FR2747836A1 - STARTER CONTACTOR IN PARTICULAR FOR A MOTOR VEHICLE AND STARTER EQUIPPED WITH SUCH A CONTACTOR - Google Patents

Abstract

The invention provides a starter contactor which comprises contactor coils (18), a fixed core (20) and a movable core (22) on which the fixed core (20) acts when feeding the coils (18). , a movable contact pin (26) capable of being moved by the movable core (22) during its movement, and a movable contact pallet (28) driven by the movable contact pin (26) towards terminals of contactor (30) in order to close a supply circuit of the starter motor, characterized in that the movable contact paddle (28) is associated with an inertia mass (60).

Description

The invention relates to a starter switch in particular

  for a motor vehicle and a starter fitted with such a contactor.

  The invention relates more particularly to a starter contactor which comprises contactor coils, a fixed core and a movable core on which the fixed core acts when the coils are fed, a launcher fork coupled to the movable core, an axis of movable contact capable of being moved axially by the movable core during its displacement, and a movable contact pallet driven by the movable contact axis towards contactor terminals in order to close a supply circuit for the starter motor. With a starter contactor of this type, when the contactor coils are supplied, the movable core magnetically attracted by the fixed core pushes the movable contact axis and closes the motor supply circuit via the pallet mobile. At the same time, the moving core pushes the starter pinion into the starter ring of the heat engine via the fork and a spring called "tooth spring".

against tooth ".

  Because of the inertia of the moving masses and the elasticity of the fork and the spring, there may appear, between the movement of the contact paddle and the movement of the starter pinion, a phase shift such that the electric motor is powered before

  the pinion is not engaged in the starter ring gear.

  This results in very rapid deterioration of the crown

  by the starter pinion and / or the starter teeth.

  To remedy this problem, various solutions are known, which notably consist in slowing down the movement of the mobile core by damping effect or "dash-pot" by compressing the volume of air comprised between the mobile core and the fixed core. The result is limited due to the fact that air leaks at the moving parts are difficult to control. In addition, the obligation to size the sliding parts very precisely, or to use seals, represents delicate solutions to be implemented,

  and they bring a significant additional cost to the starter.

  Other solutions are also known, which consist in implementing electronic systems which make it possible to supply the coils of the contactor with a progressive voltage to avoid too sudden acceleration of the mobile core. These

  solutions also generate additional costs.

  The objective of the present invention is therefore to propose an economical and simple solution for introducing a mechanical delay on closing the contact of the supply circuit of the

starter motor.

  For this purpose, the present invention provides a starter contactor, comprising contactor coils, a fixed core and a movable core on which the fixed core acts during the supply of said coils, a movable contact axis capable of being moved by the movable core during its displacement, and a movable contact pallet driven by the movable contact axis towards contactor terminals in order to close a supply circuit of the starter motor, characterized in that the movable contact pallet associated with a mass of inertia This mass of inertia simply imposes a delay

when the moving contact moves.

  According to other characteristics of the invention - the mass of inertia is made of magnetic material - the mass of inertia is made of magnetic material; - the inertia mass is made of conductive material - the inertia mass receives two contact grains, reported by crimping, soldering, riveting or by screwing, located opposite the contactor terminals; - the mass of inertia is formed by a separate part fixed to the contact pallet; - the inertia mass is fixed to the contact pallet by crimping, screwing, stapling. bonding, welding, or nesting; - the mass of inertia is produced by sintering, striking,

  forging, machining, molding, or stamping.

  The invention also provides a starter equipped with a

  contactor made in accordance with the teachings of the invention.

  Other characteristics and advantages of the invention

  will appear on reading the detailed description which follows, for the

  understanding of which reference will be made to the accompanying drawings, in which: - Figure 1 is a view in partial axial section through a vehicle starter, showing in particular the contactor and the launcher, in accordance with the prior art; - Figure 2 is a detailed axial sectional view which shows the contactor according to the present invention, in the rest position; - Figure 3 is a sectional view similar to those of Figure 2, showing the contactor in an intermediate axial position; - Figure 4 is a sectional view similar to those of Figures 2 and 3, showing the contactor in an active position which closes the supply circuit to the motor; - Figure 5 is a perspective view which shows an embodiment for the mass of inertia associated with the contact paddle, according to the invention; and - Figure 6 is a cross-sectional view of the mass

  of inertia along line 6-6 of Figure 5.

  In the starter 10 illustrated as a whole in FIG. 1, the role of the contactor 12 is on the one hand to move a starter pinion 14 in mesh with the starter ring of the thermal engine of the vehicle (not shown), and, d on the other hand, to close a

  electric supply circuit of the starter motor 16.

  In more detail, the contactor 12 comprises contactor coils 18, a fixed core 20, a movable core 22 on which the fixed core acts, a launcher fork 24 coupled to the movable core 22, a contact axis 26 movable and capable of to be moved by the movable core 22 during its axial displacements, and a movable contact pallet 28 driven by the movable contact axis 26 towards terminals 30 of the contactor in order to close a circuit

  starter motor supply 16.

  The contactor coils 18, the fixed core 20, the movable core 22, and the movable contact pin 26 are arranged coaxially in a contactor housing 32. The arrangement of these elements being well known to those skilled in the art, it is will not describe it

not here in detail.

  For its part, the starter fork 24 is articulated around a transverse axis 34 located between the longitudinal axes of the contactor 12 and the motor shaft 36 of the motor 16 which carries the pinion

launcher 14.

  The coupling between the mobile core 22 and the launcher fork 24 is ensured by means of a rod 38, articulated at one end of the fork 24 and which penetrates axially into the mobile core 22, with the interposition of a spring 40, called "tooth against tooth spring", between an internal shoulder of the movable core 22 and the head 42 of the rod 38. These elements are also well known

  tradesmen and we will not continue their description in

detail.

  In order to cooperate with the movable contact axis 26, the movable core 22 comprises at its corresponding end a push plate 44 situated at a predetermined distance from the movable contact axis 26. The latter passes through a coaxial bore 46 of the fixed core as well as a central bore formed in the contact pallet 28 and its end 47 oriented towards the contactor terminals 30 receives an abutment flange 48 against which a return spring 50 which pushes the contact axis 26 and the contact pallet 28 bearing against the fixed core 20, the other end of the spring 50 bearing axially against the internal face of the cover 51 of the contactor which carries the terminals 30. A spring 52 is interposed between a shoulder 54 of the axis contact 26 and the face of the pallet 28 facing the core

fixed 20.

  Having thus described the elements of a starter with a contactor known from the state of the art, we will now

  briefly describe how it works.

  When it is desired to start the engine of the vehicle (not shown), the contactor coils 18 are electrically supplied, and the magnetic field thus produced axially attracts the movable core 22 to the right. The movement of the mobile core 22 is transmitted by the rod 38 to the fork 24, with the effect of pushing the starter pinion 14 to the left to cause it to mesh with the starter ring (not shown) of the

thermal motor.

  At the same time, the movable core 22 pushes, via its push plate 44, the movable contact axis 26 to the right, which has the effect of moving the contact pallet 28, under the action of the spring 52, in the direction of the contactor terminals 30, thereby closing an electrical power circuit (not shown)

  to power the electric motor 16.

  The driving energy supplied by the electric motor 16 via its output shaft 36 is transmitted to the starter pinion 14 and therefore to the starter ring. For various reasons already mentioned, there may be a certain delay in the movement of the starter pinion 14 towards its engagement in the starter ring, in particular because of the elasticity of the various parts involved in this movement, relative to the movement of the contact rod 26 for closing the electrical circuit via the contact paddle 28. As is easily understood, the rotation of the starter pinion 14 before it meshes with the starter ring quickly causes

  mechanical damage to the pinion and the crown.

  To avoid this phenomenon, the invention provides for associating with the movable pallet 28 a mass of inertia 60, which will now be described.

  in detail with reference to Figures 2 to 6.

  Figures 2 to 4 show in axial section only the part of the contactor, it being understood that the rest of the starter is identical to the representation of Figure 1. Furthermore, the elements identical or similar to those of Figure 1 relate to the other

  figures the same reference figures.

  As shown in FIG. 2, the mass of inertia 60 has on the whole a plate shape, similar to that of the

  contact pallet 28, and it is fixed to the latter.

  The main role of the mass of inertia 60 is to increase the mass of the pallet, and thus to introduce a delay in the movement of the latter in the direction of the contactor terminals 30, and therefore to achieve that the closing of the circuit. electric motor supply 16 does not happen prematurely compared to

  the engagement of the starter pinion 14.

  For convenience, it is preferable that the inertia mass 60 is formed by a separate piece fixed to the contact blade 28, as shown. This fixing can take place by any known process suitable for this purpose, such as in particular by crimping. screwing. stapling, gluing, welding, or nesting. The inertia mass 60 itself is produced, depending on the material envisaged, by sintering, striking, forging, machining, molding or stamping. The process will be chosen according to

  technical and economic parameters.

  As illustrated in FIG. 2, provision is advantageously made for the fixed core 20 to have a recess 62 in its face facing the contact blade 26 and the inertia mass 60, and the inertia mass is at least partially received in this recess 62 which

  locally promotes magnetic leakage from the contactor.

  Provision can be made for the inertial mass 60 made of magnetic material, whereby a magnetic attraction force is obtained against the fixed core 20 which is added to the inertial forces and participates in the momentary holding in the position of rest of

  the movable contact pin 26 and therefore of the contact pallet 28.

  Similarly, provision can be made for the inertial mass 60 to be made of a magnetic material, so as to produce a third holding force in the rest position, which is added to the two forces.

previously cited.

  As a variant, provision may be made for the inertial mass 60 to be fixed to the contact blade 28 on the side of the contactor terminals 30

  and that it itself ensures contact between the terminals.

  To do this, it is then necessary that the mass of inertia is made of conductive material. Such a variant is shown in Figure 5, and in section in Figure 6. The inertia mass 60 in this case has the shape of a transversely elongated plate and it receives two contact grains 64, which are added by crimping , soldering, riveting or by screwing, and which are located opposite the contactor terminals 30. It can even then be envisaged that the contact blade and the inertia mass form a

unique piece.

  Returning to the succession of FIGS. 2 to 4, FIG. 2 shows the contactor in a first state, in which the movable core 22 has moved the distance which separates it at rest from the contact axis 26 and begins to move the latter to the right, that is to say in the direction of the contactor terminals 30. The contact paddle 28 and the inertia mass 60 are again in contact against the fixed core 20, mainly because of the inertial forces acting on the mass of inertia 60 and the pallet 28, but also under the action of possible magnetic forces, when the mass

  inertia 60 is made of magnetic or magnetic material.

  In FIG. 3. the movable core 22 has continued to move to the right until it comes into abutment against the fixed core 20. The movable contact axis 26 is then moved against the return spring 50 until its extreme position to the right. During this movement, it compresses the spring 52 which presses against

  the contact paddle 28 and the mass of inertia 60.

  Due to the inertial forces and possibly the magnetic forces already mentioned, the contact palette and the mass

  of inertia have not yet moved relative to the fixed core.

  The figure shows these elements just at the moment when the force of the spring will overcome the inertial forces and when the pallet 28 with the mass of inertia 60 will begin to move to the right in

  direction of contactor terminals 30.

  Figure 4 shows the same elements a fraction of a second later, after the force exerted by the spring 52 on the contact pallet and the inertia mass 60 is overcome the inertia forces and that the contact pallet with the mass of inertia are moved to the right until it comes into contact against the terminals of

contactor 30.

  It can thus be seen that the closing of the electric supply circuit of the motor 16 occurs with a certain delay, and it is thus ensured that this closing certainly occurs only after the starter pinion 14 has come into operation.

  meshing with the starter ring.

  When the engine is started, the power to the contactor coils 18 is cut off, and the various elements return to their starting position under the action of the various return springs. In particular, the contact pallet 28 and the inertia mass 60 are brought back, together with the contact axis 26, in abutment against the fixed core 20, by the return spring 50, the contact axis 26 being itself - even pushed into abutment against a shoulder

  corresponding to the fixed core 20 by the spring 52.

  For its part, the movable core 22 is pushed back into its starting position, to the left, which also has the effect of bringing the fork 24 and the starter pinion 14 back to their starting positions. The return of the contact pallet 28 also

  for the purpose of interrupting the supply circuit to the motor 16.

  One of the advantages of the invention is to provide an economical and space-saving timing function. This time delay is all the more effective as the mobile core moves quickly, which makes it possible to accommodate larger clearances between the mobile core and the tube which ensures its guidance, requiring less precision on these components, which allows

  savings as to their achievement.

Claims (10)

  1. Starter contactor, comprising contactor coils (18), a fixed core (20) and a movable core (22) on which the fixed core (20) acts when feeding said coils (18), an axis contact pin (26) capable of being moved by the movable core (22) during its movement, and a movable contact pallet (28) driven by the movable contact pin (26) to contactor terminals (30 ) in order to close a starter motor supply circuit (16), characterized in that the movable contact paddle   (28) is associated with a mass of inertia (60).   2. starter switch according to claim 1, characterized in that the fixed core (22) has a recess (62) and in that the inertia mass (60) is at least partially received in the recess (62).   3. Starter switch according to one of the other   Claims 1 and 2, characterized in that the mass of inertia (60)   is made of magnetic material.   4. Starter switch according to any one of   previous claims, characterized in that the mass of inertia   (60) is made of magnetic material.   5. Starter switch according to any one of   previous claims, characterized in that the mass of inertia   (60) is made of conductive material.   6. starter contactor according to claim 5, characterized in that the mass of inertia (60) receives two contact grains (64), reported by crimping, soldering, riveting or by   screwing, located opposite the contactor terminals (30).   7. Starter switch according to any one of   previous claims, characterized in that the mass of inertia   (60) is formed by a separate piece attached to the contact pallet (28). 8. starter contactor according to claim 7, characterized in that the mass of inertia (60) is fixed on the contact pallet (28) by crimping, screwing, stapling, gluing, welding, or by nesting.   9. Starter switch according to any one of   previous claims, characterized in that the mass of inertia   (60) is produced by sintering, striking, forging, machining, molding, or by stamping.   10. Motor vehicle starter, characterized in that it is equipped with a contactor according to any one of previous claims.