EP0793243B1 - Transformer - Google Patents

Description

Technical field

The present invention relates to a transformer according to the preamble of claim 1.

Transformers are used in a wide variety of areas. Under Others are transformers for the operation of halogen incandescent lamps used, with an input voltage of e.g. 230 volts or 240 ... 245 volts is transformed into an output voltage of 6 volts, 12 volts or 24 volts. Output transformers in electronic converters for halogen lamps transform from half the mains voltage (e.g. 115 volts) to e.g. 12 volts.

State of the art

A winding body and a cover cap, each made of plastic, for one such transformers are e.g. from the company NORWE, Ing. Norbert Weiner GmbH offered (see product brochure "Protection class bobbin UNI ", 11/1991). The known transformer is relatively complex built up. The cover cap is in one piece with walls relatively smaller Wall thickness trained. In addition to the relatively complex structure, there is a Another disadvantage of the known transformer in that the assembly of Transformer winding body on the one hand and the part consisting of cover cap and walls, on the other hand, is difficult because of multiple points of the winding body against the corresponding points of the part from the cap and walls correctly positioned before plugging together need to be bent and walls mechanically slightly against each other can be.

Another disadvantage of the known transformer is that in particular during continuous operation the temperature increase of the windings and the plastic surface adjacent to it is relatively large. The known This means that the transformer can only operate up to a correspondingly reduced ambient temperature be operated in which a permanent insulation ability is guaranteed.

The document DE-A-3 241 408 discloses a transformer with a winding body and an insulating hood. The insulating hood is U-shaped and insulated the windings arranged on the winding body against each other and opposite the core sheets of the transformer. The insulation hood is on bridged its open end by a bracket to prevent the insulation hood is inadvertently or easily separated from the winding body can be.

Presentation of the invention

Starting from this prior art, the object of the invention based on specifying a transformer that has lower temperature values and easy to assemble.

According to the invention, this object is achieved by a transformer which is defined in the claims.

The transformer according to the invention is designed so that on the one hand Much of the heat developed is dissipated and that on the other hand adequate insulation between the primary and secondary windings is guaranteed.

This allows the maximum permissible ambient temperature of the transformer increase or at substantially the same maximum permissible Ambient temperature can be cheaper transformer components Use (windings, core) with greater heat development.

At the same time, the cover cap or, preferably, in one piece with it trained components, namely a first partition and second Partitions designed so that the assembly of winding body and cover cap is made possible in a simple manner.

The simple and error-free assembly of winding bodies with differently designed chambers for the primary winding or Secondary winding on the one hand and cover cap on the other hand also serve first coding element, which is arranged on the winding body, and a second coding element, which corresponds to the first coding element and on the cover cap or on a component connected to it is arranged.

The manufacture of the cover cap and the winding body is due their wall thicknesses in spraying technology relatively simple; to the injection molds there are no special requirements. For the cap tool no sliders are required. Overall thus achieved relatively low tool costs.

The good insulating properties of the transformer according to the invention serve also an insulating bar which is provided on the winding body.

The transformer according to the invention is further configured in such a way that the generation of safety extra-low voltages (Safety Extra Low Voltage SELV) is made possible.

Description of the drawings

Fig. 1-9

einen Wicklungskörper für eine Ausführungsform des erfindungsgemäßen Transformators;

Fig. 10 - 15

eine Abdeckkappe für eine Ausführungsform des erfindungsgemäßen Transformators; und

Fig. 16 - 24

eine Ausführungsform des erfindungsgemäßen Transformators.

The present invention is first described in general terms below, and the invention is subsequently explained in more detail using a preferred exemplary embodiment in conjunction with the figures. Show:

Fig. 1-9

a winding body for an embodiment of the transformer according to the invention;

Figures 10-15

a cover cap for an embodiment of the transformer according to the invention; and

Figures 16-24

an embodiment of the transformer according to the invention.

The invention relates to a transformer, in particular in a frequency range is operated above the mains frequency. The transformer has at least one primary winding and at least one secondary winding on and a winding body 1 (Fig. 1-9, 16-24), on which in a first chamber 11 the primary winding and on that in a second chamber 12 the secondary winding is arranged.

A core 2 (FIGS. 16, 20, 22 and 24) can be inserted into the winding body in the preferred operating range (with frequencies above the mains frequency) is in particular a ferrite core.

The winding body has a receiving element 13 (FIGS. 1-3, 6), in particular a groove which receives a cover cap 3 (Fig. 10-17, 19, 21 and 24).

The covering cap 3 (FIG. 16) covers only a partial area of the primary winding, which is wound in the first chamber 11, and a portion the secondary winding, which is wound in the second chamber 12 is. This is the section in which the primary winding and the secondary winding adjoin each other. The cover cap 3 is thus designed that much of the heat developed in the two windings is dissipated becomes. In the area of the two windings, which is not through the cover cap is covered, the heat is directly to the environment of the transformer. On the other hand, the cover cap ensures due to their dimensions, however, adequate insulation between primary and secondary winding; a ("first") air and Creepage distance between the primary and secondary windings runs along the cap and is at least 4.5 millimeters, in particular 4.8 Millimeter. The first clearance and creepage distance on the one hand runs from the primary winding over the cover 3 to the secondary winding (or in the opposite direction); on the other hand, the first clearance and creepage distance runs from the primary winding via a first chamber wall 111, a first Partition wall 31 and a second chamber wall 112 to the secondary winding. Furthermore, the first clearance and creepage distance on the one hand runs from the primary winding below a plate 32 (Figures 10-16) to the secondary winding and on the other hand from the primary winding horizontally across the Receiving element 13.

With regard to the first-mentioned course of the first air and creepage distance the width of the cap surface is at least 4.5 millimeters; a preferred value is 4.8 millimeters. Already at this value is even with unfavorable arrangement of the windings (windings, the should be arranged side by side are actually on top of each other arranged) sufficient insulation is formed.

The covering cap 3 is essentially perpendicular to the covering cap 3 arranged first partition 31 (Fig. 16 and 24) formed in assembled state between the first chamber 11 and the first chamber wall 111 and second chamber 12 or second chamber wall 112 is arranged. The air and creepage distance over the first partition is thus meandering extended. The wall thickness of the first or second chamber wall is e.g. 0.4 millimeters and the wall thickness of the first partition is 0.6 millimeters.

The cover cap 3 and the first partition 31 are preferably in one piece educated. In particular, cover cap 3 and first partition are 31 further with a plate 32 (Fig. 10-13, 16, 19-24) on which in the assembled State of the core rests, and in one piece with second partitions 33 educated. The plate 32 is arranged parallel to the cover cap 3. The second partitions 33 connect the cap 3 and the plate 32 in the way with each other that plate 32, second partitions 33 and cap 3 form a step-like structure. The stability of complex 3 - 31-33-32 is achieved in particular by the plate 32.

The first chamber 11 faces the second chamber 12 Side up the first chamber wall 111, while the second chamber 12 on hers the second chamber wall 112 facing the first chamber 11 has (Figure 1). So there is one between primary and secondary winding double-walled structure is provided, the first partition 31 is inserted between the two chamber walls.

Both chamber walls 111 and 112 are parallel to each other and in the manner spaced that the first partition 31 at least in the assembled state arranged in a partial area between the two chamber walls 111, 112 is.

The first partition 31 is U-shaped (Figure 12), the U-legs the partition 31 in the assembled state the middle leg of the Enclose core 2 on the side.

The already mentioned second partitions 33, which are preferably in one piece are formed with the cover cap, serve to isolate the first or the second winding in each case opposite the core 2.

A second clearance and creepage distance runs between the primary winding and Core 2 on the one hand and between secondary winding and core 2 on the other; it is preferably at least 2.0 mm and in particular 3 mm.

The second air and creepage distance is through the second partition walls 33 lengthened, in particular about 2.5 mm - 2.8 mm above the top of the Protruding core 2.

The first and the second chamber of the winding body 1 are in particular of different sizes (chamber 1 is larger than chamber 2). In this case a first coding element 14 on the winding body 1 (FIGS. 1, 17; e.g. a nose) arranged, which corresponds to a second coding element 34 (FIG. 11), that on the cap 3 or one connected to the cap Part (e.g. 33) is arranged.

The first and the second chamber of the winding body 1 are in particular not only of different sizes, but also differently isolated: the Insulation thickness between the primary winding and core is 0.4 mm (cf. hatched area in Figure 5, lateral areas and upper area), while the insulating material thickness between the secondary winding and the core 0.8 mm (see hatched area in Figure 8). This configuration brings Advantages for the placement of the transformer (only less insulation of the Components on the board that are connected to the primary winding are required towards the core).

The winding body 1 of the transformer has an insulating web 15 (FIGS. 1, 4, 7) which is arranged horizontally and therefore parallel to the core 2 (FIG. 22)

Spacer feet 35 (FIGS. 10-13, 16, 19-24) are arranged on the plate 32, which are used to fix the transformer on a circuit board.

The invention also relates to the covering cap 3 (FIGS. 10-19, 21-24) or complex 3 - 31 - 33 - 32 as well as the corresponding winding body 1 (Figures 1 - 9)

The relatively easy assembly of the complex 3 - 31 - 33 - 32 and the Corresponding winding body 1 results from the fact that before Push the two parts 3 - 31 - 33 - 32 and 1 together only the first Position the partition walls 31 correctly in relation to the receiving element (groove) 13 are.

The structure of the winding body 1, the cover 3 and the entire Transformer with the ferrite core 2 is shown in detail in the figures.

In Fig. The winding body 1 is shown, the first chamber 11 and has a second chamber 12. A first chamber wall 111 of the first Chamber 11 and a second chamber wall 112 of the second chamber 12 immediately adjacent, parallel and spaced in such a way that a first Partition (31; Fig. 10) in the assembled state between the first and second chamber is arranged. There are two insulating bars on the winding body 1 15 formed, which in the position shown in FIG. 1 Winding body are formed horizontally. The insulating bars are arranged that an air and creepage distance of at least 3 mm between around wire winding mandrels 16 wires and one in the coil or Winding body 1 inserted (ferrite) core is forcibly realized; she are so arranged that even with production-related fluctuations the winding wire position is adequately insulated.

1 further shows a nose 14 formed on the winding body 1 ("first coding element"), which with a second coding element (34; FIG 15), which on the cover cap or on one connected to the cover cap Part is arranged, corresponds. Furthermore, a receiving element 13, which is designed as a groove, shown in the figure, which serves to accommodate the actual cap (3; Fig. 10).

FIG. 2 shows a plan view of the winding body 1 according to FIG. 1, with the Components shown and described there.

Fig. 3 shows a view of the winding body from below, numbers 1-8 of connections are stamped into the winding body.

Fig. 4 shows a side view of the winding body, the first Coding element 14 in the upper and lower region of the winding body 1 and an insulating web 15 are shown.

Fig. 5 shows the inside of the first chamber 11, and Fig. 6 shows the configuration the first and second chamber walls 111, 112, which are the receiving element Form 13 for receiving the actual cap.

Fig. 7 again shows a side view of the winding body with a Insulating bridge 15.

Fig. 8 shows the inside of the second chamber 12 and Fig. 9 also shows that Interior of the second chamber 12 with the second chamber wall 112.

10 shows the cover cap 3, which has a partition 31, with side walls, and formed with a substantially horizontal plate 32 is. This makes the complex cover cap 3, partitions 31, 33 and plate 32 mechanically sufficiently stable. The plate 32 is preferably 1 millimeter thick. It serves as a support surface for the (ferrite) core 2 and as a support for Spacer feet 35.

Fig. 11 shows this body with second partitions 33, the plate 32 and the spacer feet 35.

FIG. 12 shows the section C-C according to FIG. 10 and FIG. 13 the section D-D according to Fig. 10.

In Fig. 14 this body is again shown from below, the is formed in one piece; it includes the actual cap 3, the first Partition 31, the plate 32, second partitions 33, as in the figure can be formed, the second coding element 34 and spacer feet 35.

Fig. 15 shows the view of the body shown in Fig. 14 from above.

16 shows the transformer according to the invention, the one described above Winding body 1, a ferrite core 2 and the cover cap 3 with the connected components (31, 32, 33, 34 and 35), the first partition 31 lies between the chamber walls 111 and 112.

Fig. 17 is a top view of the transformer while Fig. 18 is the Transformer from below.

FIG. 19 shows the transformer from one side, while FIG. 20 shows one Section through the transformer. 21 again shows a side view of the transformer, while Fig. 22 is a section through the Represents transformer. 23 shows the transformer from the side, 24 shows a section through the transformer.

The covering cap 3 or the complex 3 - 31 - 33 - 32 on the one hand and the Winding body 1, on the other hand, each consist of plastic, which in is known to be used for transformers.

Claims (16)

1. Transformer with at least one primary winding and at least one secondary winding, with a unipartite winding assembly (1), on which the primary winding is arranged in a first chamber (11) and on which the secondary winding is arranged in a second chamber (12) into which a core, in particular a ferrite core (2) can be inserted, and with a cover cap (3), the winding assembly (1) having a holding element (13) for a cover cap (3), the cover cap (3), being constructed with a first partition (31), which is arranged essentially perpendicular to the cover cap (3) and is arranged in the assembled state between the first chamber (11) and second chamber (12), characterized in that the cover cap (3) covers only a subregion of the primary winding and the secondary winding, in which subregion the primary winding and the secondary winding adjoin one another, and the cover cap (3) is connected to a plate (32) on which the core (2) is arranged in the assembled state.
2. Transformer according to Claim 1, characterized in that the cover cap (3) and first partition (31) are of unipartite construction.
3. Transformer according to one of the preceding claims, characterized in that the first chamber (11) has a first chamber wall (111) on its side facing the second chamber (12), in that the second chamber (12) has a second chamber wall (112) on its side facing the first chamber (11), and in that the first chamber wall (111) and the second chamber wall (112) are constructed parallel to and spaced apart from one another in the way that the first partition (31) is arranged in the assembled state at least in a subregion between the chamber walls (111, 112).
4. Transformer according to one of the preceding claims, characterized in that the partition (31) is of U-shaped construction, and in that, in the assembled state, the U-limbs of the partition (31) laterally surround a part of the core (2) which is arranged in the winding assembly (1).
5. Transformer according to one of the preceding claims, characterized in that the cover cap (3) is connected to second partitions (33) which in the assembled state are arranged between the first chamber (11) and second chamber (12), on the one hand, and core (2), on the other hand.
6. Transformer according to Claim 5, characterized in that the cover cap (3), first partition (31), plate (32) and/or second partitions (33) are of unipartite construction.
7. Transformer according to one of the preceding claims, characterized in that the winding assembly (1) has a first coder element (14) which corresponds to a second coder element (34) which is arranged on the cover cap (3) or on a part connected to the cover cap.
8. Transformer according to one of the preceding claims, characterized in that a first air clearance and leakage path between the primary winding and the secondary winding is at least 4.5 mm, in particular 4.8 mm, in the assembled state.
9. Transformer according to one of the preceding claims, characterized in that the first air clearance and leakage path runs along the cover cap (3).
10. Transformer according to one of the preceding claims, characterized in that the first air clearance and leakage path runs along the first chamber wall (111), the first partition (31) and the second chamber wall (112).
11. Transformer according to one of the preceding claims, characterized in that a second air clearance and leakage path is at least 2.0 mm, in particular 3 mm, between the primary winding and core (2), on the one hand, and between the secondary winding and core (2), on the other hand.
12. Transformer according to Claim 11, characterized in that the second air clearance and leakage path runs above the second partitions (33), which are connected to the cover cap (3) and below the plate (32).
13. Transformer according to one of the preceding claims, characterized in that the winding assembly (1) has an insulating web (15) parallel to the core (2).
14. Transformer according to one of the preceding claims, characterized in that spacer feet (35) are arranged on the plate (32).
15. Transformer according to one of the preceding claims, characterized in that the wall thickness of the first chamber wall (111), and the wall thickness of the second chamber wall (112) is in each case 0.4 millimetres.
16. Transformer according to one of the preceding claims, characterized in that the wall thickness of the first partition (31) is 0.6 millimetres.

Images