EP0070783B1 - Coil spacer - Google Patents

Abstract

1. A winding packing member for winding a winding wire on a magnetic core of the kind comprising an elongate body portion which is adapted to be placed in cornerwise relationship on an edge of said core characterised in that it comprises at least two radially projecting retaining elements (20) in combination with recesses (11) in the body portion, which are adapted to fit on to the retaining elements (20, 20') of a subjacent packing member (31a, 33a).

Description

The present invention relates to a winding block for winding a winding wire on a magnetic core.

Such shims are generally of the type comprising an elongated body adapted to be placed in a corner on each angle of a core to allow direct winding of a wire on the latter. These known wedges have the disadvantage of being heavy and expensive.

Also, a first object of the present invention is to provide a shim, free from these drawbacks.

A second object of the present invention is to provide a shim allowing the separation of various winding layers or of various windings on the same core.

In fact, according to the usual techniques, the various windings of a transformer or an inductor are generally wound on each other on a coil body.

The use of these winding techniques limits the admissible current density in the windings because of the poor quality of heat dissipation specific to this type of winding.

In order to improve dissipation, it has been proposed to separate the winding layers or the windings and to leave a ventilation channel between them.

There are already devices allowing such separation. In general, they comprise a winding cage composed of a frame which can be fitted onto a magnetic core of suitable dimensions and around which a first winding can be wound.

The cage has, at various points on its edges, slides projecting outwards, into which corner rods can be slid. These rods, arranged between each layer, thus allow a ventilation channel to be left between them.

This technique is not applicable for direct winding on a magnetic core, because in this case, we are just trying to do without a body or a winding cage. In addition, the use of this technique involves the production of a cage for each type of core, which consequently makes it relatively expensive.

In this perspective, the invention proposes a wedge of the kind considered, characterized by the combination of at least two retaining elements projecting radially with recesses adapted to fit onto the retaining elements of an underlying wedge.

While lightening the body of the shim, this arrangement allows direct winding on a magnetic core, several ventilation channels which can be provided between the various layers of the winding, without the body of the coils or the winding cages.

• - la fig. 1 est une vue de côté et en coupe suivant la ligne I-I de la fig. 2 d'une cale selon la présente invention;
• - la fig. 2 est une vue en élévation et en coupe partielle de la cale suivant la ligne II-II de la fig. 1;
• - les fig. 3 et 4 sont des vues en coupe partielle, transversale et longitudinale illustrant l'utilisation de cales selon la présente invention.

The characteristics and advantages of the present invention will become apparent from the description which follows, with reference to the accompanying drawings in which:

• - fig. 1 is a side view in section along line II of FIG. 2 of a wedge according to the present invention;
• - fig. 2 is an elevational view in partial section of the wedge along line II-II of FIG. 1;
• - figs. 3 and 4 are views in partial, transverse and longitudinal section illustrating the use of wedges according to the present invention.

Depending on the embodiment chosen and shown in FIGS. 1 to 4, a shim 10 is formed of an elongated body having recesses 11 delimited by blanks 17, 17 'and closed at the ends by two end walls 12,12'.

A median veil 14 is disposed between the walls 12, 12 ′ inside the body, so that said body is divided, lengthwise, into two symmetrical parts, the recesses 11 extending from side to side. other of said median veil. The veil 14 is indented at 15 in its thickness, and the indentation 15 is in the form of an isosceles right triangle.

The recesses 11 are delimited by a plurality of transverse partitions 16, 16 'arranged inside the body between the web 14 and each of the blanks 17, 17', at regular intervals.

The lower edges 24, 24 'of the partitions 16, 16' cooperate with the notch 15 so that the edges 24, 24 'and the notch 15 form an isosceles right triangle whose base is between the edges 25, 25' blanks 17, 17 '. The body is thus adapted to be placed in a corner on an edge, while being partially hollowed out.

According to the embodiment shown, each end of the body is provided with a retaining element 20, 20 ′, projecting radially, in the form of cheeks, these cheeks being indented in their middle at 21, 21 ′. The notches 21, 21 'are rectangular. The retains 20, 20 'are offset from the ends of the body, so that the external faces 22, 22' of the retains 20, 20 'are substantially perpendicular to the internal faces 13,13' of the walls 12,12 '.

In fig. 3 and 4, it appears that the shim is remarkable for the combination of the retaining protruding elements 20, 20 ', with the recesses 11, adjacent to the walls 12, 12', which are adapted to fit onto the retaining elements 20 , 20 ′ of an underlying wedge, the retaining protruding elements 20, 20 ′ having the shape of a cheek with a profile complementary to that of the recesses 11, with a notch 21,21 ′ of engagement on the median veil 14 of the underlying shim (see for example the fitting of the shim 33a on the shim 31 a).

According to a first mode of use of the shim described and shown, a shim is arranged in a corner on each edge of a magnetic core. We then directly coil the bobi wire swims around the nucleus with wedges.

The cheek-retained retainers 20,20 'prevent the winding wire from slipping, this avoiding having to attach the last turns of each layer, which saves winding time compared to techniques of prior art.

A second mode of use is illustrated in FIGS. 3 and 4. Four wedges 31a, 31b, 31c, 31 are arranged in a corner on the edges 30a, 30b, 30c, 30d of a magnetic core 29. We then proceed to wind a first layer 32. We then embed the shims 33a, 33b, 33c, 33d respectively on the shims 31 a, 31 b, 31 c, 31 d. We then proceed to wind a second layer 34. According to the example chosen and shown, we will also do the same for the winding of a layer 36 thanks to the embedding of the shims 35a, 35b, 35c, 35d on the shims 33a, 33b, 33c, 33d.

The shims 31 a to 31 d, 33a to 33d, 35a to 35d are immobilized radially by the winding tension of the layers 32, 34, 36.

In fig. 3, it can be seen that the median web 14 of the various wedges 22 and 35 cooperates with the notches 21 of the retains 20 respectively of the wedges 31 and 33, ensuring their relative immobilization in rotation.

In fig. 4, it can also be seen that the retains 20 and 20 ′ of the shims 31 and 33 cooperate with the walls 12, 12 ′ of the shims 33 and 35, so that the shims are immobilized with respect to each other in the longitudinal direction.

Thus, according to the invention, the various winding layers obtained are separated by ventilation channels 40, 41 and 42, thus making it possible to raise the current density in the winding wire compared to that possible in a conventional winding. where the various layers are glued to each other.

In addition, according to the invention, the shims cooperate with each other in such a way that they cannot slide over each other, thus fixing, once and for all, the winding layers in the desired position, without risk. to see, subsequently, these layers accidentally slide relative to each other, thus destroying the winding.

Of course, the invention is not limited to the embodiments described and shown, but encompasses all variants, without departing from the scope of the present invention.

In particular, the wedge, described in support of FIGS. 1 to 4, has been shown with a notch 15 in the shape of a right isosceles triangle thus allowing the adaptation of the wedge wedge on a core with rectangular section.

It is obvious that the shape of the notch 15 can be modified to allow the adaptation of the shim on the edges of cores whose planes form an angle other than 90 °.

In addition, according to the embodiment shown, the blanks 17, 17 'of the body cooperate with a median web 14 and partitions 16, 16', thus making it possible to produce a partially hollowed-out body.

The invention cannot be limited to the arrangement shown, a partially hollowed-out body which can be obtained by other means known to those skilled in the art.

Likewise, the shape of the retainers 20, 20 ′, indented at 21, 21 ′, has of course been determined as a function of the arrangement of the median web 14 and the blanks 17, 17 ′. If this arrangement was modified, the shape of the retentions 20, 20 'would consequently be so as to allow the cooperation described in support of FIGS. 3 and 4.

Claims (5)

1. A winding packing member for winding a winding wire on a magnetic core of the kind comprising an elongate body portion which is adapted to be placed in cornerwise relationship on an edge of said core characterised in that it comprises at least two radially projecting retaining elements (20) in combination with recesses (11) in the body portion, which are adapted to fit on to the retaining elements (20, 20') of a subjacent packing member (31 a, 33a).

2. A winding packing member according to claim 1 characterised in that said recesses (11) are elongate and transversely partitioned.

3. A winding packing member according to one of claims 1 and 2 characterised in that the recesses (11) extend on respective sides of a central web portion (14).

4. A winding packing member according to claim 3 characterised in that said projecting retaining elements (20, 20') are in the form a side plate member which is complementary in profile to the recesses (11) with a notch (21) for fitting on to the central web portion (14) of a following packing member (33a, 35a).

5. A winding packing member according to any one of claims 1 to 4 characterised in that, the recesses (11) being confined by two terminal walls (12, 12'), the projecting retaining elements (20, 20') are so disposed that the outside surface (22,22') thereof is disposed substantially in alignment with the inside surface (13, 13') of the corresponding terminal wall (12,12').

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