DE8809122U1 - Coil body for a transformer - Google Patents

Description

. 886 H 12DE

Siemens AG

Coil body for a transformer 5

The innovation relates to a coil former for a low-power transformer for communications technology, the iron core of which has an M or E-I section and which has melted-in connection pins on the end faces on at least one side.

With coil bodies for particularly small eg so-called EK-20 core coils, the problem arises that the air &ugr;&oacgr; creepage distances between the core and the connection pins become too small. For automatic winding and dip soldering of these connection pins However, these must be completely freely accessible, so that leakage current extensions must not be provided.

The aim of the innovation is to provide a suitable solution for this.

This is the case with a coil former for a low-power transformer for communications technology, the iron core of which has an M- or E-I-section and which has melted-in connection pins on the end faces on at least one side according to The innovation is solved by at least the flange ribs that carry the pins being widened outwards from the core hole to form a funnel.

Advantageous further developments of the subject matter of the innovation can be found in the subclaims.

The innovation is explained in more detail below using five figures.

Figure 1 shows the entire coil in exploded view

Gz 1 PhI / 15.7.1988 02 01

88 6 1 &eegr; 2 OE '

Figure 2 shows the coil body with an additional element inserted on one side.

Figure 3 shows the right part of the coil body. 5

Figure 4 shows an additional insulating element.

Figure 5 shows the right part of the coil body 10

turned by 90 degrees.

The figures show a coil body 1, which is provided with connection pins 2, 3, 4 on the flanges, which are led out of the flange axially on the one hand and radially on the other. The core in this case is designed as a type of double-E core, consisting of parts 16 and 17.

Since the connection pins 2, 3, 4 must be freely accessible for winding and dip soldering, a creepage current extension rib can no longer be attached to the core on the coil body. For this reason, a chamfer 7 of 20° and an additional step 8 of 0.7 mm are attached to the flange ribs 5, 6, which carry the pins. This is sufficient to extend the creepage path at a low voltage. For higher requirements, an H-shaped cover part 9, which also has insertion bevels 10, is inserted into the bevels 7, thereby extending the creepage and clearance distances. Curves and bevels 13 are also arranged on the core hole 11 and on the flange parts 12 to make it easier to assemble the cores.

The cover part 9 is H-shaped and symmetrical in profile. In the middle of the cover part 9 there is a recess which ensures that the spring 15 has the same spring travel with or without the cover part 9. The cover part is only installed after winding or touch soldering and after assembling the two core halves. It is held and adjusted by the spring 15. On the outside, one of its legs projects beyond the flange corners.

02 02

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6 ml 2 DE

The coil body 1 and the cover part 9 are injection-molded from flame-retardant material.

Figure 5 shows the right flange part rotated by 90°. This shows that, as already mentioned, curves 18 are also provided on the core hole in this plane and bevels 13 are provided at the end of the flange parts 12.

In this way, a coil body is created which avoids the difficulties mentioned at the beginning during automatic winding under load and cold stretches &igr;

4 Protection claims

5 Figures 15

02

Claims (4)

•88 H 12DE Protection claims 1. Coil body for a low-power transformer for communications engineering, whose iron core has an M- or E-I section and which has connecting pins melted into the end faces on at least one side, characterized in that at least the flange ribs (5, 6) carry the pins (2, 3, 4) and are widened outwards from the core hole to form a funnel shape (7). 2. Coil body according to claim 1, characterized in that a straight step (8) is provided following the respective funnel-shaped extension (7). 3. Coil body according to one of the preceding claims, characterized in that a prefil ^-shaped insulating material piece (9), which has an opening 14 in the middle, is inserted into the funnel-shaped Extension is inserted so that the vertical legs of the &EEgr; shape rest on the side of the M- or &Egr;-I-shaped core that is then plugged in and the outer legs protrude beyond the flange corners to increase the creepage distance. 25 4. Coil body according to claim 3, characterized in that the two core halves are held together by M-shaped springs (15), which can be snapped onto the coil body and engage with the center of the M in the opening of the H-shaped element (9). 03 01