EP1222674B1 - Coil frame ignition switch for motor vehicle and ignition switch equipped with same - Google Patents

Description

The invention relates to a carcass contactor for a motor vehicle starter and a starter equipped with such a contactor.

As is known, a contactor for a motor vehicle starter comprises a movable contact capable of being displaced in translation between a rest position, in which the contact bears against a fixed conductive element connected to a polar mass of the vehicle. , and an active position, in which the movable contact establishes the electrical connection between a current input terminal and a power supply terminal of the starter motor. In the active position the shaft of the electric motor rotates a launcher with a pinion, which meshes with a starter ring, rotatably connected to the engine of the vehicle, to start said engine. The input and output terminals are carried by a hollow-shaped support block forming a cover made of insulating material. Such a contactor is described in EP-A-0 768 695.

The contactor comprises a winding with at least one winding for controlling the displacement of a movable core of the contactor, displacement which has the consequence, on the one hand, of causing at the end of the race the power supply of the electric motor of the starter and, d on the other hand, to cause, via a pivoting fork hitched to the movable core and engaging with the launcher, the movement of the starter gear for meshing with the toothed starting ring gear.

Figure 1 shows such a contactor. In this figure for simplicity only the main elements belonging to the state of the art have been referenced. Thus this contactor comprises a carcass 1 of magnetic material, conventionally made of solid soft iron or sintered. This carcass visible only in FIG. 2 forms a cylindrical casing 1 sealingly closed by the cover 6. The annular winding 4 with one or two windings is mounted in this casing 1, which, in combination with the cover 6, protects the interior of the contactor vis-à-vis the external aggressions and which ensures a return to the mass. The annular winding 4, when traversed by an excitation current, causes in the contactor an axial magnetic flux, in particular thanks to a polar mass 2 forming a fixed core and mounted at one of the axial ends of the winding 4. The winding 4 is then capable of causing the axial displacement of the mobile core 3 of magnetic material just like the fixed core 2.

The movable core 3 is thus capable of sliding between a rear rest position in which it protrudes axially through a first axial end of the contactor casing, and an active front position in which, under the effect of the induced magnetic field. by the winding 4, it is almost entirely received inside the winding 4.

The first axial end is formed by the bottom 1a centrally perforated of the carcass 1, which comprises a tubular portion 1b of axial orientation connecting to the outer periphery of the bottom 1a of transverse orientation.

A helical compression spring resiliently removes the movable core towards its rest position by resting on the outer rear face of the bottom 1a facing away from the winding 4. This bottom 1a also serves, thanks to its central opening, to support to a guide tube also carried by the winding support 4. The guide tube is at its inner periphery in intimate contact with the outer periphery of the movable core 3 of cylindrical shape. This core is centrally provided with a blind hole for housing an actuating rod and a tooth against tooth spring acting between the movable core 3 and a head of the rod protruding from the movable core to carry a hinge axis for the starter fork engaged with the starter of the starter.

The carcass 1 is closed at its second axial end opposite its bottom 1a by the cover 6.

The support block 6 comprises a cylindrical annular skirt, which allows its centering and attachment to the second open end of the carcass 1, and a transverse bottom which axially closes the contactor.

Advantageously, the support is made of plastic.

The terminals are substantially diametrically opposed on the bottom of the cover 6, on either side of the axis of axial symmetry of the contactor.

The terminals each comprise a contact head arranged inside the contactor, against the transverse bottom of the support block 6, and a connection pad partially threaded and which extends axially through the transverse bottom so as to open at the bottom. outside the contactor.

The first terminal is intended to be connected to the positive terminal (not shown) of a battery of the vehicle via a switch usually actuated by the ignition key or by any other means. The second terminal is provided to receive a power cable (not shown) of the starter motor.

The support block 6 is fixed, by sealed crimping, to the second end of the carcass 1. To do this carcass 1 has at its second end, constituted by the free end of its tubular portion 1b, a transverse shoulder 1c for support fixed core 2, a cylindrical centering portion of the fixed core 2 and a cylindrical portion 1d of small thickness, said crimping portion, for fixing by crimping the cover 6. More precisely the end of the portion 1d is folded into 6a (Figure 1) inwardly in contact with an outer portion of frustoconical shape of the cover 6 for clamping the fixed core 2 between the shoulder 1c and the free end of the cover 6. The portion 1d of axial orientation s extends axially, in the opposite direction to the bottom 1a, beyond the shoulder 1c.

A movable contact 5, consisting of a plate, is capable of being displaced axially inside the space delimited by the annular wall and the bottom of the cover 6, between a rear rest position in which it bears against the fixed core 2 and an active front position in which the movable contact 5 bears simultaneously against the terminal heads so as to establish between these two terminals an electrical connection which allows powering the starter motor with electrical power from the vehicle's accumulator battery.

The axial displacement of the movable contact 5 is controlled by a control rod, which is guided axially, and whose displacements are controlled by the movable core 3.

In known manner, the movable contact 5 is slidably mounted on the control rod.

The control rod causes the movable contact from its rest position to its active position by means of a contact spring which is supported on one side against a shoulder of the control rod and on the other side against the rear transverse face of the movable contact 5.

A return spring makes it possible to return the control rod and the movable contact 5 to the rest position.

The return spring is supported at the bottom of a cylindrical housing arranged at the center of the transverse bottom of the cover 6 and it axially urges a metal washer (not visible) which bears against a second shoulder of the control rod and against the front transverse face of the movable contact, which also cooperates with the terminals.

In the rest position the movable contact in one embodiment comes into contact with the fixed core 2 advantageously provided with protuberances for this purpose.

It is interesting to use electronic circuits for controlling the power supply of the winding of the contactor. Such electronic circuits make it possible to have perfect control over the displacement of the moving core of the contactor. Thus the contactor is here electronically and comprises a printed circuit board carrying electronic components and which extends in a transverse plane and axially between the fixed core 2 and a transverse wall belonging to a sealing partition. as described in the documents EP A 0 751 545 and the application FR 99 09977 filed on July 30, 1999. Advantageously, the sealing partition is made by molding in plastic material thus allowing for force insertion into the cover 6 advantageously made of the same material. The seal is obtained by the deformation of the material.

Thus, the control rod, which connects the movable magnetic core 3 to the movable contact 5, passes axially through a tubular axial shaft of the sealing wall.

The axial shaft is stepped in diameter and has a front and rear section as described in the application FR 99 09977.

The rear axial annular section is intended to be received inside the bore of the fixed core with which it cooperates sealingly.

A metal connection can be inserted into the bulkhead. The metal connection provides electrical contact between the fixed core 2 and the movable contact 5 when in the rest position.

This connection comprises a tab which protrudes axially towards the front of the partition and which is folded radially so as to extend along the transverse front face of the partition to ensure electrical contact with the moving contact 5 when the latter is in the rest position. This tongue is integral with a washer-shaped base axially traversed by the rear axial annular section of the barrel of the partition. The base ensures electrical contact with the fixed core 2. For this purpose the barrel has a hole for the passage of the tongue. This hole is formed in the shoulder formed by the change of diameter between the rear and front sections of the shaft of the partition. For more details, see the aforementioned application FR 99 09977.

The mobile contact in the rest position is therefore according to the embodiments in contact with either the fixed core, in particular when there is no electronic card inside the contactor, or with a sealing partition. directly or indirectly via a part in electrical contact with the fixed core.

It follows from the foregoing that the thicknesses of the bottom 1a and the tubular portion 1b of the carcass 1 are determined according to the needs of the passage of the magnetic flux. In practice to avoid too much current consumption and too much copper volume at the winding 4, it is necessary not to saturate too much the magnetic circuit, so to have a sufficiently large magnetic flux passage section.

The bottom 1a thus has a relatively large thickness of the order of 3 to 6 mm. The thickness of the tubular portion 1b is lower because the passage section of the magnetic flux is distributed over a larger circumference. This thickness is of the order of 2 to 4 mm. These thicknesses correspond to a manufacture of the carcass by deep drawing of a sheet.

The crimping portion 1d usually has a thickness of 0.4 mm to 1 mm; the tubular portion 1b internally having three different diameters for including formation of the shoulder 1c in favor of a change in diameter.

The carcass 1 is made in a first step by stamping, then in a second operation is the object of machining resumption operations and finally undergoes in a third step a surface treatment to provide protection against corrosion and give a good appearance to this carcass visible from the outside, especially when the starter is mounted on a vehicle.

The machining resumption operations are necessary because, on the one hand, it is necessary to make a length of the carcass 1, and on the other hand, to achieve internal diameters of the tubular portion 1b for formation of the shoulder 1c and the crimping portion 1d.

The surface treatment must be a good conductor of electricity because the external face of the bottom 1a (the rear face) serves to return the earth of the winding 4, which carries out a function of holding the moving contact after closing thereof when the electric motor of the starter rotates, and in the case of an electronically controlled contactor back to earth of the electronic circuit. For the record, note that the bottom 1a is used for fixing the contactor on the housing of the starter.

These three stages require heavy investments, particularly with regard to the deep drawing operation and are rarely carried out in the same geographical location, especially in view of their difference.

It is therefore an object of the invention to provide the carcass more simply and economically.

According to the invention a contactor provided with a carcass made of magnetic material of the type indicated above is characterized in that the carcass is made in three pieces, namely a first piece of transverse orientation, called the bottom, constituting the perforated bottom, a an axially oriented outer tube having the crimping portion and an axially oriented inner tube housed inside the outer tube and in that the outer tube is fixed to the bottom and extends in the opposite direction to the bottom, projecting axially relative to the inner tube having the shoulder.

Advantageously, the inner tube is in contact with the bottom and with the outer tube.

Thanks to the invention each of the elementary components requires only simple and inexpensive means of production.

Compared with a solution by deep drawing of a sheet, requiring a particular metallurgical quality of the sheet, the cost of the material is reduced.

Compared with a solution for obtaining the carcass by extrusion, the investments are reduced.

In addition, the thickness of the bottom can easily be increased.

The outer tube advantageously undergoes in advance the surface treatment operation. The inner tube is protected and does not need surface treatment as it is surrounded by the longer outer tube. This inner tube is housed fixing in the inner tube advantageously by fitting.

The bottom does not need to undergo an aesthetic surface treatment because it is less visible than the external tube made aesthetic, including color and appearance point of view, by its surface treatment also suitable for corrosion resistance. This surface treatment of the outer tube does not have to take into account a good conduction of the electricity produced by the protected inner tube, so that there is a greater number of choices as regards the surface treatment of the outer tube.

In addition, since the bottom is in contact with the starter housing, carrying the electric motor and the contactor, it is possible to do without a surface treatment of the bottom because the risk of corrosion is low because the starter housing is in aluminum alloy. In the case where the starter is subjected to a more aggressive environment from the point of view of corrosion and / or protection is required we choose the nature of the treatment that is best without aesthetic concern.

Of course, the thickness of the inner tube increased by the thickness of the outer tube is chosen to correspond to the thickness of the tubular portion of FIG. 2 and the thickness of the outer tube corresponds to the thickness of the crimping portion of FIG. Figure 2.

This outer tube, of smaller thickness than the inner tube, is cut to the desired length to have the desired length for the crimping portion.

This arrangement facilitates the standardization of the inner tube because the contactor can be electronically or not, which affects the length of the cover and the crimping portion. The outer tube is therefore a piece of adaptation to this variation in length and exceeds more or less of the inner tube to vary the length of the crimping portion according to the applications, which reduces the number of reference parts to store .

The inner tube strengthens the passage section of the magnetic flux and conducts electricity.

The means of production can be brought together in the same geographical location, thereby reducing the additional costs of transport and production management.

In addition no machining recovery operation is necessary since the inner tube has the shoulder and the outer tube the crimping portion. No deep stamping of parts is necessary.

Advantageously, the outer tube covers at least part of the outer periphery of the bottom, which may not be visible and serves as a centralizer to the outer tube.

This arrangement facilitates the attachment of the outer tube with the bottom because it allows a prior centering of these parts.

The first piece constituting the bottom consists of an embodiment in a simple washer. Alternatively the bottom is rectangular, square or polygonal. This is made possible because one can easily give a complementary shape to the relevant end of the outer tube or even to the entire outer tube. The inner tube easily having a shape complementary to that of the outer tube, it follows that the section of the tubes can be circular, rectangular, square, polygonal or other.

Fixing the outer tube with its bottom is advantageously carried out inside the outer tube and thus the carcass to protect this fixation and for aesthetic reasons.

In one embodiment, the bottom and the outer tube are assembled, that is to say fixed to each other, by indirect heat supply, in particular by laser or electron beam welding, which allows a very high degree of heating. located not affecting the outer periphery of the outer tube when this welding is performed inside the carcass. In addition no metal supply is necessary and we obtain a solid fixation, waterproof with good continuity of the magnetic circuit and without protrusion of the weld bead.

This welding is advantageously performed from inside the outer tube with an oblique shot directed towards the outer periphery of the bottom.

The invention also proposes a starter according to the teachings of the invention.

• la figure 1 représente un contacteur selon l'état de la technique qui est illustré en section axiale ;
• la figure 2 est une vue en coupe axiale de la carcasse de la figure 1 ;
• la figure 3 est une vue en coupe axiale de la carcasse selon l'invention ;
• la figure 4 est une vue à plus grande échelle de l'encart IV de la figure 3 avant montage du tube interne.

Other features and advantages of the invention will appear on reading the detailed description which follows for the understanding of which will be attached to the drawings in which:

• Figure 1 shows a contactor according to the state of the art which is illustrated in axial section;
• Figure 2 is an axial sectional view of the carcass of Figure 1;
• Figure 3 is an axial sectional view of the carcass according to the invention;
• Figure 4 is an enlarged view of the inset IV of Figure 3 before mounting the inner tube.

The cylindrical carcass of FIG. 3 is intended to replace the carcass of FIGS. 1 and 2. This carcass, of axis of axial symmetry AA, thus allows a passage of the magnetic flux like that of FIG. 1 and comprises parts made of magnetic material each of simple and economic form.

More precisely according to the invention, the carcass 1 is made in three pieces, namely a first part 12 of transverse orientation, called the bottom, constituting the perforated bottom, an outer tube 13 of axial orientation having the crimping portion 13 'and a internal tube 14, axially oriented, housed inside the outer tube 13. This inner tube 14 has the shoulder 14 'for the fixed core 2 and is here in contact with the bottom 12 and with the outer tube 13 of smaller thickness than the inner tube 14. The thickness of the bottom 12 and therefore the first part is greater than that of the tubes 13,14.

These three parts 12,13,14 are here made of sheet steel based on mild steel. In this figure, the tubes 13, 14 are of constant thickness and have a section of circular shape.

The outer tube 13 is fixed on the bottom 12 and extends in axial projection relative to the inner tube 14 having the shoulder 14 'and in the opposite direction to the bottom 12'.

The bottom 12 replaces the bottom 1a of FIG. 1 and is thus hole here centrally for the passage of the movable core 3. This bottom 12 has the same thickness as the bottom 1a and here consists of a simple washer 12.

The sum of the thicknesses of the tubes 13 and 14 is equal to the thickness of the tubular part 1b of FIG.

The thickness of the outer tube 13 is equal to that of the portion 1d to be able to perform the crimping.

The inner diameter of the inner tube 14 is equal to that of the tubular portion 1b. This tube 14 is supported on the bottom 12 by its first axial end. Its second axial end constitutes the shoulder 14 'for axial support of the fixed core 2. The length of this tube 14 is therefore determined accordingly. Here the outer tube 13 has a first end 13 ', which extends, in the opposite direction to the bottom 12, projecting axially relative to the shoulder 14' and the tube 14 to form the portion 13 'of cylindrical crimping. The tube 14 is also in contact by its outer periphery with the inner periphery of the outer tube 13 and is intended to provide an electrical connection between the bottom 12 and the fixed core 2. The tube 14 is protected by the outer tube 13 longer.

The outer tube 13 is set to length to have the same axial length as that of the carcass of Figures 1, 2 and therefore to have the same axial position for the free ends of the crimping portions 1d, 13 '.

This outer tube 13 is intended, via the inner periphery of its cylindrical crimping portion 13 ', to serve as centering the fixed core. This arrangement simplifies the carcass, which thus has only two diameters internally and does not involve machining operations. additional. The length of the portion 13 'is greater than the portion 1b. Of course the outer diameter of the fixed core is increased in this case.

The outer tube 13 surrounds and thus covers at least part of the bottom 12. Here the tube 13 is in contact by the inner periphery of its other axial end 13 '' with the outer periphery of the bottom 12 so that the bottom 12 is masked by the tube 13, which undergoes in advance a surface treatment to give it an aesthetic appearance and to resist corrosion. The possibilities of choice of this treatment in terms of quality and cost are much greater than those of the carcass of FIG. 2 because this treatment does not have to be a good conductor of electricity.

The bottom may not undergo a surface treatment because it is intended to come into contact with the housing of the aluminum-based starter and not prone to corrosion. However, in severe climatic conditions of use the bottom may undergo a surface treatment that is best without aesthetic concern.

The tube 14 does not need surface treatment because it is housed in the tube 13.

No post-assembly processing of parts 12,13,14 is necessary.

This assembly is achieved by first fixing the end 13 '' of the outer tube to the bottom 12, then simply by engaging the tube 14 in the outer tube 13 until abutting the tube 14 against the bottom 12.

This fitting is advantageously achieved with tightening, here a slight tightening because after crimping the cover 6 the tube 14 is clamped axially between the bottom and the free end of the cover 6 which helps to prevent it from rotating. The value of the tightening therefore depends on the applications. The tube 14 is housed in fixing in the tube 13 so as not to get lost and constitute a carcass manipulable and transportable before mounting the other components of the contactor.

Fixing the tube 13 with the bottom 12 is facilitated by the adjacent end 13 "of the tube 13 covering at least partly the outer periphery of the bottom 12.

In the case where congestion issues do not arise can increase slightly the diameter of the bottom 1 and the end 13 'for forming a shoulder in the tube 13 at the diameter change between the end 13 '' and the main part of the tube 13. In this case it is possible to lengthen the end 13 "and fold it down in contact with the rear face of the bottom in contact with its front face with said shoulder. 13 is thus made in one embodiment by crimping, if necessary at least one welding point can be made between the rear face of the bottom 12 and the folded portion of the end 13 '' to avoid any relative rotation between them. parts 12,13.

In Figure 3 the fixing is performed from the inside of the outer tube 13 and thus the carcass at the outer periphery of the front face of the bottom 12 for particular aesthetic appearance and protect the binding against external aggression. In this figure it does not increase the size and the tubes 13,14 have a simple shape.

Fixing is carried out locally by indirect heat input here by a clean welding of the laser or electron beam type. The energy densities used in this type of welding are very high so that the surface treatments are destroyed in the welding zone and do not interfere with the welding. The heating is very localized and does not affect the surface treatments of the rest of the part concerned in particular the outer periphery of the outer tube 13, which thus retains its aesthetic appearance.

Said weld is made from the inside of the outer tube 13 and therefore the carcass at the outer periphery of the front face of the bottom 12 and the adjacent inner periphery of the end 13 '' of the tube 13 with an oblique shot following the arrow F of Figure 4.

The inner tube 14 consists of a tube section or alternatively a sleeve rolled and welded or rolled and stapled. This tube serves to reinforce the passage section of the magnetic flux also passing through the bottom 12.

The outer tube 13 also consists of a pipe section or alternatively a sleeve rolled and welded or rolled and stapled.

The contactor equipped with the carcass according to the invention mounts in the embodiment shown on a motor vehicle starter.

Of course, the present invention is not limited to the embodiments described. Thus it is possible to further increase the thickness of the bottom 12, which can easily have a thickness of 1.3 to 2 times the sum of the thicknesses of the tubes 13,14. Other fixing means may be envisaged for the tubes 13, 14. For example, the tube 14 can be fixed by oblique shot welding at the bottom 12 in the same manner as the tube 13. In general, it is desired to make the tube 14 captive to form a carcass that can be handled and transported.

As a variant, the fixing of the tube 13 is carried out by axial welding, for example by indirect heat input such as laser or electron beam welding, at the rear face of the bottom 12 between the outer and inner peripheries. respectively of the bottom 12 and the adjacent end 13 "of the tube 13. This type of weld can be made radially between two transverse faces respectively of the bottom 12 and the adjacent end 13" of the tube 13. In this case the bottom has advantageously a plug shape with a shouldered head delimiting the relevant transverse face of the bottom and a body penetrating into the tube 13 by being in contact with a portion of the inner periphery of the end 13 "whose end portion constitutes the other face cross. In a variant, the radial welding is performed between the edge of the end 13 "and the outer periphery of the front face of the bottom 12 so that the outer tube 13 does not cover the bottom 12. In this variant the outer diameters of the outer tube 13 and the bottom 12 are equal.

Advantageously, in all cases, the weld seams are continuous for good bottom sealing, good continuity of the magnetic circuit and good bonding between the parts. It is preferable to use a weld without adding metal to maintain the dimensions of the carcass and to avoid a protuberance of the weld. The welding of the laser or electron beam type, generally by indirect heat input, is well suited for this purpose.

As a variant, the inner tube 14 may advantageously have a diameter change at the level of the shoulder 14 'for centering the fixed core 2 as in FIG. 1 so that the fixed core 2 of FIG. not modified. When congestion conditions, especially axial, do not arise the outer tube 13 may cover the outer periphery of the bottom 12 and extend in axial projection relative to the rear face of the bottom 12. The attachment between the bottom 12 and the outer tube 13 is then made by welding the inside of the tube 13 with an oblique shot as in Figure 3 between in this case the outer periphery of the rear face of the bottom 12 and the adjacent inner periphery of the end 13 ' .

Claims (12)

1. Contactor for a motor vehicle starter, of the type comprising a casing (1) made of material which permits passage of magnetic flow, and comprising a perforated base for passage of a mobile core (3), a shoulder to support a fixed core (2) and a cylindrical axial orientation portion known as the crimping portion, which extends, in the direction opposite the base, axially beyond the shoulder for securing by crimping of a cap (6), characterised in that the casing (1) is produced in three parts, i.e. a first part (12) with transverse orientation, known as the base, which constitutes the perforated base, an outer axial orientation tube (13) which contains the crimping portion (13') and an inner axial orientation tube (14) which is accommodated inside the outer tube (13), and in that the outer tube (13) is secured to the base (12) and extends, in the direction opposite the base (12), projecting axially relative to the inner tube (14) which contains the shoulder (14').
2. Contactor according to claim 1, characterised in that the inner tube (14) is accommodated such as to be secured in the outer tube (13) - base (12) assembly.
3. Contactor according to claim 1 or claim 2, characterised in that the inner tube (14) is crimped into the outer tube (13).
4. Contactor according to any one of the preceding claims, characterised in that the inner tube (14) is in contact with the base (12) and with the outer tube (13).
5. Contactor according to any one of the preceding claims, characterised in that the outer tube (13) covers at least partly the outer periphery of the base (12).
6. Contactor according to any one of the preceding claims, characterised in that the base (12) and the outer tube (13) are secured to one another by means of indirect supply of heat, such as welding of the laser or electron beam type.
7. Contactor according to any one of the preceding claims, characterised in that the base (12) and the outer tube (13) are secured to one another from the interior of the outer tube (13).
8. Contactor according to the preceding claim, characterised in that the securing is carried out by welding of the laser or electron beam type with an oblique shot which is directed towards the outer periphery of the base (12).
9. Contactor according to any one of the preceding claims, characterised in that the outer tube (13) has surface treatment to protect against corrosion and for aesthetic purposes.
10. Contactor according to any one of the preceding claims, characterised in that the outer tube (13) is thinner than the inner tube (14).
11. Contactor according to any one of the preceding claims, characterised in that the thickness of the base (12) is greater than that of the inner (14) and outer (13) tubes.
12. Motor vehicle starter, characterised in that it comprises a contactor according to any one of the preceding claims.

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