FR2863015A1 - Motor vehicles starter, has speed reducing gear including ring gear with male stop unit adapted to width of cavity of support for receiving control lever to stop rotation of ring gear - Google Patents

Abstract

The starter has an electric motor coupled to a starter drive assembly with interposition of a speed reducing gear having a ring gear (46). An electromagnetic contactor (32) is intended to supply the motor and to actuate a shifter lever in gear with a driver of the assembly. The ring gear has a male stop unit adapted to width of a cavity (69) of a support (16) receiving a control lever to stop a rotation of the ring gear.

Description

Starter motor vehicle with gearbox equipped with means

  immobilization in rotation of the crown.

  TECHNICAL FIELD OF THE INVENTION The invention relates to a motor vehicle starter comprising: an electric motor driving a launcher in rotation with the interposition of an epicyclic gear reducer comprising a fixed crown with a toothed skirt internally, means for immobilizing rotation of said ring in the support of the starter, and a contactor for supplying the electric motor and operating a control lever engaged with the coach of the launcher.

  State of the art The stop in rotation of a reducing crown is generally achieved by specific shapes distributed at the periphery of the toothed gear of the speed reducer requiring counters forms arranged opposite the fixed support of the starter. The interlocking cooperation of the shapes and counterforms thus makes it possible to obtain means for stopping the rotation of the crown.

  The document FR-A-2787833 described in Figures 2 and 3, a starter of the kind mentioned, wherein the rear support of the control lever of the launcher, comprises a half cylinder maintained by an insert part reported. This support piece generally made of thermoplastic material, is blocked by the contactor tank, and requires a precise housing in the starter support, which is obtained by machining. This solution uses an additional part, which incurs an additional cost, because the bearing faces of the part on the support, and the contactor on the support, must be machined with precision to ensure the stable positioning without play of the part , and the control lever. The rotational stop of the toothed ring of the speed reducer is effected by means of studs molded in a flexible material, for example elastomer material, which are interposed between the ring and complementary portions of the cavity of the support. The placement of these pads requires the formation of grooves in the support.

  These known devices require specific shapes on the support of the starter 1 and on the gearbox crown, which complicate the design of the parts, and increase the costs of molding and machining.

  OBJECT OF THE INVENTION The object of the invention is to provide a starter which overcomes the aforementioned drawbacks, so as to obtain a locking in rotation of the gearbox crown by simplifying the operations of machining the support, and molding of the crown.

  The starter according to the invention is characterized in that the ring gear of the reducer comprises an extension shaped as a male stop element engaged in a cavity of the support receiving the control lever. The extension of the crown adapts to the width of the cavity, which constitutes a female element for positioning and guiding the control lever.

  The design of the starter support is simplified compared to that of the document FR2787833, because it does not require ribs or specific shapes for stopping rotation of the crown. The control lever housing cavity automatically performs this stop function when inserting the crown extension.

  Preferably, the extension of the crown comprises an articulation clevis of the control lever. The crown is also simplified because the pivoting fork of the control lever simultaneously ensures the rotational stop of the crown. A pad of flexible material is interposed between the extension of the ring and a contact surface of the contactor.

  The risk of molding deformation of the thermoplastic crown is limited, and the absence of ribs or other forms in relief inside the starter support, frees up the volume available to house more bulky components, for example a thrower of larger diameter.

  The extension may come from molding with the crown, or be formed by a piece secured to the ring by fixing means.

Brief description of the drawings

  Other advantages and features will emerge more clearly from the following description of an embodiment of the invention given by way of non-limiting example, and shown in the accompanying drawings, in which: - Figure 1 is. an axial sectional view of a starter equipped with an articulated launcher control lever according to the invention; - Figure 2 shows a sectional view on an enlarged scale of the gearbox crown, which comprises a hinge yoke of a reported pivot axis; Figure 3 shows a side view of Figure 2; Figures 4, 5 and 7 are identical views of Figure 3 of three embodiments of the articulation of the control lever of the launcher; Figure 6 is a vertical sectional view of Figure 7; Fig. 8 is an inside view of the starter carrier at the gear ring of the speed reducer; - Figure 9 is a sectional view along the line 9-9 of Figure 8; - Figure 10 is a sectional view on a larger scale of the reducer of h Figure 1, showing the centering of the ring relative to the support and the cylinder head.

  Description of a Preferred Embodiment

  Referring to Figure 1, the starter 10 comprises an electric motor 1 1 consisting of a stator 12 and a rotor 13 mounted coaxially, the stator 12 surrounding the rotor 13, which is rotatably mounted about an axis 14 inside a cylinder head 15. The latter is secured to the support 16 of the starter to be fixed on a fixed part of the motor vehicle.

  The stator 12 comprises, for example, an inductor winding 17 comprising two pairs of windings 18, which are each wound around a polar mass 19 integral with the cylinder head 15. The polar masses 19 are fixed by means of screws 20 at the cylinder head 15 as described in document FR-A-2,611,096 (FIG. 1). Each winding 18 is composed of a continuous conductor wound around the polar mass 19 in the direction of its thickness so as to form concentric contiguous turns of increasing diameter as best seen in Figures 2 to 5 of EP A 749 194. The axis of each winding 18 is radial relative to the axis 14 of the rotor 13, which constitutes the axis of rotation of the electric motor 11.

  The rotor 13 comprises a sheet metal package provided with grooves for mounting electrical conductors 21 in the form of pins. These conductors 21 are interconnected to form a rotor winding in connection with conductive blades 22 belonging to a collector 23 integral with the shaft 24 of the electric motor 11.

  Brushes 25 rub on the collector slats 22 of the manifold 23 to supply the rotor winding. The brushes 25 belong to a brush holder 26 equipped with guiding cages and receiving brushes, which are biased towards the slats 22 by means of springs 27. The brush holder 26 is integral with a rear bearing 28 having in the central portion a housing for mounting a needle bearing 29. The bearing 28 serves for rotatably mounting the rear end of the shaft 24 of the electric motor 11. The axis of this shaft 24 coincides with the 14 of the rotor 13, and with the axis of the output shaft 43, constituting the starter shaft 30. The rear bearing 29 serves as a centering device at the rear end of the cylinder head 15, and is connected by tie rods 31 to the support 16 of the starter 10.

  The starter 10 also comprises an electromagnetic contactor 32 extending parallel to the electric motor 11 by being radially implanted above it. The contactor 32 has a tank 33 carried by the support 16, and equipped with an excitation coil B provided with at least one winding. The tank 33 is closed at the front by a cover 34 made of electrically insulating material. The fixing of the cover 34 is made by folding the material of the free end of the tank 33. A shoulder of the tank 33 ensures the axial setting of a fixed core 35, which is wedged axially in the other direction by the cover 34 carrying 1 o terminals 36, 37 of power supply.

  The terminals 36, 37 are shaped to each form a fixed contact 38 inside the cover 34. One of the terminals 36 is intended to be connected to the positive terminal of the battery, the other 37 is connected by the intermediate of a cable 39 at the input of the inductor winding 17 of the stator and brushes 25 of positive polarity. During the excitation of the coil B, a mobile core 40 is attracted by magnetic attraction towards the fixed core 35 to simultaneously cause the closing of the contacts of the contactor 32, and the actuation of a control lever 41 of the launcher 30 .

  The output shaft 43 is mounted in a bearing 42 before the support 16, constituted for example by a needle bearing. The rear end of the output shaft 43 has, as described in the document FR-A-2787833, a recess for the arrangement of a sliding bearing 44 for the rotational mounting of the front end of the shaft. 24 of the electric motor 11. This front end is configured to form a sun gear 49 belonging to an epicyclic gear train constituting a speed reducer 45 gear, which is interposed between the output shaft 43 and the shaft 24 of the electric motor 11 .

  The speed reducer 45 comprises a cylindrical ring 46 immobilized in rotation and having an annular skirt toothed internally. The teeth 48 of the ring 46 have an axial orientation, and mesh with planet gears 47 rotatably mounted about axes carried by a transverse plate secured to the rear end of the shaft 43 of the launcher 30. The crown 46 is a molded part, preferably made of rigid thermoplastic material.

  The launcher 30 is slidably mounted on the output shaft 43, and comprises a drive gear 50, a driver 51 actuated by the control lever 41 pivoting, and a free wheel 52 interposed axially between the driver 51 and the pinion 50. The driver 51 is internally provided with helical grooves in complementary engagement with external helical teeth carried by the output shaft 43. The launcher 30 is thus driven by a helical movement when it is moved by the lever 41 against the stop 53 to come, through its pinion 50, in engagement with the starter ring (not shown). It is clear that the freewheel device 52 can be replaced by a coupling device with a conical clutch, of the type described in the document FR-A-2772433.

  The control lever 41 is coupled by its upper end to the movable core 40 of the contactor 32, and comprises in its central part a pivot axis 54, which according to the invention can be integrated partially or totally in an extension of the ring 46 Geared gear reducer 45 toothed gear.

  According to FIG. 1, the extension of the ring gear 46 of the gearbox 45 consists of one or two flat tongues 55 each comprising a serai-cylindrical bearing 56 intended to receive the pivot axis 54. This bearing 56 constitutes means Lever 41 is supported on the rear part of the hinge, while the front part of the hinge is formed by a bearing-shaped housing on the support 16. The remaining space between the rear of the tongues 55 and the face bearing 57 of the contactor 32 is occupied by a sealing pad 58 of elastomer capable of absorbing dimensional variations.

  In this exemplary embodiment, the semi-cylindrical bearing 56 is molded with the tongues 55 extending the ring 46, and the pivot axis 54 is molded with the control lever 41. The advantage of a such assembly avoids the use of an insert to achieve the bearing surface and articulation of the lever 41, and simplifies the machining operations for maintaining play free parts to assemble.

  FIGS. 2 to 7 show other exemplary embodiments in which the pivot axis 54 of the lever 41 is totally integrated in the ring 46 of the gearbox 45.

  With reference to FIGS. 2 and 3, the control lever 41 comprises hinge housings 59 at the upper part for connection with the movable core 10, and a fork 60 at the lower part intended to engage with the 51. The annular skirt 61 with internal teeth 48 of the ring 46 is connected to a radial flange 62, which is pierced at its center with a hole 63 coaxially traversed by the output shaft 43. The ring 46 of the gearbox 45 is provided with a yoke 64 allowing the insertion of the pivot pin 54 for the articulation of the lever 41. The yoke 64 is advantageously molded with the ring 46, while the pivot axis 54 is a piece reported through a hole of the lever 41 to be housed in orifices 65 aligned with the yoke 64.

  In Figure 4, the yoke 64 of the ring 46 is formed by two tabs 64a, 64b elastic provided with two orifices 65 aligned. The pivot axis 54 is molded with the lever 41, and can be introduced into the orifices 65 after transverse spacing of the tabs 64a, 64b.

  In FIG. 5, the two elastic tabs 64a, 64b of the yoke 64 are each provided with a pin 66 which is clipped into an annular groove 67 of the control lever 41 to constitute the articulation of the latter on the ring 46.

  In the variant of FIGS. 6 and 7, the yoke 64 provided on the extension of the toothed ring gear 46 comprises a U-shaped cradle 68 in which the pivot axis 54 is engaged. The latter can be integrated with the lever of FIG. 41, in particular by molding, or be reported transversely in an orifice of the lever 41.

  It is clear that the clevis 64 housing the pivot axis 54 may be constituted by a piece fixed on the toothed crown 46, instead of coming directly from molding with the gearbox crown, as in the examples of FIGS. 7. The hinge piece can be mechanically secured to the crown by any method of attachment, including welding, gluing, clipping, crimping, sliding in a T-slot or dovetail.

  The integrated assembly of the articulation of the control lever 41 on the ring 46 1 o of the gearbox 45, as shown in the embodiments of Figures 2 to 7, provides the following advantages: simplification of the machining of the support 16, the bearing face 57 of the contactor 32, and the housing of the support of the lever 41 can remain gross, the sealing pad 58 made of elastomer is a less expensive piece than the support of the lever according to the document FR -A-2787833.

  With reference to FIGS. 8 and 9, the rotational locking of the toothed crown 46 is advantageously achieved by the yoke 64 which is housed in a cavity 69 of complementary shape formed in the support 16. In addition to its function of articulating the control lever 41, the yoke 64 simultaneously constitutes a male stop element, which is dimensioned to fit the width of the cavity 69. The latter, already arranged for the positioning and guiding of the control lever 41, constitutes a female retaining element of the yoke 64 for the immobilization in rotation of the ring gear 46 of the gearbox 45.

  The starter support 16 is thus simplified with respect to that of the documents FR-A-2787833 and FR-A-2767157, since it does not require specific ribs or grooves for the rotational stop of the ring gear 46. the absence of ribs or other raised protuberances inside the starter support 16 frees up the available space for accommodating larger components, for example a larger diameter launcher 30.

  The yoke 64 has in the example of Figures 8 and 9, a double function of articulation of the lever 41 and stopping rotation of the ring 46, which also simplifies the manufacture of the latter. The risk of molding deformation of the crown 46 thermoplastic are thus limited.

  FIG. 10 shows the device for positioning the ring 46 of the gearbox 45 relative to the support 16 of the starter and the cylinder head 15 of the electric motor 11. The ring 46 has a flange 73 having a first bearing surface 70 situated in the same plane that the second support surface 71 of the support 16 of 1 o starter, and the third bearing face 72 of the yoke 15 of the inductor.

  The centering of the toothed crown 46 in the support 16 is provided by h first bearing surface 70 of the collar 73. The centering of the cylinder head 15 on the crown 46 is performed on the outside diameter of the collar 7. The third bearing face 72 of the yoke 15 is in contact with the second bearing face 71 of the support 16, which permanently guarantees the electrical continuity between the yoke and the support.

  The locking in axial translation of the ring 46 of the gearbox 45 results from the presence of the radial collar 73 which bears against the second bearing face 71 of the support 16, and a stop boss 74. The latter is obtained by a form pressed into the cylinder head 15, and abutting against the skirt 61 opposite the flange 73.

  The flange 73 of centering and positioning of the ring 46 simplifies the machining operations, and reduce the starter rating chains. Only the second bearing face 71 of the support 16 must be machined.

  As is evident from the description and the drawings, the tongues 55 and the tabs 64a, 64b of the yoke 64 form between them a space for the passage of the control lever 41, here plastic. The tabs 55 correspond to the tabs 64a, 64b of the yoke 64 with only one bearing 56.

  The lever 41 is connected to the movable core 40 via a rod hitched elastically to the movable core 40 as partially visible in Figure 1, and better visible in Figure 2 of the document FR-A-2787833. The fork 60 comprises at its lower end two fingers penetrating into a groove in the driver 51, one of the sides of the groove being formed by a washer snapped onto the driver, as described in document FR-A -2687736.

  The cylindrical cylinder head 15 like the tank 33, has a simplified structure thanks to the invention, since the ring 46 has an extension, i o here having a generally transverse orientation. This extension extends substantially in the extension of the flange 62 of the ring 46 of hollow form, serving as housing the speed reducer epicyclic train.

Claims (7)

claims   Motor vehicle starter comprising: an electric motor (11) for driving a launcher (30) in rotation with the interposition of an epicyclic gear speed reducer (45) comprising a fixed crown (46) with a skirt (61) internally toothed, - immobilization means in rotation of said ring gear (46) in the support (16) of the starter, and a contactor (32) for supplying the electric motor (11) and actuating a lever of control (41) engaged with the driver (51) of the launcher (30), characterized in that the ring gear (46) of the gearbox (45) has an extension formed as a male stop element engaged in a cavity (69). ) of the support (16) receiving the control lever (41).   2. Starter according to claim 1, characterized in that the extension of the ring (46) adapts to the width of the cavity (69) serving as a female element 20 for positioning and guiding the control lever (41). ).   3. Starter according to claim 1 or 2, characterized in that the extension of the ring (46) comprises a yoke (64) for articulation of the control lever (41).   4. Starter according to claim 3, characterized in that the yoke (64) has a shape complementary to that of the cavity (69).   5. Starter according to one of claims 1 to 4, characterized in that the extension is molded with the ring (46).   6. Starter according to one of claims 1 to 4, characterized in that the extension is formed by a part secured to the ring (46) by fixing means.   7. Starter according to one of claims 1 to 6, characterized in that a stud (58) of flexible material is interposed between the extension of the ring (46) and a bearing face (57) of the contactor ( 32).