EP0068908B1 - Method for the mechanical and electrical connection of conductors to the collector of an armature of an electric machine - Google Patents

Description

The invention relates to a method for making the mechanical and electrical connection of conductors with the collector of an armature of an electric machine, collector comprising an insulating body, of molded material, in which are collector blades provided with notches in which are introduced conductors before the operation of connecting said conductors with the collector.

Already known from French patent 1 369 388 a process in which the connection is obtained by application of mechanical pressure and by electrical heating using a working electrode, the part of which comes into contact with the conductors at an inclination , relative to the longitudinal axis of the collector, substantially identical to the inclination of the conductors in the notches.

The Applicant has found that if such a method is used for connecting the conductors with a collector, the insulating body of which has a large volume, with respect to the collector blades, and the indentations of passage of the conductors extending over the entire height of the notches of the collecting blades the mechanical pressure exerted by the entire contact surface of the electrode on the collecting blades and on the conductors caused the quality of the anchoring of the collecting blades to be destroyed in the insulating body and that the fact of reducing this pressure, in order to avoid this destruction, led to an unsatisfactory level of quality of the connection.

The object of the present invention is to remedy this drawback and for this purpose relates to a method for producing a connection of conductors with an armature collector, connection obtained by mechanical pressure and by electric heating using a working electrode. , method in which an electrode is used, the part of which coming into contact with the conductors is shaped so as to have an angle a, relative to the longitudinal direction of the bottom of the notches, the top of the angle a being disposed on the side opposite the body insulating.

This process has the advantage of avoiding the application of too great a pressure on the side where the collector blades are in contact with the insulating body and ensures the quality of the connection by applying the necessary pressure, to obtain this quality. , in an area where the application of this pressure has no destructive effect on the anchoring of the collecting blades in the insulating body.

• La figure 1 est une vue longitudinale, en coupe partielle, d'un collecteur avec les extrémités des conducteurs introduites dans les encoches, l'électrode étant en position de non-travail.
• La figure 2 est une vue du collecteur de la figure 1, l'électrode étant en position de travail.
• La figure 3 est une vue de face partielle du collecteur des figures 1 et 2.
• La figure 4 est une vue en coupe de l'électrode suivant la ligne AA de la figure 2.

The description which follows with reference to the appended drawings will make it easier to understand how the invention can be implemented.

• Figure 1 is a longitudinal view, in partial section, of a collector with the ends of the conductors introduced into the notches, the electrode being in the non-working position.
• Figure 2 is a view of the collector of Figure 1, the electrode being in the working position.
• FIG. 3 is a partial front view of the collector of FIGS. 1 and 2.
• FIG. 4 is a sectional view of the electrode along the line AA in FIG. 2.

The collector according to FIGS. 1, 2 and 3 and according to a particular mode of application of the method of the invention is a collector of the frontal type, the collecting blades 1 of which are obtained by a stamping operation leaving ribs 2, thin, projecting between two consecutive blades, which ribs are removed during a subsequent operation to finish the armature.

The collector comprises an insulating body 3 (see fig. 1 and 2) made of thermosetting material, in which the collecting blades 1 are anchored by means of protrusions 4 obtained by raising the material of the collecting blades, using a cutting tool.

These protuberances 4 provided in the central part of the collecting blades are embedded in the insulating body 3 during the molding operation of said body.

A metal hub 5 secures the manifold to the armature shaft (not shown).

This hub includes an anchoring means 6 also embedded in the insulating body 3 during the molding operation.

The insulating body 3 has at its periphery notches 7 (see fig. 1 and 2) for the passage of the conductors 8, which notches extend over the entire height of the notches 9 (see fig. 1 and 3) in which come house the conductors 8.

The notches 9 are obtained by a milling operation of the collecting blades 1, the bottom 10 of said notches being perpendicular to the face 11 of the collecting blades (see fig. 1 and 2).

In accordance with the method of the invention, the connection of the stripped ends of the conductors 8 and of the collector is carried out using a working electrode 12 (see fig. 1, 2 and 3) movable in translation, of which the part 13 coming into contact with the conductors 8 is shaped so as to have an angle a, relative to the longitudinal direction of the bottom 10 of the notches 9, the top of the angle a being disposed on the side opposite to the insulating body 3.

The electrode 12 is of trapezoidal section (see fig. 4) and is cut in Vee, in front view (see fig. 3).

In a known manner, in particular by French patent 1 369 388, to achieve the connection of the conductors and the collector, mechanical pressure is applied, by means of the electrode 12 on the part of the conductors 8 and the notches 9 of the contact of the face 13 of the electrode 12, an electrically heated electrode and the return to ground of which is ensured, in a conventional manner by an electrode 14 (see fig. 3) applied to one of the collecting blades.

Claims (1)

1. A method for the mechanical and electrical connection of conductors to the commutator of an electric machine armature, which commutator comprises an insulating body (3) which is made from a moulded material and in which there are anchored by means of projections (4) commutator segments (1) provided with notches (9) into which the conductors (8) have previously been introduced, the connection being obtained by the application of pressure and electrical resistance heating by means of a work electrode (12), characterised in that an electrode (12) is used, of which a part (13) which comes into contact with the conductors (8) is formed so as to have an angle a with respect to the longitudinal direction of the base (10) of the notches, the apex of the angle a being disposed on the side opposite to the insulating body (3).

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