WO2018015687A1

WO2018015687A1 - Starter switch comprising a sealing device and starter comprising such a switch

Info

Publication number: WO2018015687A1
Application number: PCT/FR2017/052006
Authority: WO
Inventors: Fabrice MARSAC; Christian Tournier; Rami BOUCHOUICHA
Original assignee: Valeo Equipements Electriques Moteur
Priority date: 2016-07-21
Filing date: 2017-07-21
Publication date: 2018-01-25
Also published as: FR3054371A1

Abstract

Starter switch (1) comprising: - a housing (2) with an axis (O) and defining at least one internal space (18), - at least one coil (3) accommodated in the housing (2), - a core (4) translatably movable along the axis (O), the movable core (4) being accommodated in the coil (3), characterised in that the starter switch (1) comprises a sealing device (6) providing a seal between an environment outside the starter switch (1) and the internal space (18) of the starter switch (1), the sealing device (6) being situated radially between the movable core (4) and the housing (2). Said invention is applicable to motor vehicles.

Description

STARTER CONTACTOR COMPRISING A SEALING DEVICE, AND STARTER COMPRISING SUCH A CONTACTOR

The field of the present invention is that of motor vehicle engine starters.

According to a known design, a motor starter contactor, in particular a motor vehicle, comprises a cylindrical housing in which is placed an annular coil which generates a magnetic field under the effect of an electric current passing through it. Depending on the polarization of the coil, the magnetic field thus created exerts an attractive or repulsive force on a cylindrical and at least partly magnetic mobile core. The movable core is mounted in an interior space delimited by the annular coil so as to be able to slide in axial translation to close or open an electrical circuit connected to the starter motor power circuit and to push a pinion in a motor crown via a lever. The starter switch generally operates in a polluted environment and / or comprising dust and particles which, if they are introduced into the interior space of the housing or between the movable core and an inner wall of the interior space, can prevent the movable core to slide freely inside the coil, or to seize it completely. The insertion of impurities inside the interior space is also facilitated by the translation movements back and forth of the movable core during operation of the starter contactor. These translational movements generate a piston effect when the movable core leaves the housing, causing suction of the air surrounding the starter switch, and therefore the dust and surrounding particles.

In order to maintain the ability of the movable core to slide freely in the coil, it is known to protect the movable core by an elastic plastic protective sleeve, the protective sleeve surrounding the movable core. This solution has the disadvantage of limiting, or even preventing, the exit of the air contained in the interior of the contactor when the movable core slides towards the interior space. This incoming translation generates an increase in the pressure inside the protective sleeve, causing in turn a swelling of the sleeve of protection. The swelling of the protective sleeve leads to the occurrence of friction against other elements of the starter switch, causing premature wear and / or tearing of the protective sleeve. In order to solve the premature wear of the protective sleeves, it is known to pierce the protective sleeve to form a vent allowing the evacuation of the air towards the outside of the protective sleeve. This vent is axial.

Firstly, when the movable core leaves the starter switch, the air surrounding the starter contactor and its impurities are always sucked between the movable core and the coil via vent. This is particularly the case when the dimensions vent dimensions are too large compared to the average particle and dust dimensions. Second, if the dimensions of the vent are too small, the increase in pressure during the translation of the movable core to the interior deforms the protective sleeve and causes premature wear, as previously described. In addition, in case of closure of the vent, the air in the interior space can no longer be evacuated to the outside and causes an excessive increase in the air pressure in the interior space. This increase in pressure may prevent the movable core from completing its axial translation in the interior space if the magnetic field generated by the coil does not further compress the air in the interior space. In this case, the mobile core can no longer close the electrical circuit for starting the starter.

It is thus obvious that the solutions provided by the state of the art do not solve the problems identified.

The object of the present invention is therefore to provide a new starter contactor comprising a sealing device limiting or eliminating air exchanges between the outside and the inside of the contactor.

Another object of the invention is to limit the wear of the sealing device. Another object of the invention is to reduce the breakdowns of a starter contactor.

Another object of the invention is to reduce the maintenance costs of a starter contactor.

According to a first aspect of the invention, there is provided a starter contactor comprising:

an axis housing and delimiting at least one interior space,

at least one coil housed in the housing,

a core movable in translation along the axis, the mobile core being housed in the coil,

characterized in that the starter switch comprises a sealing device providing a seal between an environment outside the starter contactor and the interior of the starter contactor, the sealing device being located radially between the movable core and the housing .

Thus, the invention according to its first aspect eliminates the deformation of the sealing device due to the increase of the pressure of the air inside the switch during operation of the starter contactor.

Consequently, the starter contactor according to the first aspect of the invention makes it possible to reduce the breakdowns and the associated maintenance costs: its reliability is therefore improved.

According to one embodiment, the sealing device is delimited radially on the inside by the movable core and radially outwardly by the housing. The internal and external names refer to the contactor axis. In one embodiment, the sealing device is disposed in a box formed in the housing.

Alternatively, the sealing device comprises a lip seal. The seal to lips can be attached to the housing and seal with the mobile core. The lips of the seal are arranged radially inward towards the moving core.

Another feature of the invention is that the starter contactor according to the invention comprises at least one fluid communication means connecting the interior space to a cavity.

The fluidic communication means makes it possible to put in fluidic communication an interior space of the housing and a cavity. This fluidic communication makes it possible to increase the volume of the interior space, which limits the increase of the pressure of the air inside the starter switch. The movable core can therefore slide inside the interior space and act on the movable shaft despite the increase of the pressure of the air inside the starter switch. The fluidic communication means may be formed in the fixed core, radially on an outer peripheral edge of the fixed core, radially on an inner peripheral edge of the fixed core or radially between the inner peripheral edge of the stationary core and the outer peripheral edge of the core. fixed. According to another characteristic of the invention, the starter contactor comprises a movable shaft, the fluidic communication means being formed in the movable shaft. The fluid communication means may be located radially on an outer peripheral edge of the movable shaft or in another part of the movable shaft. Alternatively, the starter contactor comprises a peripheral space formed in a radially peripheral zone between the housing and the coil, the peripheral space being connected to the cavity by a second fluid communication means. The second fluid communication means may be arranged in the fixed core. Alternatively, the starter contactor comprises a third fluid communication means arranged to be able to put in fluid communication the interior space with the environment outside the starter contactor. The third fluid communication means may also be arranged to port fluidic interior space with the interior volume of the mobile core.

According to another characteristic of the invention, the fluid communication means and / or the second fluid communication means and / or the third fluid communication means are or are not linear with the axis.

The fluid communication means and / or the second fluid communication means and / or the third fluid communication means may be arranged by any method or means. More particularly, the fluid communication means and / or the second fluid communication means and / or the third fluid communication means are of the type of a bore.

The fluid communication means and / or the second fluid communication means and / or the third fluid communication means may have a circular, square, rectangular, or any other shape. The width or diameter of their section is provided to allow optimal flow of air between the compartments of the contactor.

The fluid communication means and / or the second fluid communication means and / or the third fluid communication means may take the form of a single conduit, or comprise a plurality of conduits. In the case of a plurality of ducts, the ducts may be angularly distributed regularly or not. The conduits may be identical, or at least one of them may be different from the others. Alternatively, the fluidic communication means may comprise a plurality of ducts starting from the interior space, this plurality of ducts gathering in a single duct coming into the cavity. Alternatively, the fluidic communication means may comprise a single duct extending from the chamber and dividing into a plurality of ducts opening into the interior space. The movable core, or a portion of the movable core, may include an anticorrosive coating. By anticorrosion coating means a coating for limiting or stopping the oxidation of the outer face of the movable core. This coating can be applied by any method known to those skilled in the art. According to a second aspect of the invention, there is provided a starter comprising a starter contactor described in the first aspect of the invention. According to a third aspect of the invention, there is provided a pressure balancing method of a starter contactor according to the first aspect of the invention, the method comprising the following steps:

during displacement of the mobile core in an interior space of the housing, transfer of compressed air located in the interior space to a cavity and a peripheral space around the coils, via fluidic communication means in order to limit the increase of pressure in the interior space; and

during the movement of the mobile core out of the interior space, displacement of the air contained in the cavity and the peripheral space around the coils, towards the interior space via the fluidic communication means.

Other features, details and advantages of the invention will emerge more clearly on reading the description given below as an indication in relation to drawings in which: FIG. 1 is a view in axial section of a contactor starter according to the invention,

FIG. 2 is a sectional perspective view of a starter contactor according to the invention,

FIG. 3 is a view in axial section of a starter contactor according to an alternative embodiment of the invention,

FIG. 4 is an axial sectional view of a starter contactor according to an alternative embodiment of the invention,

- Figure 5 is an axial sectional view of a starter switch according to an alternative embodiment of the invention.

The embodiments which are described below are in no way limiting; it will be possible to imagine variants of the invention comprising only a selection of characteristics described subsequently 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 are combinable with each other if nothing stands in the way of this combination at the technical level. In such a case, mention would be made in the present description.

In the figures, the elements common to several figures retain the same reference.

In the remainder of the description, the axial, radial, external and internal denominations refer to an axis (O) passing through at its center the starter contactor according to the first aspect of the invention. The axial direction corresponds to the axis (O) crossing at their center the mobile core 4, the fixed core 13, the movable shaft 12, the housing 2 and the coil 3, while the radial orientations correspond to concurrent planes, and in particular perpendicular to the axis (O). For the radial directions, the outer or inner denominations are evaluated with respect to the same axis (O), the inner denomination corresponding to an element oriented towards the axis, or closer to the axis with respect to a second element, the external denomination designating a distance from the axis.

The directions mentioned above are also visible in an orthonormal frame Oxy shown in the figures. Figures 1 and 2 show a starter switch 1 according to the invention equipping a motor starter of a vehicle.

The starter contactor 1 comprises (i) a housing 2 housing at least one coil 3, and a movable core 4 in axial translation axis (O), and (ii) a sealing device 6 connected to the movable core 4 and the housing 2, the sealing device 6 being located around the movable core 4, between the movable core 4 and the housing 2.

The casing 2, of generally annular shape and having the axis (O) as the central axis, defines an empty interior space 18, of cylindrical shape. The housing 2 has a first longitudinal end 30 which is formed a hole in which the movable core 4 slides in and out of the housing 2, and a second longitudinal end 31 closed by a cover 14. The coil 3, of annular shape, is housed in the case 2.

In the example of FIG. 1, the interior space 18 is more specifically defined radially on the outside by the coil 3, axially by an axial end of the housing 2 on the one hand and by a fixed core 13, for example of the general shape of a disc, on the other hand. The fixed core 13 is delimited radially outwards by an inner face of the housing 2. The outer peripheral portion of the fixed core 13 is delimited axially on the one hand by the housing 2 and on the other hand by the cover 14, the form of a cylindrical pot, disposed at the axial end of the housing 2 opposite to that which receives the movable core 4.

The movable core 4, of generally cylindrical shape, is actuated by the coil 3. It slides along the axis (O) in the internal space 18 of the coil 3. The movable core 4 comprises a bore radially centered with the axis (O) and extending axially between two ends of the movable core 4. This bore delimits an internal volume 25. In the internal volume 25 is inserted a shaft 10 for controlling a fork (not shown) to position a starter gear (not shown) on a flywheel (not shown). The pinion is rotated by a starter motor, which makes it possible to start the flywheel and start the engine of the vehicle.

Peripherally outside the movable core 4 and on at least a part thereof, a spring 11, for example of helical type, is arranged to exert a repulsive force on the movable core 4, oriented along the axis (O ) and in a direction out of the housing 2. The spring 11 allows to push the movable core 4 out of the inner space 18 in the absence of supply of the coil 3. The spring 11 bears axially on the device of 6, or on the housing 2, on the one hand and on a terminal flange 20 of the mobile core 4 on the other. The end flange 20 has for example the shape of an "S" shaped disc in a transverse plane and as illustrated in FIG. 1. The spring 11 compresses during the translation of the movable core 4 towards the inside of the starter contactor 1, corresponding to a working position of the mobile core 4, and relaxes when the coil 3 is not polarized, then pushing the mobile core 4 out of space internal 18 of the coil 3, thus corresponding to an initial said position of the movable core.

Located between the movable core 4 and the casing 2, the sealing device 6 is delimited radially inside by the movable core 4, radially outwardly through the casing 2, and axially by the casing 2. sealing 6 covers at least a portion of the movable core 4. The sealing device 6 has the general shape of a ring. The sealing device 6 is made of an elastic material capable of withstanding large and / or repeated deformations. By way of non-limiting example, the sealing device 6 is at least partially made of deformable material.

In this embodiment, the sealing device 6 is composed of a lip seal 7, called SPI seal, disposed between the housing 2 and the movable core 4. The lip seal 7 is disposed on the first longitudinal end 30 in a ring-shaped box disposed on the face of the first longitudinal end 30. The dimensions of the box are complementary to those of the lip seal 7, which allows the lip seal 7 to be maintained in the box. The inner diameter of the lip seal 7 is complementary to the outer diameter of the movable core 4. This allows the lip seal 7 not to hinder the sliding of the movable core 4 in and out of the housing 2. A fluid communication means 8 is arranged in the starter switch 1 to connect the interior space 18 with a cavity 19. In the example of Figure 1, the fluid communication means 8 is arranged in the fixed core 13 of the starter switch 1. The means fluidic communication 8 extends from the inner space 18 in the fixed core 13, parallel to the axis (O), to open into the cavity 19.

The cavity 19 is defined radially outwardly by the cover 14, and axially by the cover 14 on the one hand and by the fixed core 13 on the other hand. This fixed core 13 is arranged to separate the interior space 18 of the cavity 19. The cavity 19 can be arranged in a radially central zone 26 and / or a radially peripheral zone 27 inside the starter contactor 1.

In the example of FIG. 1, the fluidic communication means 8 has a section circular. Alternatively, the fluidic communication means 8 may be of square section or of any other form that is useful for carrying out the fluidic communication between the cavity 19 and the interior space 18. According to an example embodiment, the interior space of the housing 2 comprises a peripheral space 21 which is delimited radially on the outside by the casing 2, radially inside by the coil 3, and axially by the fixed core 13, on the one hand and by an axial end of the casing 2, d 'somewhere else. This peripheral space 21 can be connected to the cavity 19 via a second fluid communication means (not shown). For example, the second fluid communication means is arranged in the fixed core 13 of the starter contactor.

The mobile core 4 exerts a translational force on a movable shaft 12 when the movable core 4 enters the housing 2. The movable shaft 12 further comprises an electrical contact 15 between two positions, intended to cooperate with electrical pads 16 for close or open an electrical circuit intended for the power supply of the starter motor. The movable shaft 12 passes through the fixed core 13 at its center.

The cavity 19 houses the electrical contact 15 and the electrical pads 16. The electrical pads 16 are arranged on an inner face of the cover 14.

A helical spring 17 is arranged to push the movable shaft 12 towards the movable core 4 when the coil 3 is not powered. The movable shaft 12 is provided in its central region 23 with a shoulder 24 on which a first axial end of the return spring 17 is supported. A second axial end of the return spring 17 bears on the cover 14.

When the coil 3 is energized, an electromagnetic field attracts the movable core 4 into the inner space 18 of the coil 3. The movable core 4 translates axis (O) towards the inside of the housing 2. When the core mobile 4 sufficiently enters the housing 2, the movable core 4 compresses the spring 11 and simultaneously moves the movable shaft 12 along the same axis (O). The movable shaft 12 will move the electrical contact 15 disposed on the movable shaft 12 to put it in contact with the studs 16. The contact between the electrical contact 15 and the electrical pads 16 will close the starter motor power supply circuit and allow its launch. By the same axis translation movement (O), the movable shaft 12 will compress the return spring 17. When the coil 3 is no longer fed, the spring 11 pushes the movable core 4 out of the interior space 18. The return spring 17 pushes the movable shaft 12 back to its original position.

The displacement of the movable core 4 along the axis (O) towards the inside of the coil 3 will reduce the available volume in the interior space 18. However, the interior space 18 and the cavity 19 communicating via the communication means 8, the volume that will be compressed will be the sum of the volumes of the internal space 18, the cavity 19, the fluid communication means 8 and any void space formed inside the starter contactor 1 in communication fluidic for example such that the peripheral space 21. With this volume provision significantly greater than the volume of the interior space 18, it limits the increase in pressure inside the starter switch 1 while by preventing the entry of particles and dust into the starter switch 1. The increase of the air pressure is not important enough to slow down or block the translation of the mobile core 4, it allows it while acting on the movable shaft 12. This feature allows the contactor to perform its function despite its tightness.

Figure 3 shows an alternative embodiment of a starter switch 1 according to the invention. In the example of Figure 3, the fluid communication means 8 is arranged differently. The other features and elements of the invention are identical or substantially identical to those set forth in the description of the first embodiment. In this exemplary embodiment of the invention, the fixed core 13 comprises two fluidic communication means 8, the two fluid communication means 8 being disposed on the inner peripheral edge of the fixed core 13. The two fluidic communication means 8 are arranged radially opposite each other. They have one essentially circular section.

FIG. 4 shows an alternative embodiment of a starter contactor 1 according to the invention.

In the example of Figure 4, the fluid communication means 8 is arranged differently. The other features and elements of the invention are identical or substantially identical to those set forth in the description of the first embodiment.

In this exemplary embodiment of the invention, the mobile shaft 12 comprises two fluid communication means 8, the two fluid communication means 8 being disposed on the outer peripheral edge of the movable shaft 12. The two fluid communication means 8 are arranged radially opposite each other. They have an essentially circular section.

FIG. 5 shows an exemplary embodiment of the invention of a starter contactor 1 according to the invention. In the example of FIG. 5, the starter contactor 1 according to the invention further comprises fluidic communication means 8 a third fluid communication means 9. The other characteristics and elements of the invention are identical or essentially identical to those set forth in the description of the first embodiment.

The third fluid communication means 9 is arranged in the movable core 4. More particularly, it is arranged in the axial end of the movable core 4 in contact with the interior space 18. The third fluidic communication means 9 is of the type d a bore, of circular or substantially circular section.

This third fluidic communication means 9 connects the interior space 18 of the housing 2 with the internal volume 25 of the movable core 4. This connection has the effect of increasing the available volume inside the starter switch 1, which has the effect of limiting the increase in pressure air inside the contactor and allows not to slow down or block the translational movements of the movable core 4 towards the interior of the interior space 18.

If the examples each reveal an embodiment of the invention, it is also possible to simultaneously implement several embodiments in a single starter contactor 1. A non-limiting example of a possible combination would be to have a means of fluidic communication device 8 disposed in the fixed core 13, an additional fluidic communication means 8 arranged in the movable shaft 12, a second fluid communication means disposed between the peripheral space 21 and the cavity 19 and a third fluid communication means 9 provided in the movable core 4. The invention described above allows a sealing of the starter contactor

1 by means which limits the introduction of particles and dust therein. The interior space 18 is thus particularly well protected during the input and output movements of the mobile core 4 inside the coil 3.

Claims

1. Starter switch (1) comprising:

a housing (2) with axis (O) and delimiting at least one interior space (18),

at least one coil (3) housed in the housing (2),

a mobile core (4) in translation along the axis (O), the mobile core (4) being housed in the coil (3),

characterized in that the starter switch (1) comprises a sealing device (6) sealing between an environment outside the starter contactor (1) and the interior space (18) of the starter contactor (1), the sealing device (6) being located radially between the movable core (4) and the housing (2).

2. Starter contactor (1) according to the preceding claim, characterized in that the sealing device (6) comprises a lip seal (7).

Starter contactor (1) according to the preceding claim, characterized in that the lip seal (7) is fixed on the housing (2) and seals with the movable core (4) ·

4. Starter contactor (1) according to any one of the preceding claims, characterized in that it comprises at least one fluid communication means (8) connecting the inner space (18) to a cavity (19).

5. Starter contactor (1) according to the preceding claim, characterized in that the fluidic communication means (8) is formed in a fixed core (13).

6. Starter contactor (1) according to claim 5, characterized in that the fluidic communication means (8) is located radially on an outer peripheral edge of the fixed core (13).

7. starter contactor (1) according to claim 5, characterized in that the fluidic communication means (8) is located radially on an inner peripheral edge of the fixed core (13).

Starter contactor (1) according to Claim 5, characterized in that the fluidic communication means (8) is located radially between the inner peripheral edge of the fixed core (13) and the outer peripheral edge of the fixed core (13). .

Starter contactor (1) according to one of Claims 4 to 8, characterized in that the starter contactor (1) comprises a movable shaft (12), the fluidic communication means (8) being arranged in the housing. moving shaft (12).

10. starter contactor (1) according to claim 9, characterized in that the fluid communication means (8) is located radially on an outer peripheral edge of the movable shaft (12).

11. Starter contactor (1) according to any one of claims 4 to 10, characterized in that the fluid communication means (8) is collinear with the axis (O).

12. starter contactor (1) according to any one of the preceding claims, characterized in that it comprises a peripheral space (21) formed in a radially peripheral area between the housing (2) and the coil (3), peripheral space (21) being connected to the cavity (19) by a second fluid communication means.

13. Starter contactor (1) according to any one of the preceding claims, characterized in that it comprises a third fluid communication means (9) arranged to put in fluid communication the interior space (18) with an internal volume (25) of the movable core (4).

14. Starter contactor (1) according to any one of the preceding claims, characterized in that at least a portion of the movable core (4) comprises an anticorrosive coating.

15. Starter characterized in that it comprises a starter contactor (1) as defined in any one of the preceding claims.