Background of the Invention
The invention relates to an electrical coil comprising a coil body having end flanges with coil guidance slots. Shell core halves are slipped onto the coil body and have wire guidance slots. A terminal carrier for printed circuit boards has solder terminals 1 and receives the coil. Ends of the winding of the coil are soldered to the solder terminals.
An electrical coil of this type is described, for example, on page 163 of the data book "Ferrite-Weichmagnetisches SIFERRIT-Material", 1982/83 Edition, published by Siemens AG and incorporated herein, and is shown in a dismantled or cut view in FIGS. 1 and 2. Parts such as, for example, the balancing screw and the retaining strap which are not required for an understanding of the invention below are not shown.
This electrical coil comprises a coil body 7 wound with a winding 12 and having wire guidance slots 8. Shell core halves 1, 4, have wire guidance slots 2, 5, and are slipped onto the coil body 7. The shell core halves 1, 4 comprise center blebs 6, 11 or collar-shaped projections having cores 13 or 3 into which a balancing screw (not shown) dips. This balancing screw is screwed to a threaded sleeve (likewise not shown) that is guided in the projection bore 13.
The overall arrangement is placed onto a terminal carrier 9 which carries solder terminals 10 for the winding ends (not shown) of the winding 12.
As a result of its design, the assembly and the winding of this coil body of the electrical coil is largely possible only in a manual fashion.
Summary of the Invention
An object of the present invention is to design this electrical coil such that the winding and the assembly thereof are possible on the basis of largely automated methods.
In order to achieve this object in an electrical coil, the invention provides that one of the end flanges of the coil body is designed as an end plate which carries terminal elements, ends of which form solder terminals and has passages for the sidewalls and for the middle projection or bleb of the one shell core half. The terminal carrier is replaced by an adapter plate that can be put in place on this end plate. This adapter plate has solder terminals on its printed circuit board side which are arranged in a prescribed grid dimension, and which have their ends facing away therefrom soldered to the solder terminals of the end plate.
With the invention, for automatic winding of the coil body, the coil body flange, not having any terminal elements, is replaced by an end plate having terminal elements forming solder terminals. The winding ends of the winding are wrapped directly on these solder terminals by the automatic winding unit. Errors in the terminal occupation, such as occur over and over again given manual winding, are no longer possible here.
As a result of its special design wherein the solder terminals of the terminals elements are displaced into the corner regions of the plate, the end plate equipped with passages for the sidewalls of the shell core and for the center bleb or projection of the shell core keeps the mounting surface for the shell cores free. As a result of the adapter plate fashioned with terminal elements, these electrical coils can be adapted to any arbitrary grid arrangement of a printed circuit board. The adapter plate also permits a use in coils which have already had their dimensions defined. This is enabled without modifying the winding rule and the grid arrangements on printed circuit boards.
The end plate and the adapter plate terminal elements can comprise terminal pins, ends of which elements solder terminals. Those ends of the terminal pins of the adapter plate which face away from the printed circuit board side are guided out of the adapter plate to the terminal pins of the end plate.
Brief Description of the Drawings
FIG. 1 is a perspective view of a coil body with enclosing half shells and a terminal carrier according to the prior art;
FIG. 2 is a cross-sectional view of the assembled coil body with half shells according to the prior art assembly of FIG. 1;
FIG. 3 is a side view of an electrical coil of the invention;
FIG. 4 is a bottom view of an end plate of the invention; and
FIG. 5 shows a bottom view of the end plate of FIG. 4 with the adapter plate of the invention in place.
Description of the Preferred Embodiments
The electrical coil of FIG. 3 has ferrite shell core halves 1, 4 having wire guidance slots 2, 5, said halves being slipped onto a coil body. The coil body comprises an annularly shaped end flange having a centering element 14 which dips into the wire guidance slot 2 of the shell core half 1. At the end face at the opposite side, the coil body wound with a winding 12 carries an end plate 20 (shown in FIG. 4) as an end flange. In its corner regions, this rectangular end plate has terminal elements in the form of solder terminal pins 23 on which the winding ends 24, 25 of the winding 12 are wrapped. These winding ends are guided out through the wire guidance slots 5 of the shell core half 4 and through the wire guidance slots 21 of the end plate 20. The end plate 20 is equipped with passages 27 or 28 for the passage of the shell core walls of the shell core half 4 and of its center or projection.
Reference numeral 30 in FIGS. 3 and 5 indicates an adapter plate which, for the purpose of being mounted on a printed circuit board (not shown here), comprises spacers 31 and solder terminal pins 32 arranged in the grid dimension. In its assembled condition, regions of the adapter plate 30 lie on seats 22, 26 of the end plate 20. The adapter plate 30 has extension or let-down portions 34, 35 acting as catch elements (indicated with dot-dash lines) engaging into peg-like catch elements 29 or into the seats 22, which are additionally fashioned as catch elements.
Those ends 33 of the solder terminal pins 32 of the adapter plate 30 which face away from the printed circuit board side are guided to the terminal pins 23 of the end plate 20 and are soldered thereto, for example by means of flow soldering.
Although various minor changes and modifications might be proposed by those skilled in the art, it will be understood that I wish to include within the claims of the patent warranted hereon all such changes and modifications as reasonably come within my contribution to the art.