JP2006515048A - Torque transmission flexible flywheel - Google Patents

Abstract

The present invention includes a radially inner annular element (26) secured to the input shaft and having means connected to the annular mass member (30) through at least two diametrically opposed radial arms (28). A torque transmitting device, in particular a motor vehicle flexible flywheel, wherein the radial arm (28) defines a flywheel vibration axis (34) having a predetermined angular position relative to the input axis, perpendicular to the axis of rotation. About.

Description

  The present invention relates to a torque transmission device, and more particularly to a flexible flywheel of an automobile. The flexible flywheel includes an annular mass member configured to be rotationally driven about a shaft by a drive shaft and supported by a flexible element configured to be fixed to the drive shaft. Yes.

  In the case of an automobile torque transmission device, the drive shaft is a crankshaft of an internal combustion engine, and the torque is usually transmitted to a drive element such as an input shaft of a gear transmission via at least one clutch and a vibration damper. Is done.

  In one example, the flywheel is the primary flywheel of a double flywheel damper. The double flywheel further comprises a secondary flywheel centered on the primary flywheel and rotatably guided via bearings, and a damping damper usually mounted between the two flywheels. The secondary flywheel forms a reaction plate for the clutch for transmitting torque to the input shaft of the transmission.

  In the current state of the art, the annular mass member of the flexible flywheel is usually formed by a cast iron ring gear fixed to the radially outer periphery of the flexible annular metal plate with screws or rivets. The radially inner periphery of the metal plate has a hole through which a screw for fixing the metal plate passes through the drive shaft, that is, in the case of a torque transmission device for an automobile, the crankshaft of the internal combustion engine.

  The flexible annular metal plate is relatively thin (e.g., about 2 to 3 mm), and the radial inner periphery for fixing the metal plate to the drive shaft has a thicker reinforcing washer against which the fixing screw head abuts. It is reinforced by. This thin annular metal plate must be inspected after cutting, strain removed as necessary, and carefully assembled to form an annular mass member of cast iron. These operations are quite time consuming and meticulous and expensive.

  In operation, this type of flywheel has a “pumping” bending deformation (a bending deformation in which the flexible flywheel remains substantially parallel to itself) or perpendicular to the axis of rotation of the flywheel, It undergoes deformation due to vibration about an axis having a defined angular position with respect to the crankshaft. This vibration is related to the bending of the last crankpin of the crankshaft. Known flexible flywheels are characterized by a rotationally symmetric structure and are not configured to take advantage of this vibration phenomenon.

  The object of the present invention is to obtain a flexible flywheel that satisfies the above requirements and is free from the disadvantages of prior art flexible flywheels.

  To this end, the present invention comprises an annular mass member configured to be driven about a rotational axis by a drive shaft and supported by a flexible element configured to be fixed to the drive shaft. A transmission device, in particular a flexible flywheel of a motor vehicle, wherein the flexible element comprises a radial arm defining a vibration axis perpendicular to the rotational axis of the flywheel. To do.

  The flexible flywheel according to the present invention is particularly adapted to absorb the vibration phenomenon at least partially by separating the flywheel that vibrates around the advantageous axis from the drive shaft in response to the vibration phenomenon described above. It is configured.

  In practice, it is advantageous if the radial arm of the flexible element is formed by an increase in the local thickness of the flexible element. That is, the flexible element is thick at the part forming the radial arm and thin at the other part. If the radial arm has sufficient thickness and rigidity to ensure torque transmission between the drive shafts, this thin portion can be reduced and can be omitted.

  The flexible element of the flexible flywheel according to the present invention can be formed of a metal plate thicker than the prior art in which the material of the metal plate is inferior, no pretreatment is required, and the operation can be easily performed. The flywheel according to the present invention is less expensive than the conventional one because it is less deformed and does not require strain relief.

  In addition, the flexible element and the annular mass member can be manufactured integrally with the annular mass member. In particular, the flexible element and the annular mass member can be formed from cast iron made of a material that can withstand bending stress and torsional stress. All problems and disadvantages associated with separately manufacturing and assembling the member and flexible element are eliminated.

  According to another characteristic of the invention, the vibration axis is essentially formed by two radial arms extending continuously from one another between the rotation axis and the annular mass member, or the vibration axis is Formed by three radial arms, the two radial arms being symmetrical to each other with respect to the extension of the third radial arm, each of these three radial arms having a rotational axis and an annular mass It extends between the members.

  In the first embodiment, the flexible element is formed by a disc including symmetrical cutouts formed on both sides of the vibration axis.

  This cutout may or may not penetrate.

  If the flexible element is not integrally formed with the annular mass member, the flexible element is secured to the annular mass member at the end of the radial arm with screws, rivets or the like.

  The flexible element may be formed as a single element made from a metal plate of the desired thickness, or may be formed as a plurality of flat elements that are superimposed and secured together to an annular mass member. Good.

  According to another feature of the invention, the flexible flywheel comprises hysteresis means supported by the flexible element and cooperating with the annular mass member by friction.

  In one embodiment, the hysteresis means extends perpendicular to the vibration axis and has two radii having a radially inner end integral with the flexible element and a radially outer end contacting the annular mass member. It has a direction arm.

  The radial arm of the hysteresis means is formed integrally with the flexible element or, as a variant, is formed as part of a washer attached to the flexible element, the washer comprising the flexible element At the same time, it is configured to be fixed to the drive shaft.

  In another embodiment, the hysteresis means comprises two tabs integral with the flexible element and a spring pin mounted in a semi-cylindrical housing of the two tabs integral with the annular mass member. The tab extends in a direction perpendicular to the vibration axis.

  According to yet another feature of the invention, the radial arm defining the vibration axis has a cutout or notch for positioning maximum stress between the radially inner end and the radially outer end. is doing.

  This allows maximum stress to escape from the region where the radial arm is fixed or connected to the annular mass member.

  The radial arm may extend perpendicular to the rotation axis, or may be inclined slightly from the inner end in the radial direction, for example, in a direction opposite to the drive axis, with respect to a perpendicular to the rotation axis.

  According to yet another feature of the invention, the flexible element comprises means for defining a rotation axis and a second vibration axis perpendicular to the first vibration axis.

  The two vibration axes are defined by the radial arms of the flexible element.

  In one embodiment of the present invention, the radial arm depends on whether the radial arm defining the first vibration axis or the radial arm defining the second vibration axis is connected to the annular mass member. The lug having different rigidity is connected to the annular mass member.

  The flexible flywheel according to the invention forms in particular the primary flywheel of a double flywheel damper. The double flywheel damper further includes a secondary flywheel configured to be connected to the input shaft of the transmission by a clutch, and a vibration damping damper attached between the two flywheels.

  In one embodiment of the invention, the damping damper is of the type including a spring oriented radially with respect to the axis of rotation at the position of the remaining part of the double flywheel damper.

  Hysteresis means associated with the flexible primary flywheel includes a spring washer, which is supported by the primary flywheel's flexible element and abuts the primary flywheel or allows for the primary flywheel. It is preferably mounted between the flexible element and an annular mass member supported by the flexible element.

  The invention will be better understood and other features, details and advantages of the invention will become apparent upon reading the following description, given by way of example, with reference to the accompanying drawings, in which:

  Reference is first made to FIGS. 1 and 2 which schematically show a first embodiment of a flexible flywheel according to the invention.

  This flexible flywheel, indicated as a whole by the reference numeral 10, is a drive shaft 12 that is a crankshaft of an internal combustion engine of an automobile, and an input shaft of, for example, a gear transmission, and is controlled coaxially with the flywheel 10 and the drive shaft 12. Torque is transmitted to and from a drive shaft (not shown) that is configured to be rotatably fixed to the hub 14 of the vibration damper.

  The hub 14 of the damping damper is connected to the flywheel 10 by a clutch E in a known manner and faces away from the drive shaft 12. The radial surface 16 of the flywheel 10 is connected to the friction disk 18 of the clutch E. It forms a friction surface that cooperates.

  The flywheel 10 according to the invention is fixed to the end of the drive shaft 12 by means of screws 20 which are parallel to the drive shaft 12 and the rotary shaft 22 of the flywheel 10 and distributed regularly in a circle around this shaft 22. ing.

  The screw 20 is received in the orifice 24 of the radially inner annular part 26 of the flywheel 10, which annular part 26 is surrounded by an annular mass 26 by two radial arms 28 in opposite positions. 30 and a cylindrical outer peripheral portion that supports the ignition teeth 32.

  In the present embodiment, the annular portion 26, the radial arm 28, and the annular mass member 30 are formed as a single component made of cast iron, eg, ductile cast iron, which is a material that can withstand bending stress.

  The arm 28 is not exactly perpendicular to the rotating shaft 22 but is slightly inclined and extends from the annular portion 26 to the clutch side. This makes it possible to increase the axial rigidity of the flywheel, so that the flywheel can withstand more clutch release force and the number of pumping operations can be increased.

  The radial arm 28 has a width and thickness capable of transmitting the maximum torque generated by the automobile internal combustion engine.

  Further, the radial arm 28 defines a vibration axis 34 orthogonal to the rotation axis 22, and the angular position of the vibration axis 34 about the rotation axis 22 is determined with respect to the drive axis 12 and is known by measurement or calculation. (The angular position of the flywheel 10 relative to the drive shaft 12 itself is constant and is determined by suitable means during assembly).

  The flywheel annulus 26 and the radial arm 28 define a movable element similar to the flexible annular metal plate of a conventional flexible flywheel, which allows bending deformation of the flywheel. (The annular mass member 30 moves parallel to itself).

  The radial arm 28 of the flywheel 10 also allows vibration of this flywheel about the axis 34, which is associated with the bending of the last crankpin of the crankshaft that forms the drive shaft 12.

  The cross section of the radial arm 28 is determined to allow this vibration phenomenon, for example, at the crankshaft vibration frequency corresponding to a rotational speed of about 2700-4500 rpm.

  In one embodiment of the present invention, the friction diameter is 220 mm, the radial arm 28 has an oval or substantially rectangular cross section with rounded ends, and the flywheel has a breaking strength of about 500 Mpa. Made from ductile cast iron, the radial arm 28 has a thickness of 6-10 mm for a width of 30-40 mm. The radial arm connection radius 36 to the annular mass member 30 is determined to reduce stress concentrations, for example about 8 mm.

  The damping in ductile cast iron is about 3-4 times better than that in steel.

  3 and 4, the vibration shaft 34 of the flywheel 10 is symmetrical with respect to the same radial arm 28 as described above and the shaft 34, and is On the other hand, it is defined by the radial arm 28 and two other radial arms 40 that extend in substantially opposite directions. The radial arm 40 forms an angle of about 140 degrees with the radial arm 28 in the illustrated example.

  These two radial arms 40 are slightly easier to cast than the single arm 28 and have fewer problems of removal from the mold.

  In other respects, the structure of the flywheel 10 shown in FIGS. 3 and 4 is the same as the structure of the flywheel of FIGS. 1 and 2.

  In the embodiment of FIGS. 5 and 6, the flywheel 10 is of the type shown in FIGS. 1 and 2 and damps flywheel vibration about an axis 34 defined by the radial arm 28. Is associated with hysteresis means.

  This hysteresis means comprises, for example, an annular spring washer 42 made of spring steel and configured to be fixed to the end of the drive shaft simultaneously with the radially inner annular portion 26 of the flywheel. . For this purpose, the spring washer 42 has an orifice 44 that coincides with the orifice 24 formed in the annular portion 26 so that the fixing screw 20 passes through. The inner diameter of the spring washer 42 is equal to the inner diameter of the annular portion 26 of the flywheel. Almost equal.

  The spring washer 42 has two radial arms 46 at opposite positions that extend in a direction perpendicular to the vibration axis 34. The radially outer end 48 of the radial arm 46 is curved parallel to the axis so as to abut against the inner cylindrical surface 50 of the annular mass member 30 by pressure.

  In such a situation, during operation, any vibration of the annular mass member 30 about the shaft 34 causes friction on the folded end 48 of the arm of the spring washer 42 secured to the radially inner annular portion 26 of the flywheel. Occurs.

  In one variation, the end 48 of the arm 46 extends through a small orifice formed in the web connecting the annular portion 26 to the annular mass member 30.

  In the embodiment of FIGS. 7 and 8, the flywheel 10 according to the invention comprises two independent elements that are fixed to each other, namely a flexible element 52 made of steel plate and an annular mass member made of cast iron. 30. The flexible element 52 has an annular shape as a whole, and is fixed to the mass member 30 at the outer periphery in the radial direction by screws 54, rivets and the like.

  The flexible element 52 includes a radially inner annular portion 56 formed with an orifice 58 through which a fixing screw for fixing the flexible element 52 is fixed to the end of the drive shaft, and a flexible element on the annular mass member 30. A radial outer annular portion 60 having an orifice through which a fixing screw 54 for fixing 52 is passed, and two radial arms 62 at opposite positions connecting the annular portions 56, 60 to each other.

  The flexible element 52 is preferably formed by an annular washer formed with two generally bean-shaped cutouts 64 in opposite positions and defining a radial arm 62 therebetween.

  In general, the flexible element 52 is made from a steel plate that is much thicker than the steel plate forming the flexible element of a prior art flexible flywheel, and this thickness is, for example, about 5 mm. This thickness reduces the risk of deformation of the steel sheet during machining and makes the production of the flexible element 52 easier and simpler.

  As described above, the vibration axis of the flywheel is defined by the symmetric diameter axis of the radial arm 62.

  9 and 10, the flexible element 72 of the flywheel 10 according to the present invention basically has an orifice 76 through which a fixing screw for fixing the flexible element 72 passes through the end of the drive shaft. , And two radial arms 78 of the type previously described that define the flywheel's axis of vibration and have outwardly facing radial extensions 80, these extensions 80. Forms an area for fixing the flexible element 72 to the annular mass member 30 and has an orifice through which a fixing screw 82, a rivet and the like pass.

  A notch or cutout 84 is formed in the side surface of the radial arm 78 to form a region for locating the maximum stress and a region for releasing the maximum stress from the orifice through which the screw 82 passes. .

  FIG. 11 schematically illustrates a continuum of flexible elements, such as element 52 of FIGS. The outer peripheral edge 86 of this continuum has a notch 88 and a tip 90 in opposite positions, which allow the flexible element 52 to be formed into a sheet metal strip. The flexible elements 52 can be partially inserted into each other.

  As shown in FIG. 11, the tip 90 of one element 52 extends into a notch 88 in the next element 52.

  To save space and save material, the tip 90 of each flexible element 52 itself is formed by two curved notches 92 formed in the radially outer annular portion 60 of the flexible element. .

  In the embodiment of FIGS. 12 and 13, the flexible element of the flywheel 10 according to the invention is of the same type as the flexible element 72 of FIGS. Associated with a cross-shaped hysteresis means extending in a plane perpendicular to the abutment and abutting against the element 72.

  This elastic element 96 has two radial arms 98 that are identical in shape to the radial arm 78 of the flexible element 72 and overlap the radial arm 78 in opposite positions, and the radial arms 78, 98. A radial arm 98 having a radially outer end 102 that is pressed against the radial surface of the mass member 30 to provide damping by radial friction when the flywheel vibrates about a defined axis. And two other radial arms 100 perpendicular to.

  The elastic element 96 is fixed to the annular mass member 30 at the end of the radial arm 98 by a fixing screw 82 of the flexible element 72, and the radially inner annular part of the elastic element 96 fixes the flywheel to the drive shaft. And an orifice 104 through which a screw to pass is passed.

  In this embodiment, the flexible element 72 is formed by a stack of elongated flat elements made from sheet metal, and the elastic element 96 forms part of the stack.

  In the embodiment of FIGS. 14, 15, and 16, the flywheel 10 is integrally formed from, for example, cast iron and its radially inner annulus 26 is diametrically opposite, similar to the embodiment of FIGS. It is connected to the annular mass member 30 by two radial arms 28 in position and by a relatively thin annular web 108 that occupies all the space between the annular portion 26, the annular mass member 30 and the radial arm 28. ing. The flexible element of the flywheel is a ring that includes a localized thickness increase that forms the radial arm 28.

  In other respects, the structure of the flywheel is the same as that of FIGS.

  In the embodiment of FIGS. 17 and 19, the flexible flywheel 10 has an annular mass member 30 made of cast iron and a flexible element of the type shown in FIGS. The element is formed from a stack of identical elements 72 made from sheet metal.

  As in the embodiment of FIGS. 9 and 10, the flexible element is secured to the annular mass member 30 at the end 80 of the radial arm 78 that defines the axis of vibration by screws 82, rivets, and the like. .

  As can be seen more clearly in FIG. 19, the stack of identical elements 72 abuts the annular sheet metal 110 that is secured to the annular mass member 30 by a securing screw 82 for securing the flexible element 72. . The circumference of the annular metal thin plate 110 is in contact with the radial surface of the annular mass member 30 to form hysteresis means for damping the flywheel bending and vibration.

  The stacked elements 72 have different thicknesses and are thicker in the center than the ends of the stack to balance bending stresses. The hardness of the stacked elements can be changed.

  In the embodiment of FIGS. 20 and 21, the flexible flywheel 10 is integrally formed and, as in the previous embodiment, is attached to the annular mass member 30 by two radial arms 28 in opposite positions. Two radial tabs 112 having a connected radially inner annular portion 26 and perpendicular to the vibration axis 34 defined by the radial arm 28 and extending from the annular portion 26 to the annular mass member 30 side. Have.

  The annular mass member 30 has two radial tabs 114 facing the annular portion 26 side from the cylindrical inner surface of the annular mass member 30, and the radial tabs 112, 114 are aligned and face each other in pairs. Ends in a cylindrical housing.

  The housing contains means such as a spring pin 116 that forms hysteresis means for dampening flywheel vibration about the shaft 34. In general, the hysteresis means comprises an intermediate element mounted between the annular part 26 and the annular mass member 30 in a direction perpendicular to the axis 34.

  In the embodiment of FIG. 22, the flexible flywheel 10 includes an orifice 24 through which a fixing means for fixing the flexible flywheel 10 to a drive shaft passes, and four radial arms 28 of the type described above. It has a radially inner ring formed. The radial arms 28 are arranged at 90 degrees to each other and are connected to the annular mass member 30 at the radially outer ends by elastically deformable lugs 120, 122. The lug extends in a plane perpendicular to the rotation axis and is fixed to the radial arm 28 and the annular mass member 30 at the end by screws, rivets and the like.

  In the illustrated embodiment, each lug 120, 122 is elongated and extends in a direction generally perpendicular to the fixed radial arm 28.

  Thus, two vibration axes 34, 124 of the flexible flywheel perpendicular to the axis of rotation and orthogonal to each other are defined, one of these vibration axes corresponding to said axis 34 and the other 124 being the axis 34 Is perpendicular to.

  The rigidity of the lug 120 secured to the radial arm 28 defining the vibration axis 124 is lower than the rigidity of the lug 122 secured to the radial arm 28 defining the vibration axis 34. Thus, it can have two vibration frequencies centered on two vertical axes, each at an angular position defined with respect to the drive axis.

  The vibration centered on the shaft 34 is characterized by low stiffness and resulting low frequency. The vibration centered on the shaft 124 is characterized by high rigidity and high frequency.

  This same result is obtained by providing different mass members that produce different inertias on the two vibrating axes 34,124. When the mass member arranged on one vibration axis is larger, the vibration frequency is lower than when the axis is perpendicular to the vibration axis.

  It is also possible to combine these two means, i.e. to distinguish between the rigidity of the lugs 120, 122 and the mass member arranged on the vibration axis.

  As a variant, the arm 28 on the shaft 124 can be connected to the annular mass member 30 by two lugs 120 and the lugs 122 can be eliminated so that the lugs 120 assist in the transmission of torque.

  In the embodiment of FIGS. 23-26, the flexible flywheel according to the invention forms part of a double flywheel damper and forms the primary flywheel of the double flywheel damper.

  In FIG. 23, the flexible primary flywheel 10 has a radially inner annular portion 26 that forms a hub, which includes a radially inner annular portion of a flexible annular metal plate 132. Is fixed by a rivet 130, and the radial outer periphery of the annular metal plate 132 is axially clamped onto an annular mass member 30 formed by two cylindrical rings 134, 136, one welded to the other. The outer periphery of the annular metal plate 132 is clamped between the axial end of the inner ring 134 and the edge of the outer ring 136.

  Hysteresis means is associated with this flexible annular metal plate and is formed by a spring washer 138. The radial outer periphery of the spring washer 138 is clamped to the radial outer periphery of the annular metal plate 132 between the rings 134 and 136 as shown, and the radially inner annular portion of the spring washer 138 is the flexible annular metal plate 132. Including a radial tab 140 that resiliently abuts.

  The flexible primary flywheel 10 is associated with a secondary flywheel 142, which is centered on the hub 26 and rotatably guided by a smooth bearing 144, which is a conventional type of clutch. A reaction plate is formed.

  A damping damper 146 with a circumferential spring is mounted between the two flywheels, allowing angular movement between the two flywheels and connecting them both in rotation to reduce vibration and torque variations. It is designed to absorb.

  This vibration damping damper has an input element that is rotatably fixed to the primary flywheel 10 and an output element that is rotatably fixed to the secondary flywheel 142 as in the prior art. 148 is fixed to the spring washer 138, and the output element is fixed to the secondary flywheel by the rivet 150.

  A torque limiter is formed by clamping the outer periphery of the annular metal plate 132 between the rings 134 and 136 of the annular mass member 30 in the axial direction, and a torque transmitted by the axial clamp is a predetermined maximum value. The annular metal plate 132 can be rotated relative to the spring washer 138.

  In the variant shown in FIG. 24 which is an axial half section view of a flexible primary flywheel of a double flywheel damper, the primary flywheel 10 has a flexible annular metal plate 152, The radial interior is secured to the end of the drive shaft by screws 154 at the same time as the cylindrical hub forming the inner annular portion 26 of the flexible flywheel, and the radially outer annular portion of the annular metal plate 152 is a rivet. It is fixed to the cast iron annular mass member 30 by 156.

  The annular mass member 30 supports the ring gear and the closing plate 158 on the side opposite to the drive shaft. The closing plate 158 has an inner peripheral edge 162 that is fixed to the annular mass member 30 by a rivet 160 and that faces in the radial direction and is located close to the flexible annular metal plate 152.

  A spring washer 164 is mounted between the flexible annular metal plate 152 and the edge 162 of the closure plate 158 and forms a hysteresis means for dampening the bending vibrations of the primary flywheel 10.

  In the variant of FIGS. 25 and 26, the double flywheel damper shown in axial section is constituted by a flexible primary flywheel 10 according to the invention and two annular parts 172, 174 connected to each other by a torque limiter 176. Rolling bearing for centering and rotatably guiding the secondary flywheel 170 on the cylindrical hub formed by the formed secondary flywheel 170 and the radially inner annular portion 26 of the primary flywheel 10. 178 and a damping damper 180 of the type that is mounted between two flywheels and that has a radial type or a radial spring.

  In a known manner, the damping damper spring 182 is guided on a cylindrical rod 184 housed in a cylindrical casing 186. The radially outer end of this cylindrical rod 184 is mounted to pivot on the annular mass member 30 of the primary flywheel about an axis 188 that is parallel to the axis of rotation, and is radially inward of the cylindrical rod 184. The end is mounted to pivot on the inner annular portion 174 of the secondary flywheel 170 by an axis 190 parallel to the axis of rotation.

  An annular mass member 30 of the primary flywheel includes a block 192 made of cast iron, housed between the cylindrical casings 186 of the dampers of the damping damper and having a generally triangular shape with the top facing the rotational axis. The angular movement of the cylindrical casing about the shaft 188 of the joint portion of the mass member 30 is made possible.

  As described with reference to FIG. 22, the mass of the block 192 is distributed on the two vertical vibration axes 34, 124.

  The block 192 is fixed to the metal plate 196 of the annular mass member 30 of the primary flywheel by a rivet 194 simultaneously with the radial outside of the flexible annular metal plate 132 of the primary flywheel.

  A spring washer 198 is attached between the annular metal plate 132 and the radial edge 200 of the metal plate 196 on the primary flywheel side facing the drive shaft side. This spring washer forms a means for damping the bending vibration of the primary flywheel.

  The embodiment shown in FIG. 26 differs from the embodiment of FIG. 25 only in the formation of the block 192 supported by the primary flywheel. In this case, the block is composed of the metal plates 202 stacked in the axial direction, which are fixed to the metal plate 196 of the primary flywheel by the rivets 194 simultaneously with the radially outer peripheral portion of the flexible annular metal plate 132. Yes.

  In other respects, the structure is the same as that described with reference to FIG.

  The positioning of the flexible flywheel according to the present invention on the drive shaft will be described in more detail with reference to FIG.

  The drive shaft 12 is a crankshaft including at least one crankpin 1200, 1201 that can be connected to at least one connecting rod (not shown) associated with the piston of the heat engine. A crankpin, referred to as first crankpin 1200, is adjacent to the flexible flywheel 10 according to the present invention. The crankpin 1200 defines a plane P that includes the drive shaft and the rotational shaft 22 of the flexible flywheel 10.

  As described above, the vibration shaft 34 of the flexible flywheel 10 according to the present invention is substantially perpendicular to the rotation shaft 22 and is positioned at an angle with respect to the drive shaft 12. This angular position is determined between the plane P and the vibration axis 34, and has a positioning angle α between them.

  The value of the positioning angle α is optimized so that the drive shaft stress or the noise generated by the engine can be reduced. The value of the positioning angle α is obtained by measurement or calculation. This value depends on the number of cylinders of the heat engine and the arrangement of the cylinders. This value also depends on the phenomenon (basically stress and noise) that it is desirable to reduce. Furthermore, the value of the positioning angle α is measured in the rotational direction R of the drive shaft from the plane P to the vibration shaft 34 of the flexible flywheel 10 according to the invention.

  For example, when the vibration shaft 34 is close to the normal of the plane P (that is, the value of the positioning angle α is equal to about 90 °), this position can mainly reduce the stress of the crankshaft.

  In a heat engine, the crankpin that supports the piston is considerably larger than the angle with the perpendicular of about 15 ° to 20 ° in the rotational direction, that is, the so-called disassembly angle (the angle with the perpendicular that the crankpin takes during disassembly). It has been found that a maximum pressure is exerted on the piston head when forming the angle. Noise can be reduced by the displacement of the flexible flywheel 10 according to the present invention by about 15 ° to 20 ° in the rotational direction of the drive shaft.

  Therefore, the value of the positioning angle α can be about 80 ° to about 120 °. Thereby, an emphasis can be placed on the reduction of noise generated with respect to the reduction of stress, and an emphasis can be placed on the reduction of stress with respect to the reduction of generated noise.

  The value of the positioning angle α is preferably about 90 ° to 110 °. At a positioning angle α value of about 90 °, the stress is reduced, and at a positioning angle α value of about 110 °, the generated noise is reduced. Due to the intermediate value of the positioning angle α, it is possible to adapt the reduction of stress and the reduction of generated noise as desired.

It is a schematic front view of the flexible flywheel by this invention. FIG. 2 is a schematic sectional view in the axial direction of the flywheel of FIG. 1. It is a figure similar to FIG. 1 about the deformation | transformation form of a flexible flywheel. It is a figure similar to FIG. 2 about the deformation | transformation form of a flexible flywheel. It is a figure similar to FIG. 1 about another modification. It is a figure similar to FIG. 2 about another modification. FIG. 6 is an axial schematic cross-sectional view of another variation of a flexible flywheel. It is a schematic perspective view of the flywheel of FIG. It is a figure similar to FIG. 1 about another modification of this invention. It is a figure similar to FIG. 2 about another modification of this invention. FIG. 2 is a schematic diagram showing the arrangement of continuous flexible elements in a metal strip before cutting. FIG. 6 is a schematic elevation view of another variation of a flexible flywheel. It is a schematic perspective view of the flywheel of FIG. FIG. 6 is a schematic front view of another variation of a flexible flywheel. It is a schematic sectional drawing in the XV-XV line | wire of FIG. It is a schematic sectional drawing in the XVI-XVI line of FIG. FIG. 6 is a schematic front view of yet another variation of a flexible flywheel. FIG. 18 is a schematic axial sectional view of two vertical surfaces of the flywheel of FIG. 17. FIG. 18 is a schematic axial sectional view of two vertical surfaces of the flywheel of FIG. 17. FIG. 6 is a schematic front view of yet another variation of a flexible flywheel. FIG. 21 is an enlarged schematic axial sectional view of the flywheel of FIG. 20. FIG. 6 is a schematic front view of another variation of a flexible flywheel according to the present invention. 1 is a schematic axial sectional view of a double flywheel damper according to the present invention. It is an axial direction general | schematic cross-section half view of the deformation | transformation form of a double flywheel damper. FIG. 4 is a schematic axial sectional view of a modified form of a double flywheel damper according to the present invention. FIG. 4 is a schematic axial sectional view of a modified form of a double flywheel damper according to the present invention. FIG. 2 is a schematic diagram of the flywheel of FIG. 1 showing positioning with respect to a drive shaft.

Explanation of symbols

12 Drive shaft 22 Rotating shaft 24 Orifice 26 Central ring, inner annular portion 28, 38, 40, 42, 78, 100 Radial arm 28 Means 30 Annular mass member 34, 124 Vibrating shaft 42, 100, 102, 110 Hysteresis means 42 Washer 48 Radial outer end 54, 82 Screw 64 Cutout 72 Flat element 84 Notch 96 Element 112, 144 Tab 116 Spring pin 120, 122 Lug 142, 170 Flywheel 146, 180 Damping damper 182 Spring

Claims (29)

An annular mass member (30) configured to be driven about a rotating shaft (22) by a drive shaft (12) and supported by a flexible element configured to be fixed to the drive shaft. A torque transmission device, in particular a flexible flywheel of an automobile,
The flywheel characterized in that the flexible element comprises a radial arm (28) defining a vibration axis (34) perpendicular to the rotational axis (22) of the flywheel.   The flywheel according to claim 1, characterized in that the vibration shaft (34) has a predetermined angular position with respect to the drive shaft (22).   3. Flywheel according to claim 1 or 2, characterized in that the radial arm (28) extends between the axis of rotation (22) and the annular mass member (30).   The said vibrating shaft (34) is formed by two radial arms extending continuously from each other between the rotating shaft and the annular mass member (30). The flywheel according to any one of the above.   The vibration axis (34) is formed by three radial arms (28) (40), the two radial arms being symmetrical with respect to the extension of the third radial arm (28). The flywheel according to claim 1, wherein the flywheel is provided.   The flywheel according to any one of claims 1 to 5, characterized in that the flexible element is annular and includes cutouts (64) on both sides of the vibration axis.   The flywheel according to claim 6, characterized in that the cutout (64) passes therethrough.   The flywheel according to any one of claims 1 to 7, characterized in that the flexible element is formed integrally with the annular mass member (30).   The flywheel according to any one of claims 1 to 8, characterized in that the flexible element is made of cast iron.   9. Flywheel according to any one of the preceding claims, characterized in that the flexible element is made from steel.   The flexible element is a separate part and is fixed to the annular mass member (30) at the end of the radial arm by screws (54) (82), rivets or the like. The flywheel according to claim 10.   12. Fly according to claim 10 or 11, characterized in that the flexible element is formed by a plurality of flat elements (72) which are superposed and secured together to the annular mass member (30). wheel.   The radial arm (38) defining the vibration axis (34) is connected to a central ring (26) at a radially inner end, the central ring for fixing the central ring to the drive shaft. 13. A flywheel according to any one of the preceding claims, characterized in that it has an orifice (24) through which the fixing means passes.   14. Hysteresis means (42) (100) (102) (110) supported by the flexible element and cooperating with the annular mass member (30) by friction. The flywheel described in any one.   The hysteresis means includes a radially inner end integral with the flexible element, perpendicular to the vibration axis (34), and a radially outer end (48) contacting the annular mass member (30). 15. Flywheel according to claim 14, characterized in that it comprises two radial arms (42) having.   16. Flywheel according to claim 15, characterized in that the radial arm of the hysteresis means forms part of the flexible element.   The flexible element (72) has a stack of flat elements and the radial arm (100) of the hysteresis means is formed on one element (96) of the stack. The flywheel according to claim 16.   A flywheel according to claim 15, characterized in that the radial arm of the hysteresis means forms part of a washer (42) attached to the flexible element.   19. Flywheel according to claim 18, characterized in that the washer (42) is configured to be fixed to the drive shaft together with the flexible element.   The hysteresis means includes an intermediate element mounted in a direction orthogonal to the axis (34) between the annular mass member (30) and the inner annular portion (26) of the flexible element. The flywheel according to claim 14.   The hysteresis means is a spring pin mounted in a semi-cylindrical housing of two tabs (112) integral with the flexible element and two tabs (144) integral with the annular mass member (30). 116) and fly tabs according to claim 14, characterized in that the tabs extend in a direction perpendicular to the vibration axis (34).   The radial arm (78) defining the vibration axis has a cutout or notch (84) for positioning the maximum stress between the radially inner end and the radially outer end. The flywheel according to any one of claims 1 to 21.   The radial arm (28) defining the vibration axis (34) is inclined slightly in the direction opposite to the drive axis from a radially inner end with respect to a normal to the rotation axis. The flywheel according to claim 1, characterized in that:   The flexible element includes means (28) defining a second vibration axis (124) orthogonal to the rotational axis (22) and the advantageous vibration axis (34), the second vibration axis ( 24. Flywheel according to any of the preceding claims, characterized in that the stiffness of 124) is higher than the stiffness of the advantageous vibration axis (34).   25. Flywheel according to claim 24, characterized in that the two vibration axes (34) (124) are defined by radial arms (28) of the flexible element.   26. Flywheel according to claim 25, characterized in that the radial arm (28) is connected to the annular mass member (30) by lugs (120) (122).   The lug (120) connecting two aligned radial arms to the annular mass member (30) connects the two other radial arms (28) to the annular mass member (30). 27. Flywheel according to claim 26, characterized in that it has a different stiffness than the lug (122).   A secondary flywheel (142) (170) configured to form a primary flywheel of a double flywheel damper, the double flywheel being connected to the input shaft of the transmission, and the two flywheels The flywheel according to any one of claims 1 to 27, further comprising damping dampers (146) (180) attached between the wheels.   29. Flywheel according to claim 28, characterized in that the damping damper (180) is of the type having a spring (182) facing radially in the remaining part.

Images