FR3042231B1 - MOTOR VEHICLE STARTER LAUNCHER WITH PROTECTIVE HOOD - Google Patents

Abstract

The invention relates mainly to a launcher (10) of a motor vehicle starter comprising: - a pinion carrier (13), - a pinion (12) mounted to move in translation on said pinion carrier (13) between a rest position and a retracted position and is integral in rotation with said pinion carrier (13), - a spring (25) mounted between said pinion (12) and a shoulder (28) of said pinion carrier (13) exerting a restoring force on said pinion (12) to the rest position, characterized in that said pinion (12) in its retracted position comprises an abutment face (30) in contact with an abutment face (31) of said pinion carrier (13), and in that, in the rest position, a variable volume (V) is delimited between said abutment face (30) of said pinion (12) and said abutment face (31) of said pinion carrier (13), and in that a protective case (34) has at least a first cover (35) mounted around said variable volume (V).

Description

The invention relates to a starter starter of a motor vehicle with a protective cover. The invention finds particularly advantageous, but not exclusive, application with vehicles equipped with the function of stopping and automatic restarting of the engine (function called "stop and start" in English).

In order to start a motor vehicle engine, it is known to use a rotating electric machine in the form of a starter with a launcher capable of transmitting rotational energy from the starter to a crankshaft of the engine through the engine. a start-up crown. For this purpose, the launcher is movably mounted in translation on a drive shaft between a rest position, in which the launcher locates at a distance from a starting ring of the heat engine at an active position in which the launcher is engaged. with the starter ring via a drive pinion.

This launcher can undergo significant mechanical shocks during operation of the starter, especially when launching the thermal engine. Indeed, the teeth of the pinion can slide against the teeth of the starter ring before engaging between them, which can tendten a phenomenon of milling teeth of the pinion.

In order to limit the damage to the teeth of the pinion, it is known to use a pinion cooperating with the pinion carrier by means of longitudinal grooves, so that the pinion can move back relative to the pinion carrier in case of impact. A return spring ensures the return of the pinion in its initial position after the shock. However, such a device does not preserve the teeth of the pinion if dirt penetrates into the notches and prevent the movement of the pinion. The invention aims to effectively remedy this disadvantage by proposing a starter starter motor vehicle comprising: - a pinion carrier, - a pinion mounted movable in translation on said pinion carrier between a rest position and a retracted position and is secured in rotation with said pinion carrier, - a spring mounted between said pinion and a shoulder of said pinion holderextracting a restoring force on said pinion to the rest position, characterized in that said pinion in its retracted position has an abutment surface in contact with a pinion abutment face of said pinion carrier, and in that, in the rest position, a variable volume is delimited between said abutment faction of said pinion and said abutment face of said pinion carrier, andin that a protective case comprises at least one first hood mounted around said variable volume. The invention thus makes it possible, thanks to the use of the protective casing, to avoid the introduction of dirt inside the launcher likely to damage the operation of the starter.

According to one embodiment, the at least one first cover is pressed by the spring against a shoulder of the pinion carrier or a rear radial face of the shoulder gear.

According to one embodiment, in the rest position, an axial displacement distance of said pinion relative to said pinion carrier is less than the sum ofdistances between turns of said spring. This prevents the abutment is produced in contiguous turns spring.

According to one embodiment, in the rest position, the axial clearance distance of said pinion relative to said pinion carrier is less than the distance between the free end of the hood closest to the teeth of said pinion and a faceradial teeth of said pinion.

According to one embodiment, said protective housing comprises a second cover integral with said pinion and slidable with respect to said first cover.

According to an example of the previous embodiment, the first cover is pressed by the spring against a shoulder of the pinion carrier and in that the second cap is pressed by the spring against a rear radial face of the shoulder gear.

In one embodiment, in the rest position, an axial clearance distance of said pinion relative to said pinion carrier is less than the axial clearance in which one of the covers moves relative to the other cover.

In one embodiment, said first cover or said second cover comprises a radial recess for limiting the radial expansion of at least one turn of said spring.

According to one embodiment, said second cover slides on the outside of said first cover.

In one embodiment, said second cover slides inside said first hood.

According to one embodiment, said first cover and said second covercompresse a portion having an inner diameter substantially equal external diameter of the turns of said spring.

According to one embodiment, said protective housing comprises a snap-in system for snapping said two covers together.

According to one embodiment, said latching system comprises at least one retaining element formed on an inner periphery of one of the hoods directed in one direction towards an axis of said launcher and a second retaining elementprovided on an outer periphery of the other hood directed in the opposite direction said direction towards the axis of said launcher, said two retaining elements being intended to cooperate with each other by snapping.

According to one embodiment, at least one of the two retaining elements is formed by a flange.

According to one embodiment, said inner cover located inside said outer cover is held axially by said outer cover.

According to one embodiment, said first cover is located between said spring and said variable volume. The invention also relates to a starter motor for a motor vehicle engine characterized in that it comprises a launcher as previously defined. The invention will be better understood on reading the description which follows and on examining the figures that accompany it. These figures are given as illustrative but not limiting of the invention.

Figure 1a shows a longitudinal sectional view illustrating a first embodiment of a protective housing belonging to a starter launcher according to the present invention;

Figure 1b is a perspective view of the protective housing used with the launcher of Figure 1a;

Figure 2 shows a partial longitudinal sectional view illustrating a second embodiment of a protective housing belonging to the starter spreader according to the present invention;

Figure 3a shows a longitudinal sectional view illustrating a third embodiment of a protective housing belonging to a starter launcher according to the present invention;

Figure 3b is a perspective view of the protective case used with the launcher of Figure 3a;

Identical, similar or similar elements retain the same reference from one figure to another.

FIG. 1a shows a launcher 10 slidably mounted on a drive shaft 11. This launcher 10 comprises a drive pinion 12 installed on a pinion carrier 13, which is mounted on the drive shaft 11 via gearing systems. 16. These rotation guiding systems 16 here take the form of bearings but may alternatively take the form of ball bearings. The axis X of the shaft 11 is substantially merged with the axis of the pinion carrier 13 and the pinion 12 and is considered to be the axis of the launcher 10.

In addition, a free wheel roller 19 is interposed axially between the pinion carrier 13 and a driver 20 configured to be actuated by a control lever. The sleeve-shaped pinion carrier 13 has a rear end configured to form the inner race of the freewheel 19. Furthermore, the driver 20 is extended axially forward by a dowel 21 configured internally to form the outer track of the rouelibre 19 and house the springs acting in known manner on the rollers. The driver 20 is also internally provided withhelical splines in complementary engagement with externalhelical teeth carried by the drive shaft 11. The launcher 10 is thus driven by a helical movement when it is moved by the control lever towards the stop 24 to move from a position dpospos in which the pinion 12 is positioned away from the starter ring of the engine to an active position in which the pinion 12 engages with the starter ring of the engine. The abutment 24pourra for example be constituted by a circlip inserted in a groove of corresponding shape of the shaft 11.

In order to limit the damage to the teeth of the pinion 12 in the event of an impact with the starter ring, the pinion 12 is movably mounted on the pinion carrier 13 between a rest position and a retracted position. The pinion 12 is furthermore integral in rotation with the pinion carrier 13. For this purpose, the pinion 12 cooperates with the pinion carrier 13 via longitudinal grooves of complementary shape.

A spring 25 is mounted between the pinion 12 and a shoulder 28 of the pinion carrier 13. This spring 25 is intended to exert a restoring force on the pinion 12 to the rest position. The pinion 12 in its retracted position comprises a stop face 30 in contact with a corresponding abutment face 31 of the pinion carrier 13. The axial distance between the two faces, which is started in the rest position, corresponds to the axial clearance distance Dof the pinion 12, that is to say at the axial distance over which the pinion 12 can move relative to the pinion carrier 13 to move from the position derepos to the retracted position or vice versa. The clearance distance Dest is less than the sum of the distances between the turns of the spring 25. It is thus avoided that the abutment contact between the pinion 12 and the pinion carrier 13 is produced by contiguous turns of the spring 25.

In addition, a protective casing 34 is mounted around the variable volume V delimited, in the rest position, between the abutment face 30 of the pinion 12 and the end stop 31 of the pinion carrier 13.

This protective case 34 comprises a first cover 35 integral with the pinion carrier 13. As can be seen more clearly in FIG. 1b, the cover 35 comprises a transverse wall 36 abutting against the shoulder 28 of the pinion gear 13 and pierced centrally. to allow the passage of an axial portion 37 of the pinion carrier 13. The cover 35 further comprises an annular wall 38 and a radial recess 39 extending between the annular wall 38 and the transverse wall 36. This recess 39 is intended to limit the radial expansion of at least one turn of the spring 25.

The protective casing 34 further comprises a second integral cover 40 of the pinion 12 adapted to slide inside the first cover 35. The second cover 40 comprises a transverse wall 41 abutting against a rear faceradial 44 of the pinion 12 forming a shoulder and having a central hole for allow the passage of an axial portion 42 of the pinion 12 from the face44. This transverse wall is in this case pressed against the faceradial 44 through the spring. Thus, the spring plates the first and second cap respectively against the shoulder 28 of the pinion carrier and the radial surface of the pinion. The cap 40 further comprises an annular wall 43 having an external diameter substantially equal to the internal diameter of the paroiannulaire 38 and an inner diameter substantially equal to the outside diameter of the turns of the spring 25. This limits the radial expansion of the turns duressort 25 during the rotation of the pinion 12. It will be considered that two "substantially equal" diameters have between them a difference of the length at most equal to 5% of the average diameter between these two diameters.

According to this configuration, in the rest position, the distance Daxial clearance of the pinion 12 with respect to the pinion carrier 13 is less than the distance L1 between the free end of the cowl 35 closest to the pinion teeth 12 and the radial face 44 of the pinion. pinion 12. In addition, in the rest position, the clearance distance D is less than the axial play J in which one of the covers moves relative to the other. This ensures that the stop contact is not made by a part of the housing 34 but only by the abutment faces 30, 31 of the pinion 12 and the pinion carrier 13.

In the embodiment of Figure 2, the protective housing 34comporte additionally a latching system 47 to snap the twocaps 35, 40 with each other. For this purpose, the latching system 47 comprises a retaining element 481 formed on an inner periphery of one of the hoods directed in the direction towards the X axis and a second retaining element 482 formed on an outer periphery of the other directed hood. in the opposite direction to the X direction.

In the exemplary embodiment, the two retaining elements 481, 482 are constituted by flanges. The flange 482 carried by the hood having an outer diameter greater than the internal diameter of the flange 481 carried by the outer cover, the insertion of the inner collar 48 is madepossible by the elastic deformation of the flanges 481, 482. Alternatively, at least one collars 481, 482 may be replaced by a set of legs angularly distributed regularly. The internal cowl 35 located inside the outer cowl 40 is thus retained axially by the outer cowl 40.

Alternatively, the assembly can be reversed, that is to say that the first cap 40 slides inside the second cover 35, which then includes the catch 39 to prevent the expansion of at least one turn of the spring 25.

In the variant embodiment illustrated in FIGS. 3a and 3b, the housing has a single cover 35 'comprising an annular wall 51 of axial orientation positioned between the spring 25 and the variable volume V, as well as a radial flange 52 extending towards the outside intended to bear against the shoulder 28 of the pinion carrier 13. In this case, the cap is pressed by the spring 25 against the shoulder 28. The annular wall 51presente an inner diameter substantially equal to the outer diameter of axial convonçon 37, 42 of the pinion 12 and the pinion carrier 13. The paroiannulaire 51 has an outer diameter substantially equal to the inner diameter of the turns of the spring 25. As for the other embodiments, in the rest position, the clearance distance D is less than the distance LT between the free end of the hood 35 'closest to the teeth dupignon 12 and the radial face 44 of the teeth of the pinion 12.

In another example, the hood 35 'is mounted upside down with respect to Figure 3a, that is to say that the radial flange 52 of the hood is mounted against the radial shoulder forming the pinion. In this example not illustrated, the shoulder at the pinion to center the spring would be located on the pinion door between the radial face 31 and the shoulder 28.

It is clear that the freewheel device 19 can be replaced by a conical clutch coupling device of the type described in document FR2772433 or a clutch with several friction discs.

Of course, the foregoing description has been given by way of example only and does not limit the scope of the invention of which one would not go out by replacing the various elements by all other equivalents.

Claims (3)

Motor vehicle starter (10) comprising: - a pinion carrier (13), - a pinion (12) mounted to move in translation on said pinion carrier (13) between a rest position and a retracted position and is integral in rotation with said pinion carrier (13), - a spring (25) mounted between said pinion (12) and a shoulder (28) of said pinion carrier (13) exerting a restoring force on said pinion (12) versla rest position, characterized in that said pinion (12) in its retracted position comprises an abutment face (30) in contact with an abutment face (31) of said pinion carrier (13), and that, in the rest position, a variable volume (V) is defined between said abutment face (30) of said pinion (12) and said abutment face (31) of said pinion carrier (13), in that a protective case (34) comprises at least one firstcapot (35) mounted around said variable volume (V), and in that, in the rest position, an axial clearance distance (D) of said pinion (12) by r supply to said pinion carrier (13) is less than a distance between the free end of the cowl (35) closest to the teeth of said pinion (12) and a radial face (44) of the teeth of said pinion (12). 2. Launcher according to claim 1, characterized in that, in positionrepos, an axial clearance distance (D) of said pinion (12) in relation to said pinion carrier (13) is less than a sum of the distances between despires of said spring (25). ). 3. Launcher according to any one of claims 1 to 2, characterized in that said protective housing (34) comprises a second cover (40) integral with said pinion (12) and slidable with respect to said first cover (35). 4. Launcher according to claim 3, characterized in that, in positionrepos, an axial clearance distance (D) of said pinion (12) in relation to said pinion carrier (13) is less than an axial clearance (J) in which the one of the hoods (35, 40) moves relative to the other hood (35, 40). 5. Launcher according to claim 3 or 4, characterized in that said first cap (35) or said second cap (40) comprises a décrochementradial (39) for limiting a radial expansion of at least one spiredudit spring (25). 6. Launcher according to any one of claims 3 to 5, characterized in that said second cover (40) slides outside said first cover (35). 7. Launcher according to any one of claims 3 to 5, characterized in that said second cover (40) slides inside said first cover (35). 8. Launcher according to any one of claims 3 to 7, characterized in that said first cover (35) and said second cover (40) comprisea portion having an inner diameter substantially equal to the outer diameter of the turns of said spring (25). 9. Launcher according to any one of claims 3 to 8, characterized in that said protective housing (34) comprises a latching system (47) for snapping said first and second compartments (35, 40) one with the other. 10. Launcher according to any one of claims 3 to 9, characterized in that said latching system (47) comprises at leasta retaining element (481) formed on an inner periphery of a pods (35) directed in a direction towards an axis (X) of said launcher (10) and a second retaining element (482) formed on an outer periphery of the other hood (40) directed in the opposite direction to said direction towards the axis (X) of said launcher (10) said two retaining elements (481, 482) being intended to co-operate with each other by snap-fastening. 11. Launcher according to any one of the preceding claims, characterized in that the at least one first cover is pressed by the spring against a shoulder of the pinion carrier or a rear radial face of the pinion formedpaulementpaulement. 12. Launcher according to any one of claims 3 to 11, characterized in that said second inner cover (40) located inside said first outer cover (35) is retained axially by said outer cover (35). 13. Launcher according to any one of claims 1 to 12, characterized in that said first cover (35 ') is located between said spring (25) and said variable volume (V). 14. Starter for a motor vehicle engine enginecharacterized in that it comprises a launcher (10) as defined in any of the preceding claims.