Skeletal primary flywheel covered with sealing shells

Abstract

Skeletal primary flywheel covered with sealing shells. The invention relates to a skeletal inertia mass (10) and a skeletal cover (20), partially delimiting an internal volume (V0) for a damping system and intended to form a cage-shaped primary flywheel (2), the sealing of the lubricant contained in the internal volume being ensured by sealing shells (13, 23) covering the skeletons (11, 21) of the inertia mass (10) and the cover (20). Figure for the abstract: Figure 2

Description

Title of the invention: Skeletal primary flywheel covered with sealing shells

[0001] The invention relates to a skeletal flywheel, in the form of a sealed cage, in particular within a double damping flywheel for powertrain systems. The invention also relates to: a skeletal flywheel, a skeletal cover, a skeletal primary flywheel formed from the latter, and a double damping flywheel comprising the latter. The invention also relates to a method for manufacturing such a flywheel.

[0002] Internal combustion engines do not generate a constant torque and exhibit acyclisms caused by the successive explosions in their cylinders. These acyclisms generate vibrations which are likely to be transmitted to the gearbox and thus cause unwanted shocks, noise and sound pollution.

[0003] In order to reduce these undesirable effects and improve the driving comfort of motor vehicles, motor vehicle transmissions are equipped with a double damping flywheel. A double damping flywheel comprises a primary flywheel intended to be fixed at the end of a drive shaft, a secondary flywheel, coaxial with the primary flywheel, and a damping system formed for example of elastic members between the primary flywheel and the secondary flywheel to transmit a torque and dampen rotational acyclisms between the flywheels.

[0004] To ensure the proper functioning of the double damping flywheel, part of its damping system must be immersed in a lubricant retained in an internal volume of the double damping flywheel.

[0005] This internal volume which contains the lubricant, called the annular chamber, must necessarily be watertight so that the lubricant does not spread into the rest of the powertrain, in particular onto the clutch.

[0006] Sealing is ensured by the solid primary inertia mass having a radially oriented annular portion, which is provided on the inner periphery with a hub for fixing the primary flywheel to the nose of the drive shaft, and on the outer periphery with a sealed cylindrical skirt of axial orientation. A sealed annular cover is then laser welded against the cylindrical skirt. This design is nevertheless complex for the following reasons:

[0007] The size and mass of a flywheel must be adapted to the operating characteristics of the car manufacturer's engine. However, even small weight changes can chip or amplify the vibrations mentioned above and make them more noticeable. In addition, the parts to be superimposed for the laser welds must be thickened. The thick and misshapen laser weld bead is unsatisfactory.

[0008] The impact of CO2 linked to the high-power laser welding required is very significant, to correctly weld thick steel parts. This results in the excess weight of the double damping flywheels currently on the market and an increase in CO2. The cost of steel and stamping is also significant. Their mass production also reveals recurring quality problems causing rejects and grease leaks.

[0009] The aim of the invention is to improve the components of the primary flywheel and to solve at least in part the mentioned drawbacks of the prior art, by providing a simple, effective and economical solution to this problem. In particular, it is sought to improve the performance of the vehicle, to drastically reduce CO2 emissions, the mass of the primary flywheel, by finding the best possible compromise between: the reduction of the corresponding inertia, the preservation of the damping and sealing functions.

[0010] For this purpose, the invention proposes, according to a first aspect, an inertia part of a flywheel, in particular an inertia mass or a cover for a flywheel, in particular for a double damping flywheel, with an axis of revolution X, intended to partly contain a damping system inside an internal volume delimited in part by at least one skeleton extending on one side of the damping system.

[0011] Thus each inertial part (inertial mass, cover) is reduced to a minimum, hollowed out in the form of a skeleton, by producing a series of perforated openings of dimensions adapted to contain said damping system.

[0012] The term "skeleton" of an inertial part means a framework of material (purely functional) of thinner thickness, removed from any non-functional mass, performing only the unique functions of the part.

[0013] Thus, this new skeletal form makes it possible to both reduce the weight, while retaining its structural and inertia functions, and while retaining the centrifugation constraints and the stopping loads of the springs.

[0014] In addition, each inertia part can be intended for a main function, which is specific to it and without weighing it down. By thus reducing the need for inertia mass and the cover, the need for material and the CO2 emissions associated with manufacturing and operation on the vehicle are reduced. This results in a significant economic and ecological gain.

[0015] This first aspect of the invention may have one or other of the characteristics described below combined with each other or taken independently of each other:

[0016] - The same skeleton can have at least one thickness between 3 and 10 mm, and in particular variations in thickness, the thickest portion of which is provided on the external periphery of the skeleton;

[0017] - The skeleton may be provided with force or anchor points around which are angularly distributed the openwork openings or between which the openwork openings are angularly distributed. The resistance of the skeleton which ensures the fixing and which thus undergoes the most significant constraints is reinforced in places;

[0018] - Strength or anchor points may be at least distributed along the edge external of the skeleton;

[0019] - Strength or anchor points can be at least distributed over an area central skeleton;

[0020] - The force points can be distributed angularly around the X axis, according to a regular or uniform distribution, for example in relation to anchor points;

[0021] - The series of openwork openings can be made by cutting out material, from of a flat piece preferably made of sheet metal or steel. At least some openwork openings can be made in the form of:

[0022] - symmetrical patterns, preferably along an axis of symmetry perpendicular to the X axis of revolution. Preferably each axis of symmetry passes through one of the force or anchor points of said skeleton;

[0023] - notches preferably made from a radial portion of said skeleton. Thus the need for material is reduced, the radial wall is no longer annular but angularly discontinuous;

[0024] - windows preferably made from an axial portion or cylindrical skirt of said skeleton;

[0025] - The openwork openings can be regularly distributed around the X axis, in order not to generate unbalance.

[0026] - The openwork openings can be of dimensions adapted to contain the system damping, for example damping springs. The series of openwork openings may be provided over at least 40% of a total area of ​​the part forming the skeleton, in particular over half or more of the initial area of ​​the part;

[0027] - The greater the space provided for the openwork openings, the more space is allowed for the engine to spend less energy to make it turn. The engine can then transmit more energy to the skeleton to make it move forward. Hence, better acceleration associated with the flywheel;

[0028] - According to one embodiment, each inertia part (the inertia mass and / or the cover) may further comprise a sealing shell covering the skeleton, in particular the perforated openings of the skeleton, so as to contain lubricant which, if necessary, would escape from the perforated openings.

[0029] Thus, each part is dedicated to a main function which is specific to it. The functions of container, structural resistance (skeleton) vs. sealing (shell) are carried out separately;

[0030] - A shell can be made from a material chosen from steel, aluminum, plastic aluminum alloys, magnesium, magnesium alloys, tungsten and tungsten alloys.

[0031] - In particular, the material of the shell can be chosen from the following list: stainless steel, plastic or polymer materials, aluminum, materials produced by overmolding;

[0032] - The sealing shell can be fixedly mounted to the skeleton which it covers, for example by means of:

[0033] - of a deformation of material of the shell, preferably on the basis of the or openwork skeleton openings;

[0034] - mounting holes, receiving the sealing shell, which are formed among the series of openwork openings.

[0035] - of rivets, spacers and / or extruded pins, which are formed for example from the skeleton.

[0036] - The sealing shell can be fixedly mounted to the skeleton which it covers, For example

[0037] - by plating, for example in the form of an imprint, with said skeleton.

[0038] Thus, the imprint can follow the curvature of the skeleton, as well as the outline of openwork openings.

[0039] The risks of scrap and assembly errors are reduced. The risks of leaks are limited; and / or

[0040] - by cooperation of deformed shapes, preferably tubular, called caps of material, of the shell with openwork openings of the skeleton. The number of fixing components is limited. The tubular elongation of the caps provides additional support through the skeleton; and / or

[0041] - by mounting holes formed among the series of perforated openings of the skeleton, from which rivets, spacers or extruded pins connecting the shell are passed.

[0042] The invention also proposes, according to a second aspect, a flywheel in the form of a cage configured to contain the damping system and to introduce a force into the damping system, produced by assembling an inertial mass and a cover, preferably according to an assembly connection.

[0043] The inertia mass of said flywheel may be according to the first aspect of the invention. Alternatively or additionally, the cover of said flywheel may be according to the first aspect of the invention.

[0044] This assembly connection of said skeletons is preferably angularly discontinuous.

[0045] This second aspect of the invention may have one or other of the characteristics described below combined with each other or taken independently of each other:

[0046] - The skeleton of the primary mass may be of a different thickness from that of the skeleton of the cover. The thickness of the skeleton of the primary mass may be greater than that of the skeleton of the cover;

[0047] - The skeleton of the primary mass can subsequently be called "first skeleton”. The (first) skeleton of the inertial mass can be covered by a first sealing shell.

[0048] - The skeleton of the cover can be called hereinafter "second skeleton". The (second) skeleton of the cover can be covered by a second sealing shell;

[0049] - The assembly connection can be covered by the second sealing shell;

[0050] - The assembly connection may be exempt from welding. Alternatively, the connection assembly can include additional fine welding, with a reduction to 20% of the current laser welding power. The (virtually) elimination of complex welding allows for significant elimination of associated CO2 emissions.

[0051] - The assembly connection may be a connection fitted to a skeleton of the primary mass in a skeleton of the cover. This simplifies mass production. The press-fit connection can be formed by means of a radial wall extending along the outer circumference of the skeleton. The outer radial wall is discontinuous around the X axis. The portions of the discontinuous radial wall can form stop pins;

[0052] - The press-fit connection may be formed by means of stop pins passing through the skeleton of the lid.

[0053] - The stop pins may be made from the material of the mass skeleton inertia. The press-fit stop pins are flat, preferably stamped. This reduces the size and material requirements;

[0054] - For example, the press-in stop pins can be welded to their end, for example a weld with added material, to complete the fixing of the cover fitted onto the inertia mass;

[0055] - In another example, the press-fit stop pins may be provided at their end of deformable retaining pins, to complete the fixing of the cover fitted onto the inertia mass. In this way, any additional complex welding operation is eliminated;

[0056] - The skeleton of the primary mass can be equipped with a peri-annular rim spherical, preferably from which stop pins extend for the press-fit connection, to facilitate assembly operations and reinforce the mechanical strength of the joint. Such a peripheral shoulder or annular rim is sized to receive part of the damping system, for example damping springs;

[0057] - According to one embodiment of the invention, the sealing shell of the cover may include at least one fold of centering material on the internal periphery, for example creating a centering collar relative to the internal periphery of the cover. This simplifies their assembly;

[0058] - The sealing shells can be fixedly mounted between them, and in particular sealed together:

[0059] - by overmolding material from one end of a shell onto the end of the other shell; or

[0060] - by crimping or double crimping, preferably hot, with exchange of heat; or

[0061] - by brace of the ends, preferably along the X axis. Which also limits the grease leaks; and / or

[0062] - by cooperation of shapes of the external ends, in particular folds of material shells inside each other. For example, by a double seam or triple seam, to seal the shells together, locking them mechanically at their ends, for a flawless seal;

[0063] The folds of material may be equal to or greater than three in number, per sealing shell;

[0064] The folds of material can be made by folding, in particular thin sheet metal, from their external periphery;

[0065] - by continuous or discontinuous welding, for example by partial welding, via welding points or weld beads. For example, by electrode welding (seam weld in English), or by arc or laser welding or by electrical resistance. Therefore, the two welded shells can be of different nature and thickness, maintained under pressure and placed for example between two electrodes.

[0066] - According to one embodiment, the flywheel may further comprise a target in the form of an annular crown intended to be arranged opposite a sensor capable of delivering a signal representative of the angular position and / or the speed of the target. Advantageously, the target can be mounted bearing on the sealing shell of the inertia mass, preferably mounted housed from a recess in the first shell; Alternatively, the target can be mounted bearing on the sealing shell of the cover, preferably mounted housed from a recess in the second shell; Said recess of a shell may be of shapes complementary to that of the target, for example of truncated cone shapes.

[0067] The invention also proposes, according to a third aspect, a double damping flywheel for a mobility device, comprising: a flywheel called primary according to the second aspect of the invention, configured to introduce a force into the double damping flywheel; a flywheel called secondary, configured to deliver the force to a clutch. The flywheel and the flywheel delimit at least said internal volume in which are contained: a lubricant and at least in part a damping system arranged on a force transmission path between the primary flywheel and the secondary flywheel. The clutch can be of the wet or dry type;

[0068] - The damping system may be provided with at least one series of members elastics;

[0069] - The damping system may be a torsion type damper, further having a central veil;

[0070] - The damping system may be a pendulum type damper;

[0071] - The damping system may be a torque limiter type damper, further having a central web and retaining discs, preferably with friction linings;

[0072] - The double damping flywheel may comprise an internal volume delimited at least by the primary inertia mass, by a cover arranged axially between the inertia mass and the secondary inertia plate and by sealing means comprising at least one sealing membrane held by a connecting ring;

[0073] - The double damping flywheel may comprise first membranes sealing membrane and connecting ring mounted on the inertia mass side, and second sealing membrane and connecting ring mounted on the cover side. The first sealing membrane and connecting ring on the one hand, and the second sealing membrane and connecting ring on the other hand, may be at least partly axially opposite each other, in particular mounted on either side of the damping system;

[0074] - The first and second waterproofing membranes can be fixedly mounted on the damping system, for example on a central web or support of the damping system;

[0075] - The first connecting ring mounted on the inertia mass side, can be in bowl shape, to improve the sealing of the skeleton and the fixed support with the first waterproofing membrane.

[0076] The invention also proposes, according to a fourth aspect, a method of manufacturing a sealed cage of a flywheel called the aforementioned primary flywheel, which can take up all or part of the preceding characteristics, configured to introduce into a double damping flywheel a force, comprising at least the following steps:

[0077] a) Provide two plates and two sealing shells, with an X axis of revolution,

[0078] b) Opening and stamping a first plate to form a skeleton of an inertial mass;

[0079] Openwork and stamp a second plate to form a skeleton of a cover;

[0080] c) Fitting the inertial mass skeleton through the cover skeleton to constitute said cage, so as to delimit an internal volume;

[0081] d) Covering the inertial mass skeleton with a first sealing shell, in particular by fixing it to the inertial mass skeleton, and covering the cover skeleton with a second sealing shell, so as to seal the internal volume of said cage.

[0082] The advantage of this manufacturing method is to simplify the production of a sealed flywheel, with a hollowed-out, thinner, lighter body, to meet the functional needs of the inertia mass and the cover. This new form of internal structural skeleton makes it possible both to lighten the weight of each inertia part and to cope with its structural functions, i.e. the loads of the spring stop and the centrifugation constraints.

[0083] This reduces the need for material, CO2 emissions associated with manufacturing and operation on the vehicle. This results in a significant economic and ecological gain. This ensures a separation of the main functions of the primary flywheel: structural resistance (skeleton) vs. grease sealing (sealing shell).

[0084] Each inertia part can then be intended for a main function, which is specific to it.

[0085] According to this fourth aspect, the first and second sealing shells may be assembled together, in particular by folding the material of the sealing shells, made for example from their external periphery. The first and second sealing shells may be sealed together in a leaktight manner, preferably by double or triple stitching, or by electrode welding.

[0086] Any other assembly solution is also possible (welding, rivets, etc.).

[0087] In the remainder of the description and the claims, the following terms will be used without limitation: and in order to facilitate understanding, the terms "front" or "rear" according to the direction relative to an axial orientation determined by the main X axis of rotation of the transmission of the motor vehicle and the terms "inner / internal" or "outer / external" relative to the X axis and following a radial orientation, orthogonal to said axial orientation. Furthermore, certain elements can be indexed such as: the first and second skeletons, the first and second sealing shells, etc. This is a simple indexing to differentiate and name similar but not identical elements. Indexing does not imply a priority of one element over another and such names can easily be interchanged without departing from the scope of the description.

[0088] The invention will be better understood, and other aims, details, characteristics and advantages thereof will appear more clearly during the following description of a particular embodiment of the invention, given solely for illustrative and non-limiting purposes, with reference to the appended figures.

[0089] - [Fig.l] represents an exploded view of a double damping flywheel according to a first embodiment of the invention, comprising in particular a primary flywheel;

[0090] - [Fig.2] represents a radial sectional view of the so-called primary flywheel of the [Fig.l];

[0091] - [Fig.3] represents a detailed radial section of the so-called primary flywheel of [Fig.l];

[0092] - [Fig.4] represents a radial section of the double damping flywheel of [Fig.l];

[0093] - [Fig.5] represents another radial section of the double damping flywheel of the [Fig.l];

[0094] - [Fig.6] represents another radial section of the double damping flywheel of the [Fig.l];

[0095] - [Fig.7] represents a detailed radial section of the double damping flywheel of the [Fig.l];

[0096] - [Fig.8] represents a radial section of a double damping flywheel according to a second embodiment of the invention, comprising a pendulum-type damping system;

[0097] - [Fig.9] represents a radial section of a double damping flywheel according to a third embodiment of the invention, comprising a torque limiter type damping system.

[0098] - [Fig. 10] represents an example of assembly of the sealing shells of the [Fig.l];

[0099] - [Fig.l 1] represents another example of assembly of the sealing shells of [Fig.l];

[0100] - [Fig.11], [Fig.12], [Fig.13], [Fig.14], [Fig.15], [Fig.16], [Fig.17] and [Fig.18] illustrate the steps of the method of manufacturing the flywheel according to the first embodiment of the invention;

[0101] - [Fig.19] represents another example of assembly of the sealing shells of [Fig.l];

[0102] [Fig.l], [Fig.4] to [Fig.9] illustrate a torsion damper, in particular a double damping flywheel 1 of a powertrain comprising at least one internal combustion engine, a gearbox as well as for example a clutch arranged between the gearbox and the internal combustion engine. The double damping flywheel 1 is intended to be arranged between the internal combustion engine and the clutch of a mobility device, in particular a vehicle, in order to transmit a force generated by the internal combustion engine to the clutch, then to the gearbox. By "mobility device" is meant all motor vehicles, passenger, but also industrial, in particular heavy goods vehicles, public transport vehicles or agricultural vehicles, or any transport device allowing a living being and / or an object to move from one point to another. The latter may include a hybrid, electric and / or small mobility engine.

[0103] The clutch may be of the wet or dry type. A wet clutch is understood to mean a clutch adapted to operate in an oil bath. The clutch may be a double or a triple clutch.

[0104] In the case of a wet triple clutch architecture, the clutches can be concentric and arranged radially in the same plane. The axial size is then reduced.

[0105] As illustrated in exploded view in [Fig.l], the double damping flywheel 1 comprises at least

[0106] - a flywheel 2 also called primary flywheel, intended to be coupled to an engine crankshaft, and configured to introduce force into the double damped flywheel.

[0107] - a secondary flywheel 5, movable in rotation relative to the flywheel 2 around an axis of rotation X, coupled in rotation with a gearbox, for example to deliver force to a clutch;

[0108] - a bearing 51 to allow rotation between the primary flywheels 2 and secondary 5.

[0109] - a damping system 30, 30P, 30T which may comprise at least:

[0110] - a series of elastic members 33, here helical or curved springs intended to be arranged between the flywheels 2, 3 and configured to dampen the rotational acyclisms produced by the engine;

[0111] - an inertia member, for example a web 31, 31C or a central flange 31 R, intended to be fixed to a secondary inertia mass 50 provided with a hub 500, of the monobloc type.

[0112] The inertia member and the hub may be connected together, for example by riveting. The inertia member is configured to compress the elastic members during a relative rotation between the flywheels 2, 5.

[0113] The elastic members 33 are arranged in an internal volume V0 of the flywheel which may also comprise at least one retaining chute 32. The chutes 32 are formed from a longitudinally and transversely curved sheet metal. The internal volume VO contains a lubricating agent, preferably oil or grease. Thus the elastic members 33 are lubricated within the flywheel.

[0114] Furthermore, the flywheel 2 is formed:

[0115] - a primary hub 100 intended to be received on a driving shaft;

[0116] - of a main inertial mass 10 of multi-block shape, of radial extensions and axial, arranged on a front side AV of the damping system. It is configured to be connected to a driving shaft; and

[0117] - a cover 20 of multi-block shape, of radial extension, arranged on a rear side AR of the damping system. It is configured to be fixed on the inertia mass 10 and to cover or delimit at least partially the internal volume V0 of the flywheel 2.

[0118] The inertia mass 10, the cover 20 and the inertia plate 31 together delimit at least the internal volume V0 in which components of the damping system are contained.

[0119] In the first embodiment of the invention, the damping system is a torsion type damper, further comprising a central support called a sail 31 and a series of elastic members 33.

[0120] As an example in [Fig.8] of a second embodiment, similar to the first embodiment, it has been illustrated on the contrary that the damping system is a pendulum damper.

[0121] A pendulum damping device may comprise a connecting member called a spacer (not shown), coupling the at least one oscillating mass through a support window, for example by being riveted or force-fitted. The pendulum damping device is defined as a centrifugal device which comprises at least:

[0122] - a pendular support 31C mobile in rotation around the X axis, and in particular in which a support window can define a support rolling track;

[0123] - one or more pendulum bodies 31C composed of pendulum masses, mounted oscillating and arranged outside on either side of the pendulum support, in particular around an axis parallel to the X axis, and in which a pendulum body rolling track is provided;

[0124] As an example in [Fig.9] of a third embodiment, similar to the first embodiment, it has been illustrated on the contrary that the damping system is an internal torque limiter.

[0125] An internal torque limiter comprises a torque input member, here a movable central flange 31R, which receives elastic members 33, and a torque output member, composed of two retaining discs 32R connected to the secondary flywheel 5. The two retaining discs 32R are connected to each other, for example by riveting, in order to form a housing inside which the movable central flange 31R operates. Friction linings may be arranged on the central flange 31R and / or on at least one of the retaining discs 32R.

[0126] To prevent lubricant leaks from the internal volume V0, the double damping flywheel further comprises sealing membrane(s) 41 and connecting ring(s) 42, arranged on either side of the damping system.

[0127] In the illustrated examples, the first sealing membrane 41 and connecting ring 42 are mounted on the one hand, on the inertia mass side, and the second sealing membrane 41 and connecting ring 42 are mounted on the other hand, on the cover side. In addition, the connecting ring 42 on the cover side is cup-shaped. The latter are fixedly mounted on the damping system, for example on a web 31, on a pendulum support 31C or on the retaining discs 32R.

[0128] In all these embodiments, the primary flywheel 2 is cage-shaped. In other words, the inertial mass 10 consists of a skeleton 11 which comprises a series of perforated openings 15, which are sized to contain the damping system 30, 30P, 30T.

[0129] Similarly, the cover 20 consists of a skeleton 21 which comprises a series of perforated openings 25 sized to contain the damping system 30, 30P, 30T.

[0130] Such skeletons 11,21 delimit this internal volume V0.

[0131] The number of openwork openings 15, 25 per skeleton 11, 21 is for example greater than or equal to twenty.

[0132] The skeletons 11, 21 each comprise a central axial portion, from which openwork openings 15, 25 are made, for example in the form of windows 150 having a closed contour.

[0133] Such skeletons 11, 21 constitute a primary subassembly as illustrated in [Fig. 3] and [Fig. 15]. Furthermore, the series of openwork openings 15, 25 of each skeleton 11, 21 defines:

[0134] - wire bases 17, 27, forming the joints and attachments of the skeleton, from which the skeleton is mounted. These wire bases are subsequently called the force or anchor points 17, 27;

[0135] - material junctions 271, such as connecting arms or branches (main bending axes); and

[0136] - connecting portions 273 terminal between the latter (patterns, windows, cutouts of the wall), defining the geometric contours of the skeleton (half-stops, external and internal border);

[0137] These points of force or anchoring 17, 27 are at least distributed, according to a distribution regular or uniform: along the outer edge of the skeleton, and preferably on a central axial portion of the skeleton, which may be radially close to the primary hub 100.

[0138] Each series of perforated openings 15, 25 passes right through the respective thickness of the skeleton 11, 21, in order to lighten the latter. In particular, the series of perforated openings 15, 25 is provided over more than half of each skeleton 11, 21. As a result, each skeleton 11, 21 can be defined as a framework of material, of thin thickness and minimal weight to perform the inertia and housing function for the damping system. Hence a better associated acceleration for the flywheel.

[0139] Advantageously, the skeleton 21 is of thinner thickness than the skeleton 11. In addition, the skeletons 11, 21 are of different shapes, as detailed below.

[0140] By way of example, the windows 15 are angularly delimited from each other by connecting arms 171, distributed regularly around the X axis. Thus the outline of the windows 15 is in the form of a quadrilateral.

[0141] By way of example, the windows 25 of the cover are distributed under a series of patterns each comprising several spaced cutouts. In [Fig. 3], such a cutout pattern comprising a number of three spaced windows 25 is circled in dotted lines. The number of windows per pattern may be greater.

[0142] [Fig.3] and [Fig.15] illustrate in detail the patterns of the skeleton 21, here eight in number, spaced apart from each other. Each window 25 of the skeleton of the cover can be of substantially triangular shape.

[0143] Furthermore, each window pattern is in itself symmetrical, having an axis of symmetry SL. Thus the three windows 25 of the same pattern are arranged in a symmetrical manner, along the axis of symmetry SL. Each symmetrical pattern can comprise at least: a central window, here distal, that is to say distant from the axis X, and two lateral windows, here proximal, that is to say close to the axis X.

[0144] Within a cut-out pattern, the windows 25 are delimited by branches 272, connected to each other by a force point 17, 27. The skeleton 11 may comprise an alternation of force points and anchor points. For example, a window pattern 25 may be in the form of a petal. Furthermore, the cutting patterns are distributed regularly around the X axis, according to a uniform distribution. As a result, two cutting patterns may be brought together, and be arranged in a symmetrical manner, along an axis of symmetry S2. These two patterns form a group of symmetrical patterns along the axis of symmetry S2. In a variant not shown, at least three patterns may constitute a group of patterns.

[0145] Furthermore, at least some cut patterns are delimited by connecting arms 271. Thus the connecting arms delimit the groups of cut patterns. Each axis of symmetry SI or S2 passes through a force or anchor point 17, 27. The axes of symmetry SI and S2 are perpendicular to the X axis.

[0146] In a variant not shown, the outline of the windows may be circular or oblong in shape.

[0147] By way of example, the skeleton 11 of the inertial mass is provided with force or anchoring points 17, 27 between which at least certain perforated openings 15 are made. The perforated openings 15 are separated alternately by arms 271. Each arm 271 can be connected between two radially opposite force or anchoring points 17.

[0148] In another example, the skeleton 21 of the cover is provided with force or anchoring points 17, 27 around which at least certain openwork openings 25 are made. In this situation, the openwork openings are separated alternately by branches 271 of material. The branches 271 of the same pattern can be connected between at least three radially and / or circumferentially opposite force or anchoring points 17.

[0149] As illustrated in [Fig.l] to [Fig.3], the skeletons 11, 21 of inertia mass 10 and of the cover 20 may respectively comprise a first and a second half-stops 1710, 2710 intended to cooperate to form a stop of an elastic member 33. The elastic members 33, here two in number, are compressed between the stop formed by the inertia mass 10 and the cover 20 on the one hand and a fin of the central support 31 on the other hand during a relative rotation between the flywheels 2, 5.

[0150] By way of example, the skeleton 11 of the inertial mass comprises on its external periphery, a radial wall, from which are made openwork openings 15, 25 in the form of notches. That is to say having an open type contour, preferably made from a radial portion of said skeleton.

[0151] As a result, the radial wall is angularly discontinuous around the axis X. This radial wall serves both as a retainer for the damping system and as a discontinuous assembly connection 170 with the skeleton 21 of the cover. For example, this discontinuous radial wall extends from a peripheral annular rim 110 of the skeleton 11, beyond which the notched openwork openings 15 extend.

[0152] Furthermore, the skeletons 11, 21 are assembled by cooperation of shapes in one another.

[0153] In the illustrated examples, the assembly connection 17 is a fitted connection 170 of the skeleton 11 and in particular of the discontinuous radial wall of the primary mass, in a skeleton 21 of the cover.

[0154] As illustrated for example in [Fig.3], the skeleton 21 comprises a peripheral axial portion, for example stamped, from which openings are made. openwork 15, 25 in the form of lights. Thus the discontinuous radial wall of the skeleton 11 crosses the lights of the skeleton 21.

[0155] In the first embodiment, the fitted connection 170 of the skeletons 11, 12 is made by means of stop pins, in particular made from the material of the skeleton 11. The spaced portions of the discontinuous radial wall of the skeleton 11 therefore form stop pins 175. [Fig.4] and [Fig.5] illustrate stop pins 175 to be fitted, of flat shapes, preferably stamped. The slots of the skeleton 21 are of shapes complementary to those of the stop pins 175 of the skeleton 11. In the examples illustrated, the stop pins 175 to be fitted are provided at their end with retaining pins 177 configured to deform after their passage through the slots of the skeleton 21, to complete the fixing of the skeletons. In a variant not illustrated, it is possible to weld the fitted connection of the skeletons, by adding a weld with or without adding material.

[0156] To partially contain a lubricant of the internal volume V0, the inertial mass 10 further comprises a sealing shell 13 covering the skeleton 11 and in particular the perforated openings 15.

[0157] [Fig.2], [Fig.17] and [Fig.18] illustrate a subassembly of the primary flywheel composed of skeletons 11, 21 and sealing shells 13, 23, connected to each other.

[0158] - The shell 13 called the first shell, is of a thinner thickness than that of the skeleton 11. The cover 20 further comprises a sealing shell 23 covering the skeleton 21 and in particular the perforated openings 25.

[0159] - The shell 23 called the second shell is of a thinner thickness than that of the skeleton 21.

[0160] - The sealing shells 13, 23 may be of equal thickness.

[0161] - The sealing shells 13, 23 can be molded or overmolded, in particular in plastic.

[0162] Advantageously, each sealing shell 13, 23 is fixedly mounted to the skeleton which it covers, for example to the hub of certain perforated openings of the skeleton designed for this purpose, called mounting orifices 250.

[0163] Each sealing shell 13, 23 can be mounted pressed against the skeleton 11, 21 which it covers. Their shape can be produced by deformation of material, and comprise at least portions of shapes complementary 113, 213 to those of the skeleton 11, 21 which they cover.

[0164] - For example, one of the sealing shells may be made of metal. The other The sealing shell can be made of plastic or made by overmolding material, for example based on the shape of the shell or the skeleton it covers. This also limits grease leaks;

[0165] - For example, the sealing shells may be made of plastic. In a In such a situation, it is possible to assemble the sealing shells by ultrasonic welding;

[0166] Each sealing shell 13, 23 may be of a shape similar to that of the skeleton 11, 21, such a shell shape being called an imprint shape 111, 211. Thus the mounting holes 250 receive fixing means for the sealing shells 13, 23, whether or not made from the material of a shell, such as rivets, spacers, extruded pins 180, or even deformed conical portions 215.

[0167] - As an example, the sealing shell 13 is fixed through orifices of mounting 250 of the skeleton 11 by extruded pins 180. [Fig.6] to [Fig.7] illustrate the extrusion of material 185 of a pin 180.

[0168] - By way of example, the sealing shell 23 comprises an internal collar.

[0169] - By way of example, the sealing shell 23 comprises deformed portions called caps 215 of material resulting from the deformation of material of the shell 23, and they also allow the sealing shell to be fixed to the skeleton 21. The caps 215 can be produced directly from these mounting holes 250 of the skeleton. [Fig.6] illustrates these caps 215 of tubular shapes, housed through the mounting holes 250.

[0170] In the examples illustrated, the double damping flywheel 1 further comprises a target 91 intended to be arranged opposite a sensor capable of delivering a signal representative of the angular position and / or the speed of the target. This target 91 is here in the form of an annular crown provided with teeth 92.

[0171] The target 91 can be mounted to bear on the sealing shell 13 of the inertia mass.

[0172] The sealing shells 13, 23 can be assembled together in a sealed manner, by a locking connection 900 sealing the shells 13, 23, for example produced by folds of material of the shells.

[0173] [Fig.4] to [Fig.6] and [Fig.8] illustrate a double type locking link 900

[0174] [Fig. 10] illustrates a so-called triple-seam locking connection, formed of three folds of shell material.

[0175] [Fig. 11] illustrates another locking connection called double seam, formed by two folds of material of the shells. Such a double crimping ("double seam" in English) or triple crimping 900 of the shells 13, 23, creates a hermetic seal 903 by fitting the edges (or rims) of both the shell 23 of the cover (peripheral end) and the shell 13 of the inertia mass.

[0176] [Fig. 19] on the contrary illustrates another locking connection 900 for which the shells 13, 23 are axially joined to each other, by their radial contact face 1300, 2300. An electrode weld (seam weld in English) is then possible: The two shells to be welded are kept under pressure and placed between two roller electrodes (called upper and lower electrode wheel in English) to be connected according to [Fig. 19].

[0177] We will now describe the method of manufacturing a sealed cage of the flywheel 2.

[0178] Firstly (step a) two plates of revolution axis X are provided, and in addition two sealing shells, configured to contain a lubricating agent. It is also possible to provide: - a damping system comprising at least one inertia member 31, 31C, 31R, two elastic members 33 and two retaining channels 32; - sealing membrane(s) 41 and connecting ring(s) 42, etc.;

[0179] The first and second plates are then cut out and stamped (step b):

[0180] - to form a skeleton 11 of an inertial mass 10, as illustrated in [Fig. 12], in in particular producing a discontinuous radial wall which can be formed from stop pins 175 to be fitted;

[0181] - to form a skeleton 21 of a cover 20, in particular by producing or openwork openings 15 for fitting the discontinuous radial wall and in particular the stop pins 175;

[0182] The chutes 32 and the elastic members 33 are then mounted, as illustrated in [Fig. 13], inside the skeleton 11, arranging them to bear against the radial wall and in particular against the stop pins.

[0183] The other components of the damping system are then mounted, as illustrated in [Fig. 14], inside the skeleton 11, which may include sealing membrane(s) 41 and connecting ring(s) 42 previously fixed to the damping system.

[0184] The inertial mass skeleton 11 is then fitted (step c), as illustrated in [Fig. 15], through the cover skeleton 21 to form the cage, so as to delimit an internal volume V0.

[0185] The cover skeleton 21 is then covered (step d), as illustrated in [Fig. 16], with a sealing shell 23, preferably by fixing it to the skeleton 21, to seal the skeleton 21.

[0186] As illustrated in [Fig.17], the inertial mass skeleton 11 is also covered with a sealing shell 13, preferably by fixing it to the skeleton 11, to seal the skeleton 11.

[0187] The first and second sealing shells 13, 23 are then assembled together. Preferably, by double or triple crimping, as described below:

[0188] - During a first step, we carry out:

[0189] - by a fold of material, at the end of the shell 13 of the inertial mass, a 901 hook-shaped bridle body, which is rolled down (when double sewing);

[0190] - by a fold of material, at the end of the shell 23 of the cover, a cover hook-shaped, i.e. an edge 902 which is curved inwards after the formation of the flange body;

[0191] - During a second step, we carry out:

[0192] - by another fold of material, at the end of the shell 13 of the inertial mass, a winding profile 904 for example C-shaped, before pushing it into the cover of the lid hook. Which partially winds it, under the edge of the shell 13;

[0193] - a crimping mandrel is then used in conjunction with rollers of crimping, and acts both as a clamp to hold the shell 23 in place during crimping and as an anvil to support the shell 23 of the cover as a crimping roller pushes against it to form the metal.

[0194] During this step, the folded materials which are compressed and flattened against the side of the flange body 901, create a lubricant-tight seal 903 as illustrated in [Fig.11].

[0195] To form a triple crimping, it is sufficient to produce another profile 905 for winding the shell 23 of the cover. This also creates another watertight seal 903 as illustrated in [Fig.10]. As illustrated in [Fig.15], a target 91, 92 is fixedly attached to the shell 13 of the inertia mass, from a recess 139 in the shell 13. This shell recess 139 is here of a shape complementary to that of the target, here of truncated cone shapes. The shell 13 may comprise a boss of material, on the periphery of the target, to center the latter.

[0196] The invention cannot, however, be limited to the means and configurations described and illustrated here, and it also extends to any equivalent means or configuration and to any technical combination operating such means.

[0197] In particular, the shape of the skeletons and the sealing shells can be modified without harming the invention, insofar as these components, ultimately, fulfill the same functions as those described in this document. In the claims, any reference sign in parentheses cannot be interpreted as a limitation of the claim.

Claims

Claims

1. Flywheel (2) in the form of a cage, in particular for a double damping flywheel, configured to contain a damping system (30, 30P, 30T, 31, 32, 33) and to introduce a force into the damping system, produced by assembling an inertial mass (10) and a cover (20) with an axis (X) of revolution, the inertial mass (10) or the cover (20) being intended to partially contain the damping system (30, 30P, 30T, 31, 32, 33) inside an internal volume (V0) delimited in part by at least one skeleton (11, 21), extending on one side of the damping system and which comprises a series of perforated openings (15, 25) of dimensions adapted to contain said system damping, the assembly of the inertia mass (10) and the cover (20) being carried out in particular by an assembly connection (17) fitted from a first skeleton (11) of the primary mass (10) into a second skeleton (21) of the cover (20),for example an assembly connection exempt from welding, the first skeleton (11) of the inertia mass (10) being covered by a first sealing shell (13), and the second skeleton (21) of the cover (20) being covered by a second sealing shell (23), so as to partially contain a lubricant of the damping system within said internal volume (V0), the fitted connection (170) being covered by the second sealing shell (23).,

2. Flywheel (2) according to claim 1, wherein - the series of openwork openings (15, 25) is provided over at least 40% of a total area of ​​the part forming said skeleton, the series of openwork openings (15, 25) being preferably formed in the form of windows (150) or symmetrical patterns, in a regular or uniform distribution, and / or - the first and / or second skeletons are provided with force or anchoring points (17, 27) distributed at least along the outer edge of the skeleton, around which or between which the openwork openings (15, 25) are distributed,

3. Flywheel (2) according to the preceding claim, in which - the material of the first and / or second sealing shells (13, 23) is chosen from the following list: stainless steel, plastic or polymer materials, aluminum, materials produced by overmolding; and / or - the first and second sealing shells (13, 23) are fixedly mounted to the skeleton which they cover, - by plating the shell in the form of an imprint (111, 211) with said skeleton, and / or - by cooperation of deformed shapes (215) of the shell with openwork openings, and / or - by mounting orifices (250) formed among the series of openwork openings of the skeleton, from which rivets, spacers (18) or extruded pins (180) connecting said shell are passed through.

4. Flywheel (2) according to any one of the preceding claims, in which the first and second sealing shells (13, 23) are sealed together: - by overmolding material from one end of one shell onto the end of the other shell; or - by crimping or double crimping the shells, preferably hot; or - by folding material from the ends of the shells; or - by embracing the ends of the shells and / or by continuous or discontinuous welding of the shells, for example by electrode welding.

5. Flywheel (2) according to any one of the preceding claims, in which the fitted connection (170) is formed by means of flat, stamped stop pins (175), made from the material of the first skeleton (11) and passing through the second skeleton (21), the stop pins to be fitted preferably being provided at their end with deformable retaining pins (177).

6. Flywheel (2) according to any one of the preceding claims, in which it further comprises a target (91, 92) in the form of an annular crown mounted to bear on the first sealing shell (13), intended to be arranged opposite a sensor capable of delivering a signal representative of the angular position and / or the speed of the target, the target being in particular housed from a recess (139) of the first shell (13), of complementary shapes, for example frustoconical.

7. Double damping flywheel (1) for a mobility device, comprising a flywheel (2) called primary according to any one of the preceding claims, configured to introduce into the double flywheel shock absorber a force, at least one inertia plate (31) called secondary, configured to deliver the force to a clutch, the flywheel (2) and the flywheel plate (50) delimiting at least said internal volume (V0) in which are contained: a lubricant and at least in part a damping system (30, 30P, 30T) arranged on a force transmission path between the primary flywheel and the secondary flywheel plate, the damping system being a torsion type (30) or pendulum type (30P) or torque limiter type (30T) damper and / or being provided with at least one series of elastic members (33).

8. Method of manufacturing a sealed cage of a primary flywheel (2), configured to introduce a force into a double damping flywheel, comprising at least the following steps: a) Provide two plates and two sealing shells, with an axis (X) of revolution, b) Opening and stamping a first plate to form a skeleton (11) of an inertial mass (10); Openwork and stamp a second plate to form a skeleton (21) of a cover (20); c) Fit the inertial mass skeleton (11) through the cover skeleton (21) to form said cage, so as to delimit an internal volume (V0); d) Covering the inertial mass skeleton (11) with a first shell (13) by fixing it to the inertial mass skeleton (11), and covering the cover skeleton (21) with a second sealing shell (23), so as to seal the internal volume (V0) of said cage, the first and second sealing shells (13, 23) being in particular assembled together.

9. A manufacturing method according to claim 8, wherein the first and second sealing shells (13, 23) are sealed (900) together in a watertight manner, preferably by double stitching or triple stitching, or by electrode welding.

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