Pendulum damping device
The pendulum damping device addresses radial drop and noise issues by offsetting pendulum masses and using holding members with elastic return members to maintain radial position and filter oscillations, enhancing performance and installation simplicity.
Patent Information
- Application Number
- FR2022013768
- Authority / Receiving Office
- FR · FR
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2022-12-19
- Publication Date
- 2025-01-03
- Estimated Expiration
- 2042-12-19
AI Technical Summary
Existing pendulum damping devices in motor vehicle transmission systems experience radial drop issues and noise when stopping and starting the engine due to the large radial dimension of the pendulum masses, which require complex installations to prevent radial falls.
The pendulum damping device features two pendulum masses offset circumferentially, with holding members and elastic return members to maintain radial position and filter torsional oscillations, using pins and stop profiles to prevent radial falls and reduce noise.
The solution effectively prevents radial falls and filters torsional oscillations, reducing noise and simplifying the installation process while maintaining efficient movement of the pendulum bodies.
Smart Images
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Abstract
Description
Title of the invention: Pendulum damping device
[0001] The present invention relates to a pendulum damping device, in particular for a motor vehicle transmission system.
[0002] In such an application, the pendulum damping device can be integrated into a torsion damping system of a clutch capable of selectively connecting the thermal engine to the gearbox, in order to filter vibrations due to engine acyclisms. Such a torsion damping system is for example a double damping flywheel.
[0003] This double damping flywheel is for example associated with a friction clutch disc or integrated into a transmission system comprising a double dry or wet clutch. In the latter case, the transmission system may or may not be integrated into a hybrid propulsion vehicle.
[0004] It is known to provide a pendulum damping device comprising:
[0005] - a mobile support rotating around an axis, and comprising a cooperating leg with elastic return organs,
[0006] - at least one pendulum body, movable relative to the support and comprising two pendulum masses respectively arranged axially on one side of the support, these two pendulum masses being secured to each other by a connecting member, and
[0007] - two rolling members guiding the movement of the pendulum body relative to to the support, each rolling member cooperating with a first rolling track secured to the support and with a second rolling track secured to the pendulum body and defined by the connecting member.
[0008] The connecting member(s) are received in one or more windows of the support which has a significant radial dimension since it receives: a rolling member, the connecting member defining the second rolling track on which this rolling member rolls, and since it must define a space accompanying the movement of the pendulum body. Due to this significant radial dimension, a significant radial drop height exists in this window for the pendulum masses when they are no longer centrifuged. This results in the appearance of noise during the stopping and starting phases of the engine.
[0009] In these known devices, the two pendulum masses of the same pendulum body are exactly superimposed so that the installation of members for holding this pendulum body to avoid these radial falls generates additional bulk or requires complex pendulum body shapes when several pendulum bodies follow one another circumferentially around the support.
[0010] There is a need to further improve such pendulum damping devices.
[0011] The invention aims to meet this need and achieves this, according to one of its aspects, using a pendulum damping device, comprising:
[0012] - a mobile support rotating around an axis,
[0013] - at least one pendulum body, movable relative to the support and comprising two pendulum masses respectively arranged axially on one side of the support, these two pendulum masses being secured to each other by at least one connecting member, and
[0014] - two rolling members guiding the movement of the pendulum body relative to to the support, each rolling member cooperating with a first rolling track secured to the support and with a second rolling track secured to the pendulum body and defined by the connecting member,
[0015] characterized in that the two pendulum masses of the pendulum body are offset relative to each other circumferentially.
[0016] As will be seen later, this circumferential offset relative to each other of the two pendulum masses of the pendulum body facilitates the installation of holding members making it possible to remedy the problem of radial fall mentioned previously.
[0017] The device is also characterized by the fact that it comprises a plurality of holding members carried by the support, each circumferential portion of one of the pendulum masses of the pendulum body extending circumferentially beyond the other pendulum mass of this pendulum body cooperating with one of these holding members,
[0018] each holding member being mounted movably on the support with the interposition of an elastic return member exerting a radial force,
[0019] each holding member comprising a pin projecting axially from one side of the support to cooperate with a stop profile of a circumferential portion of a pendulum mass to exert a radial force outwards on this pendulum mass, the stop profile having a curved shape, defining a concave fraction and / or a convex fraction.
[0020] Thus, for the pendulum body, two holding members are provided, each pendulum mass cooperating with one of these two holding members by means of its circumferential portion which extends circumferentially beyond the other pendulum mass of this pendulum body. Cooperation with these holding members makes it possible to remedy the aforementioned radial drop problem.
[0021] The cooperation of the pin with the stop profile makes it possible, when the pendulum body is no longer centrifuged, to prevent this pendulum body from undergoing a radial fall. Moreover, the aforementioned shape of the stop profile can make it possible not to hinder the movement of the corresponding pendulum body relative to the support, this movement making it possible to filter the torsional oscillations. In other words, the contact existing between the pin and the stop profile is compatible with this filtering. The shape of the stop profile is advantageously defined as a function of the path of the center of gravity of the pendulum body in its movement relative to the support to filter the torsional oscillations.
[0022] For the purposes of this application:
[0023] - “axially” means “parallel to the axis of rotation”,
[0024] - “radially” means “along a straight line belonging to a plane orthogonal to the axis of rotation and intersecting this axis of rotation”,
[0025] - “angularly” or “circumferentially” means “around the axis of rotation ",
[0026] - “orthoradially” means “perpendicular to a radial direction”,
[0027] - “solidary” means “rigidly coupled”,
[0028] - the angular sector defined by a pendulum mass from the axis of rotation of the support corresponds, in a plane perpendicular to this axis of rotation, to the maximum angle formed between two straight lines each passing through the axis of rotation of the support and each intersecting at least one circumferential end of this pendular mass,
[0029] - the excitation order of a heat engine is equal to the number of explosions of this engine per crankshaft revolution,
[0030] - the rest position of a pendulum body is that in which this body pendular body is centrifuged without being subjected to torsional oscillations from the acyclisms of the thermal engine. For this rest position, the value of the curvilinear abscissa of the center of gravity of the pendular body is zero, and
[0031] - an order value is filtered by the pendulum damping device when the ratio between: the amplitude of a torsional oscillation at this order value in the presence of the pendulum damping device, and this same amplitude in the absence of the pendulum damping device is less than 0.2, in particular less than 0.1.
[0032] Each pendulum mass of the pendulum body may extend between two circumferential ends over an angular sector measured from the axis of rotation of the support, the angular sector having the same value for these two pendulum masses. Thus these two pendulum masses may be identical structurally speaking, but be positioned circumferentially offset in the assembled state, that is to say once rigidly fixed to each other when the pendulum body is formed. The use of two identical pendulum masses to produce a pendulum body makes it possible to reduce costs.
[0033] When the two pendulum masses of a pendulum body extend over the same angular sector but are offset circumferentially from each other, the circumferential end of one of the two pendulum masses of the pendulum body may extend beyond the corresponding circumferential end of the other of the two pendulum masses of the pendulum body over an angular sector measured from the axis of rotation which is between 20 and 45°. The term "corresponding circumferential ends" refers to the ends of the two pendulum masses of the pendulum body in the trigonometric direction or the ends of the two pendulum masses of the pendulum body in the non-trigonometric direction.
[0034] Each pendulum mass thus has a circumferential portion extending circumferentially beyond the other pendulum mass of the pendulum body, up to the circumferential end of said pendulum mass.
[0035] In all of the above, the connecting member may be unique and comprise a single spacer defining the two second rolling tracks of the pendulum body.
[0036] Such a connecting member, as well as the two rolling members cooperating with the latter, can then be received in the same window provided in the support. Each first rolling track is for example defined by an edge of this window provided in the support, and each second rolling track is for example defined by an edge of this spacer of the connecting member.
[0037] Alternatively, the pendulum body may comprise two connecting members, each connecting member comprising a spacer. Each spacer may be received in a window provided in the support in which it is the only spacer received. In this case, each rolling member cooperates with a second rolling track defined by an edge of a spacer and with a first rolling track defined by an edge of the window in which this spacer is received.
[0038] Regardless of the number of connecting members that the pendulum body comprises, each connecting member may comprise means for fixing the spacer to each pendulum mass. The connecting member comprises, for example, a plurality of rivets assembling the spacer to the two pendulum masses. Alternatively, the spacer is welded to the two pendulum masses, screwed to these two pendulum masses, or even force-fitted into each of these two pendulum masses.
[0039] A portion of the contour of the spacer defines, for example, each second rolling track guiding the movement of a pendulum body. Alternatively, a coating may be deposited on this portion of the contour of the spacer to form one or more second rolling tracks.
[0040] In all of the above, each rolling member is for example a roller. Each rolling element is, for example, a roller made of steel. The roller can be hollow or solid. This roller may have only one diameter, along its entire longitudinal axis.
[0041] In all of the above, the stop profile may define, when moving from the circumferential end of the pendulum mass: first the convex fraction, then the concave fraction. While contact between the pin and the convex fraction may occur along the entire length of this convex fraction, no contact may exist between the pin and the concave fraction. Alternatively, only a zone of the concave fraction may come into contact with the pin, in particular the zone of the concave fraction immediately adjacent to the convex fraction.
[0042] The curved shape of the stop profile can be determined so that the radial position of the pin remains the same during the relative displacement of the pendulum mass with respect to this pin. Thus, the radial position of the holding member can remain constant during this relative displacement. When this holding member interacts with two circumferentially neighboring pendulum bodies, this maintenance of a constant radial position makes it possible to overcome the problem of radial fall of these two pendulum bodies, independently of their position with respect to the support. Although the point of contact between the pin and the stop profile changes, by sliding, the radial position of the pin remains the same.
[0043] In a particular example, the surface of the pin which cooperates with the stop profile can define a portion of a circle. In this example, the center of this portion of a circle advantageously maintains a constant radial position during the movement of the pendulum body relative to the support.
[0044] The stop profile may be provided in a contour of the circumferential portion of the pendulum mass, for example in a zone of the radially inner edge of this circumferential portion of the pendulum mass. Thus, the stop profile is not inside the pendulum mass but on a contour thereof.
[0045] Alternatively, the stop profile may be provided in an opening with a closed contour of the circumferential portion of the pendulum mass. The shape of this opening is then chosen so as not to hinder the movement of the pendulum body relative to the support in order to filter out torsional oscillations. The radially outer edge of this opening defines, for example, according to this second example of implementation, the stop profile and it thus retains the pendulum mass, and therefore the pendulum body, when this pendulum body is no longer centrifuged. According to this second example of implementation, the stop profile is inside the pendulum mass, and not on a contour thereof.
[0046] The elastic return member may be a spring, for example a helical spring.
[0047] Each holding member may comprise two axially opposite pins, each pin projecting axially from one side of the support to cooperate with a stop profile of a circumferential portion of a pendulum mass to exert a radial force outwards on this pendulum mass. When two pins are present, they can have exactly the same positioning, in a plane perpendicular to the axis of rotation of the support.
[0048] Axially speaking, the pins can extend on either side of the housing, without axial overlap with the housing.
[0049] With the exception of the pins, the holding member may be contained in an axial space delimited by two pendular masses each arranged on a respective side of the support. Each axial face of the holding member other than at the level of a pin comes, for example, directly opposite a pendular mass, the latter axially covering this holding member.
[0050] The holding member can, by its axial positioning, between two circumferential portions belonging respectively to two pendular masses extending respectively on one side of the support, play the role of a wedge, preventing by its thickness these two circumferential portions from coming together.
[0051] When the stop profile is provided in a zone of the radially inner edge of the circumferential portion of the pendulum mass, the zone of the circumferential portion of the pendulum mass which radially overlaps the convex fraction of the stop profile may have a minimum dimension, parallel to the radial direction at the center of gravity of the pendulum body, of between one and two times the thickness of the pendulum mass in said zone. This thickness of the pendulum mass in said zone may or may not be the same as at any point of the pendulum mass.
[0052] Such a pendulum mass may have a reduced size at the circumferential portions, which may reduce the amount of material overhanging the remainder of the pendulum mass. The presence of large radii at the junction of the circumferential portions with the remainder of the pendulum mass may also reduce the mechanical stresses at this junction.
[0053] “In radial overlap” means “in the extension along a radius which cuts the convex fraction of the stop profile”.
[0054] The area of the circumferential portion of the pendulum mass which radially overlaps the stop profile may have on its radially inner edge a maximum radial coordinate which is greater than the minimum radial coordinate on its radially outer edge.
[0055] Where appropriate, the axially pendulous mass on the same side of the support and which belongs to the circumferentially adjacent pendulous body may have an extension which comes radially beyond said circumferential portion, so as to to maintain sufficient mass on the scale of a pendulum body.
[0056] The holding member may be made from a single piece. Whether the holding member is made from a single piece or not, it may be made of plastic, for example polyamide. When the holding member is not made from a single piece, the pin(s) may be attached to the rest of the holding member.
[0057] The holding member and the elastic return member can be received in the same opening provided in the support.
[0058] The device may comprise a base fixed to the support and cooperating with the elastic return member and with the holding member. This base may be arranged in the opening in which the holding member and the elastic return member are received.
[0059] The base may comprise a fixing system on the support. This fixing system is for example in the form of two tabs extending respectively on each axial side of the support and allowing axial maintenance of the base on the support. These two tabs constitute for example the radially inner end of the base.
[0060] The base may comprise a guide rod for the elastic return member. This rod extends, for example, inside the elastic return member, the latter being in particular a helical spring.
[0061] The base may comprise two arms, each arm cooperating with a respective groove provided in the holding member to form a sliding connection between the base and the holding member. Thus, the base makes it possible to guide the movement of the holding member relative to the support, and thus the movement of the pendulum mass relative to the support. Each arm may comprise at its free end a return capable of cooperating with a surface of the holding member. This return may define a hook whose cooperation with the holding member forms a stop for the radial movement of the holding member relative to the base. This allows for the existence of a preload between the base and the holding member. The rod is for example circumferentially arranged between the two arms.
[0062] In all of the above, the pendulum damping device may comprise a plurality of pendulum bodies, in particular three pendulum bodies, succeeding one another circumferentially around the axis of rotation of the support, and each circumferential portion of a mass of a pendulum body extending circumferentially beyond the other pendulum mass of this pendulum body may have a zone circumferentially overlapping a pendulum mass of a circumferentially neighboring pendulum body.
[0063] In other words, the different pendulum bodies can be arranged on the support in such a way that each pendulum mass of a pendulum body has, circumferen- technically speaking:
[0064] - a portion circumferentially overlapping a portion of the other mass pendulum of the pendulum body to which it belongs, this other pendulum mass being arranged on the other side of the support;
[0065] - a circumferential portion extending circumferentially beyond the other pendular mass of the pendular body to which it belongs, and within which an area circumferentially overlaps a pendular mass arranged on the other side of the support and which belongs to the circumferentially neighboring pendular body.
[0066] In this case of partial circumferential overlap between two masses belonging respectively to circumferentially neighboring pendular bodies, each holding member can cooperate with two pendular masses belonging respectively to one of these two circumferentially neighboring pendular bodies. The holding members are thus shared, which makes it possible to reduce their number, and therefore the cost of the pendular damping device, since instead of having 2n for n pendular bodies, only n are necessary.
[0067] In particular, a holding member above may extend axially on each side of the support, cooperating on one side of the support with the stop profile formed in a pendulum mass of a pendulum body and cooperating on the other side of the support with the stop profile formed in a pendulum mass of the circumferentially neighboring pendulum body.
[0068] Alternatively, although there is partial circumferential overlap between two masses belonging respectively to circumferentially neighboring pendular bodies, each holding member may cooperate with only one pendular body. In this case, two distinct radially and / or circumferentially offset openings may be provided in each portion of the support at which there is partial circumferential overlap between pendular masses belonging to circumferentially neighboring pendular bodies. These two offset openings may circumferentially overlap in whole or in part. Alternatively, these two holding members may be received in the same opening provided in the support.
[0069] Whatever the variant considered, this opening or these two openings may be distinct from the aforementioned windows and be arranged circumferentially between two windows provided in the support, one of these two windows being associated with a pendulum body and the other of these two windows being associated with the circumferentially neighboring pendulum body.
[0070] In all of the above, the support may comprise at least one leg, in particular two diametrically opposed legs, this leg being capable of cooperating with elastic return members for filtering torsional oscillations.
[0071] The tab may define the portion of the support radially furthest from the axis of rotation of the support.
[0072] In all of the above, the support may be made from a single piece, for example being entirely metallic.
[0073] In all of the above, in the pendulum damping device, all the first rolling tracks secured to the support may have exactly the same shape between them and / or all the second rolling tracks secured to the pendulum body may have exactly the same shape between them.
[0074] In all of the above, the first and second rolling tracks may have shapes chosen so that the pendulum body is moved relative to the support both in translation around a fictitious axis parallel to the axis of rotation of the support, and also in rotation on itself, in particular in rotation around its center of gravity.
[0075] The invention also relates, according to another of its aspects, to a transmission system for a motor vehicle, the component being in particular a double damping flywheel, a hydrodynamic torque converter, a flywheel secured to the crankshaft, a double dry or wet clutch, a single wet clutch, a hybrid powertrain component, or a friction disc, comprising a pendulum damping device as defined above.
[0076] The component is for example a double damping flywheel, and it comprises:
[0077] - the above pendulum damping device, with the aforementioned lug, and
[0078] - a plurality of elastic return members, the tab interacting with two members elastic recall.
[0079] Two diametrically opposed legs may be provided, as mentioned above.
[0080] Each elastic return member can be formed by a single spring or by several springs, for example by two concentric springs of different stiffness. Each spring can be a straight spring or a curved spring.
[0081] This double shock absorber flywheel can have:
[0082] - a primary flywheel capable of being rigidly fixed, if necessary via a plate flexible, to the crankshaft of the thermal engine, and
[0083] - a secondary flywheel capable of being fixed at the input of a clutch or a double clutch. The support for the pendulum damping device is then part of the secondary flywheel.
[0084] The primary flywheel is capable of being secured to a crankshaft, which means that it can be permanently secured to the crankshaft. This securing of the primary component to the crankshaft is then different from that which would occur selectively via a clutch, for example.
[0085] The secondary flywheel may further comprise a hub. This hub may comprise splines, in order to be fitted onto a gearbox input shaft or onto an input shaft of a double clutch, dry or wet.
[0086] The invention also relates, according to another of its aspects, to a transmission system, in particular for a hybrid vehicle, comprising:
[0087] - the above component, and
[0088] - a double clutch, dry or wet, receiving the torque output from this component.
[0089] The transmission system may also comprise:
[0090] - a gearbox, comprising gears, defining gear ratios, and
[0091] - a front axle and a rear axle.
[0092] The invention also relates, according to another of its aspects, to a hybrid vehicle powertrain, comprising:
[0093] - the above transmission system, and
[0094] - a rotating electric propulsion machine, the shaft of the electric machine rotating being integral in rotation:
[0095] - of an input shaft of the gearbox, or
[0096] - of the gearbox output shaft, or
[0097] - of idle gears of the gearbox, or
[0098] - of the front axle or the rear axle, or
[0099] - of the crankshaft of the vehicle's thermal engine,
[0100] The rotating electrical machine has, for example, a nominal supply voltage of 48V, or a nominal supply voltage greater than 200V, in particular 300V, in particular 800V, in particular 1000V.
[0101] The invention may be better understood by reading the following description of non-limiting examples and by examining the attached drawing in which:
[0102] [Fig-1] represents a pendulum damping device for double damping flywheel with a pendulum damping device according to the invention,,
[0103] [Fig.2] represents a part of a pendulum damping device according to a first embodiment,
[0104] [Fig.3] is a detail of [Fig.2],
[0105] [Fig.4] is a sectional view along AA of [Fig.3],
[0106] [Fig.5] is a sectional view along BB of [Fig.4]
[0107] [Fig.6] is a view similar to [Fig.3] showing several successive positions of a pendulum mass in its displacement relative to the support, and
[0108] [Fig.7] is a view similar to [Fig.3] of another embodiment of pendulum bodies
[0109] [Fig.l] shows a pendulum damping device 1 for a double damping flywheel. This double damping flywheel is for example intended to be associated with a double wet clutch and / or to be integrated into a powertrain hybrid vehicle.
[0110] The double damping flywheel comprises, in a known manner, a primary flywheel and a secondary flywheel.
[0111] The primary flywheel may comprise: a hub, a flexplate, and a starter ring gear. This primary flywheel is capable of being fixed to the crankshaft of a thermal engine via screws or rivets. The thermal engine is, for example, three or four cylinder.
[0112] The secondary flywheel may comprise: a hub having grooves allowing it to be mounted on a shaft, a flange 2, also called a “sail”, and fixed via rivets received in holes made in the sail on the hub, and pendulum bodies 3, each pendulum body comprising two pendulum masses 5 respectively arranged axially on one side 4 of the sail 2, the latter playing the role of support for the pendulum bodies.
[0113] The double damping flywheel also comprises elastic return members limiting the rotation of the secondary flywheel relative to the primary flywheel around the axis of rotation X. Two springs are provided here and these may be curved springs.
[0114] As can be seen in [Fig. 1], the support 2 comprises in this example two legs 19 each defining a radial extension and each of these legs 19 comes into contact with a spring when the secondary flywheel moves in rotation around the X axis relative to the primary flywheel. The two legs 19 are here diametrically opposed.
[0115] In [Fig. 1], the pendulum damping device 1 is at rest, that is to say that it does not filter the torsional oscillations due to the acyclisms of the thermal engine.
[0116] In the example of [Fig. 1], three pendulum bodies 3 are provided, being distributed uniformly around the circumference of the X axis.
[0117] As can be seen in [Fig. 1], each pendulum body 3 comprises in this example:
[0118] - two pendulum masses 5, each pendulum mass 5 extending axially res respectively on one side 4 of the support 2, and
[0119] - a single connecting member 6 securing the two pendulum masses 5 of this body pendulum.
[0120] In other examples, two separate connecting members 6 may be provided to secure the two pendulum masses 5 of the same pendulum body 3.
[0121] Each pendulum mass 5 of a pendulum body 3 extends in the example described between two circumferential ends over an angular sector measured from the axis of rotation X of the support 2 which is equal, from one of these pendulum masses 5 to the other.
[0122] In the example of [Fig.l], each connecting member 6 comprises a single brace 7 rigidly fixed between each pendulum mass 5 of a pendulum body by means of rivets 9 visible in figures 1 and 2 which are received in holes made in the brace 7, so as to secure these two pendulum masses 5 together.
[0123] Each spacer 7 extends partly into a window 8 formed in the support 2. In the example considered, the window 8 defines an empty space inside the support 2, this window being delimited by a closed contour.
[0124] The device 1 also comprises, in the example considered, rolling members 11 guiding the movement of the pendulum bodies 3 relative to the support 2. The rolling members 11 are here rollers, as will be seen later. In the example of the figures, each roller retains a substantially constant diameter over its entire length.
[0125] As seen in [Fig. 2], the device 1 may also comprise stop damping members 22 capable of coming simultaneously into contact with a spacer 7 and with the support 2 in certain relative positions of the support 2 and the pendulum masses 5, such as coming into contact at the end of a maximum displacement from the rest position to filter a torsional oscillation or during a radial fall of the pendulum body. Each stop damping member 22 is for example integral with a pendulum body, being mounted on this pendulum body and arranged so as to be interposed radially between the spacer 7 of this pendulum body 3 and the contour of the window 8. Each stop damping member 22 comprises for example one or more parts fixed on the spacer 7.
[0126] In the example described, the movement relative to the support 2 of each pendulum body is guided by two rolling members 11.
[0127] As can be seen in [Fig.4], each rolling member 11 cooperates by rolling with a single first rolling track 12 secured to the support 2, and with a single second rolling track 13 secured to the pendular body 3 to guide the movement of the pendular body in translation around a fictitious axis parallel to the axis of rotation X of the support 2 and, where appropriate, in rotation, in particular in rotation around the center of gravity of said pendular body 3.
[0128] In the example considered, each second rolling track 13 is formed by a portion of the radially outer edge of the spacer 7 which thus defines, via two different portions of its radially outer edge, the second rolling tracks 13 of the pendulum body.
[0129] Each first rolling track 12 is in the example considered defined by a part of the contour of the window 8 in which the spacer 7 is received. In the example considered, two different portions of the radially outer edge of the contour thus define the two first rolling tracks 12 associated with the pendular body.
[0130] Each first rolling track 12 is here arranged radially opposite a second rolling track 13, so that the same lateral rolling surface of a rolling member 11 rolls alternately on the first rolling track 12 and on the second rolling track 13. The lateral rolling surface of the rolling member is here a cylinder of constant radius.
[0131] In the examples of the figures, axial interposition pieces between the pendulum body 3 and the support 2, also called “pads”, are provided. One or more pads are for example carried in a fixed manner by each pendulum mass 5, on their face opposite the support 2. The fixing of these pads is done for example via projections 17 received in openings made in the pendulum masses 5.
[0132] According to the embodiment which will now be described, it can be seen that for each pendulum body 3, the two pendulum masses 5 are offset relative to each other circumferentially.
[0133] Thus, each pendular mass 5 of a pendular body 3 presents, in the described modes:
[0134] - a portion 25 circumferentially overlapping a portion 25 of the other mass pendular 5 of the pendular body 3 to which it belongs, this other pendular mass being arranged on the other side 4 of the support 2,
[0135] - a circumferential portion 26 extending circumferentially beyond the other pendulum mass 5 of the pendulum body to which it belongs, and within which a zone 27 circumferentially overlaps a pendulum mass 5 arranged on the other side of the support and which belongs to the circumferentially neighboring pendulum body 3.
[0136] The circumferential offset between two pendulum masses 5 belonging to the same pendulum body 3 once formed, measured as being the value of the angular sector defined from the axis of rotation X of the support between:
[0137] - the straight line passing through the axis of rotation X and through the radially outer end of a circumferential edge of one of these pendulum masses 5, and
[0138] - the straight line passing through the axis of rotation X and through the radially outer end of the corresponding circumferential edge of the other of these pendulum masses 5,
[0139] is here between 5 and 45°, for example between 20° and 45°.
[0140] We will now describe in more detail with reference to Figures 2 to 6 a mode of embodiment of the invention in which holding members 30 making it possible to remedy the problem of radial fall of the pendulum bodies 3 are present.
[0141] Each pendulum body 3 has, near one of its circumferential ends, a holding member 30. One of these holding members cooperates here with the circumferential portion 26 of a pendulum mass 5 and the other of these holding members cooperates with the circumferential portion 26 of the other pendulum mass 5 of this same pendulum body 3.
[0142] Each holding member 30 is carried by the support 2. It is also noted that, according to this mode, as specifically described with reference to FIGS. 2 to 5, each holding member 30 is common to two circumferentially neighboring pendular bodies. As can be seen in [Fig. 4], each holding member 30 can act as a wedge between two circumferential portions 26 of pendular masses 5 each belonging to two circumferentially neighboring pendular bodies.
[0143] In the described embodiment, the mounting of each holding member 30 on the support 2 is not fixed, but is done via the interposition of an elastic return member 31 exerting a force tending to move the holding member 30 radially outwards. This elastic return member is here a helical spring 31. Each holding member 30 here comprises a housing 33 cooperating with the elastic return member 31 and it comprises a pin 34 projecting axially from one side of the support 2 to cooperate with a stop profile 36 of the circumferential portion 26 of a pendular mass 5 to exert a radial force outwards on this pendular mass. The holding member 30 is here made in a single piece, being here made of plastic material. As can be seen, a part of the elastic return member 31 is received in the housing 33.
[0144] In the example considered, each pin 34 cooperates with a stop profile 36 which is defined by a zone of the radially inner edge 37 of the circumferential portion 26 of the pendulum mass 5. In a variant not shown, the stop profile 36 is arranged inside the circumferential portion 26, and not on a contour thereof.
[0145] The stop profile 36 here has a curved shape. This stop profile 36 here combines, when moving from the circumferential end of the pendulum mass 5, a convex fraction 38, then a concave fraction 39. It can also be seen in the figures that the pin 34 cooperates with the stop profile 36 via a surface which is a circular portion.
[0146] In the example of the figures, each holding member 30 comprises two axially opposite pins 34. Each pin 34 projects axially from one side of the support 2 to cooperate with a stop profile 36 of a circumferential portion 26 of a pendulum mass to exert a radial force outwards on this pendulum mass. In the example considered, the pin 34 comes into contact with the convex fraction 38 all along the latter but does not come into contact with the concave fraction 39, or alternatively with only the zone of this concave fraction 39 immediately adjacent to the convex fraction 38.
[0147] As can be seen in [Fig.4], when two pins 34 are present, they can have exactly the same positioning, in a plane perpendicular to the axis of rotation of the support.
[0148] Still in the example considered and as shown in [Fig.4], axially speaking, the pins 34 can extend on either side of the housing 33, without axial overlap with this housing 33.
[0149] As can be seen in [Fig.5], the holding member 30 and the elastic return member 31 can be received in the same opening 40 provided in the support 2. This opening 40 here has a radially elongated shape.
[0150] A base 45 cooperating with the holding member 30 is also provided in the example considered. This base 45 is fixed on the support 2 and it also cooperates with the elastic return member 31, the latter being functionally interposed between the base 45 and the holding member 30. This base 45 is here also arranged in the opening 40 which already receives the holding member 30 and the elastic return member 31, as already mentioned.
[0151] In the example considered, the base 45 comprises a fixing system on the support 2. This fixing system is presented here in the form of two tabs 47 extending respectively on each axial side of the support and constituting here the radially inner end of the base 45.
[0152] The base 45 comprises a guide rod 50 for the elastic return member 31. This rod 50 extends inside the helical spring 31. The base 45 comprises two arms 52, each arm 52 cooperating with a respective groove 55 formed in the holding member 30 to form a sliding connection between the base 45 and the holding member 30. Each arm 52 may comprise at its free end a return 53 capable of cooperating with a surface 54 of the holding member. This return 53 here defines a hook whose cooperation with the surface 54 of the holding member which defines a recess forms a stop for the radial displacement of the holding member relative to the base.
[0153] As can be seen in [Fig.5], the rod 50 is circumferentially arranged between the two arms 52.
[0154] The presence of a holding member 30 as described simply allows that, when the two circumferentially neighboring pendulum bodies cooperating with the holding member 30 are no longer centrifuged, each pin 34, under the effect of the helical spring 31, presses on the stop profile 36 of the corresponding pendulum mass 5 radially outwards.
[0155] As can be seen in [Fig. 6], the curved shape of the stop profile 36 is here determined so that the radial position of the pin 34 remains the same during the relative movement of the pendulum mass with respect to this pin. Thus, whether the pendulum mass 5 occupies position A, position B, or position C during its movement, the radial position of the holding member 30 remains constant, although the contact point between pin 34 and stop profile 36 changes, by sliding and that the radial position of this contact point evolves. Thus, the compression of the elastic return member 31 interacting with the elastic return member remains the same during this movement.
[0156] We will now describe with reference to [Fig.7] another example of a pendulum body 3 with stop profiles 36 allowing radial retention of the pin 34 during movement relative to the support 2. It is observed, in comparison with the example described with reference to the preceding figures, that the circumferential portion 26 is thinned. This circumferential portion always defines, on its radially inner edge 37, the stop profile 36 with the convex fraction 38 and the concave fraction 39. The thinning can for example be reflected in the fact that, a maximum dimension D measured parallel to the radial direction at the center of gravity of the pendulum body being greater than a minimum dimension d, also measured parallel to the radial direction at the center of gravity of the pendulum body, this minimum dimension d is between 1 and 2 times the thickness of this circumferential portion 26 of the pendulum mass, this thickness being measured axially.
[0157] In addition to being thinned, the circumferential portion 26 may have a curved shape which may be characterized by the fact that its radially inner edge 37 has a maximum radial coordinate greater than the minimum radial coordinate of its radially outer edge 35.
[0158] Furthermore, as shown in [Fig.7], the circumferential end of the pendulum mass 5 of the circumferentially adjacent pendulum body and arranged axially opposite the same side of the support 2 may comprise an extension 70 which comes radially beyond the circumferential portion 26. This extension 70 is devoid of a stop profile, not cooperating with a holding member 30. This extension 70 may have an edge opposite the circumferential portion 26 which is dimensioned so as to guarantee the existence of a clearance making it possible not to come into contact with this circumferential portion.
[0159] All the pendulum masses 5 of the device may have circumferential portions 26 and extensions 70 as shown in [Fig.7].
[0160] The invention is not limited to the embodiments which have just been described.
Claims
Claims
1. Pendulum damping device (1), comprising: - a support (2) movable in rotation about an axis (X), - at least one pendulum body (3), movable relative to the support (2) and comprising two pendulum masses (5) respectively arranged axially on one side (4) of the support (2), these two pendulum masses (5) being secured to each other by at least one connecting member (6), and - two rolling members (11) guiding the movement of the pendulum body relative to the support (2), each rolling member (11) cooperating with a first rolling track (12) secured to the support (2) and with a second rolling track (13) secured to the pendulum body and defined by the connecting member, device characterized by the fact that the two pendulum masses (5) of the pendulum body (3) are offset relative to each other circumferentially, and by the the fact that it comprises a plurality of holding members (30) carried by the support (2),each circumferential portion (26) of one of the pendulum masses (5) of the pendulum body (3) extending circumferentially beyond the other pendulum mass (5) of this pendulum body (3) cooperating with one of these holding members (30), each holding member (30) being mounted movably on the support (2) with the interposition of an elastic return member (31) exerting a radial force, each holding member (30) comprising a pin (34) projecting axially from one side of the support to cooperate with a stop profile (36) of a circumferential portion (26) of a pendulum mass to exert a radial force outwards on this pendulum mass (5), the stop profile (36) having a curved shape, defining a concave fraction (39) and / or a convex fraction (38).,
2. Device according to claim 1, the stop profile (36) defining, when moving from the circumferential end of the pendulum mass (5) the convex fraction (38), then the concave fraction (39).
3. Device according to claim 1 or 2, the curved shape of the stop profile (36) being determined so that the radial position of the pin (34) remains the same during the relative movement of the pendulum mass (5) with respect to this pin (34).
4. Device according to any one of the preceding claims, the surface of the pin (34) cooperating with the stop profile (36) defining a portion of a circle.
5. Device according to any one of the preceding claims, each holding member (30) comprising two axially opposite pins (34), each pin (34) projecting axially from one side of the support (2) to cooperate with a stop profile (36) of a circumferential portion (26) of a pendulum mass to exert a radial force outwards on this pendulum mass.
6. Device according to any one of the preceding claims, the stop profile being provided in an area of the radially inner edge of the circumferential portion (26) of the pendulum mass (5).
7. Device according to claim 6, the area of the circumferential portion of the pendulum mass (5) which radially overlaps the stop profile (26) having on its radially inner edge (37) a maximum radial coordinate which is greater than the minimum radial coordinate on its radially outer edge (35)
8. Device according to any one of the preceding claims, the connecting member (6) being unique and comprising a single spacer (7) defining the two second rolling tracks (13) of the pendulum body (3).
9. Device according to any one of the preceding claims, comprising a plurality of pendulum bodies (3), in particular three pendulum bodies, succeeding one another circumferentially around the axis (X) of rotation of the support (2), each circumferential portion (26) of a mass (5) of a pendulum body (3) extending circumferentially beyond the other pendulum mass (5) of this pendulum body (3) having a zone (27) circumferentially overlapping a pendulum mass (5) of a circumferentially neighboring pendulum body (3).
10. Device according to any one of the preceding claims, the support (2) comprising at least one leg (19), in particular two diametrically opposed legs (19), this leg (19) being capable of cooperating with elastic return members for filtering torsional oscillations.
11. Component for a transmission system of a motor vehicle, the component being in particular a double damping flywheel, a hydrodynamic torque converter, a flywheel integral with the crankshaft, a double dry or wet clutch, a single clutch wet, a hybrid powertrain component, or a friction disc, comprising a pendulum damping device (1) according to any one of the preceding claims
12. Component according to claim 11, being a double damping flywheel, and comprising: - the pendulum damping device (1) according to claim 10, and - a plurality of elastic return members for filtering torsional oscillations, the lug (19) interacting with two of these elastic return members.