FR2870902A1 - Antifriction bearing for flywheel, has bearing units disposed between two rings, and friction organ disposed in bearing units that are seamless steel shells and including ring gear provided of radial corrugations - Google Patents

Abstract

The bearing has bearing units (8) disposed between two rings (4, 5), and a friction organ (10) disposed in the bearing units, where the bearing units are seamless steel shells. The friction organ comprises of a ring gear provided of radial corrugations whose apex elastically rests against the rings. The friction organ is disposed between a radial surface of one ring and a radial surface of a fixing unit of another ring. An independent claim is also included for a flywheel comprising an antifriction bearing.

Description

Inertia flywheel rolling device

  The present invention relates to the field of flywheels with two masses, generally provided with dampers torsional oscillations.

  These two-mass flywheels are mounted between the crankshaft of an internal combustion engine and the gearbox in order to decouple the gearbox from vibrations and torsional oscillations due in particular to the acyclisms of the engine. The steering wheel comprises two disks or plates mounted one beside the other and concentrically by means of a bearing. The primary and secondary plates are angularly connected by torsion damping springs. The set of plates rotate in rotation about a common axis, the secondary plate being able to move angularly in a certain limited angular range with respect to the primary plate during the damping of the oscillations.

  Such a device is known from document FR-A-2 754 034. However, this mechanism comprises a large number of parts including many machined parts particularly expensive and occupies a large space.

  The present invention aims to remedy these disadvantages.

  The present invention provides a dual-mass flywheel and a low mass flywheel bearing, compact, comprising a small number of parts to assemble, simple assembly and economical manufacturing.

  The flywheel bearing device, according to one aspect of the invention, comprises a row of rolling elements arranged between two rings, and a friction generating system disposed in the bearing, the bearing rings being made of pressed sheet metal. .

  The use of pressed sheet metal rolling bearings, of substantially constant thickness, makes it possible to achieve substantial gains in mass and a reduction in manufacturing costs. Indeed, simple stamped rings that have undergone heat treatment are sufficient for this type of application, whereas a conventional roller bearing 2870902 2 massive deep grooves must undergo turning operations, heat treatment and grinding. The integration into the bearing of the friction generating system saves space compared to the conventional system, reduces the number of parts assembled at the equipment manufacturer and simplifies the internal structure of the flywheel.

  In one embodiment of the invention, one of the rings axially exceeds the other ring on one side of the bearing, while on the other side, the other ring axially exceeds the first ring.

  This facilitates the fixing of each ring on a corresponding flywheel plate.

  In one embodiment of the invention, the friction generating system is disposed radially between the two rings of the bearing. The friction generating system can be attached to one of the rings and in frictional contact with the other ring.

  In one embodiment of the invention, the friction generating system comprises a ring provided with radial corrugations whose vertices resiliently bear on bearing surfaces of the inner ring and the outer ring.

  In one embodiment of the invention, the friction generating system is disposed axially between a radial surface of one of the rings and a radial surface of an element fixed on the other ring.

  In one embodiment of the invention, the friction generating system comprises an axially elastic washer.

  In another embodiment of the invention, the friction generating system comprises an axial corrugated washer.

  In another embodiment of the invention, the friction generating system comprises a frustoconical elastic washer.

  In one embodiment of the invention, the device comprises a lock washer fixed on the other ring. The lock washer may be in contact with the friction member.

  2870902 3 The integration of the friction generating system in the bearing reduces the number of parts to be assembled at the equipment manufacturer who manufactures the flywheel.

  The invention also proposes a flywheel comprising a primary plate, a secondary plate and a rolling bearing provided with a row of rolling elements arranged between two rings. The rolling bearing further comprises a friction generator system disposed between the rings of said bearing, the rings of said bearing being of pressed sheet metal.

  The invention will be better understood on reading the detailed description of some embodiments taken as non-limiting examples and illustrated by the appended drawings, in which: FIG. 1 is a partial view in axial section of a flywheel according to one aspect of the invention; FIG 2 is a radial sectional view along II-II of Figure 1 of a bearing according to one aspect of the invention; FIGS. 3 and 4 are views in axial section of a flywheel according to other embodiments of the invention.

  As can be seen in FIG. 1, the flywheel comprises a primary plate 1, in the form of a radial circular metal part, a metal secondary plate 2, of similar shape, and a rolling bearing 3 disposed between the primary plate 1 and the secondary plate 2.

  The rolling bearing 3 is of the angular contact type and comprises an outer ring 4, an inner ring 5, provided respectively with inner and outer races 6 and 7, a row of rolling elements 8, here balls, arranged between the raceways 6 and 7, a cage 9 for maintaining the circumferential spacing of the rolling elements 8 made for example of synthetic material, a friction member 10, a seal 12 disposed at the axial end of one of the rings and a labyrinth seal 13 disposed at the end opposite the seal 12.

  One could of course provide a bearing with no cage and in which the balls 8 would be joined.

  More specifically, the outer ring 4 made of pressed steel sheet comprises an axial portion 4a forming the free end of the outer ring 4 on the side of the primary plate 1 and in the bore of which is fixed the seal 12 shown so schematically, a substantially toroidal portion 4b on the inner surface of which is formed the raceway 6, an axial portion 4c having a diameter smaller than that of the axial portion 4a and whose bore is in contact with the friction member 10, an oblique flange 4d directed inwards, an axial portion 4th of smaller diameter than that of the axial portion 4c and a radial flange 4f directed inwards and having an axial free end forming the labyrinth seal 13 with the ring 5. The flange 4f is fixed by welding to a radial surface of the plate 2, for example by a weld bead 14.

  In other words, the outer ring 4 is monobloc and has three axial portions of stepped diameters, the largest supporting the seal 12 and being tangential to the raceway 6 and the one having an intermediate diameter being in contact with the friction 10.

  The inner ring 5 made of stamped steel sheet comprises a large diameter axial portion 5a fixed to an axial surface of the primary plate 1 by welding, for example by the weld bead 15, a radial portion 5b directed inwards to from the end of the axial portion 5a opposite the primary plate 1, a short axial portion 5c extending the radial portion 5b at its small diameter end, and directed towards the secondary plate 2, the seal 12 rubbing on the outer surface of the axial portion 5c, a toroidal portion 5d extending the axial portion 5c towards the secondary plate 2, and whose outer surface forms the raceway 7, an axial portion 5f extending the small diameter end of the toroidal portion 5d in the direction of the secondary plate 2, another axial portion 5g, of slightly reduced diameter compared to that of the axial portion 5f and don the outer surface is in contact with the friction member 10.

  The axial portion 5g terminates in a radial surface 5h. The outer surface of the axial portion 5g, close to the radial surface 5h, also forms the labyrinth seal 13 with the end of the flange 4f of the outer ring 4. The rolling track 6 is arranged with respect to a radial plane passing through the center of the rolling elements 8, on the side of the secondary plate 2. On the contrary, the raceway 7 is arranged with respect to the same radial plane passing through the center of the rolling elements 8, on the side of the primary plate 1.

  Alternatively, it may be provided to extend the axial portion 4a of the outer ring 4 towards the radial portion 5b of the inner ring 5 to form a narrow passage from, either in addition to the seal 12, or replacing. Another seal may also be disposed in the space remaining axially between the friction member 10 and the radial flange 4f of the outer ring 4, and radially between the axial portion 4e of the outer ring 4 and the axial portion. 5g of the inner ring 5. It is also possible to provide a cage 9, sealing between the rolling elements 8 and the friction member 10, by forming narrow passage, or by means of friction lips.

  As seen more particularly in Figure 2, the friction member 10 is in the form of a radially corrugated element, said member 10 being prestressed radially between the outer ring 4 and the inner ring 5 of the bearing. The friction member may be a washer or an open ring. The corrugations alternately come into contact with the bore of the axial portion 4c of the outer ring 4 and the cylindrical outer surface of the axial portion 5g of the inner ring 5. Such a friction member is particularly economical and durable. It can be mounted simply by fitting it into the outer ring before mounting the rolling elements 8.

  In the embodiment illustrated in FIG. 3, the friction member is in the form of a ring of rectangular section made of synthetic material placed between the bore of the axial portion 4c and the outer surface of the axial portion 5g. , the friction member 2870902 6 being radially prestressed between the outer ring 4 and the inner ring 5 of the bearing.

  In the embodiment illustrated in FIG. 4, the outer ring 4 comprises, going from the plate 1 towards the plate 2, an axial portion 4a, a toroidal portion 4b whose inner surface forms the rolling track 6, a short portion substantially axial 4c, an inwardly directed radial portion 4g, an outwardly directed radial portion 4h and an axial portion 4i, of a diameter slightly greater than that of the axial portion 4a, and directed away from it. The radial portions 4g and 4h are close to one another and come close to the inner ring 5 to form a narrow passage 13.

  The inner ring 5 is close to that illustrated in FIG.

  The friction member 10 is here in the form of an elastic washer axially corrugated, in frictional contact on the surface of the radial flange 4h on the opposite side to the rolling elements 8.

  The rolling bearing 3 further comprises an annular lock washer 16 comprising a radial portion 16a terminating inwardly by an oblique portion 16b divided into a plurality of tongues and forcibly mounted on the outer surface of the the axial portion 5e of the inner ring 5 and is now by buttressing. In other words, the lock washer has a washer shape whose inner edge is folded in an axial direction relative to the radial portion 16a, the folding being carried out in a direction opposite to the axial direction of the assembly. The oblique portion 16b thus allows a firm axial locking of the lock washer on the inner ring 5. The friction member 10 is held axially pinched between the radial flange 4h of the outer ring 4 and the radial portion 16a of the lock washer 16 In addition, the bearing 3 is thus placed under a slight axial prestress, which facilitates its handling and transport and can be favorable to its proper operation. The narrow passage 13 formed between the outer 4 and inner 5 rings is located between the rolling elements 8 and the friction member 10, which avoids the intrusion, near the rolling elements 8, of any metal particles due to friction. the friction member 10 on the outer ring 4 or the lock washer 16.

  The axial portion 4i of the outer ring 4 protrudes beyond the free end of the axial portion 5f of the inner ring 5 and can thus be fixed, for example by welding, on the secondary plate 2. The axial portion 5a the inner ring 5 protrudes axially beyond the free end of the axial portion 4a of the outer ring 4 and can thus be fixed, for example by welding, on the primary plate 1.

  It is therefore understood that it is particularly advantageous that one of the rings protrudes axially from one side to the other, and that the other ring protrudes from the opposite side with respect to the first.

  In addition, it is easily possible to provide rubbing seals, even having a high friction, to the extent that such friction can participate in damping oscillations and vibrations.

  By way of example, provision could be made in the embodiment of FIG. 5 to add a seal between the axial portions 4i and 5f of the outer and inner rings 4 and 5, respectively, in order to avoid intrusion of foreign elements near the lock washer 16 and the friction member 10.

  The invention thus makes it possible to produce a flywheel with a simple structure and a reasonable manufacturing cost, in fact the rolling rings made of pressed sheet metal are more economical than the machined rings provided with deep grooves.

  In addition, the bearing incorporates the torsional damping system, which significantly reduces the number of parts to be assembled at the flywheel manufacturer and provides significant gains in terms of assembly time and overall size. of the device.

Claims (10)

  1-rolling bearing device (3) of flywheel, comprising a row of rolling elements (8) arranged between two rings (4, 5), characterized in that it further comprises a generator system of friction (10) disposed in said bearing, the rings of said bearing being of pressed sheet metal.   2-Device according to claim 1, characterized in that one of the rings axially exceeds the other ring on one side of the bearing, while on the other side, the other ring axially exceeds the first ring .   3-Device according to claim 1 or 2, characterized in that the friction generating system (10) is disposed radially between the two rings of the bearing.   4-Device according to any one of the preceding claims, characterized in that the friction generating system (10) comprises a ring provided with radial corrugations whose vertices resiliently bear against the bearing surfaces of the inner ring and the outer ring.   5-Device according to any one of the preceding claims, characterized in that the friction generator system (10) is disposed axially between a radial surface of one of the rings and a radial surface of an element fixed on the other ring.   6-Device according to any one of the preceding claims, characterized in that the friction generator system (10) comprises an axially elastic washer.   7-Device according to any one of claims 1 to 5, characterized in that the friction generating system (10) comprises an axially corrugated washer.   8-Device according to any one of claims 1 to 5, characterized in that the friction generating system (10) comprises a frustoconical elastic washer.   9-Device according to any one of the preceding claims, characterized in that it comprises a lock washer (16) fixed on the other ring.   10-flywheel comprising a primary plate (1), a secondary plate (2) and a rolling bearing (3) provided with a row of rolling elements (8) arranged between two rings, characterized in that the rolling bearing further comprises a friction generating system (10) disposed between the rings of said bearing, the rings of said bearing being of pressed sheet metal.