FI116427B - Transformer or choke - Google Patents

Description

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This invention relates to a transformer or a choke having coils 5 arranged side by side in the axial direction of the winding and separated on the one hand and at least partially separated by a core of magnetically conductive material on the insulating layer.

Transformers or inductors of the type described above are known, for example, from European Standard EN 60742, page 60, 10. It is recommended therefor to separate and insulate each of the two disc-shaped coils adjacent to each other and to form single or multi-part coil bodies made of homogeneous injection molding material which are practically rigid. The one-piece coil-15 body has an E-shape when viewed in a section taken parallel to the axis of the winding. The two-part coil body comprises two parts, each of which, as seen in section, has a C-shape. Both the one-piece and the multi-part reel core are open on the side 20 of the winding away from the shaft. In order to provide insulation here, a free air gap is left between the respective wall of the core winding space and the winding. Each of the normally two winding states is provided with a one-piece or multi-part coil body slightly wider than 25 cores to prevent the coil portions v, through the winding states from touching the core.

In addition, a multilayer flexible insulating film adapted to · 'is known from said European standard; between two coils which, when viewed perpendicular to the axis of the coil, overlap. This multilayer insulating film may also have an outwardly open C-shape.

Finally, in this norm, an insulation part is recommended for two coils which, likewise, viewed perpendicular to the direction of winding 35, overlap. This t; * 116427 2 The insulating part consists of a single single-layer flexible film, which is bent to a tubular shape and which serves to receive one or both coils. The end portions of the bent films overlap.

According to the present invention, the initially described transformer or the initially described inductor is proposed that the dielectric layer comprises a single or multilayer flexible dielectric film which follows at least the winding space limiting wall parallel to the core winding axis and facing the winding space limiting wall. The dielectric layer of the present invention is, as is known in the art of injection molding, a one-piece body and therefore guarantees low cost manufacture of a transformer or a choke especially in the case of a bulk product such as transformers or chokes for fluorescent lamps. However, in contrast to the known rigid one-piece coil body, the insulating layer used in accordance with the present invention is flexible so that the space previously left for the air gap can also be filled with an insulating film. Since the insulation provided by the insulating film is considerably better than that provided by the air gap, an insulating film which is substantially thinner than the width of the air gap can be used; 25 is. This allows for denser winding in the winding state. This is further assisted by the flexibility of the dielectric layer whereby. * The insulation layer adapts well to the outline of the winding space.

· .'1 It should also be noted in this connection that> the known rigid one-piece coil body is open on its side away from the axis 30 of the winding, because otherwise it would not be able to wind it. Conversely, when using an insulating film formed in accordance with the present invention, the winding can be positioned when the ends of the insulating film have been bent apart, which is also possible with known tubular bent insulating film. The end portions of the insulating 116427 3 film can then be bent against the coil and overlapped before the core portions are pushed onto the coil.

In order to prevent one coil being manufactured, the coil conductor does not get into the part of the winding space intended for the other coil, the fold must be long enough that its end region contacts the bent and overlapping end portions of the insulating film so that it may even be sponge-shaped bent.

It is preferable to use insulating films made of a plurality of insulating layers, for example by pressing or gluing them together. The insulating layers, in turn, may consist of different insulating materials having different properties. A suitable combination of materials provides "surface insulation systems" which have excellent thermal, electrical and mechanical properties and which, while having a lower thickness of the dielectric, are superior to solid dielectric injection molded insulating systems.

Embodiments of the present invention are described below in connection with the drawings.

Fig. 1 shows a transformer having two windings and · 25 in each winding state, with an isolation system in which each isolation system is configured similarly; Fig. 2 shows a transformer as in Fig. 1, where, however, each insulation system represents a different variant from Fig. 1.

The core of the transformer shown in Fig. 1 comprises two opposed C-shaped arms 1a, Ib and an interlocking core block 2 which only partially fills the interior of the C-shaped arms 1a, Ib. The heart block 2 leaves a corresponding free winding space 35 on both sides.

116427 4

Through each winding space extends a first winding 3 (e.g. a primary winding) and a second winding 4 (e.g. a secondary winding) which is wound around the winding axis 20. Each winding 3,4 is adjacent to the mouth 5 of the winding shaft 20. To separate each winding 3,4, there is an insulating system 5 in the left winding space and an insulating system 15 in the right winding space, each of which is made identical.

The insulating system 5 comprises one insulating film of three layers 10 which follows the core block 2 by parts 6a and 6b, whereby a fold formed by parts 7a, 7b is inserted between each part 6a, 6b. The end portions 9a, 9b of the insulating film 5 are wrapped around the windings 3, 4 and overlap each other. These two end portions 9a, 9b follow the inner wall of the C-shaped core portion la. The end region 8 of the fold formed by each of the insulating film parts 7a, 7b protrudes against the end part 9a of the insulating film 5. In this way, it is prevented that the conductors of either coil 3, 4 cannot enter the corresponding second part of the winding space.

20 The insulation system 15 is - as mentioned - constructed in the same way as the insulation system 5. The corresponding reference numerals only differ by 10, but otherwise the reference numerals are identical.

The transformer shown in Figure 2 differs from the insulation system shown in Figure 1 with respect to the left-hand insulation system 5 only in that the end region of the fold is turned sideways.

The right insulating system 15 in Figure 2: differs from the insulating system shown in Figure 1 in that the end region of the fold is cushioned in cross-section; ; sponge shape, which is specially guaranteed *, so that the wires cannot go from one part of the winding to another.

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Claims (8)

116427 5 Transformer or reactor having two 5 coils (3,4) arranged side by side in the direction of the axis of the coil (20), separated on the one hand and at least partially separated by a core (1a, Ib, 2) of a magnetically conductive material, on the other , characterized in that the dielectric layer consists of a single or multilayer 10 flexible insulating film (5; 15) which follows at least the winding space limiting wall parallel to the axis (20) of the core (1a, Ib, 2) and having the winding space limiting a fold (7a, 7b; 17a, 17b) facing the wall separating the two windings (3,4) from each other when viewed from the direction of the winding axis (20). Transformer or choke I according to claim 1, characterized in that the end region (8; 18) of the fold (7a, 7b; 17a, 17b) of the insulating film (5; 15) protrudes against the winding space limiting core (1a, Ib) opposite it. , 2) against the wall. Transformer or choke according to claim 1, characterized in that the end portions of the insulating film (5;...... 15) follow the opposed, winding space (1a, Ib, 2) wall of the winding. . The transformer or «« * of claim 3. '. a choke, characterized in that the end portions (9a, 9b; 19a, 19b) of the insulating film (5; 15) are incremental with respect to each other. Transformer according to claim 3 or 4, or choke, characterized in that the end region of the fold (7a, 7b; 17a, 17b) of the insulating film (5; 15) protrudes from one another: *. against the two end portions (9a; 19a) of the insulating film (5; 15). • · · 1164? '/! 6: S Transformer j or choke according to Claim 2 or 5, characterized in that the end region (8, 18) of the fold (7a, j 7b; 17a, 17b) is cross-sectional in shape or folding to the side. Transformer or reactor according to one of the preceding claims, characterized in that in the insulating film (5; 15) comprising several layers, these layers consist of different insulating materials having different properties. Transformer or inductor according to one of the preceding claims, characterized in that in one insulating film (5; 15) comprising several layers, these layers are pressed and / or glued to each other. • # ••••••••••••••• 116 11642 /