FR3065123A1 - TIMING WASHER USED IN A STARTER - Google Patents

Abstract

Electric motor comprising a motor shaft held in rotation by at least one rotational bearing, an axial locking means of the motor shaft, a cap defining a reserve of lubricant for lubricating the rotation bearing, and a shim washer (12 ) interposed between the reserve and the rotational bearing and arranged so that the lubricant migrates from a first face (16) of the wedge washer (12) to a second face (18) of the wedge washer (12), the wedging washer (12) having a central opening (14) through which the motor shaft passes, characterized in that the wedge washer (12) comprises at least one secondary opening (20).

Description

Holder (s): VALEO ELECTRIC EQUIPEMENTS MOTOR Simplified joint-stock company.

Extension request (s)

Agent (s): VALEO EQUIPEMENTS ELECTRIQUES MOTOR Simplified joint-stock company.

* 54) SETTING WASHER USED IN A STARTER.

FR 3 065 123 - A1 (57) Electric motor comprising a motor shaft kept in rotation by at least one rotation bearing, an axial locking means of the motor shaft, a cap delimiting a reserve of lubricant intended to lubricate the bearing rotation, and a shim washer (12) interposed between the reserve and the rotation bearing and arranged so that the lubricant migrates from a first face (16) of the shim washer (12) to a second face (18) of the shim washer (12), the shim washer (12) having a central opening (14) through which the drive shaft passes, characterized in that the shim washer (12) comprises at least one secondary opening ( 20).

Shim washer used in a starter

The present invention relates to thermal engine starters for a motor vehicle, comprising in particular an electric motor inside which rotates a motor shaft kept in rotation by a front bearing and by a rear bearing.

A starter has a limited lifespan which is in particular conditioned by the frequency with which it is requested, that is to say by the number of starting cycles to which the starter is subjected. This parameter varies according to the manufacturer and according to the technological level of the vehicle. Such a starter therefore needs optimized lubrication of its components in order to have an acceptable service life, without premature wear due to unforeseen friction. It is thus understood that a deficiency in the lubrication of the starter is a factor limiting the life of the starter.

Today's vehicles may have a thermal engine standby system that automatically stops and restarts the thermal engine at a high frequency. This is particularly the case for vehicles equipped with a "StopStart" function where the engine stops as soon as the vehicle is stopped in traffic. This type of vehicle requires suitable equipment, in particular a high-tech starter designed for a high frequency of use, that is to say with a high number of starting cycles. This high frequency of use requires adequate lubrication in the starter. Insufficient lubrication in the starter causes premature wear of the rear bearing, by prematurely wearing out the associated bearing, causing the starter to break.

The prior art does not offer economically satisfactory solutions for increasing the life of the starter fitted to vehicles with a high number of starting cycles. A solution should therefore be found to increase the life of the starters for this type of vehicle.

The invention provides an efficient and durable lubrication solution for the electric motor, in particular the rear bearing and in particular the rear bearing throughout the life of the electric motor when the latter is operated in a starter with a high frequency of use.

The invention therefore aims to solve the drawbacks described above by providing an electric motor comprising a motor shaft kept in rotation by at least one rotation bearing, a means of axial locking of the motor shaft vis-à-vis of the rotation bearing, arranged in particular to axially lock the motor shaft relative to the rotation bearing, a cap delimiting a reserve of lubricant intended to lubricate the rotation bearing, and a shim washer interposed between the reserve and the rotation bearing and arranged so that the lubricant migrates from a first face of the shim washer to a second face of the shim washer, the shim washer having a central opening, for example circular, through which the drive shaft passes. The electric motor according to the invention is recognizable in that the timing washer comprises at least one secondary opening.

The design and arrangement of the shim washer provides effective and lasting lubrication of the motor shaft, the rotation bearing and any bearing associated with the rotation bearing throughout the life of the electric motor, thus avoiding premature starter wear.

Different aspects and variant embodiments of the invention described below can be taken together or separately.

It will be noted that the first face of the setting washer is that which is directly opposite the lubricant reserve.

The second face of the wedge washer is the one which is opposite to the first face of the washer with respect to a body of the latter formed by the material of the washer arranged between the first face and the second face. Taken in another frame of reference, this second face of the washer is the one which is directly opposite the rotation bearing, in particular in contact with a bearing constituting the rotation bearing.

Advantageously, the timing washer comprises a secondary opening which opens into the central opening of the timing washer. It is understood here that the secondary opening and the central opening intersect, the secondary opening then forming an outgrowth of the central opening. The lubricant is thus more particularly guided towards the friction zone between the motor shaft and the rotation bearing.

According to one aspect of the invention, this secondary opening is delimited by a first contour in the form of an arc of a circle and / or according to the variant embodiment, in the form of one or more straight line segments.

According to a preferred variant of the invention, the electric motor comprises a wedging washer comprising three secondary openings angularly distributed around a central axis of the central opening, at the periphery of an internal edge of the wedging washer which delimits the central opening. Preferably, each secondary opening is arranged angularly at 120 ° from one another around the central axis. In this way, each secondary opening is centered on a radial plane distinct from the adjacent secondary opening. By "radial plane" is meant a plane which extends along a radius of the washer by bearing along the central axis. These variant embodiments offer a homogeneous migration of the lubricant.

Alternatively, the angular distribution of the secondary openings can be heterogeneous so as to concentrate the lubricant on a particular angular sector of the friction zone between the motor shaft and the rotation bearing.

According to another aspect of the invention, the shim washer has a ratio between an internal radius, corresponding to the radius of the central opening and an external radius of the shim washer, between 0.5 and 2, preferably between 0, 8 and 1.2. The internal radius corresponds to a first distance between the central axis and an internal edge of the shim washer. The outer radius extends between the central axis and an outer edge of the shim washer.

In addition, the shim washer has a ratio between at least one maximum dimension of the secondary opening and an external radius of the shim washer between 0.1 and 0.8 preferably between 0.25 and 0.33. The maximum dimension of the secondary opening is measured between the central axis of the central opening and a point on the internal contour of the secondary opening which is radially furthest from the central axis. This maximum radius of the secondary opening can also be defined by a circle which tangents at least two secondary openings.

In an alternative embodiment, the electric motor comprises a shim washer comprising a secondary opening which is delimited by at least one oblique internal contour, that is to say which extends along a direction which forms with the 'one and / or the other of the faces delimiting the setting washer an angle between 25 ° and 85 °. Alternatively, the internal contour can extend in a direction perpendicular to one and / or the other of the faces delimiting the setting washer. The internal contour is the face of the washer which delimits the secondary opening between the first face of the shim washer and the second face of the shim washer. The oblique or straight internal contour forms a path which guides the lubricant towards the friction zone mentioned above.

According to another aspect of the invention, the electric motor comprises a timing washer having a first section of the secondary opening taken in a first plane of the first face which is equal to a second section of the secondary opening taken in a second shot of the second side. A passage section of the secondary opening is therefore identical, or substantially identical, between the first face and the second face of the setting washer.

According to an alternative embodiment, the first section of the secondary opening taken in the first plane of the first face is different from the second section of the secondary opening taken in the second plane of the second face. Advantageously, the first section is larger than the second section. Alternatively, the second section is greater than the first section, thereby providing a greater distribution of the lubricant at the outlet of the shim washer, that is to say at the level of the second face of the shim washer. It is understood here that a passage section of the secondary opening is variable between the first face and the second face of the shim washer.

The lubricant is contained in the reserve, then it migrates from the first face of the shim washer to the second face of the shim washer. More specifically, the lubricant passes through the shim washer passing through the first section, otherwise called “inlet section” of the secondary opening, then passes into the passage section of the secondary opening and leaves the shim washer. by the second section, otherwise called “outlet section” of this same secondary opening.

It will be noted that the setting washer is preferably made of a material chosen from Steel such as zinc-plated mild steel or blued steel etc.

The electric motor described in this document is intended to be used in a thermal engine starter. This is why the invention also covers a starter for an internal combustion engine comprising an electric motor as described in this document, such an electric motor being that which starts the internal combustion engine.

Other characteristics, details and advantages of the invention will emerge more clearly on reading the description given below by way of indication in relation to the drawings in which:

Figure 1 is a sectional view of part of an electric motor where the invention takes place, Figure 2 is a top view in perspective of a timing washer included in the electric motor illustrated in Figure 1 , Figures 3a and 3b are top views of a timing washer included in the electric motor, according to two alternative embodiments, Figures 4a, 4b, 4c and 4d are views in axial section of four embodiments of '' a setting washer.

It should first be noted that if the figures show the invention in detail for its implementation, they can of course be used to better define the invention if necessary. It should also be noted that, in all of the figures, similar elements and / or fulfilling the same function are indicated by the same reference.

The embodiments which are described below are in no way limiting; it is possible in particular to imagine variants of the invention comprising only a selection of characteristics described below, isolated from the other characteristics described, if this selection of characteristics is sufficient to confer a technical advantage or to differentiate the invention from the state of the prior art.

In particular, all the variants and all the embodiments described can be combined with one another if nothing is technically opposed to this combination.

FIG. 1 shows a part of an electric motor 2, in particular a motor arranged in a starter fitted to a heat engine of a motor vehicle. This electric motor 2 comprises in particular a motor shaft 4 kept in rotation by at least one rotation bearing 6, called "rear bearing". Such an electric motor 2 also comprises at least one other rotation bearing, called the "front bearing". The rotation bearing 6 is for example formed by a circular barrel 3 which is part of a rear housing 5 which delimits the rear part of the electric motor 2. The rotation bearing 6 also comprises a bearing 7 formed for example by a ring of circular section whose internal diameter is adjusted to an external diameter of the motor shaft 4. The rotation bearing 6 and the motor shaft 4 are therefore in rotating contact with each other at a friction zone 9.

The electric motor 2 according to the invention also comprises an axial locking means 8 of the motor shaft 4 relative to the rotation bearing 6. Such an axial locking means 8 has the role of limiting a translational movement between the shaft motor 4 and the rotation bearing 6 along an axis of rotation of the motor shaft 4. According to an exemplary embodiment, the axial locking means 8 takes the form of a circlip engaged in a groove produced at the outer periphery of the motor shaft 4.

This electric motor 2 also comprises a cap 11 delimiting a reserve 10 capable of containing a lubricant dedicated to the friction zone 9. This cap 11 covers an end part of the motor shaft 4 and engages in a sealed manner on the housing sealed rear 5. Axially, the cap 11 covers the rotation bearing 6, the shim washer 12, the axial locking means 8 and the drive shaft 4. The reserve 10 is delimited by these members.

This reserve of lubricant can contain from 0.5 to 1 g of lubricant, preferably from 0.5 to 0.8 g. This reserve 10 is intended to supply lubricant to the rotation bearing 6 throughout the life of the starter. Preferably, the lubricant used is a synthetic lubricating grease preferably comprising thickening elastomers of polyurea.

The electric motor 2 also comprises a shim washer 12. This shim washer 12 is covered axially by the reserve 10 and is disposed between the reserve 10 and the rotation bearing 6. This shim washer 12 has at least one central opening 14 circular central axis O through which the motor shaft 4 passes. This setting washer 12 is disposed between an end edge of the pad 7 and a wall which delimits the axial locking means 8.

The arrangement of the electric motor 2 is such that the lubricant distributed by the reserve 10 migrates from a first face 16 of the shim washer 12 to a second face 18 of the shim washer 12, so as to lubricate the friction zone 9.

As visible in FIG. 2, the first face 16 of the wedging washer 12 extends along a first plane P. Once installed on the electric motor 2, the first face 16 adjoins the reserve 10. The second face 18 s 'extends along a second plane P' which can advantageously be parallel to the first plane P. This second face 18 directly adjoins the rotation bearing 6. These two planes P, P 'are orthogonal to the central axis O of the setting washer 12. The shim washer 12 has a thickness configured as a function of the axial shimming needs in the motor shaft 4 in the electric motor 2. The term thickness is understood to mean the dimension extending transversely between the two planes P, P ', c 'that is to say the distance which extends between the first face 16 and the second face 18 of the wedging washer 12 measured perpendicularly to the latter.

According to the cases illustrated in FIGS. 2, 3a and 3b, the setting washer 12 is circular with a central opening 14 of circular shape and of central axis O, delimited by an internal edge 22 and having an internal radius RI. The shim washer 12 is further defined by an outer radius R2, extending between the central axis O and an outer edge 23. The inner edge 22 defines an inner diameter of the shim washer 12 and the outer edge 23 defines a outer diameter of the shim 12.

According to the invention, the wedging washer 12 has at least one secondary opening 20, in particular three secondary openings 20, opening for example in the central opening 14. Alternatively, the invention also covers the use of a wedging washer with a central hole and one or more secondary openings separate from the central hole.

The configuration of the shim washer according to the invention facilitates the migration of lubricant towards the rotation bearing, in particular by increasing, while controlling it, the lubricant passage section.

According to an embodiment visible in Figures 2, 3a and 3b, the secondary opening 20 is located on the periphery of the internal edge 22 of the central opening 14. This secondary opening 20 is delimited by a first contour 24 in the form of 'arc of a circle, or according to a variant embodiment not illustrated, in the form of straight lines joining edges which delimit a junction between the central opening 14 and the secondary opening 20.

Figures 3a and 3b show the same variant embodiment, according to which the first contour 24 is in the form of a circular arc. However, these two figures respectively represent a first and a second separate embodiment according to which the secondary opening 20 has a separate maximum dimension pl. The maximum dimension pl of the secondary opening 20 extends between the central axis O and a point of the first contour 24 which delimits an edge of the secondary opening 20, in particular the point of the first contour 24 furthest radially from the central axis O. This maximum dimension pl therefore determines the radial position of the secondary opening 20 relative to the central opening 14.

Figures 3a and 3b illustrate a second difference. Indeed the secondary opening 20 is circular in shape and its diameter visible in Figure 3b is larger than its diameter visible in Figure 3a. According to this last figure, the diameter of the secondary opening (s) 20 is between 1 and 2, while the diameter of the secondary opening (s) 20 of the setting washer of FIG. 3a is between 4 and 5.

The second embodiment illustrated in FIG. 3b allows a migration of a larger quantity of lubricant from the first face 16 towards the second face 18 of the setting washer 12.

According to the invention, the ratio between the maximum dimension pl of the secondary opening and the external radius R2 of the shim washer 12 is between 0.1 and 0.8, preferably between 0.25 and 0.33. It will be understood that this ratio differs according to the two embodiments illustrated in Figures 3a and 3b.

According to these two embodiments, the ratio between the internal radius RI and the external radius R2 can be between 0.5 and 2, preferably between 0.8 and 1.2.

Note that according to an embodiment not illustrated, the shim washer 12 may include a plurality of secondary openings 20 of different sizes and / or shape.

As defined above and illustrated in FIGS. 2, 2a and 3b, the setting washer 12 may have several secondary openings 20. Each secondary opening 20 may be arranged in a separate radial plane P1, P2 or P3. “Radial plane” is understood to mean any plane extending radially from the central axis O, that is to say extending towards the outside of the setting washer by bearing on the central axis O It will be understood that the setting washer 12 can equally include N secondary openings 20, in particular between three and six secondary openings.

According to the embodiment illustrated in these figures, each secondary opening 20 is arranged at 120 ° from one another around the central axis O. It will be understood that such a distribution can be adapted as a function of the lubricant needs. of a determined angular sector of the friction zone 9. This may be the case in particular when the longitudinal axis of the motor shaft 4 is in the horizontal position and where it will be advantageous to supply the upper part of the zone of priority friction 9, the lubricant tending to naturally descend towards a lower part of the friction zone 9.

FIGS. 4a to 4d illustrate views in axial section of four embodiments. The cutting plane passes through the central axis O and two secondary openings 20 are visible.

The first and second cases illustrated respectively in FIGS. 4a and 4b are a wedging washer 12 having secondary openings 20, each comprising a first section 28 taken in the first plane P of the first face 16, equal to a second section 30, taken in the second plane P 'of the second face 18. The secondary opening 20 is thus delimited by its internal contour 24 which extends between the first section 28 and the second section 30.

In the first case illustrated in FIG. 4a, the two sections 28, 30 which border the secondary opening 20 of the wedging washer 12 are strictly superimposed, so that the internal contour 24 determines guiding of the lubricant in a direction perpendicular to the first face 16 and / or the second face 18.

In the second case illustrated in FIGS. 4b, the two sections 28, 30 of the secondary opening 20 of the setting washer 12 are offset radially relative to the central axis O. The internal contour 24 delimits the path taken by the lubricant but that follows a direction which is inclined with respect to this central axis O. It can therefore be considered that the secondary openings 20 shown here are at an angle with respect to the central axis O. The setting washer 12 thus comprises at least one opening secondary 20 delimited, so by at least one internal contour which extends between the first section 16 and the second section 18 in a direction oblique to the central axis O, forming an inclined lubricant path.

The third and fourth cases illustrated respectively in FIGS. 4c and 4d show a wedging washer 12 having at least one secondary opening 20, comprising a first section 28 taken in the first plane P of the first face 16, different from the second section 30 associated taken in the second plane P 'of the second face 18 of the setting washer 12.

More specifically, the third case illustrates a first section 28 greater than the second section 30 of the wedging washer 12. Conversely, the fourth case shows a wedging washer 12 having a first section 28 smaller than the second section 30 of the opening secondary 20 associated. Such arrangements make it possible to easily control the quantity of lubricant that the setting washer 12 allows to migrate towards the rotation bearing 6. These arrangements also make it possible to concentrate the lubricant at a particular point in the friction zone 9, or else widen the contacting of the lubricant with the rotation bearing 6, more particularly with the bearing 7.

The electric motor 2, comprising at least one setting washer 12 as described above, has a particular configuration improving the distribution and distribution of the lubricant inside the rear rotation bearing 6, thereby extending the duration of life of a motor starter with high frequency of use.

It will be noted that the invention can also be used for a thermal engine starter of a motor vehicle devoid of the "Stop-Start" function.

Claims (12)

1. Electric motor (2) comprising a motor shaft (4) kept rotating by at least one rotation bearing (6), an axial locking means (8) of the motor shaft (4) with respect to the rotation bearing, a cap (11) delimiting a reserve (10) of lubricant intended to lubricate the rotation bearing (6), and a shim washer (12) interposed between the reserve (10) and the rotation bearing (6 ) and arranged so that the lubricant migrates from a first face (16) of the shim washer (12) to a second face (18) of the shim washer (12), the shim washer (12) having an opening central (14) through which the drive shaft (4) passes, characterized in that the shim washer (12) comprises at least one secondary opening (20). 2. Electric motor (2) according to the preceding claim, characterized in that the secondary opening (20) opens into the central opening (14) of the setting washer (12). 3. Electric motor (2) according to any one of the preceding claims, characterized in that the secondary opening (20) is delimited by a first contour (24) in the form of an arc of a circle and / or of segments of right. 4. Electric motor (2) according to any one of the preceding claims, characterized in that the setting washer (12) comprises three secondary openings (20) angularly distributed around a central axis (O) of the central opening (14), at the periphery of an internal edge (22) of the wedging washer (12) which delimits the central opening (14). 5. Electric motor (2) according to the preceding claim, characterized in that each secondary opening (20) is angularly arranged at 120 ° from one another around the central axis (O). 6. Electric motor (2) according to any one of the preceding claims, characterized in that a ratio between an internal radius (RI) corresponding to the radius of the central opening (14) and an external radius (R2) of the shim washer (12) is between 0.5 and 2. 7. Electric motor (2) according to any one of the preceding claims, characterized in that a ratio between at least one maximum dimension (pl) of the secondary opening (20) and an external radius (R2) of the washer setting (12) is between 0.1 and 0.8. 8. Electric motor (2) according to any one of the preceding claims, characterized in that the secondary opening (20) is delimited by at least one internal contour (24) which extends perpendicularly to one and / or the other of the faces delimiting the setting washer (12). 9. Electric motor (2) according to any one of claims 1 to 8, characterized in that the secondary opening (20) is delimited by at least one internal contour (24) which extends along a direction which forms with one and / or the other of the faces delimiting the setting washer (12) an angle between 25 ° and 85 °. 10. Electric motor (2) according to any one of the preceding claims, characterized in that a first section (28) of the secondary opening (20) taken in a first plane (P) of the first face (16) is equal to a second section (30) of the secondary opening (20) taken in a second plane (P ') of the second face (18). 11. Electric motor (2) according to any one of claims 1 to 9, characterized in that a first section (28) of the secondary opening (20) taken in a first plane (P) of the first face ( 16) is different from a second section (30) of the secondary opening (20) taken in a second plane (P ') of the second face (18). 12. Starter for a thermal engine of a motor vehicle, comprising an electric motor according to any one of claims MFR1139 1/2