to be integrated in a transmission chain of a motor vehicle, in particular in a clutch, the device comprising: - a support (12); a plurality of clocks arranged around an axis X of rotation of the support; a pendulum (13) comprising an oscillating weight (14) and at least one rolling member (16), interposed between said oscillating weight and the support so as to roll on bearing tracks of support and oscillating mass during the oscillation of the oscillating mass.

Description

ASSUPLIED PENDULUM DAMPING DEVICE

TECHNICAL FIELD The invention relates to a pendulum damping device, particularly for a clutch of a motor vehicle, and to a torsion damping device incorporating such a pendular damping device.

State of the art

A pendulum damping device is conventionally used to filter the vibrations due to motor acyclisms of a motor vehicle.

Conventionally, it comprises an annular support intended to be rotated, and several oscillating oscillating oscillating masses mounted on the support about an axis parallel to the axis of rotation of the support. The displacement of an oscillating mass relative to the support is generally guided by two rolling members each cooperating with a raceway of the support and a rolling track of the oscillating mass.

An oscillating mass is conventionally constituted by a pair of flyweights, sandwiching the support and rigidly secured to each other, generally by means of a spacer which defines the rolling track of the oscillating mass.

The pendulum damping device is conventionally fixed rigidly, by means of derivets, to a phasing washer of a torsion damping device, in particular a clutch, a hydrodynamic torque converter or a double wet clutch. The use of rivets allows a fast, efficient and inexpensive assembly.

Under the effect of shocks, the rivets can however break. The breaking of the rivets renders useless the pendulum damping device.

There is therefore a need to increase the life of the pendulum dampers.

An object of the invention is to meet this need. SUMMARY OF THE INVENTION To this end, the invention proposes a pendulum damping device, especially intended to be integrated in a transmission chain of a motor vehicle, in particular in a clutch, the device comprising: a support; a plurality of pendulums arranged around an axis X of rotation of the support, each pendulum comprising an oscillating mass and at least one rolling member, interposed between said oscillating mass and the support so as to roll on tracks of support and oscillating mass during oscillation of the oscillating weight in relation to the support.

Remarkably, in a pendulum damping device according to the invention, the support comprises one, preferably a plurality of notches configured to confer torsional flexibility on the support about the X axis.

The flexibility is determined so that the cuts close elastically, at least partially, under the effect of shocks to the device in use. The presence of such cuts thus considerably increases the lifetime of the pendulum damping device. Without being limited by this theory, the inventors explain the results obtained by the ability of the support to partially absorb transmitted shocks rivets, thanks to its elasticity in torsion.

Preferably the flexibility, or angular stiffness, of the support is equal to:

with,

Ksp: the flexibility of the support,

Nmot: the order of the engine, for example Nmot = 2 for a four-cylinder engine

Nmax: maximum engine speed in revolutions per minute, for example 5000-7000 rpm

Jsp: Inertia of the support,

The flexibility of the support can be between 270 Nm / ° and 4300 Nm / °.

A pendulum damping device according to the invention may also comprise one or more of the following optional and preferred features:

the notch opens on a radially inner edge or on a radially inner edge of the support. In one embodiment, at least one, preferably each, is substantially radial; - The support comprises a fixing lug, preferably substantially radial and, preferably, oriented towards the X axis, for the fixing of the damping devicependulaire on a phasing washer of a torsion damping device, the notch preferably extending, at least in part, in the bracket or at least partly delimiting an edge of said bracket; said notch has a length greater than the largest radial dimension of the support in the regions of the support adjacent to the notch and which, when the device is observed along the X axis, are covered by an oscillating mass; said notch extends radially with respect to the X axis; the support comprises several said notches, each notch being disposed, when the pendulum damping device is observed along the X axis, between regions of support supporting adjacent oscillating masses; - The support comprises a group of several notches, identical or different, arranged, when the pendulum damping device is observed along the axis X, between regions of the support supporting adjacent oscillating masses; the support is substantially plane and extends transversely; - At least one, preferably each notch has a maximum width greater than 5 mm and / or less than 30 mm, for example between 10 mm and 20 mm. - At least one, preferably each notch has a minimum width greater than the axial thickness of the support, for example 4 mm, for example 10 mm. - At least one, preferably each notch has a length greater than 50 mm to and / or less than 300 mm. at least one, preferably each notch is cut into a sheet constituting the support; - The notches are equi-angularly distributed around the axis X. The invention also relates to a torsion damping device incorporating pendulum damping device according to the invention.

Preferably, the pendulum damping device is fixed by means of at least one, preferably a plurality of rivets on a phasing washer of the torsion damping device, each rivet preferably passing through a bracket of the supportrespective.

Preferably, the width of a notch, preferably of each notch, is determined so as to allow, without rupture of the rivets, contact of the two parts of the support separated by said notch. In other words, at least one, preferably each notch comprises unfond and first and second lateral edges connected to said bottom, said notch having a width such that the first and second lateral edges can be brought into contact with one another, without breaking of a said rivet, by torsion of the support around the axis X.

The torsion damping device according to the invention is preferably chosen from a double damping flywheel, a hydrodynamic torque converter and a friction disc. The invention also relates to a motor vehicle equipped with a torsion damping device according to the invention.

BRIEF DESCRIPTION OF THE FIGURES Other features and advantages of the invention will become apparent upon reading the detailed description and examining the appended drawing in which - FIGS. 1a, 3 and 4 represent, in perspective, a damping device detorsion according to different embodiments of the invention; FIG. 1b shows, in front view, the pendular damping device of the torsion damping device of FIG. - Figure 2 shows, in front view, a pendular damping deviceaccording to a variant of the invention.

In the various figures, identical references are used to designate identical or similar elements. Definitions

Unless otherwise indicated, "axially" means "parallel to the axis of rotation of the support"; - "radially" means "along a transverse axis intersecting the axis of rotation of the support"; - "transverse" means "in a plane perpendicular to the axis of rotation of the support"; - "angularly" or "circumferentially" means "around the axis of rotation of the support"; - "orthoradially" means "perpendicular to a radial direction and in a transverse plane".

By "transverse plane" is meant a plane perpendicular to the axis of rotation of the support.

By "radial plane" is meant a plane containing a radial axis and the X axis.

"Axial plane" means a plane containing the X axis. "The thickness" of a part refers to a dimension measured along the X axis.

The term "twist of the support about the X axis" means a deformation of the support by the joining of the parts of the support separated by notches by displacement of said parts in a transverse plane. Such a torsion therefore results from a closure, at least partial, of the notches.

"Motor vehicle" means not only passenger vehicles, but also industrial vehicles, including heavy goods vehicles, public transit vehicles or agricultural vehicles.

Unless otherwise indicated, the verbs "to comprise", "to present" or "to understand" must be interpreted in a broad manner, that is to say non-limiting.

detailed description

As shown in FIG. 1, a torsion damping device 8 according to the invention comprises a pendular damping device 10 and a phase shift washer 11.

The pendulum damping device comprises a support 12 adapted to move enrotation around an axis X and a plurality of pendulums 13, movable relative to the support12.

Each pendulum 13 comprises an oscillating mass 14 and one or more, for example two rolling bodies, not visible. Conventionally, each oscillating mass is mounted oscillating on the support by means of two rolling members, preferably rollers, which pass through a rolling window formed in the thickness of the support.

Each oscillating mass 14 conventionally comprises first and second flyweights 14i and 142, of generally planar shape, respectively extending opposite first and second major faces 12, and 122 of the support 12.

The first and second weights 14i and 142 are rigidly fixed to each other, preferably via a spacer, not visible. The spacer is sandwiched between the two flyweights and extends into the rolling window of the support.It defines the oscillating weight running track.

Each rolling member is thus supported on the one hand on a running track of the support, preferably defined by the inner contour of the rolling window of the support that the running member crosses and, on the other hand, on the track of oscillating mass bearing defined by the spacer of the oscillating mass.

The oscillating masses are preferably equiangularly distributed around the X axis. Preferably, their number is greater than 2 and / or less than 8. The device may in particular comprise three, five or seven oscillating masses. In the example shown in FIG. 1, the device comprises three oscillating masses uniformly distributed around the axis X.

The support 12 has a generally flat, generally annular shape. It has a radially inner annal 15i and a radially outer edge 15e, conventionally circular general shape, and first and second major faces 12i and 122ensensibly transverse.

The support 12 comprises fastening lugs 16 for attachment to the phase-shifter washer 11 by means of rivets 18. The fastening lugs 16 extend radially towards the X axis and are pierced with one or more fastening apertures 19, traversed each by unrivet 18.

The support is conventionally constituted by a cut sheet metal, generally enamier, with a thickness typically less than 10 mm.

Adjacent members, such as damping buffers and / or stops and / or guides for damping and / or limiting and / or guiding the oscillation movement of the oscillating masses, for example of polymer, can be fixed to this sheet.

According to the invention, the support 12 comprises at least one, preferably several notches20. In the embodiment of Figure 1, the support 12 has three notches.

A notch 20, preferably each notch 20, preferably radial, extends, preferably exclusively, between regions of the support traversed, in use, by two adjacent oscillating masses, 17a and 17b, when the damping device is observed along the X axis, as in Figure lb. These regions are called "pendulum regions".

Several notches 20a, 20b and 20c can be grouped between two adjoining pendulum regions 17a and 17b, as in FIGS. 3 and 4.

A notch is a notch which passes through the thickness of the support, that is to say which, substantially along its entire length, is open on each large face 12i and 122 of the support.

A notch is defined by first and second lateral edges 21a and 21b extending from an opening 22 through which the notch opens into the general plane of the support, preferably substantially radially, to a bottom 24, which defines the end notch opposite opening 22.

A notch does not necessarily emerge radially outwardly of the support. For example, in the embodiment of FIG. 3, the cuts 20a and 20b debouchentradially towards the X axis, that is to say towards the inside.

In FIG. 3, the two notches 20a and 20b extend on each side of the fixing lug 16, thus prolonging the fixing lug beyond the radially inner edge 15i of the support.

In the embodiment of FIG. 4, each group of notches separating two adjacent pendulum regions has two lateral notches 20a and 20b, emanating axially towards the X axis, and a central notch 20c, extending partially between the two lateral notches and opening radially outwards. The central cut is therefore provided in the bracket.

The shape and number of notches are not limited.

A notch allows an elastic approximation, in a transverse plane, of the two parts of the support 12a and 12b that it separates. To allow this approximation, a notch defines one or more bridges of material, which constitute hinge areas in which the material of the support will deform during the approximation.

When the notch 20 extends radially towards the axis X without radially exceeding the two parts of the support 12a and 12b, it defines a single material bridge between its bottom and the radially inner edge 15i of the support. Similarly, when the notch 20 extends radially away from the X axis without radially exceeding the two parts of the support 12a and 12b, it defines a single material bridge between its bottom and the radially inner edge 15e of the support.

When the cut 20 extends radially towards the X axis beyond the two parts of the support 12a and 12b, as in Figure 1, it defines several bridges of material, namely a material bridge 30i between its bottom and the edge radially interior 15i of the support, but aussideux bridges of lateral materials 302 and 303. All these material bridges, and the arrangement of the rivets, contribute to the stiffness of the bending imparted by the notch.

The material bridge or bridges are determined according to the desired stiffness. This amount is variable depending on the torsion damping device considered. However, simple tests make it possible to determine a suitable stiffness, and therefore the dimensions of the material bridge or bridges.

The length Z of the notch is preferably greater than 50 mm and / or less than 300 mm, preferably the length L is greater than the largest radial dimension r of the support in the pendulum regions which it separates.

The width / notch may be variable along its length.

In the embodiment of FIG. 3 for example, each notch has a width which increases progressively as one approaches the opening of the notch.

Preferably, the width of the notch is adapted so that the two parts of the support 12a and 12b which it separates can come into contact with each other before any degradation of the rivets. Preferably, however, it is large enough that the amplitude of the bringing together of the two parts of the support confers a high capacity of shock absorption. Preferably, the width at the zone of said contact is greater than 0.5 mm at and / or less than 4 mm. In a preferred embodiment, as in FIG. 1, this width of the notch is defined by at least one, in this case two lateral reflections 32a and 32b, protruding from the two lateral edges 21a and 21b of the notch, respectively.

As shown in Figure 2, such bulges are optional.

The maximum width of the notch is defined to minimize the weight of the support. In the embodiment of FIG. 1, the maximum width of the notch is also defined according to the desired stiffness. Preferably, the maximum width is greater than 10 mm and / or less than 30 mm.

The ratio LHmax of the length of a notch over its maximum width is preferably greater than 2, or even greater than 3, 4 or 5.

The operation flows directly from the above.

In use, pendulums oscillate under the effect of motor acyclisms. At the end of the stroke, the oscillating masses come into abutment with the support, which causes shocks on the support. The support transmits these shocks to the rivets.

According to the invention, the shock energy is partly used to bring one of the other adjacent parts of the support and separated by a notch. This approximation corresponds to a closure, at least partially, of the opening 22 of the notch. Due to the torsional flexibility provided by the notch, part of the impact energy is not transmitted to the rivets, which ensures their protection. Advantageously, the amount of energy transferred to the phasing washer through the rivets is also reduced.

Excessive approximation of adjacent support parts may, however, be detrimental to rivets. Preferably, when the impact exceeds a threshold level, the two side edges 21a and 21b of the notch come into contact with each other. The support then becomes rigid, which protects the rivets.

The rivets are thus protected by a support which has flexibility in bending up to a certain threshold, then becomes rigid again beyond.

At the end of impact, the notch opens again, due to the elasticity of the metal constituting the support, and resumes its original shape.

As is now clear, the invention provides a solution to limit the risk of rivets breaking.

The life of the pendulum damping device is increased.

Of course, the invention is not limited to the particular embodiments described above.

Claims (3)

1. Pendulum damping device, in particular for integration in a transmission chain of a motor vehicle, especially in a clutch, the device comprising: a support (12); a plurality of pendulums disposed about an axis X of rotation of the support, each pendulum (13) comprising an oscillating mass (14) and at least one unwinding member, interposed between said oscillating mass and the support so as to roll on the support and the oscillating mass during oscillation of the oscillating mass relative to the support, the device being characterized in that the support comprises a notch configured to give the support torsional flexibility about the X axis. 2. A pendulum damping device according to the preceding claim, whereinquaille 1'aillaille opens on a radially inner edge (15i) or a radiallyenextérieur edge (15e) of the support. Pendulum damping device according to any one of the preceding claims, in which the support comprises a fixing lug (19) intended for fixing the pendulum damping device to a torsion damping phase phasing washer, the notch extending, at least in part, into the fastening plate or delimiting, at least in part, an edge of said fastening tab. Pendulum damping device according to any one of the preceding claims, wherein said notch has a length (L) greater than the largest radial dimension (r) of the support regions adjacent to the notch and which, when the device is observed along the X axis, are covered by an oscillating mass. Pendulum damping device according to any one of the preceding claims, wherein said notch extends radially with respect to the axis X. 6. A pendular damping device according to any one of the preceding claims, wherein the support comprises several said notches, each notch separating, when the pendulum damping device is observed along the X axis, regions of the support supporting adjacent oscillating masses. 7. Pendulum damping device according to the immediately preceding claim, wherein the support comprises a group of several notches, identical or different, arranged, when the pendulum damping device is observed along the axis X, between regions of the support supporting adjoining oscillating masses. A torsion damping device having a damping device according to any one of the preceding claims, the pendulum damping device being fixed by means of rivets (18) to a phase shifter (11) of the damping device of torsion, said notch comprising aondond (24) and first and second lateral edges (21a; 21b) connected to said bottom, saidentry having a width such that the first and second lateral edges can be brought into contact with each other, without breaking a said rivet by torsion deupport about the axis X. 9. torsion damping device according to the immediately preceding claim, selected from a double damping flywheel, a hydrodynamic torque converter and a friction disc. 10. Motor vehicle equipped with a torsion damping device according to the immediately preceding claim.