WO2013153219A1

WO2013153219A1 - Transmission pulley for a motor vehicle accessory, method for producing and method for dismantling such a pulley

Info

Publication number: WO2013153219A1
Application number: PCT/EP2013/057736
Authority: WO
Inventors: Bernard Lacoste; Nicolas Houziaux
Original assignee: Tech-Form
Priority date: 2012-04-13
Filing date: 2013-04-12
Publication date: 2013-10-17
Also published as: FR2989442A1; FR2989442B1; JP2015516549A; EP2836742A1

Abstract

The present invention relates to a transmission pulley (1) for a motor vehicle accessory, in particular for an air-conditioning compressor. Said pulley (1) includes a hub centered about a central axis (X1) and capable of being secured to a shaft which is part of the motor vehicle accessory, a gear including a radial rim (22) and an outer peripheral track (24) for driving the gear in rotation by means of a belt, an annular insert 40), and means (60) for coupling the annular insert (40) to the gear (20). The pulley is characterized in that the coupling means (60) are distributed (27, 28) over the gear (20) and (43, 44) over the annular insert (40), and are adjustable between a coupled configuration in which the annular insert is rotatably mounted to the gear about the central axis (X1) and free to move in translation relative to the gear along said axis (X1), the coupling means (60) allowing an axial clearance parallel to the axis (X1) between the gear and the annular insert, and an uncoupled configuration in which the annular insert can be separated from the gear. The invention further relates to a method for producing such a pulley (1) and to a method for disassembling same.

Description

TRANSMISSION PULLEY FOR AUTOMOTIVE ACCESSORY, MANUFACTURING METHOD AND METHOD FOR DISASSEMBLING SUCH PULLEY

The present invention relates to a transmission pulley for automobile accessories, in particular for an air conditioning compressor. The invention also relates to a manufacturing method and a method of dismounting such a pulley.

The field of the invention is that of pulley and belt transmission systems, more specifically torsion damping pulleys for automotive accessories.

In known manner, a pulley and belt system is positioned between a motor shaft, for example a crankshaft, and one or more rotary members conducted. In particular, the driven member may be a motor vehicle accessory, for example an alternator, a cooling pump or an air conditioning compressor. The shaking and vibrations to which the drive shaft is subjected are transmitted to the pulley and belt system, as well as to the accessory driven by this pulley, which accelerates their wear and may cause malfunctions. In addition, the accessories can be degraded by excessive acyclisms during variations in the rotational speed of the system, due to the reduction ratios provided in the design of the front of the accessories. For example, the speed variation of an alternator is about 3 times higher than that of a crankshaft.

EP-A-0 790 440 discloses a transmission pulley, adapted to be wedged on a crankshaft of an engine or reciprocating piston machine. The pulley comprises a hub, an outer ring receiving a belt, and an antivibration ring fixed between the hub and the ring. This pulley ensures a satisfactory damping of the torsional vibrations and an effective filtration of the vibrations of acyclism at low revolutions. This pulley, however, is not expected to undergo a large number of assemblies and disassembly, which may accelerate its wear.

US-A-2006 194 663 describes various embodiments of a transmission pulley for automobile accessory. In particular, this document describes as a state of the art a pulley comprising a hub, a ring, an annular insert, an elastically deformable member, as well as coupling screws of the annular insert with the ring. These screws are additional parts that complicate assembly and disassembly of the constituent elements of the pulley. The transition from a coupled configuration to an uncoupled configuration requires the use of a tool to tighten and loosen the screws. In the coupled configuration, the screws are tightened to press the annular insert against the crown. The annular insert is then integral in rotation of the ring around the central axis, but not free in translation along the central axis. If the screws were not tight, it would result in noise and degradation of the constituent elements of the pulley.

DE-A-103 11 367 describes other embodiments of a transmission pulley for automobile accessories. The coupling means of the annular insert with the crown comprise leaf springs, which are additional parts complicating the assembly and disassembly of the constituent elements of the pulley. In coupled configuration, because of the pressure exerted by the leaf springs on the annular insert, it is integral in rotation with the ring about the central axis, but not free in translation along the central axis .

The object of the present invention is to provide an improved pulley.

For this purpose, the subject of the invention is a transmission pulley for an automobile accessory, in particular for an air conditioning compressor, this pulley comprising a hub centered on a central axis and adapted to be secured to a shaft belonging to the automobile accessory. , a ring comprising a rim which extends radially to the central axis and an outer peripheral race for rotation of the ring by a belt, an annular insert secured in rotation with the hub, and coupling means of the annular insert with the crown. The pulley is characterized in that the coupling means of the annular insert with the ring are distributed, on the one hand, on the ring and, on the other hand, on the ring insert, and are adjustable between a configuration coupled where the annular insert is integral with the ring in rotation about the central axis and free in translation relative to the ring along the central axis, the coupling means allowing axial play parallel to the axis central between the ring and the annular insert, and a disengaged configuration where the annular insert is separable from the ring.

Thus, the invention facilitates assembly and disassembly of the constituent elements of the pulley, thanks to the coupling means distributed on the one hand, on the ring and on the other hand, on the annular insert. With this distribution, the number of elements handled during the assembly of the pulley is reduced in comparison with coupling means comprising screws, metal blades or other additional parts. Due in particular to the presence of axial play, the coupling means make it possible to validate the mountability of the pulley over a wide range of manufacturing tolerances and to simplify the mounting station for the annular insert on the ring. The pulley operates optimally in the coupled configuration, with its various components that are rotated about the central axis. The transition from the coupled configuration to the uncoupled configuration, which corresponds to a disassembly of at least a part of the pulley, can be carried out manually in a simple, fast and practical way, and inversely when passing from the uncoupled configuration to the coupled configuration, without any screw connection and without requiring specific tools . Thanks to the coupling means according to the invention, the pulley is adapted to support a large number of assembly and disassembly operations during its lifetime, in particular without degrading the elastically deformable member that can be interposed between the annular insert and the hub and without decreasing the overall performance of movement and torque transmission of the pulley. The life of this pulley is improved.

The invention is particularly well suited for the drive of air conditioning compressors, including variable displacement compressors, which are permanently driven by the pulley while their compression ratio varies according to demand.

According to other advantageous features of the invention, taken separately or in combination:

- The pulley also comprises an elastically deformable member positioned around the central axis between the annular insert and an outer surface of the hub.

In the coupled configuration, the coupling means exclude any rotational play around the central axis between the ring and the annular insert.

- The coupling means comprise flexible tabs in a direction radial to the central axis and in a direction axial to the central axis, the assembly and when the pulley is in use.

- The coupling means are adjustable without screwing between the coupled configuration and the uncoupled configuration

- The coupling means are adjustable from the coupled configuration to the uncoupled configuration by traction on the annular insert in a generally axial direction opposite to the ring, in particular without the use of a specific tool.

- The coupling means comprise at least a portion which, in the coupled configuration, is plastically deformable, brittle or fusible when the pulley is subjected to an overtorque exceeding a predetermined threshold torque, the plastic deformation, rupture or melting of this part bringing the ring and the annular insert into uncoupled configuration.

- The coupling means comprise at least one member integral with the annular insert or the ring gear and at least one orifice formed in the ring or in the annular insert, adjustable from the uncoupled configuration to the coupled configuration by mechanical cooperation, in particular by clipping. - The coupling means comprise at least one member which extends radially and / or axially central axis from a portion of the annular insert, and at least one orifice formed in the ring in a substantially radial or substantially axial direction by relative to the central axis, preferably several orifices distributed around the central axis, the orifice or each orifice being adapted, in coupled configuration, to receive at least partially the organ or one of the organs belonging to the annular insert.

- The coupling means comprise an elastically deformable jumper, an axial pin and / or a radial lug.

- The coupling means comprise orifices distributed in the ring around the central axis and adapted to receive integral members of the annular insert, and in that an angular offset is provided between at least one of the organs and the orifice receiving this member when the other members are positioned in the other orifices in coupled configuration, this angular offset excluding any rotational play around the central axis between the ring and the annular insert in the coupled configuration.

The invention also relates to a method of manufacturing a pulley as mentioned above. This manufacturing method is characterized in that it comprises at least steps consisting of:

a) manufacture the hub;

b) manufacturing the ring provided with the rim, the outer peripheral track and a first portion of the coupling means with the annular insert;

c) manufacturing the annular insert having a second portion of the coupling means with the ring;

e) securing in rotation about the central axis the annular insert to the hub; and f) securing the annular insert to the ring in the coupled configuration by adjusting the coupling means.

Steps a), b) and c) are performed before step e), which is performed before step f) -

In the case where the pulley comprises an elastically deformable member: in step a), the hub includes an outer surface adapted to receive this elastically deformable member; the method also comprises a step d) of manufacturing the elastically deformable member; step e) comprises the following substeps e1) and e2) consisting of:

e1) positioning the elastically deformable member against the outer surface of the hub; and

e2) positioning the elastically deformable member against the annular insert. The invention also relates to a dismounting method of a pulley manufactured using the manufacturing method mentioned above. This disassembly process is characterized in that it comprises a step g) of separating the annular insert from the ring at the coupling means, from the coupled configuration to the uncoupled configuration, by pulling on the annular insert. in a generally axial direction opposite the crown.

The invention will be better understood on reading the description which follows, given solely by way of nonlimiting example and with reference to the appended drawings in which:

- Figure 1 is a perspective view of a pulley according to the invention;

Figure 2 is a side view along the arrow II in Figure 1;

Figure 3 is a rear view along the arrow III in Figure 2;

- Figure 4 is a front view along the arrow IV in Figure 2;

- Figure 5 is a section along the line V-V in Figure 4;

Figure 6 is an enlarged view of Detail VI in Figure 1;

- Figure 7 is a section along the line VI-VI in Figure 4;

- Figure 8 is a partial section, similar to Figure 5, a pulley according to a second embodiment of the invention;

Figure 9 is a partial view, similar to Figure 4 and on a larger scale, showing the pulley of Figure 8;

Figure 10 is a section along line X-X in Figure 9;

- Figure 11 is a view similar to Figure 4, on a smaller scale, a pulley according to a third embodiment of the invention;

Figure 12 is a section along line XI-XI in Figure 11;

- Figure 13 is a view similar to Figure 8 of a pulley according to a fourth embodiment of the invention;

Figure 14 is a view similar to Figure 1 1 showing the pulley shown in Figure 13;

Figure 15 is a section along line XV-XV in Figure 14;

- Figure 16 is a view similar to Figures 8 and 13 of a pulley according to a fifth embodiment of the invention;

Figure 17 is a view similar to Figures 11 and 14 showing the pulley of Figure 16;

- Figure 18 is a section along the line XVIIl-XVIil in Figure 17; and

- Figure 19 is a view similar to Figure 16 of a pulley according to a sixth embodiment of the invention. In Figures 1 to 7 is shown a transmission pulley 1 according to the invention.

The pulley 1 is adapted to be driven by a belt C and to drive a shaft A. The belt C and the shaft A are shown partially, only in Figure 2, for the sake of simplification. In this case, the shaft A belongs to an air conditioning compressor, not shown. The belt C is driven by a first pulley wedged on a motor shaft, for example a crankshaft, also not shown. The pulley 1 and the belt C form a system for transmitting a torque and a rotational movement M1 to the shaft A of the air conditioning compressor.

In addition or alternatively to the air conditioning compressor, the pulley 1 is adapted to drive one or more automotive accessories such as an alternator or a cooling pump.

The pulley 1 comprises a hub 10, a ring 20, an antivibration ring 30 and an annular insert 40, which are integral in rotation M1 around the central axis X1. The pulley 1 also comprises a bearing 50, which is housed in an inner portion 21 of the ring 20 and centered on the axis X1. The pulley 1 also comprises means 60 for coupling the insert 40 with the ring 20, adjustable between a coupled configuration and a disengaged configuration, as detailed below.

Thereafter, there is defined an inner side directed radially to central axis X1 and an outer side directed radially away from the central axis X1. For a given component of the pulley 1, an inner portion is closer to the axis X1 than an outer portion. It also defines a front side of which are located the hub 10, the ring 30 and the insert 40, and a rear side of which are located the bearing 50 and the compressor shaft A.

The hub 10 is preferably of metal and comprises an inner portion 11, a radial portion 12 and an outer portion 13. The radial portion 12 extends perpendicularly to the axis X1 between the portions 11 and 13. The outer portion 13 presents an annular shape and has an outer cylindrical surface 14 provided for receiving the antivibration ring 30, as detailed below. The inner part 1 1 is provided to be secured to the shaft A. As shown in Figure 5, the inner portion 1 comprises a bore 11a, a front shoulder 11b, 11c splines and a rear mopping 11d. The hub 10 is a piece of revolution centered on the axis X1, except at the splines 1c.

When mounting the hub 10 on the shaft A, this shaft A cooperates with the flutes 11c and bears against the shoulder 11d. A washer D is preferably disposed in the bore 11a at the end of the shaft A and bearing against the shoulder 11b. A nut E is screwed to the end of the shaft A, until it bears against the washer D. The shaft A is then pressed against the shoulder 11d by tightening the nut E at its end. .

The ring 20 is preferably of metal and comprises an inner portion 21, a radial rim 22 and an outer portion 23. The inner portion 21 is provided to receive the housing, while the outer portion 23 has an outer peripheral track 24 provided for To this end, the track 24 comprises an axial series of V-shaped radial grooves or grooves 25 adapted to cooperate with the belt C or any other endless element led or driving. In this case, this transmission element itself includes complementary V grooves of the grooves 25. The diameter of the track 24 can be measured on the outside of two calibrated balls B, shown only in FIG. 5 and which are each engaged in a groove 25 of the track 24, in application of the ISO 9981 standard. The track 24 is preferably machined or cold formed, depending on the method used to manufacture the crown 20. Two edges 26 extend in projection from the outer portion 23, respectively front side and rear side, along the track 24 to promote the maintenance of the belt C on this track 24. Alternatively, the portion 23 may comprise a single border 26, or no border.

The ring 20 also comprises a part of the coupling means 60, namely openings 27 and lugs 28 formed in the rim 22. More precisely, the rim 22 comprises three pairs of openings 27 traversing axially from front to rear. rear, each pair of openings 27 flanking a tab 28 which extends radially to the axis X1 between an inner edge and an outer edge of the rim 22. The tabs 28 are distributed on the rim 22 at 120 ° around XL These elements 27 and 28, belonging to the coupling means 60 formed on the ring 20, are adapted to cooperate with another part of the coupling means 60 formed on the insert 40, as detailed below. The ring 20 is a piece of revolution centered on the axis X1, except at the level of the openings 27 and lugs 28 formed in the rim 22.

As shown in Figure 5, the bearing 50 comprises an outer ring 51 integral with the ring 20, an inner ring 52, and rolling elements 53 disposed between the rings 51 and 52. The outer ring 51 is mounted in an inner bore of the inner portion 21 of the ring 20. The inner ring 52 is mounted on a compressor casing, not shown in the figures, which surrounds the compressor shaft A. Thus, the ring 20 and therefore the pulley 1 are mounted movably rotating on the compressor housing, while driving the compressor shaft A. The antivibration ring 30 is an elastomer ring, or any other deformable material elastically under the conditions of use of the pulley 1. The ring 30 is preferably made by injection or, alternatively, according to any method suitable for the present application. The ring 30 has an outer surface 31 integral with the insert 40 and an inner surface 32 integral with the outer surface 14 of the hub 10. These rigid connections can be made by press fitting, gluing, bonding, heat sealing, welding and / or any other means suitable for this application. For example, the ring 30 can be fitted on the outer part 13 of the hub 10, then covered and tightened by the insert 40. Thus, during the rotational movement M1 of the pulley 1 about the axis X1, the ring 30 is secured to the hub 10 and the insert 40. The hub 10 is itself secured to the shaft A, while the insert 40 is itself secured to the ring 20, in the coupled configuration of the means of coupling 60, as detailed below. The ring 30 has a stiffness which is of the order of 5 to 10 Nm, so as to ensure the rotation of the shaft A while limiting the variations of regime.

The pulley 1 preferably comprises this antivibration ring 30, but alternatively, the pulley 1 may be devoid of antivibration ring 30. In this case, the annular insert 40 is secured in rotation M1 with the hub 10 by any suitable means, for example example of the spring washers, splines formed on the hub, or anti-rotation flats combined with an axial support secured by crimping

The directory insert 40 is preferably made of metal and comprises an inner cylindrical surface 41, a rear radial face 42, three tabs 43 and three jumpers 44. The surface 41 is integral with the surface 31 of the ring 30, as detailed below. above. The three tabs 43 extend from the face 42 of the insert 40, first in a rear axial direction and then in an outer axial direction. In other words, the three tabs 43 are curved towards the rear and the top of the pulley 1. These tabs 43 are thicker in a direction orthoradial to the axis X1 than in a radial direction and in an axial direction to this axis X1 . Under these conditions, these lugs 43 are slightly flexible in the radial direction and in the axial direction, the assembly and when the pulley 1 is in use, but not flexible in the orthoradial direction. Each tab 43 has, at its end opposite the face 42, one of the riders 44 generally having a U-shape. More specifically, each rider 44 comprises a base 45 integral with the tab 43, as well as two tabs 46 that are elastically deformable. extend from the base 45 in the rear direction. The tabs 43 and the jumpers 44 are distributed on the insert 40 at 120 ° around the axis X1. The insert 40 is a piece of revolution centered on the axis X1, except at the tabs 43 and riders 44. Thus, the insert 40 comprises a portion of the coupling means 60, namely the tabs 43 and the jumpers 44, adapted to cooperate with the other part of the coupling means 60 formed on the ring 20, namely the openings 27 and the tabs 28. The jumpers 44 can be introduced into the openings 27, with the tabs 46 which enclose the tabs 28, by simple axial pressure exerted from front to rear on the insert 40. The flexible tabs 46 have a lower spacing in the configuration uncoupled to the spacing they have, after deformation on either side of the tabs 28, in the coupled configuration of the means 60.

During the assembly or reassembly of the pulley 1, passing from the uncoupled configuration to the coupled configuration, the flexible tabs 46 are clipped into the openings 27 and mechanically cooperate with the tabs 28. The insert 40 is then integral with the 20 rotating ring M1 about the axis X1, but free in translation relative to the ring 20 along the axis X1. The connection between the insert 40 and the hub 10 prevents the insert 40 from accidentally separating from the ring 20 because of this freedom in translation. The belt C transmits the rotational movement 1 to the ring 20, then this movement M1 is transmitted to the insert 40, then to the ring 30, then to the hub 10, then to the compressor shaft A. Within the pulley 1 and the transmission system, in operation, the effects of vibration and acism are attenuated mainly by the antivibration ring 30. In this coupled configuration, the means 60, on the one hand, allow an axial play parallel to the axis X1 between the ring 20 and the insert 40 and, on the other hand, exclude any rotating play around the axis X1 between the ring 20 and the insert 40. The noise when the pulley 1 is in use are reduced by the exclusion of this axial clearance. In particular, because of the presence of this axial clearance, the coupling means 60 according to the invention have the advantages of not generating mechanical stress in service other than those in the ring 30, related to the effects of the torsion during the rotation, validate the mountability of the pulley 1 in a wide range of manufacturing tolerances and simplify the mounting station of the insert 40 with the ring 20.

When disassembling the pulley 1, passing from the uncoupled configuration to the coupled configuration, the nut E is unscrewed to separate the hub 10 from the shaft A. At this stage, a simple manual pull on the insert 40, in a generally axial direction opposite to the ring gear 20, that is to say from the rear to the front of the pulley 1, is sufficient to separate the insert 40 and the ring gear 20 at the coupling means 60 , without requiring special tools. By elastic deformation, the flexible tabs 46 of the jumpers 44 move apart and slide on the tabs 28, until out of the openings 27. In other words, the elements 27, 28 and 44 form means 60 reversible mechanical coupling of the insert 40 and the ring 20. In the uncoupled configuration, the assembly 10-30-40 comprising the hub 10, the ring 30 and the insert 40, is separable from the assembly C -20-50 comprising the belt C, the ring 20 and the bearing 50. If necessary, the belt C and the ring 20 are also removable from the compressor, while the bearing 50 remains in place on the housing. The pulley 1 can therefore be completely dismounted from the compressor, then reassembled, in a simple and practical manner thanks to the means 60.

The invention also relates to a method of manufacturing the pulley 1, examples of which are described below.

The method comprises at least the following steps a), b), c), e) and f). Step a) consists of manufacturing the hub 10. Step b) consists of manufacturing the ring 20 provided with the rim 22, the outer peripheral track 24 and a first part of the coupling means 60 with the annular insert 40, namely the openings 27 and their edges 28. The step c) consists in producing the annular insert 40 having a second portion of the coupling means 60 to the ring 20, namely the tabs 43 and the riders 44. Step e) consists of joining, in rotation about the axis X1, the annular insert 40 to the hub 10. The step f) consists in securing the annular insert 40 to the ring gear 20 in a coupled configuration, by adjustment of the coupling means 60. The steps a), b) and c) are performed before step e), itself performed before step f). Steps a), b) and c) can be performed simultaneously or successively, in any order. Other intermediate or subsequent steps consist of cooperating the constituent elements of the pulley 1 with the shaft A, the bearing 50 and the belt C.

In the case where the pulley 1 comprises the antivibration ring 30 or any other elastically deformable member interposed between the annular insert 40 and the hub 10, the method has certain differences with that described above. In step a), the hub 10 includes an outer surface 14 adapted to receive the ring 30. The method also comprises a step d) of manufacturing the ring 30. The step e) comprises the following substeps e1) and e2). The substep e1) consists in joining the ring 30 to the outer surface 14 of the hub 10. The substep e2) consists in securing the ring 30 to the annular insert 40. Steps a), b), c) and d) can be performed simultaneously or successively, in any order. The substeps e1) and e2) can also be performed simultaneously or successively, in any order, depending on the means used to ensure the rigid connection between the ring 30, the hub 10 and the insert 40.

The invention also relates to a method of disassembly of the pulley 1, manufactured according to the method above. This disassembly process comprises a step g) comprising separating the annular insert 40 from the ring gear 20 at the coupling means 60, from the coupled configuration to the uncoupled configuration, by pulling on the annular insert 40 in a generally axial direction opposite to the ring gear 20.

Other embodiments of the invention are described below, with reference to FIGS. 8 to 19.

In these embodiments, certain constituent elements of the pulley 1 are identical to those of the first embodiment described above and, for the sake of simplification, bear the same numerical references. Other elements constituting the pulley 1 have a similar operation, but a different structure, in comparison with the first embodiment and have the same numerical references increased by 100 for the second mode, 200 for the third mode, 300 for the second embodiment. fourth mode, 400 for the fifth mode and 500 for the sixth mode. The method of manufacturing the pulley 1, described above, is valid for all embodiments.

Figures 8 to 10 show coupling means 160 belonging to a second embodiment of a pulley 1 according to the invention.

In this second mode, the pulley 1 comprises a ring 120 and an insert 140 incorporating the means 160. The ring 120 includes a radial rim 122, in which are formed three openings 127 through axially, distributed at 120 ° around the axis X1 . Each opening 127 has two lateral inner edges 128, substantially parallel to each other on either side of a radial plane comprising the central axis X1. The insert 140 comprises a U-shaped rider 144 disposed at the end of each of the three curved tabs 43. The rider 144 comprises a base 45 and flexible tabs 146, which can be inserted into the opening 127, in support against the edges 128. The flexible tabs 146 have a greater spacing in the uncoupled configuration to the spacing they have, after deformation against the edges 128, in the coupled configuration of the means 160. Thus, the openings 127, the edges 128 the tabs 43 and the jumpers 144 constitute means 160 for reversible mechanical coupling of the insert 140 and the ring 120.

Figures 11 and 12 show coupling means 260 belonging to a third embodiment of a pulley 1 according to the invention.

In this third embodiment, the crown 120 is similar to that of the second embodiment and is provided with openings 127 having internal edges 128. The pulley 1 comprises an insert 240, provided with three curved legs 243 and three jumpers 244. Each Jumper 244 has a C shape slightly different from the shape of jumpers 44 and 144, but its operation is similar.

The main difference with the previous embodiments is that tabs 243 are thinner than tabs 43 in orthoradial direction, i.e., perpendicular to a radial plane comprising the central axis X1. The tabs 243 thus have a lower mechanical strength to the tabs 43, nevertheless sufficient under the normal operating conditions of the pulley 1, without malfunction. On the other hand, these tabs 243 form a brittle or fusible part in coupled configuration, when the pulley 1 is subjected to an over torque exceeding a predetermined threshold torque. The breaking or merging of the different parts 243 brings the ring 120 and the annular insert 240 in uncoupled configuration, while the pulley 1 is in operation with a rotational movement M1. No component of the pulley 1 separates from the other elements: the ring 120 driven by the belt C pivots freely on the bearing 50, while the insert 240 remains connected to the ring 30, the hub 10 and the shaft A. The transmission of torque and movement M1 of the belt C to the shaft A is no longer ensured, so that the compressor stops.

Thus, the openings 127, the edges 128, the tabs 243 and the jumpers 244 constitute means 260 for reversible mechanical coupling of the insert 240 and the ring 120, among which the parts 243 constitute irreversible decoupling means. After breaking or melting of the parts 243, the insert 240 must be replaced, but the other constituent elements of the pulley 1 are preserved.

Alternatively, the means 260 or the pulley 1 may include one or more brittle or fusible parts in case of over-torque, which are located at a different location, for example on the tabs of the jumpers 244, or on the hub 10.

Figures 13 to 15 show coupling means 360 belonging to a fourth embodiment of a pulley 1 according to the invention.

In this fourth mode, the pulley 1 comprises a ring gear 320 and an insert 340 incorporating the means 360. The ring gear 320 includes a radial rim 322, in which are formed three openings 327 axially through, distributed at 120 ° around the axis X1 . Each opening 327 has two lateral inner edges 328, facing each other on either side of a radial plane comprising the central axis X1. Each opening 327 is slightly oblong in the radial direction. In other words, the distance between the lateral edges 328 in an orthoradial direction is less than the distance between the inner and outer edges in a radial direction. The insert 340 comprises a pin 344 disposed at the end of each of the three curved tabs 43. The pin 344 comprises a base 345 and a cylindrical portion 346 centered on an axis parallel to the central axis X1. When the pins 344 are introduced in an axial direction in the openings 327, the means 360 allow a radial clearance due to the oblong shape of the openings 327, and an axial play due to the slightly flexible nature of the tabs 43. However , a tight fit is preferably provided between the cylindrical portions 346 and the side edges 328, so as to exclude any orthoradial clearance between the pins 344 and the openings 327. Alternatively or in addition to this tight fit, the means 360 may include an angular offset between at least one of the pins 344 and the opening 327 receiving the pin 344, when the other pins 344 are positioned in the other openings 327 in coupled configuration. This angular offset involves a slight twist of the tab 43 to introduce the pin 344 in the opening 327 offset, but reinforces the rotational connection in the coupled configuration. Thus, the openings 327, the edges 328, the tabs 43 and the pins 344 constitute means 360 of reversible mechanical coupling of the insert 140 and the crown 120. These means 360 exclude any rotational play around the central axis X1 between the ring 20 and the annular insert 40.

Figures 16 to 18 show coupling means 460 belonging to a fifth embodiment of a pulley 1 according to the invention.

In this fifth mode, the pulley 1 comprises a ring 420 and an insert 440 incorporating the means 460. The ring 420 includes a radial rim 422 lacking openings, and an outer portion 423 including three grooves 427 distributed at 120 ° around of the X1 axis. More specifically, the grooves 427 open on the inner face and the front side of the portion 423. Each groove 427 has two lateral inner edges 428, substantially parallel to each other on either side of a radial plane comprising the central axis X1. The insert 440 comprises three curved legs 43 and, at the end of each of them, a lug 444 which extends radially to the axis X1. Each lug 444 can be inserted into one of the grooves 427, being fitted against the edges 428, to move from the coupled configuration to the disengaged configuration. Thus, the grooves 427, the edges 428, the tabs 43 and the lugs 444 constitute reversible mechanical coupling means 460 of the insert 440 and the ring 420.

In FIG. 19 are shown coupling means 560 belonging to a sixth embodiment of a pulley 1 according to the invention.

In this sixth mode, the pulley 1 comprises the ring 420 and an insert 540 incorporating the means 560. The ring 420 is similar to that of the fifth embodiment and is provided with three grooves 427 distributed at 120 ° around the axis X1 , which open on the inner face and the front side of the part 423. The main differences with the previous embodiments relate to the insert 540 and the means 560. The insert 540 comprises an annular portion 540a delimiting the inner cylindrical surface 41, and a curved portion 543 which extends axially towards the rearward and radially outwardly from a rear side 542 of the annular portion 540a. Parts 540a and 543 have a generally annular shape centered on the axis X1. The insert 540 also comprises a member 546 initially secured to the portion 543. The member 546 comprises lugs 544 connected to a radial annular disk 545 centered on the axis X1. More specifically, the member 564 comprises three lugs 544 which are distributed at 120 ° around the axis X1 and extend radially to the axis X1 outwardly from the outer periphery of the disk 545.

Initially; a rear face of the portion 543 and a front face of the disk 545 are secured at a connecting portion 548, so that the insert 540 forms a one-piece assembly at the portion 543 and the member 546. Part 548 is schematically represented by a radial line between portion 543 and member 546 in FIG. 19. By way of example, portion 548 includes a welding seam, dots or other means of binding adapted to the present application, as described below. The part 548 at least partly around X1 tax, preferably all around the axis X1. The link 548 is such that the disc 545 and the lugs 544 belong to the insert 540 when it is mounted in the pulley 1. Each lug 544 can be inserted into one of the grooves 427, while being fitted against the edges 428, as in the fifth embodiment, so as to go from the coupled configuration to the uncoupled configuration.

In practice, the link 548 has sufficient mechanical strength under the normal operating conditions of the pulley 1, without malfunction, to maintain the monobloc insert 540, with the portion 543 and the member 546 which are integral. On the other hand, this connecting part 548 forms a brittle or fusible part in coupled configuration, when the pulley 1 is subjected to an overtorque exceeding a predetermined threshold torque. The breaking or melting of the connecting portion 548 brings the crown 420 and the annular insert 540 uncoupled configuration, while the pulley 1 is in operation with a rotational movement M1. No component of the pulley 1 separates from the other elements: the crown 420 driven by the belt C pivots freely on the bearing 50, while the insert 540 remains connected to the ring 30, the hub 10 and the shaft A. The transmission of torque and movement M1 of the belt C to the shaft A is no longer ensured, so that the compressor stops. Advantageously, in the sixth embodiment, the member 546 is enclosed between the insert 540 and the 420, so that this body 546 can not be ejected from the rotating assembly and therefore causes no discomfort outside the pulley 1.

Thus, the grooves 427, the edges 428, the lugs 543, the lugs 544 and the disk 545 forming the member 546, as well as the connecting portion 548 constitute means 560 for reversible mechanical coupling of the insert 540 and the the ring 420, among which the connecting portion 548 constitutes irreversible disengagement means. After rupture or melting of the connection 548, the insert 540 and the member 546 can be secured again, preferably by welding, while the other constituent elements of the pulley 1 are preserved.

As a variant not shown, the means 60, 160, 260, 460 or 560 may include an angular offset comparable to that of the means 360, so as to exclude any rotational play around the central axis X1 between the ring and the insert.

In Figures 1 to 19, the pulley 1 is shown in coupled configuration. Whatever the embodiment, the means 60, the ring 20 and the insert 40 are adjustable between a coupled configuration where the insert 40 is integral with the ring 20 in rotation M1 about the axis X1 but free in rotation relative to the ring 20 about the axis X1, and a disengaged configuration where the insert 40 is separable from the ring 20.

The means 60 comprise at least one member 44 integral with the insert 40 or the ring gear 20 and at least one orifice 27 formed in the ring 20 or in the insert 40, adjustable from the uncoupled configuration to the coupled configuration by mechanical cooperation , in particular by clipping. This cooperation can be achieved by manual action, without requiring special tools. The member 44 and the corresponding orifice 27 may extend in a substantially radial or essentially axial direction. Preferably, the means 60 include several male members 44 and several female orifices 27 distributed around the axis X1, each orifice 27 being adapted, in coupled configuration, to receive at least partially one of the members 44. Preferably also, the coupling means 60 are entirely mechanical, and not electromagnetic or frictional.

Furthermore, the pulley 1 may be shaped differently from the figures without departing from the scope of the invention. In particular, the coupling means 60, 160, 260, 360, 460 or 560 may be shaped differently from Figures 1 to 19 without departing from the scope of the invention.

In variant not shown, the antivibration ring 30 may be replaced by an elastically deformable member adapted to the present application, positioned between the insert 40 and the outer surface 14 of the hub 10. Preferably, this member is positioned directly in contact with the insert 40 and the outer surface 14 of the hub 10. Still preferably, this member is secured to the insert 40 and the hub 10, as described above for the ring 30. Still preferably, this member comprises at least one deformable portion in the axial direction between the hub 10 and the annular insert 40. According to a particular example, this member may comprise an axial compression spring. According to another particular example, this compression spring may be constituted by one or more Belleville washers.

According to another variant not shown, for some particular applications, the pulley 1 may be devoid of antivibration ring 30.

In addition, the technical features of the various embodiments may be, in whole or in part, combined with each other. Thus, the pulley can be adapted, in terms of cost, functionality and performance, for different applications.

Claims

Transmission pulley (1) for an automobile accessory, in particular for an air-conditioning compressor, this pulley (1) comprising:

- A hub (10) centered on a central axis (X1) and adapted to be secured to a shaft (A) belonging to the automobile accessory,

- a ring gear (20; 120; 320; 420) comprising a rim (22; 122; 322; 422) which extends radially to the central axis (X1) and an outer peripheral race (24) for rotational driving (M1) of the ring gear (20; 120; 320; 420) by a belt (C),

an annular insert (40; 140; 240; 340; 440; 540) secured in rotation with the hub (10), and

means (60; 160; 260; 360; 460; 560) for coupling the annular insert (40; 140; 240; 340; 440; 540) to the ring gear (20; 120; 320; 420),

characterized in that the coupling means (60; 160; 260; 360; 460; 560) are distributed on the one hand (27,28; 127,128; 327,328; 427,428) on the ring (20; 120; 320; 420) and secondly (43,44; 43,144; 243,244; 43,344; 43,444; 543,546,548) to the annular insert ( 40, 140, 240, 340, 440, 540), and are adjustable between:

a coupled configuration in which the annular insert (40; 140; 240; 340; 440; 540) is integral with the rotating ring (20; 120; 320; 420) around the central axis (X1); and free in translation relative to the ring gear (20; 120; 320; 420) along the central axis (X1), the coupling means (60; 160; 260; 360; 460; 560) allowing a clearance axial parallel to the central axis (X1) between Ea ring (20; 120; 320; 420) and the annular insert (40; 140; 240; 340; 440; 540), and

an uncoupled configuration where the annular insert (40; 140; 240; 340; 440;

540) is separable from the ring gear (20; 120; 320; 420).

Pulley (1) according to claim 1, characterized in that it also comprises an elastically deformable member (30) positioned around the central axis! (X1) between the annular insert (40; 140; 240; 340; 440; 540) and an outer surface (14) of the hub (10).

3. Pulley (1) according to one of the preceding claims, characterized in that in the coupled configuration, the coupling means (60; 160; 260; 360; 460; 560) exclude any rotating play around the axis central (X1) between the ring gear (20; 120; 320; 420) and the annular insert (40; 140; 240; 340; 440; 540).

4. Pulley (1) according to one of the preceding claims, characterized in that the coupling means (60; 160; 260; 360; 460; 560) comprise flexible tabs (43; 243; 543) according to a radial direction to the central axis (X1) and in axial direction to the central axis (X1), to the assembly and when the pulley (1) is in use.

5. Pulley (1) according to one of the preceding claims, characterized in that the coupling means (60; 160; 260; 360; 460; 560) are adjustable without screwing between the coupled configuration and the uncoupled configuration.

6. Pulley (1) according to one of the preceding claims, characterized in that the coupling means (60; 160; 260; 360; 460; 560) are adjustable from the coupled configuration to the uncoupled configuration by pulling on the annular insert (40; 140; 240; 340; 440; 540) in a generally axial direction opposite to the ring gear (20; 120; 320; 420), in particular without the use of a specific tool.

7. Pulley (1) according to one of the preceding claims, characterized in that the coupling means (260; 560) comprise at least one part (243; 548) which, in coupled configuration, is plastically deformable, brittle or fuse when the pulley (1) is subjected to an overtorque exceeding a predetermined threshold torque, the plastic deformation, rupture or melting of this part (243; 548) bringing the ring (120) and the annular insert (240) into uncoupled configuration.

8. Pulley (1) according to one of the preceding claims, characterized in that the coupling means (60; 160; 260; 360; 460; 560) comprise at least one member (44; 144; 244; 344; 444; 544) integral with the annular insert (40; 140; 240; 340; 440; 540) or the ring gear (20; 120; 320; 140) and at least one orifice (27; 127; 327; formed in the ring gear (20; 120; 320; 420) or in the annular insert (40; 140; 240; 340; 440; 540), adjustable in the configuration disconnected to the configuration coupled by mechanical cooperation, in particular by clipping.

9. Pulley (1) according to one of the preceding claims, characterized in that the coupling means (60; 60; 260; 360; 460; 560) comprise:

at least one member (44; 144; 244; 344; 444; 544) extending radially and / or axially to the central axis (X1) from a portion (42,43; 42,243) of ring (40; 140; 240; 340; 440; 540), and

at least one orifice (27; 127; 327; 427) formed in the ring (20; 120;

320; 420) in a substantially radial or essentially axial direction relative to the central axis (X1), preferably a plurality of orifices (27; 127; 327; 427) distributed about the central axis (X1), the orifice or each port (27; 127; 327; 427) being adapted, in coupled configuration, to receive at least partially the member or one of the members (44; 144; 244; 344; 444; 544) belonging to the annular insert; (40; 140; 240; 340; 440; 540).

10. Pulley (1) according to one of the preceding claims, characterized in that the coupling means (60; 160; 260; 360; 460; 560) comprise an elastically deformable jumper (44; 144; 244), a axial pin (344) and / or a radial pin (444; 544).

11. Pulley (1) according to one of the preceding claims, characterized in that the coupling means (360) comprise orifices (327) distributed in the ring (320) about the central axis (X1) and suitable to receive members (344) integral with the annular insert (340), and in that an angular offset is provided between at least one of the members (344) and the orifice (327) receiving this member when the other members are positioned in the other orifices in mated configuration, this angular offset excluding any rotational play around the central axis (X1) between the ring gear (320) and the annular insert (340) in the coupled configuration.

12. A method of manufacturing a pulley (1) according to one of claims 1 to 11, characterized in that it comprises at least steps consisting of:

a) manufacturing the hub (10);

b) manufacturing the ring gear (20; 120; 320; 420) provided with the rim (22), the outer peripheral track (24) and a first portion (27,28; 127,128; 327,328; 427, 428) coupling means (60; 160; 260; 360; 460; 560) to the annular insert (40; 140; 240; 340; 440; 540);

c) manufacturing the annular insert (40; 140; 240; 340; 440; 540) having a second portion (43,44; 43,144; 243,244; 43,344; 43,444; 543,544,545; 546, 547, 548) coupling means (60; 160; 260; 360; 460,560) to the ring gear (20; 120; 320; 420);

e) securing in rotation about the central axis (X1) the annular insert (40; 140;

240; 340; 440; 540) to the hub (10); and

f) securing the annular insert (40; 140; 240; 340; 440,540) to the ring gear (20;

120; 320; 420) in coupled configuration by adjusting the coupling means (60; 160; 260; 360; 460,560);

steps a), b) and c) being performed before step e), which is performed before step f).

13. A method of manufacturing a pulley (1) according to claim 12, characterized in that in step a), the hub (10) includes an outer surface (14) adapted to receive an elastically deformable member (30). ; in that the method also comprises a step d) of manufacturing the elastically deformable member (30); and in that step e) comprises the following substeps e1) and e2) consisting of:

e1) positioning the elastically deformable member (30) against the outer surface (14) of the hub (10); and

e2) positioning the elastically deformable member (30) against the annular insert (40;

140; 240; 340; 440, 540). 14. A method of disassembling a pulley (1) made by implementing the manufacturing method according to one of claims 12 or 13, characterized in that the disassembly process comprises a step g) of separating the insert ring (40; 140; 240; 340; 440; 540) of the ring gear (20; 120; 320; 420) at the coupling means (60; 160; 260; 360; 460; 560) from the configuration coupled to the uncoupled configuration by pulling on the annular insert (40;

140; 240; 340; 440; 540) in a generally axial direction opposite to the ring gear (20; 120; 320; 420).