Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
  • H01H51/00—Electromagnetic relays
  • H01H51/02—Non-polarised relays
  • H01H51/04—Non-polarised relays with single armature; with single set of ganged armatures
  • H01H51/06—Armature is movable between two limit positions of rest and is moved in one direction due to energisation of an electromagnet and after the electromagnet is de-energised is returned by energy stored during the movement in the first direction, e.g. by using a spring, by using a permanent magnet, by gravity
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
  • H01H51/00—Electromagnetic relays
  • H01H51/02—Non-polarised relays
  • H01H51/04—Non-polarised relays with single armature; with single set of ganged armatures
  • H01H51/06—Armature is movable between two limit positions of rest and is moved in one direction due to energisation of an electromagnet and after the electromagnet is de-energised is returned by energy stored during the movement in the first direction, e.g. by using a spring, by using a permanent magnet, by gravity
  • H01H51/065—Relays having a pair of normally open contacts rigidly fixed to a magnetic core movable along the axis of a solenoid, e.g. relays for starting automobiles

Definitions

• the invention relates to an electromagnetic actuator of a starter of a motor vehicle starter, also called starter contactor.
• the invention relates more particularly to a contactor for a motor vehicle starter, of the type comprising a movable magnetic core which moves axially under the effect of a magnetic field created by a winding comprising at least one electrical conductor wound around a body of a coil, and of the type comprising a fixed magnetic core which extends transversely to a front axial end of the winding, of the type in which the fixed core comprises a rear drum which is received axially in the coil and which comprises a bore axial intended to allow the passage of a movable contact rod, and of the type in which the fixed core comprises a front annular disc, which is assembled to the rear barrel, and which is mounted in a cylindrical housing of the contactor.
• the magnetic field created by the electrical conductor wound around the body of the coil of a contactor follows field lines which are substantially axial inside the coil and which have the form of loops closing on them. - same outside the coil.
• the fixed magnetic core is generally a piece of soft iron which ensures the continuity of passage of the magnetic flux between the carcass of the starter and the movable core.
• the field lines close on themselves in the immediate vicinity of the coil, which makes it possible to increase the efficiency of one electromagnet and to reduce the electric power consumed by it.
• fixed magnetic cores used in the manufacture of starters are conventional in one piece, and produced by a conventional extrusion process.
• the thickness of the front disc which is an essential constructive arrangement for providing satisfactory guidance of the movable contact rod linked to the movable core, is such that its cutting with the press imposes low production rates and requires a press of high power, which makes the disc manufacturing before an expensive operation.
• the invention proposes a fixed magnetic core for making a commitment.
• the invention provides a contactor for a motor vehicle starter, of the type comprising a movable magnetic core which moves axially under the effect of a magnetic field created by a winding comprising at least one electrical conductor wound around '' a body of a coil, and of the type comprising a fixed magnetic core which extends transversely to a front axial end of the winding, of the type in which the fixed core comprises a rear drum which is received axially in the coil and which comprises an axial bore intended to allow the passage of a movable contact rod, and of the type in which the fixed core comprises a front annular disc, which is assembled to the rear barrel, and which is mounted in a cylindrical housing of the contactor, characterized in this that the front disc of the core consists of a stack of sheets.
• the sheets are thin sheets cut with the press; the sheets include stapling means to each other, and means for connecting to the rear barrel
• the means for connecting the sheets to the rear barrel comprise a centering hole, formed in each of the sheets, which makes it possible to force-fit the stacking of sheets on a crown belonging to the rear barrel;
• the axial length of the crown is equal to the thickness of the stack of sheets, the front end of the ring flush with the front annular face of the front end sheet;
• the stack of sheets has at least one axial peripheral groove and the front end sheet has a radial tab cut out near the periphery of the front end sheet, so as to receive an electrical ground conductor of the coil and be folded down to mechanically lock the conductor on the front end plate;
• the front end plate has at least two cut lugs which extend axially forward for fixing an electronic card, in particular by soldering or soldering; the front end plate is tinned to facilitate soldering of the electronic card; - The front end plate has on its edge at least three points which extend radially outward, so as to penetrate the material of the cylindrical housing of a carcass of the contactor in which the stack is fitted axially to ensure an electrical contact between the stack of sheets and the carcass.
• Figure 1 is an axial sectional view of a front part of a contactor, representing a fixed core in one piece according to the state of the technical;
• FIG. 2 is an exploded perspective view of a fixed core in two parts according to the state of the art
• FIG. 3 is a view of a fixed core in two parts according to a first embodiment of the invention, shown in axial section in the plane of its peripheral axial grooves;
• FIG. 4 is an exploded perspective view of the fixed core according to Figure 3;
• - Figure 5 is a view of the fixed core according to Figure 4 which is shown in axial section along the plane 5-5 of Figure 4 in the plane of the radial tab of its front end plate;
• FIG. 6 is a view of a fixed core in two parts according to a second embodiment of the invention, the front end plate of which comprises lugs, and which is shown in axial section in the plane 6-6 of Figure 7;
• Figure 7 is an exploded perspective view of the fixed core according to Figure 6, and an associated electronic card; and Figure 8 is a perspective view of a front end plate having spikes, in accordance with a third embodiment of the invention.
• FIG. 1 shows a starter switch 10 (not shown) intended to equip a combustion engine of a motor vehicle.
• the starter switch 10 comprises a substantially cylindrical carcass 12 which comprises from front to back, that is to say from right to left, a bore 14 of large diameter and a bore 16 of small diameter.
• the large diameter bore 14 has at its front end a chamfered inner cylindrical surface 15 whose function will be described later.
• a shoulder surface 18 delimits the two bores 14 and 16.
• the large diameter bore 14 receives a coil 20 which is immobilized axially, along the longitudinal axis XX of the contactor by the shoulder surface 18.
• the coil 20 is substantially cylindrical and has an internal bore 22 of substantially equal diameter to that of the small internal bore 16 of the carcass 12, so that, when the coil 20 is mounted in the carcass 12, the internal bore 22 of the coil 20 is aligned along the axis XX with the small diameter bore 16 of the carcass 12.
• the internal bore of small diameter 16 and the internal bore 22 of the coil receive in axial sliding a movable magnetic core 24.
• the assembly of the coil 20 and the magnetic core 24 form an electromagnet which is capable of controlling the operation of the vehicle starter.
• the detail of the operation of the electromagnet and of the core is part of the state of the art and, as such, will not be developed in the present specification.
• a fixed magnetic core 26 is arranged at the front axial end of the coil 20.
• the fixed magnetic core 26 comprises a rear barrel 28, substantially cylindrical, which is received axially in the internal bore 22 of the coil 20, and a front annular disc 30, which is received in a cylindrical housing 11 at the front of the internal bore 14 of large diameter and formed in the carcass 12.
• the disc 30 is pressed against the front end 32 of the coil 20 by a cover 34.
• the cover 34 is crimped into the chamfered inner cylindrical surface 15 of the carcass 12 and axially closes the internal bore 14 of large diameter of the carcass 12.
• the rear barrel 28 includes, rear towards the front, a rear male frustoconical bearing surface 36 which is intended to be received in a female frustoconical bearing surface complementary to the mobile magnetic core, and a front cylindrical body 41, the female frustoconical bearing surface 38 and the cylindrical body 41 delimiting a surface shoulder 40.
• the shoulder surface 40 is intended to serve as a stop for an annular cylindrical face 42 of the front end of the movable magnetic core 24 during its axial movements.
• the fixed magnetic core 26 is pierced in its center with a hole 44 intended to allow the passage and the guiding of a movable contact rod 46 which is capable of being controlled in its axial displacements by the axial movements of the movable magnetic core 24 to establish, via the contact plate 47 which it carries, an electrical contact between two terminals 48 carried by the cover 34 for closing the carcass 12.
• the fixed magnetic core 26 is in contact with a metallic body 50 of the coil 20.
• the fixed magnetic core 26 is itself made of a magnetic material and advantageously achieves the closing of the magnetic circuit of which the coil 20 is a part, so that, when a current flows through the winding of the coil 20, the field lines inside the coil 20 are substantially axial and parallel to the axis XX.
• the fixed magnetic core is a piece of metallic material magnetic made in one piece as shown in Figure 1.
• the fixed magnetic core is made by extrusion, which, given the complex shapes it includes, such as the frustoconical bearing 36, the surface of shoulder 40, or the hole 44 for passage of the movable contact rod 46, makes it a relatively expensive part to manufacture.
• FIG. 2 represents another state of the art in which the fixed magnetic core 26 is produced in two parts, the rear barrel 28 and the front disc 30 being produced separately.
• the assembly of the rear barrel 28 and of the disc 30 has shapes similar to the fixed magnetic core 26 described previously with reference to FIG. 1.
• the rear barrel 28 comprises, from back to front, the frustoconical bearing 36, the cylindrical body 41 , and a front axial cylindrical crown 54 whose internal diameter corresponds to the diameter of the hole 44 previously described, and whose external diameter, markedly less than that of the cylindrical body 41, is intended to allow centering of the front disc 30 while being received in a hole 56 for centering the front disc 30.
• the front disc 30 can be assembled to the rear drum 28, and the assembly thus forms the fixed magnetic core 26.
• This design makes it possible to produce a fixed magnetic core 26 in two parts, the rear barrel 28 being produced by extrusion, bar turning or sintering, while the front disc 30 is obtained by cutting with the press, which makes it possible to significantly reduce the costs of fabrication of a fixed magnetic core 26 as described.
• the manufacture of the front disc 30 requires, because of its thickness, the use of a high-power hydraulic press and the cutting time of such a front disc 30 is high, and therefore expensive.
• the invention overcomes this disadvantage.
• the fixed magnetic core 26 in two parts shown in Figures 3 to 5 has a rear barrel 28, identical to that described with reference to Figure 2 .
• the front disc 30 is composed of an assembly of thin sheets 32, here four in number, stacked axially on each other, and the stacking of which forms a front disc 30 of general shape similar to that previously described with reference to FIG. 2.
• Each sheet 32 has a centering hole 56, of diameter equal to that of the front disc 30, previously described with reference to FIG. 2, and the stack of sheets 32 has a total thickness which is equal to that of the crown 54 of the rear barrel 28, so that the front annular end 55 of the crown 54 is located in the transverse plane of the front face 33 E of front end plate 32 E of the stack .
• Each sheet 32 can advantageously be cut using a hydraulic press of low power, and in reduced time, which allows to significantly reduce the manufacturing costs.
• the sheets 32 are subsequently linked to each other by staples (not shown) so as to form the front disc 30.
• the stack of sheets 32 which constitutes the front disc 30 has at its periphery two axial grooves 58, diametrically opposite, which are intended to allow the passage of an electrical conductor 60 ground of the coil 20.
• the grooves 58 of the assembly of sheets 32 which form the front disc 30 are obtained by a similar cut made in each of the sheets 32.
• the front end disc 32 E has on its external face 33 E a radial tab 62 which is cut by example by punching in the front end disc 32 E , and which is capable of being spread by folding to allow the electrical ground conductor 60 to pass and then folded axially towards the rear to immobilize it relative to the front disc 30.
• the radial tab 62 guarantees good mechanical resistance of the conductive wire 60 on the front disc 30 by discharging the solder from the electrical ground conductor 60 of the mechanical stresses that would be likely to apply to it.
• FIG. 6 shows a second embodiment of the invention in which the front end plate 32 E of the assembly of plates forming the front disc 30 comprises lugs 64 of substantially axial orientation and turned towards the 'front, so as to allow the fixing by welding or soldering of an electronic card 66.
• the pins 64 are at least two in number, to guarantee a good fixing of the electronic card 66, but this choice is not restrictive and they can be more numerous.
• the manufacture of the fixed magnetic core 26 is similar to that of the fixed magnetic core 26 previously described with reference to FIGS. 3 to 5, the lugs 64 being produced in the same way as the radial tab 62 previously described, that is to say cut, for example by punching, near the periphery of the end sheet 32 E , then folded perpendicularly to the latter in the axial direction XX so that they extend in front of the end sheet 32 E which can then be stapled to the other sheets 32.
• the electronic card 66 associated with the lugs 64 comprises two slots 68, substantially rectangular diametrically opposite, intended to be crossed by the lugs 64 so that these are welded to the electronic card 66.
• the end plate 32 E is tinned during the manufacturing process of the fixed magnetic core 26 to facilitate the welding of the electronic card 66 on the lugs 64.
• the pins 64 of the front end sheet 32 E are aligned radially with the groove 58 formed in the stack of sheets 32, and the electronic card 66 has two holes 70, diametrically opposite and aligned with the slots 68, to allow the passage of the ground conductor 60 of the coil described above.
• ground conductor 60 of the coil can therefore advantageously be soldered directly to the electronic card 66.
• a third embodiment of the invention comprises a magnetic core of general construction similar to the preceding ones which comprises a sheet 32 whose edge 72 comprises four points 74 intended to penetrate the cylindrical housing 11 of the carcass 12, previously described with reference to FIG. 1.
• the tips are four in number, but it suffices that the sheet 32 E comprises at least three and that they are distributed at regular angular intervals.
• the tips 74 penetrate radially and outwards into the material of the carcass 12 to ensure a satisfactory electrical ground contact between the fixed magnetic core 26 and the carcass 12 of the coil.
• the use of a stack of thin sheets makes it possible to produce functional shapes such as the grooves 58, the pins 64 or the tips 74 by an easy manufacturing and implementation process, which allows a significant reduction in production costs.

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• Physics & Mathematics (AREA)
• Electromagnetism (AREA)
• Electromagnets (AREA)
• Connection Of Motors, Electrical Generators, Mechanical Devices, And The Like (AREA)

Priority Applications (5)

Applications Claiming Priority (2)

Publications (1)

Family

ID=9530163

Family Applications (1)

Country Status (8)

Cited By (1)

Families Citing this family (7)

Citations (3)

Family Cites Families (6)

• 1998
  • 1998-09-03 FR FR9811121A patent/FR2783089B1/fr not_active Expired - Lifetime
• 1999
  • 1999-09-03 EP EP99941683A patent/EP1029334B1/fr not_active Expired - Lifetime
  • 1999-09-03 BR BRPI9906759-5A patent/BR9906759B1/pt not_active IP Right Cessation
  • 1999-09-03 KR KR1020007004683A patent/KR100671572B1/ko not_active Expired - Lifetime
  • 1999-09-03 US US09/530,432 patent/US6281770B1/en not_active Expired - Lifetime
  • 1999-09-03 DE DE69933430T patent/DE69933430T2/de not_active Expired - Lifetime
  • 1999-09-03 JP JP2000569415A patent/JP2002524826A/ja active Pending
  • 1999-09-03 WO PCT/FR1999/002100 patent/WO2000014758A1/fr not_active Ceased

Patent Citations (3)

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