FR2605812A1 - Methods for manufacturing and connecting ring-type commutators for rotating machines - Google Patents

Abstract

Method for manufacturing a ring-type commutator for rotating machines, consisting of a body which is insulating with respect to the shaft, made as a single part or in several parts, and is simultaneously sufficiently flexible and strong to withstand the mechanical shocks and percussions from electromagnetic forming; into this body are optionally made longitudinal grooves, for bringing in the connection leads, and other helical grooves, optionally with variable pitch, to increase the contact surfaces and to prevent unscrewing under the action of reaction torques during rotation.

Description

MANUFACTURING METHODS AND CONNECTION OF
COLLECTORS WITH RINGS FOR TOI-RE MACHINES
The present invention relates to three processes arising from one another for the production of rings for collectors intended for rotary electric machines.

 I1 is reminded that a ring collector comprises an insulating body around which are mounted one or more coaxial rings of electrically conductive material, in particular copper.

 The collector is mounted on the shaft of the rotary machine coaxially with the rotor and its rings cooperate with brushes to supply the electrical windings of the rotor, connected to said rings by suitable connections.

 For the manufacture of this type of manifold, in general, we currently start from a single piece of copper, in one piece, in the form of a socket, and the insulating part of plastic is molded.

After overmolding and assembly of the assembly on the shaft of the rotary machine, the metal part is machined so as to be divided into two coaxial conductive tracks separated by an isolation interval so as to finally obtain two separate rings but remaining linked mechanically through the plastic,
Thanks to the implementation of an initially monobloc metal part, the manufacturing process which has just been recalled in outline, facilitates the manipulations carried out before the operation on overmolding such as maintaining for welding the connections in position precise and the positioning of the welded assembly in the mold.

Toutefoi-s this process has some drawbacks - the amount of metal to be used is greater than that actually necessary to form the collective rings due to the need for machining consisting in reducing the say, tre of the initial sleeve in order to separate it into several parts, each part corresponding to a pole, generally 2 parts for 2 poles.

 In this way, it is necessary to use 30 to 50 / c of metal in addition to that actually useful and there is therefore a large loss of material resulting in an increase in the cost of ring collectors.

 The implementation of one-piece metal parts is not always easy and their production can have drawbacks for the final product.

 Thus, for the production of the socket corresponding to the insulation gap between two rings of the definitive collector, it is necessary to carry out a bar turning operation for which obtaining the desired precision is made difficult due to the dimensional variations of the starting metal tube.

 Especially the deburring operation of this inner groove is delicate and there are too often metallic "wires" which join the two rings and which cause any electrical insulation to be lost from one ring to the other.

 In addition, this serious defect is only perceived after the final machining, that is to say after the completion of the entire rotating part of the machine.

 This leads to a heavy economic loss and a serious disruption of the assembly lines.

 These drawbacks can be avoided by applying various methods in which one starts from various individual metal parts each corresponding to one of the coaxial parts of the final collector which is mounted on an insulating support, itself mounted on the axis of the machine. rotating, each ring then being electrically connected to the terminals of the windings.

 With this technique new difficulties appear with the use of increasingly fine connecting wire, 0.2 to 2 mm for example.

 Hence the present invention relating to three points according to the methods of mounting the collector.

Firstly: The collector is manufactured separately and has connection wires which will be connected to those corresponding to the windings after mounting and positioning on the rotor.

Figure 7 illustrates this solution.

On an insulating body C, composed of one or more parts to simplify its manufacture and leave a certain flexibility to this body which will undergo, subsequently, significant shocks, grooved with variable pitch to avoid possible future unscrewing, we will press a ring of a metal B1, in general aluminum, either after having wound the wire on the body, case of B 1, or not case of B 2, see figures 1 and 2, and insert the shims insulating
I 1 and I 2 after passage of the wires C 1 and C 2 including in the grooves made in the axis, according to FIG. 3.

 Depending on the nature of the metals of C 1 C 2 B 1 and B 2, the wire is passed or not under B 1 or B 2.

By magneto forming we apply B 1, B 2 to the body C1 the connections C 1 C 2 priSONnXees or not
In this way, the body C is kept in block if it is made up of several parts.

 Then, if C 1 or C 2 are not trapped under B 1 or B 2, we proceed to their semi-helical winding with variable pitch.

In the end, we come to plate by magneto forming, the rings
D 1 and D 2, usually made of copper or a Cu - AL sandwich with split aluminum if you want to save money and have great ring flexibility, see Figure 4.

 In this way a ring collector is obtained which is mounted on the rotor shaft of the rotary machine, its connections C 1 C 2 connected by traditional means to the windings, welding, pinching, etc. etc.

Second: The collector is manufactured separately up to the stage shown in Figure 2
From this stage, the wires C 1 and C 2 are replaced by the wires coming directly from the windings of the rotating machine without any intermediate connection and the final magneto-forming operations are continued for D 1 and D 2, according to FIG. 5.

 The body can be in one piece or made of several molded pieces or of paper wound and coated with resin, with one or more ribbons allowing complex shapes.

 The last stages of the process can be integrated into the automatic manufacture of rotors for rotating machines.

Third: The collector is manufactured entirely on the machine shaft, and this, automatically, according to Figure 5 again.

For example, the body C this time, consists of coated paper and wound on the shaft E of the rotary machine, or overmolded parts, or multiple parts assembled by gluing or by magneto forming.

 The wires A and B of the windings are brought directly to the body C thus blocked on the shaft, and all the operations previously described are applied to arrive at the final product, according to FIG. 5.

 The advantage of this process is that it can be automated and completely integrated into the automatic manufacture of rotors of rotating machines.

The subject of the invention is
1 / Method for manufacturing ring collectors for rotating machines, consisting of an insulating body with respect to the shaft, in one piece or in several parts, sufficiently flexible and resistant at the same time to withstand the shocks and percussions of magnetoforming, in this body being possibly provided with longitudinal grooves for the supply of connection wires, and other helical grooves with possibly variable pitch to increase the contact surfaces and avoid unscrewing under the action of reaction torques during rotation.

 In this process the body described above is covered for each pole, with an independent metallic layer which above all does not communicate with another pole or any metallic element of the machine to be equipped, this metallic layer being malleable to support the additional energy. due to magnetoforming, applied below or above, that is to say before or after the winding of the connection wires, according to FIG. 3 left part or right part, and the final goal of which is to increase and improve the surface of contact between the connection wires and the sliding rings, in addition to its role of energy absorption.

This metal layer can be applied by simple mechanical pressure or by magnetoforming
In the final phase of the process, the simple sliding rings or sandwiches with internal layers that may be interrupted to reduce the magnetoforming powers to be used, are applied ~ simultaneously or separately on each pole.

 This operation can be carried out simultaneously with the previous one if the connection wires are wound on the first metallic layer, according to case D1 in FIG. 3.

 By this process are obtained ring collectors with connecting wires. They are mounted on the shafts of the machines and their connection wires connected to the corresponding windings.

 2 / Manufacturing process simplifying the previous one and consisting in directly using the wires coming from the windings of the machine after having mounted on the shaft of said machine the simple or composite body described in the previous chapter and with the same purposes, the operation final magnetoforming on the sliding rings themselves simple or composite, takes place in the final position of the assembly on the machine, rotor shaft in this case, as shown in Figure 5.

 3 / Manufacturing process further simplifying the previous two. The body is manufactured directly on the machine shaft, either by overmolding of insulation, or by winding of possibly impregnated ribbon of insulation, for example fine paper and photopolymerizable resin impressed with UV as the constitution of the body, with one or more ribbons to give complex shapes.

 When the body is formed on the tree, the process is repeated according to the process described in the second claim, either directly in place on the machine.

Claims (3)

 1. - Method of manufacturing ring collectors for rotating machines, consisting of an insulating body with respect to the shaft, in one piece or in several parts, sufficiently flexible and resistant at the same time to withstand the shocks and percussions of magnetoforming, possibly provided with longitudinal grooves for the supply of connection wires, and other helical grooves with not possibly variable to increase the contact surfaces and avoid unscrewing under the action of reaction torques during rotation, characterized in that that said body is covered for each pole, with an independent metallic layer not communicating with another pole or any metallic element of the machine to be equipped, this metallic layer being malleable to support the additional energy due to magnetoforming, applied below or above, i.e. before or after winding the connection wires, to increase and improve the contact surface between the connection wires connections and sliding rings, this metal layer being applied by simple mechanical pressure or by magnetoforming, simple sliding rings or sandwiches with internal layers possibly interrupted to reduce the powers of magnetoforming to be used, being applied simultaneously or separately to each pole.  2. - Method according to claim 1, characterized in that one directly uses the son from the windings of the machine after having mounted on the shaft of said machine said body, the final operation of magnetoforming on the sliding rings taking place in the final position of the assembly on the machine.  3 - Process according to claim 2, characterized in that said body is manufactured directly on the machine shaft, either by overmolding of insulation, or by winding insulating tape possibly impregnated, for example thin paper and photopolymerizable resin UV impressed as the body is built.