EP1669592A1 - Starter apparatus for an internal combustion engine - Google Patents

Abstract

The device has a front planetary speed reducer (19) rotatively connecting a pulley (80) to an armature shaft (14) driven by an electric motor (16). The reducer has planet gears (36) driving a sun gear (52), a planet carrier (40) on which the gears (36) are mounted and a ring gear (44) with teeth to drive the gears (36). The ring gear is housed in an inner bore (84) of the pulley and the carrier is fixed relative to a case (48).

Description

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a starting device, also called a starter, for driving a heat engine, also called an internal combustion engine, in particular a motor vehicle, via at least one belt as described in FIG. French Patent Application No. 0350376 filed July 28, 2003, published on February 4, 2005 under the number FR 2 858 366 and shown in Figures 1a and 1b appended hereto.

STATE OF THE ART

The starting device 10 comprises an output shaft 12 or drive shaft which is intended to be rotated by the armature shaft 14 of an electric motor 16 when the latter is electrically powered, here by the intermediate of two reducers epicyclic gear before 19, also called first reducer, and rear 18, also called second reducer, cascaded or series, that is to say that their reduction rate is increasing.

The output shaft 12 and the armature shaft 14 are coaxial axis X1.

The rear free end 20 of the output shaft 12 is guided in rotation by a rear bearing 24, with the interposition of a rear guide sleeve 25.

A movable assembly 28 includes a rear freewheel 30 which drives a front gear 32. The movable assembly 28 is mounted to slide axially on a splined intermediate section 34 of the output shaft 12 so as to be integral with the latter in rotation.

FIG. 1b shows that the front epicyclic gear reducer 19 comprises a set of satellites 36 whose axes of rotation 38 are carried by a flange 40 of transverse orientation, ie perpendicular to the axis X1, which is integral in translation and in rotation with the rear free end 20 of the output shaft and which is fixed on the latter by crimping.

The satellites 36 are immobilized axially in translation by a plate 42 force-fitted on the axes 38 of the satellites 36.

The gearbox 19 also comprises a ring gear 44, which is made in one piece with an outer axial annular skirt 33 fixed in the casing or housing 48 of the starter 10. This ring 44 has a bottom (not referenced) ) in the form of a flange of transversely oriented transverse orientation for passage of the shaft 12. The sleeve 25 is between the outer periphery of the shaft 12 and the inner periphery of the flange of the ring 44.

The satellites 36 mesh with splines 50 carried by a front section 52 of the output shaft 13 of the epicyclic gear train of the rear gearbox 18.

The free end 59 before the output shaft 13 of the rear gear 18 is guided in rotation in a blind axial bore 57 which is formed in the rear face of the rear free end 20 of the drive shaft with interposition a guide sleeve 63. The free end 59 before the shaft 13 is wedged in translation forward by a wedging ball 60 which is housed in the bottom of the blind axial bore 57.

The rear epicyclic gearbox 18 is similar to the front gear 19 and comprises a set of satellites 37 whose axes of rotation 39 are carried by a flange 41 of transverse orientation, which is integral in translation and in rotation with the shaft 13 movement output and which is fixed on the latter by crimping.

The satellites 37 are immobilized axially in translation by a plate 43 force-fitted on the axes 39 of the satellites 37.

The gearbox 18 also comprises a ring gear 45 which is made in one piece with an external axial annular skirt 31 fixed in the casing or housing 48 of the starter 10. This ring has a cross-shaped perforated flange bottom with radial interposition a guide sleeve between the inner periphery of the transverse flange of the ring 45 and the outer periphery of the shaft 13.

The satellites 37 mesh with splines 51 carried by a front section 53 of the armature shaft 14.

The free end 54 before the armature shaft 14 is guided in rotation in a blind axial bore 56 which is formed in the rear face of the rear free end of the output shaft 13 with the interposition of a socket The free end 54 of the armature shaft 14 is translationally wedged forward by a wedging ball 61 which is housed in the bottom of the blind axial bore 56.

The starter 10 also comprises an electromagnetic contactor 62 (FIG. 1a), of general design known in the field of motor vehicle starters, provided with a movable magnetic core 64 whose displacements are caused by a coaxial annular winding or winding 65. also called solenoid, of axis X2 parallel to the axis X1. This core controls the axial displacement of the moving element 28 by means of a lever 66 which is pivotally mounted about an intermediate axis Y orthogonal to the axes X1 and X2.

The movable core 64 acts on the upper end 68 of the lever 66, as it moves rearwardly driven by the solenoid 65, so as to cause a corresponding axial displacement from behind. before the lower end 70 of the lever which is here shaped fork to act on the moving element 28.

The contactor 62 is supplied with electric current to cause both the axial displacement of the moving element 28 forward and the starting of the electric motor 16 by means of a movable contact (not referenced) actuated by the mobile core 64.

The electric motor 16, when electrically powered via the movable contact of the contactor, rotates the armature shaft 14. The latter transmits this rotational movement to the output shaft 12 via the two consecutive reducers 18 and 19.

For more details on the contactor we refer for example to the document FR A 2,795,884, which describes in particular the movable contact, the spring teeth against teeth, the return spring and the fixed core of the contactor.

The casing or housing 48 houses, with the exception of a portion of the contactor 62, all the components of the starter which, for the drive of an internal combustion engine, also called a heat engine (not shown), comprises a pulley groove 80 which is arranged outside the housing 48, and which is coaxial axis X1 with the drive shaft 12 whose free end 22 is guided in rotation by the pulley 80 with the interposition of a bearing ball bearing 82 arranged inside the axial bore 84 which passes through the tubular body 86 of the pulley 80, the front portion of which is grooved externally 88 to receive a belt 89.

The rear portion 90 of the body 86 of the pulley 80 is of reduced diameter and is rotatably mounted in the housing or housing 48 through a rear ball bearing 92 which is received in a concave housing 94 formed in a housing. tubular open front end 96 of the casing or casing 48.

The design of the pulley 80 and bearings 82 and 92 is such that the pulley 80 is fixed axially relative to the housing 48 along the axis X1.

The starter 10 thus comprises, from rear to front, an axial stack, of axis X1, consisting of the electric motor 16 with its armature shaft 14, the two consecutive reducers 18 and 19, the moving element 28 with freewheeling 30 and the movement output pulley 80.

The forward axial displacements of the moving element 28 with its front pinion 32 are limited by a forward axial abutment 110, which is here a rod mounted on the shaft 12 by an elastic ring 112 mounted in a groove 116 of the tree 12.

To constitute a controlled coupling mechanism in rotation, or clutch, with the pinion gear 32, the rear portion 90 of the inner bore 84 of the axially fixed pulley 80 is toothed internally with a group of teeth to form a ring gear internally. 118 in which the pinion 32 with its complementary teeth 120 can penetrate axially from rear to front under the action of the force applied to the moving element 28 by the fork 70.

Thanks to the coupling mechanism 32-118, it is possible to separate the pulley 80 in rotation from the free wheel 30 and therefore from the drive shaft 12 which therefore does not operate continuously for very long periods of operation and in a very restrictive environment such as that of a heat engine.

The freewheel 30 is of known general structure with cylindrical rollers 29 of the type commonly used in sprocket starters whose performance, qualities and reliability are well known and adapted to the automotive context. In addition, such a wheel is of reduced cost and requires only reduced lubrication.

The pinion 32 of movement output of the freewheel, which constitutes the movement input element of the controlled coupling mechanism, has teeth 120 projecting radially outwardly distributed angularly in a regular manner.

The teeth 119 of the ring gear of the pulley 80 are complementary to the teeth 120, and they can all be chamfered at their axial ends to facilitate the axial insertion of the pinion 32 in the ring 118, that is to say the interconnection of the freewheel 30 and pulley 80.

When the supply of the linear actuator constituted by the switch 62 is cut off, the return spring 67 of the movable core 64 recalls the moving element 28, via the lever 66, axially towards the rear.

When the heat engine is started, the pulley 80 is permanently rotated at a speed of between 2,000 and 18,000 revolutions / minute, which is a function of the rotational speed of the engine, and of the drive ratio between the crankshaft pulley and the pulley. 80 of the starter 10.

When the coupling clutch 32, 118 is disengaged, only the pulley 80 and the bearings 82 and 92 rotate continuously. The other coaxial components of the starter 10 are not rotated.

The electric motor 16 comprises a stator 161, a rotor 162 provided with a pack of notched heads receiving the winding 163, a collector 164 with electrically conductive blades 165 connected to the winding 163, and brushes 166 held in contact with the blades 165 by elastic recall organs.

Note also that the housing 48 is divided into a front portion 481 and a rear portion 482 secured by tie rods 483, the skirts 31 and 33 and the stator 161 being axially stacked and held pressed against each other between the front parts and rear 481 and 482.

The skirts 31 and 33 have at their outer periphery indentations (not referenced) for complementary passage of the tie rods 483 so that they are immobilized in rotation by the tie rods 483 of the housing 48, which carries the switch 62 extending over the electric motor.

The rear portion 482 constitutes a guide bearing for a rear free end portion 141 of the armature shaft 14.

Starter devices of this type are axially long.

This length is due to the presence of the moving element 28, and the need to provide an axial clearance sufficient to allow the pinion 32 to disengage completely from the ring gear 118.

OBJECT OF THE INVENTION

In this context, the present invention aims to overcome the defects mentioned above.

This objective is achieved by a starting device for driving a motor vehicle engine by means of at least one pulley, this device comprising a housing, an electric motor, an armature shaft intended to be rotated by the electric motor, and at least one first epicyclic gearbox for rotatably connecting the pulley to the armature shaft, the gearbox comprising a plurality of planet gears, a planet carrier on which the planet gears are mounted free in rotation, and a ring provided with an internal toothing meshing with the planet gears and integral with the pulley, the satellite carrier being fixed relative to the housing.

• La couronne peut être logée dans un alésage interne de la poulie.
• Le dispositif peut comprendre un arbre fixe rigidement fixé sur le carter et s'étendant dans l'alésage, le porte satellites étant solidaire de l'arbre fixe.
• La poulie peut être montée folle autour de l'axe fixe.
• Le dispositif peut comprendre un second réducteur de vitesse monté en série avec le premier réducteur de vitesse.
• Le second réducteur de vitesse peut comprendre un second pignon solaire entraîné en rotation par l'arbre d'induit, plusieurs seconds pignons satellites engrenant le second pignon solaire, un second porte satellites sur lequel les seconds pignons satellites sont montés libres en rotation, une seconde couronne pourvue d'une denture interne engrenant les seconds pignons satellites, et un arbre de sortie de mouvement solidaire du second porte satellites et entraînant le pignon solaire du premier réducteur.
• L'arbre de sortie de mouvement du réducteur peut comprendre un prolongement axial engagé à rotation dans un alésage borgne axial de l'arbre fixe.
• L'arbre d'induit peut être accouplé en permanence à la poulie.

The starter device of the invention may also have in combination one or more of the following features.

• The crown can be housed in an internal bore of the pulley.
• The device may comprise a fixed shaft rigidly fixed to the housing and extending into the bore, the satellite carrier being integral with the fixed shaft.
• The pulley can be mounted idly around the fixed axis.
• The device may include a second speed reducer mounted in series with the first speed reducer.
• The second speed reducer may comprise a second sun gear driven in rotation by the armature shaft, a plurality of second planet gears meshing with the second sun gear, a second planet carrier on which the second planet gears are mounted free to rotate, a second crown provided with an internal toothing meshing the second planet gears, and a motion output shaft secured to the second planet carrier and driving the sun gear of the first gearbox.
• The output shaft of the gearbox may comprise an axial extension engaged in rotation in an axial blind bore of the fixed shaft.
• The armature shaft can be permanently coupled to the pulley.

BRIEF DESCRIPTION OF THE DRAWINGS

• la figure 1a est une vue en coupe axiale d'un dispositif de démarrage selon l'art antérieur,
• La figure 1b est une vue agrandie d'une partie de la figure la, et
• la figure 2 est une vue en coupe axiale d'un dispositif de démarrage conforme à l'invention.

Other characteristics and advantages of the invention will emerge clearly from the description which is given below, by way of indication and in no way limiting, with reference to the appended figures, among which:

• FIG. 1a is an axial sectional view of a starting device according to the prior art,
• Figure 1b is an enlarged view of a portion of Figure la, and
• Figure 2 is an axial sectional view of a starter device according to the invention.

DESCRIPTION OF EXAMPLES OF EMBODIMENT OF THE INVENTION

In the following description, reference is made to a front-to-back orientation, corresponding to the left-to-right orientation in FIGS. 1a / b and 2.

Only the differences between the invention and the prior art will be described below.

The same reference numerals as those used in the description of the prior art for designating identical parts or of the same function will be used to describe the invention illustrated in FIG.

The starting device shown in Figure 2 comprises a housing 48, an electric motor 16, an armature shaft 14 rotated by the electric motor 16 when the latter is electrically powered, and first and second gearboxes to epicycloidal train 19 and 18 rotatingly linking the pulley 80 to the armature shaft 14. This pulley 80 has at its outer periphery a plurality of circumferential grooves 88 to receive in a complementary manner the belt 89.

The first and second epicyclic gearboxes 19 and 18 are referred to as front and rear gearboxes respectively. The first front gearbox 19 comprises a sun gear 52 rotated by the armature shaft 14, a plurality of planet gears 36 meshing with the sun gear 52, a planet gate 40, here in the form of a flange, on which the planet gears 36 are mounted free in rotation, and a crown 44 provided with an internal toothing meshing with the planet gears 36.

The axes of rotation 38 of the satellites 36 are carried by the flange 40. These satellites are immobilized in translation by a plate force-fitted on the axes 38.

The sun gear 52 is constituted by the splined front section 50 of the output shaft 13 of the rear gearbox 18.

According to a characteristic of the invention, the ring gear 44 is integral with the pulley 80, the satellite gate 40 being fixed with respect to the casing 48. In FIG. 2 the ring gear 44 is in one piece with the pulley 80 and extends the backwards.

The output of the front gear 19 is therefore constituted by the pulley 80.

More specifically, the ring 44 is housed in the annular internal bore 84 of the pulley 80. This bore 84 passes through the body of the pulley and is divided into a circular chamber 841 before relatively smaller diameter, and a rear circular chamber 842 of relatively larger diameter, communicating with the front chamber. The ring 44 is housed in the rear chamber 842, the teeth of the ring 44 defining the chamber 842. The two chambers 841 and 842 have axes X1.

The ring 44 is constituted by a plurality of teeth formed on the outer radial wall of the rear chamber 842. These teeth extend axially and are evenly distributed around said outer radial wall.

The satellite gate 40, the satellites 36, the plate 42 and the sun gear 52 are all arranged in the rear chamber 842, inside the ring 44.

In a variant, this rear chamber and therefore the ring gear 44 are attached to the pulley 80, for example by means of screws or by welding. Thus as a variant crown 44 is reduced to a simple annular skirt axially oriented and toothed internally. This skirt, preferably moldable plastic to reduce noise and is reported using screws, preferably distributed circularly in a regular manner, on the rear end of the pulley. Preferably, a thermosetting plastic material is chosen, advantageously reinforced by fibers.

Alternatively the ring 44 has a transverse orientation flange with holes for fixing the ring gear on the pulley 80 by means of fasteners, such as screws. This rim is of course centrally perforated, especially for passage of a fixed shaft 21 described below.

Note that it is the pulley 80 itself which constitutes the bottom of the ring 44 and that one takes advantage of the bearing or bearings 82 described hereinafter of it so that one saves the sleeve 25 of Figure 1b.

The device further comprises a fixed shaft 21 rigidly fixed to the housing 48 and extending into the front chamber 841 of the bore 84, the planet carrier 40 being secured, here by crimping, with a rear end of the shaft fixed 21.

The fixed shaft 21 has in the embodiment shown a threaded front end portion 211 projecting out of the bore 84 forward and received in a threaded hole 202 of a hollow nose 204 which is part of a radial extension 206 before the front portion 481 of the housing 48.

This shaft 211 can be screwed from the inside.

As a variant, this shaft is screwed from the outside, the threaded end comprising, as a variant, at its front face, an impression for a screwing tool of the shaft 21.

Other modes of attachment are possible for example using complementary frustoconical shapes of the hole 202 and the shaft 21 threaded at its free end to receive a nut bearing on the nose 204 via a bearing washer.

This nose 204 is configured to house the pulley 80 therein and has an opening for passage of the belt 89.

Here the nose 204 of an annular shape has a bottom belonging to the front portion 481 of the casing provided with tapped holes for screwing the tie rods 483. This bottom is extended at its end before the extension before 206 of radial orientation, it is that is to say transverse orientation with respect to the axis X1.

This bottom is extended at its rear end by a rearward extension (not referenced) of radial orientation, that is to say of transverse orientation relative to the axis X1.

The rear extension is provided with a circular opening (not referenced) into which the rear end of the pulley 80 and thus the crown 44 penetrates. This rear extension is here longer than the prolongation before 206, the distance between the two extensions depending on the width of the belt 89.

The front portion 481 of the casing is advantageously made of moldable material, here based on aluminum. In a non-visible manner, the rear extension comprises perforated ears for fixing it, for example by means of screws or bolts on a fixed part.

The bearings 82 are housed in the front chamber 841 of the bore 84, and are interposed radially between the fixed shaft 21 and the pulley 80, more precisely the body of the pulley, this pulley 80 being mounted madly around the fixed shaft 21.

Alternatively the two bearings 82 are replaced by a bearing with two rows of balls.

The movement output shaft 13 of the second rear gear 18 has a front end portion 59 of reduced diameter, engaged in a blind hole 57 formed in a rear face of the fixed shaft 21, a guide sleeve 63 being interposed radially between the front portion 54 and the wall of the blind hole 56.

The rear gearbox 18 is of conventional type, with a ring 45 fixed relative to the casing 48, the sun gear 53 being constituted by a fluted front end portion 51 of the armature shaft 14. This reducer comprises as in the 1a and 1b, satellites 37 meshing with the fluted portion 51, a satellite door 41 in the form of a flange secured here by crimping the shaft 13 and a plate 43 force-fitted on the pins 39 carried by the flange 41 for immobilization of the satellites 37, which meshes with the internal teeth of the axial annular skirt 31 of the ring of the second rear gear 18.

This ring is advantageously made of moldable pastic material, preferably thermosetting plastic material, which in one embodiment is reinforced by fibers.

This ring has a bottom (not referenced) flange-shaped transverse orientation relative to the axis X1. This flange is centrally perforated for passage of the shaft 13 with radial interposition of a bearing, such as a guide sleeve, between the inner periphery of the flange of the ring 45 and the outer periphery of the shaft 13. A shoulder exists at the outer periphery of this flange for axial wedging of the ring between a shoulder delimiting at the rear the aforementioned opening of the rear extension of the front portion 481 of the housing and the deformations of a tubular yoke (not referenced) interposed between the front portion 481 and the rear portion 482 of the housing 48 connected to the front portion by the tie rods 483 tightening the cylinder head.

Here the electric motor 16 is of the type described in document EP A 0 749 194 to which reference will be made for further details.

The skirted crown 31 can be immobilized in rotation by means of studs engaged in grooves formed in the edge of the opening of the rear extension as described in the document FR A 2 787 833 to which reference will be made.

The second reducer 18 can therefore be of the standard type.

It will be appreciated that, thanks to the invention, it is possible to use a maximum number of parts of a starter of the standard type because the ring 44 is, according to the invention, integral with the pulley 80.

The solution is therefore economical and furthermore can be bulky axially because the rear part of the pulley can come closest to the second gearbox, the opening of the rear extension of the front part 481 of the casing having a dual function namely penetration of the pulley and axial cage of the crown of the second gear of radial size greater than that of the ring 44.

Of course it depends on the applications. Thus alternatively the crowns of the two reducers 18, 19 may have the same size. To do this simply change the size of the wedging shoulder of the ring gear of the second reducer 18, an axial play existing in all cases between the pulley and this ring.

Finally, note that the starting device also comprises a second driving pulley (not shown) driven in rotation, preferably in a disengageable manner, by the crankshaft of the heat engine, for example with the aid of a second pulley, and connected in rotation to the pulley 80 by the belt 89, and a freewheel (not shown) preferably interposed between the second pulley and the crankshaft, the freewheel for uncoupling the electric motor from the engine thermal when the engine is launched and therefore when the crankshaft has a higher speed of rotation than the second pulley.

The freewheel is for example integrated in the second driving pulley.

The armature shaft 14 is permanently coupled to the pulley 80, which has a reduced size since the freewheel is preferably located outside this pulley.

The starter device described above has many advantages.

It is particularly compact because the first front gear 19 is housed inside the pulley 80.

The free wheel 30 is offset at the crankshaft, which contributes to further shorten the axial length of the device.

Indeed, one can thereby remove the electromagnetic contactor 62, the core 64 and the lever 66, which lighten the device and reduce the axial size. These elements are replaced by a simple contactor, for example mechanical or electronic provided for example with at least one transistor acting as a switch, for controlling the power supply of the motor 16.
In a variant, the electromagnetic contactor (not shown) can be kept simplified, since its movable core no longer has to drive the lever.
There is therefore a greater choice to implement this electromagnetic contactor or the simple contactor. Here this contactor is implanted outside.
Of course we can mount this switch for example on the housing 48 or on the rear portion 483.
The device of the invention makes it possible to obtain a reduction ratio between the armature shaft 14 and the pulley 80 close to that of the prior art.

en notant ωe la vitesse de rotation du pignon solaire, ωs la vitesse de rotation à la sortie du réducteur (vitesse du porte satellite), n1 le nombre de dents du pignon solaire et n3 le nombre de dents de la couronne.For the front and rear reducers of the prior art, it is possible to write: $$\mathrm{\omega }\mathrm{s}=\mathrm{\omega }\mathrm{e}\left(1+\mathrm{not}3/\mathrm{not}1\right)$$

noting lae the speed of rotation of the sun gear, ωs the rotational speed at the gearbox output (speed of the satellite gear), n1 the number of teeth of the sun gear and n3 the number of teeth of the gear.

For a crown of 56 teeth and a pinion of 16 teeth, the reduction ratio is 4.5.

For a crown of 59 teeth and a pinion of 13 teeth, the reduction ratio is 5.54.

If the two reducers 18 and 19 are identical, the device of the prior art makes it possible to obtain a reduction ratio between the armature shaft 14 and the pulley 80 of 20.25 (4.5x4, 5) or , 69 (5.54x5, 54).

For the front reducer 18 of the device of the invention, it is possible to write with the same notations: $$\mathrm{\omega }\mathrm{s}=\mathrm{\omega }\mathrm{e}\left(\mathrm{not}3/\mathrm{not}1\right)$$

In this case, the speed at the outlet of the gearbox corresponds to the speed of the crown, that is to say at the speed of the pulley.

For a crown of 56 teeth and a pinion of 16 teeth, the reduction ratio is 3.5.

For a crown of 59 teeth and a pinion of 13 teeth, the reduction ratio is 4.5.

Assuming that the front and rear gears comprise gears and crowns of the same number of teeth, the reduction ratio between the armature shaft 14 and the pulley 80 is 15.75 (3.5x4.5) or 24. , 93 (4.5x5.54).

The advantages mentioned above are achieved by means of a device consisting of a number of parts considerably reduced compared to the solution of Figures la and 1b.

Finally, it is known that the torques applied on the pulley 80 are very important. The fact of transmitting them directly from the satellites to the pulley makes the device more robust, since the chain torque transmission is shorter and the number of parts subjected to these couples is lower.

Of course, the present invention is not limited to the described embodiments.

Thus alternatively the pulley has at its outer periphery a plurality of axially oriented teeth and the belt also has teeth for cooperating in a complementary manner with the teeth of the pulley.
Alternatively the belt is replaced by a chain cooperating with teeth of the pulley.
Alternatively a shock absorber is provided within the ring gear of at least one of the gearboxes 18, 19. This shock absorber ring belongs in one embodiment to the first gearbox 19. This ring comprises for example an outer portion fixed, in one piece with the pulley or reported above on the pulley, and an inner ring coaxially mounted in the outer ring. This inner ring is provided with the internal toothing meshing with the satellite gears. Elastic members are also provided. These members intervene between the outer part, in a crown-like embodiment, and the inner ring. These members are mounted in housings vis-à-vis made in said crowns.
The elastic members consist of an embodiment made of rubber or elastomer blocks.
In one embodiment, the fixed ring comprises projections directed radially towards the inner ring and the inner ring of the ribs directed radially towards the fixed outer ring, each block being interposed or inserted circumferentially between the radial faces opposite a projection and a rib as visible for example in the document FR 2 829 812. It is also possible to adopt the other arrangements described in this document or those described in document FR 2 514 425.
Of course we can adopt the same provision for the other reducer 18.
In all cases the ring 44 is carried by the pulley and is integral with the pulley. This ring has a fixed part in one piece with the pulley or reported on the pulley.

Claims (17)

Starting device for driving a heat engine, particularly a motor vehicle, via at least one pulley (80), this device comprising a housing (48), an electric motor (16), a shaft armature assembly (14) for rotational driving by the electric motor (16), and at least one first epicyclic gearbox gearbox (19) for rotatably coupling the pulley (80) to the spindle shaft (16). armature (14), the gearbox comprising a plurality of planet gears (36), a planet carrier (40) on which the planet gears (36) are rotatably mounted, and a ring gear (44) provided with internal gear teeth meshing with the gears satellites (36) and integral with the pulley (80), the satellite carrier (40) being fixed relative to the housing (48). Device according to claim 1, characterized in that the ring gear (44) has a fixed part integral with the pulley (80). Device according to claim 2, characterized in that the ring (44) is housed in an internal bore (84) of the pulley (80). Device according to any one of claims 1 to 3, characterized in that the internal bore (84) of the pulley (80) and divided into a front circular chamber (841) and a rear circular chamber (842) of diameter larger communicating with the front chamber (841) and in that the ring gear (44) of the first gear (19) is housed in the rear chamber (842), the teeth of the crown defining the rear chamber (842). Device according to claim 1, characterized in that the ring (44) is attached to the pulley (80). Device according to claim 5, characterized in that the pulley (80) has an internal bore (84), in that the internal bore (84) of the pulley (80) comprises a circular front chamber (841), in that that the teeth of the ring gear (44) of the first gear (19) define a rear circular chamber (842), in that said ring gear (44) is attached to the pulley (80) and that in the rear circular chamber ( 842) is larger in diameter than that of the front chamber (841) communicating with the rear chamber (842). Device according to claim 4 or 6, characterized in that at least one bearing (82) is housed in the front chamber (841). Device according to any one of claims 4, 6 or 7, characterized in that it comprises a fixed shaft (21) rigidly fixed to the housing (48) and extending into the front chamber (841) of the bore internal (84) of the pulley, the satellite carrier (40) being integral with the fixed shaft (21). Device according to claims 7 and 8, characterized in that the pulley (80) is mounted idly about the fixed shaft (21), the bearing (82) being interposed radially between the fixed shaft (21) and the body of the the pulley (82). Device according to claim 8 or 9, characterized in that the first speed reducer (19) comprises a sun gear (52) intended to be rotated by the armature shaft (14), the planet gears (36). meshing with the sun gear (52) integral with an extension (59) of reduced diameter rotatably engaged in an axial blind bore of the fixed shaft (21). Device according to claim 10, characterized in that the satellite carrier (40) the satellites (36) and the sun gear (52) of the first speed reducer (19) are arranged in the rear chamber (842), inside the ring (19) Device according to any one of claims 1 to 11, characterized in that it comprises a second speed reducer (18) connected in series with the first speed reducer (19). Device according to claim 12 taken in combination with the claim, characterized in that the second speed reducer (18) comprises a second sun gear (53) integral with the armature shaft (14), a plurality of second planet gears (37). ) meshing with the second sun gear (53), a second planet carrier (41) on which the second planet gears (37) are rotatably mounted, a second ring gear (45) provided with an internal toothing meshing with the second planet gears ( 36), and a motion output shaft (13) integral with the second planet carrier (41) and driving the sun gear (52) of the first gearbox (19). Device according to claim 13 taken in combination with claim 10 or 11, characterized in that the movement output shaft (13) comprises an axial extension (59) rotatably engaged in an axial blind bore of the fixed shaft ( 21). Device according to any one of claims 1 to 14, characterized in that the armature shaft (14) is permanently coupled to the pulley (80). Device according to any one of claims 1 to 15, characterized in that the ring gear (44) of the first gear (19) is in one piece. Device according to any one of claims 1 to 15, characterized in that the ring gear (44) of the first gearbox (19) is provided with a shock absorber.

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