US1870713A - Wire coil and method of making same - Google Patents

Description

Aug.9,1932. HDE JONG 1,870,713

' WIRE COIL AND METHOD OF MAKING SAME Filed Feb. 12, 1950 INVENTOR HENDRIK dc JONG I BY MW ATTORNEY 1 Patented Aug. 9, 1932 UNITED STATES PATENT OFFICE HENDRIX DE J'ONG, 0F EINDHOVEN, NETHERLANDS, ASSIGNOB TO RADIO CORPORA- TIONOF AMERICA, A CORPORATION OF DELAWARE WIRE COIL AND METHOD OF MAKING-SAME Application filed February 12, 1930, Serial N0.-f42 7,720, and in the Netherlands February'22, 1929.

The present invention relates to the art of coil winding and more particularly is directed to electrical coils .wherein insulating strips are inserted between adjacent layers.

It is known when winding wire coils to separate the layers of wire windings by layers of a material suitable for that purpose, for example, paper. The latter layers may be applied by slipping elongated strips between the layers of wire windings duringthe operation of winding the wire and winding them on :-the bobbin. The process iscarried out as follows: when a layer of wire windings has been wound and the wire has arrived at the flange ofthe bobbin, the strip is fed and slipped between the wire-and the newly completed layer of wirewindings. Thus the strip is gripped by the wire and wound on the bobbin, whereupon the next layer of wire windings is wound on this coiled strip.

According to the method of the invention the strip before it is wound is provided with at least one bevelled end, after which it is fed so that the sharp point of the bevelled end is adjacent the side where the strip on being wound on the bobbin is gripped by the wire. The advantage of this method consists in that the strip is pulled taut around the coil so that practically no wrinkles can ensue.

When the strips are fed from a supply roller and at the same time out into proper lengths, they may be severed so that the incisions formed are slanting with respect to the longitudinal axis of the strip so thatthe successive incisions zigzag. Thus it is possible to shift the pointed edge of the strip during the winding operation successively towards another flange side of the bobbin.

The coils thus wound have the advantage of being very compact and small because the material of the strip is prevented from wrinkling. Transformer coils, for example, may be wound advantageously in this manner.

In order to assist the winding of coils of small size, strips of unequal length may be wound between the wire windings in such a manner that the larger the diameter of the layers,the longer are the strips.

The coilmade by the method of the invention is characterized in that the strips between the wire windings are bevelled at least at one end.

The arrangement for carrying out the method (Of the invention may comprise a cutting apparatus that separates the strips provided with a bevelled end off the supply roller. In order to cause the incisions to zigzag a cutting mechanism is provided which between two successive incisions is rocked about a surface which is at right angles to the diredtion in which the strip is moved.

The invention will be more clearly understood by reference drawing in which:

Figure 1 is a perspective view of a wire coil being wound in accordance with the present invention; a

Figure 2 is another View thereof showing the bevelled insulation layer having the sharp edge at the other side of the coil;

Figure 3 illustrates an insulation strip having a single bevelled edge in accordance with the present invention;

Figure 4 illustrates a strip of insulation material of undetermined length which is cut in accordance with the present invention;

Figure 4a illustrates a single piece of insulation material having both its edges 1: *velled; and,

Figures 5 and 6 illustrate details of the mechanisms adapted to cut the insulation strips in accordance with the present invention.

Figure 1 is a perspective view of a wire coil 10 shown at the moment when a paper strip 13 is slipped between a completed layer of windings 11 and 'the winding wire 12. The strip 13 is provided with a bevelled end 14 andis fed so that the sharp point 15 of this end is adjacent that side of the bobbin where it can be gripped by the wire 12 and can be wound around the winding layer 11.

Figure 2 shows the same coil after a new layer of wire windings has been wound over the paper strip 13. Thus, the wire winding is adjacent the right hand flange of the bobbin to the accompanying strips of unequal length are a manner that the larger the diameter of the and this time the strip has a bevelled end such that the sharp point 15 is located adjacent the right hand flange. Therefore it follows that it is important that the strips should be fed so that the sharp points arrive successively on the left and on the right flange.

Figure 3 shows a single strip having only one bevelled end.

Figure 4: shows a strip of undetermined length, the diagonal lines shown indicate the manner in which the strip must be cut in order that the sharp point of the strip is caused to be fed successively adjacent the left hand and the right hand flange of the bobbin. As is clearly shown in Figure 4:

these incisions zig-and-zag. The arrangement adapted for this purpose is shown in Figures 5 and 6. It comprises a cutting mechanism 20, 21 mounted on a shaft 23. The cutter 20 is Vertically slidable on the shaft 23 by means of a key-guide, whereas the cutter 21 is fast thereon. The shaft 23 is journalled in the bearing 24:; the rotary movement is ensured by a crank 25 and a rod 26; the cutter 20 is moved up and down by a rod 27. It is clearly shown in Figure 6 in what manner the arrangement operates. The strip 13 is first severed in position A of the cutting mechanism and then in position B. This arrangement is highly effective as it permits of the strips being fed rapidly and properly on to the coils to be wound.

Claims:

1. A method of winding transformer coils composed of alternate layers of wire windings and coiled insulation strips which comprises bevelling at least one of the ends of each of the insulation strips before they are wound and feeding the strip so that the sharp point of the bevelled end is adjacent that side of the bobbin where the strip is gripped by the :Tlnding Wire.

2. A method as claimed in claim 1, in which the strips are fed and are cut at proper lengths from a supply and in which these strips are severed so that the incisions formed are slanting with respect to the longitudinal axis of the strip so that the successive incisions zigzag.

3. A method as claimed in claim 1, in which wound in such layers, the longer are the strips.

4. A wire coil which comprises alternate layers of Wire windings and coiled strips of a material adapted to effectively separate these windings, said strips being bevelled at least at one end.

5. A wire coil as claimed in claim 4:, in A which the strips thereof are of unequal length such that the larger the diameter of the layers,

the longer the strips.

HENDRIK DE JONG.

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