DE3920232A1 - Pluggable wiring foil with conductive tracks - has several, loosely stacked foil circuits, with specified raster of soldering eyelets - Google Patents

Abstract

At least at one foil end is a coupling region with soldering eyelets, with the latter coupled to terminal pins of a contact elements. Several flexible wiring foils (2) are loosely superimposed and their soldering eyelets are arranged in a raster cooresponding to a PGA socket (12). Each terminal pin in identical raster penetrates all layers of the wiring foils and contacts one or several soldering eyelets in different planes according to engagement of the raster points. The wiring foils are pref. formed in the connecting region into a rigid coupling plate with firmly secured layers. Each coupling plate may be firmly connected on one side to a holding plate (9). USE/ADVANTAGE - For communication appts. and installations, with flexible shape for variable plug connectors.

Description

The invention relates to a pluggable foil wiring, whose conductor tracks at at least one end Pins of contact elements are connected, especially for electrical equipment Communications engineering.

A pluggable foil wiring according to the generic term of claim 1 is already from the German Patent 34 05 804 known. At this Foil wiring is around the end of the traces having film circuit one from another Foil section bent loop, the ends of which are riveted with the interposition of the foil circuit. In this way, a kink protection is formed Damage to the foil circuit on the sharp Long edge of a connector block prevented.

From an article published in the magazine Elektronik 1966, volume 9, page 268 with the title "Flexible Printing Circuits and Their Possibilities" by Karl Schneider, a flexible film circuit is also known, in which the transition to a socket for receiving cable plugs is for itself are connected with ribbon cables, a hard paper plate is stuck on for reinforcement and is additionally riveted. Further, a cable referred to as flat film circuit is shown (Figures 2 a and 2 b), the z. B. is used to connect inserts with a master device and in which the conductor tracks of one end are connected to a connector strip. The article also mentions that flexible pressure circuits are also designed as multilayer circuits, in which the connection between the individual levels is realized in the form of through-plating.

Finally, in the magazine "engineer digest", Issue 3, March 1980, 19th year under the heading "Electrical flat cables and connection elements" Contribution by H. Holzmann and K.J. Published in gray, in which a larger number of flat cable and Plug variants are shown and described.

The invention has for its object a multi-core, variable in the connection options executable, flexible foil wiring with To create plug-in connections of low height and a Specify manufacturing process for it. This task is according to the invention by the in the characterizing part of claim 1 design features and solved the method features specified in claim 9. Advantageous embodiments of the subject of Claim 1 can be found in the subclaims.  

This foil wiring has one Cable connector the preference that multi-core Line connections of high packing density realized that are flexible, a wide variety Offer connectivity and in commercially available PGA sockets can be inserted. Other advantages are in called the description.

The invention is based on in drawings illustrated embodiments as follows described. The drawings show:

Fig. 1 is a full-foil wiring with plug contact elements at the ends, in the side view;

FIG. 2 shows the foil wiring of FIG. 1, in a top view;

Fig. 3 is a soldered to the pins of a PGA socket end of the foil wiring, in a side view;

Fig. 4 is a foil wiring end with contact elements which are inserted into female contacts of a circuit board mounted on a PGA socket, in the side view.

In Figs. 1 to 4, the flexible film wiring is generally designated 1. It consists of several, for example, two-layer flexible film circuits 2 , which are preferably of the same width and have either the same or different lengths depending on the intended use.

In the exemplary embodiment shown in FIGS . 1 and 2, the foil wiring 1 serves as a line adapter, the individual foil circuits 2 of which have identical external dimensions and which has at least one, but usually at both ends of the foil circuit 2 contact elements 3 , which are in the versions of commercially available PGA bases (Pin grid array socket). Accordingly, the ends of the conductor tracks 4 , 5 open into solder eyes 6 , which are arranged in a grid corresponding to the connections of a PGA base, which usually has a square configuration.

Each film circuit 2 has between the connection areas on an outside 7 z. B. a line grid or network-like conductor pattern, which serves shielding purposes and is used as an earth line. On the other side, referred to as the inner side 8 , the conductor tracks 4 , 5 run parallel to one another, alternately a conductor track 4 serving as an earthing line and a conductor track 5 serving as a signal line. The conductor tracks 4 used as grounding lines end here in pads 6 , which are arranged in a row transversely to the film circuit 2 , seen from the center between the film ends in the first row in each case.

For the production of the foil wiring 1 , the layout for the conductor tracks 4 , 5 and here in particular the arrangement of the solder pads 6 of the signal lines for each of the various foil circuits 2 in the connection area is first individually defined and the circuits are then produced using known manufacturing methods. The film circuits 2 are then placed loosely one above the other in a predetermined sequence, an adhesive film or a thin layer of adhesive being inserted or applied between the connection areas, each covering an area corresponding to the outline of the connection area of the film wiring 1 . This film is a pre-crosslinked, i.e. uncured adhesive film with glass filament fabric (prepreg). Through the adhesive film or adhesive layer, the connection areas of the film circuits 2 are cohesively connected to one another after the application of pressure and heat. In order to ensure good shielding of the signal lines, the film circuits 2 are layered before pressing in such a way that in the first case the line grid or line network is always on the outside, ie below. On the inside 8 there then follows the outside 7 of the next film circuit 2 and so on. The end of the film layers then forms a film at the top, which either only has grounding lines or whose lines on the outside do not require any shielding.

In addition, before the film circuits 2 are pressed on the sides of the connection areas at which the contact elements 3 will later protrude, a holding plate 9 is placed in each case, which mechanically reinforces the wiring ends and in particular with only one or a few layers of film circuits 2 as a fastening base for the contact elements 3 serve. The holding plate 9 can, for. B. be a ceramic plate or an epoxy fiberglass plate, which is also underlaid with adhesive film or an adhesive layer.

After the foil wiring has been prefabricated so far, its connection areas are pressed together to form a mechanically rigid connection plate. Then the connection plates are continuously perforated at the grid points 6 with soldering eyes and the perforated walls are then metallized and plated through. Subsequently, the contact elements 3 are inserted with the ends designed as connecting pins 10 first into the holes in the connecting plates in such a way that they first penetrate the holding plate 9 and then all layers of the film circuits 2 and protrude on the side facing away from the holding plate. The pins 10 can, for. B. in so-called press-fit technology, so self-locking and / or by soldering in the plated-through holes. In this way, the ends of the conductor tracks 4 , 5 are connected in different planes partly to the same and partly to different contact elements 3 . The holding plates 9 and the contact elements 3 of the foil wiring 1 , for example in the form of pin contacts, can be attached both on one and the same outwardly facing side or offset by 180 ° to one another ( FIG. 1).

In the embodiment of the foil wiring 1 shown in FIG. 3, the contact elements 3 are part of a commercially available PGA base 11 (pin / pin version), the connecting pins of which are long enough to be able to connect a packing layer of, for example, up to ten foil circuits 2 to it . If the connection areas of the film wiring pressed together to form connection plates are mechanically sufficiently stable by themselves to securely fasten the connection pins 10 therein, the retaining plates 9 which are otherwise provided can be omitted.

In Fig. 4, a plug connection of the embodiment described above is inserted with contact elements 3 selectively inserted into the connection areas of the foil wiring 1 in a PGA socket 12 designed as a socket, the connection pins 13 of which are soldered, for example, into a rigid printed circuit board 14 . Of course, the foil wiring 1 can also be connected to connection pins 13 of PGA sockets 12 , the contact elements of which are designed as socket contacts. Other connection combinations are possible, such as. B. that at one end of the film wiring 1, a PGA socket 11 of one embodiment and at the other end of the film wiring, a PGA socket 12 of another embodiment is provided, which for example can also have a different grid size.

Length and number of film circuits 2 are determined as required. Their width dimensions preferably correspond to the edge length of a PGA base 11 , 12 . Because the individual film circuits 2 can be extremely thin and therefore very flexible perpendicular to the conductor track levels and also have no fixed connection between the connection ends, the film wiring 1 remains very flexible even with a relatively high number of film layers. This allows a good use of space in confined spaces and a relatively high current load on the wiring due to optimal heat dissipation. A shrink tube, which prevents bulging or fanning out of the film circuits 2 , is expediently arranged in the central region only in the case of excessively long film wirings 1 . The shrink tube is omitted if one or more further plug connections are provided between plug connections of the foil wiring ends, which serve as T branches.

Claims (10)

1. Pluggable foil wiring with conductor tracks, which have at least one end with a connection area having solder eyes, in which the solder eyes are connected to pins of contact elements , in particular for electrical communications equipment, characterized in that several flexible film circuits ( 2 ) are essentially loose lie one above the other, the soldering eyes ( 6 ) of which are arranged in a grid corresponding to the connections of a PGA base (for example 12), such that each of the connection pins ( 10 ) fastened in the same grid passes through all layers of the film circuits ( 2 ) and therein each after the grid points have been occupied, one or more pads ( 6 ) in different planes are contacted. 2. Foil wiring according to claim 1, characterized in that the foil circuits ( 2 ) are formed in each connection area to form a rigid, integrally attached connection plate. 3. Foil wiring according to claim 2, characterized in that each connection plate is integrally connected on one side with a holding plate ( 9 ). 4. Foil wiring according to claim 1 to 3, characterized in that the connection areas of the foil circuits ( 2 ) at the occupied grid points have through-metallized holes, in each of which a connector pin ( 10 ) is soldered. 5. Foil wiring according to claim 1, characterized in that the connecting pins ( 10 ) are part of the contact elements ( 3 ) of a PGA base ( 11 , 12 ). 6. Foil wiring according to claim 1, characterized in that the foil circuits ( 2 ) have two layers and between the connection areas on one side (outside 7 ) a grid or network-like conductor pattern and on the other side (inside 8 ) parallel conductor tracks ( 4 , 5 ) have. 7. Foil wiring according to claim 6, characterized in that the superimposed foil circuits ( 2 ) have a sequence in which an inner side ( 8 ) with parallel conductor tracks ( 4 , 5 ) follows an outer side ( 7 ) with a grid or mesh-like conductor track pattern. 8. Foil wiring according to claim 6, characterized in that the solder eyes ( 6 ) of the conductor tracks provided as grounding lines (z. B. 5) are arranged in a row. 9.Method for producing a pluggable foil wiring with conductor tracks which at least one end has a connection area with soldering eyes, in which the soldering eyes are connected with connection pins of contact elements, in particular for electrical communications equipment, characterized by the use of the following process steps:

• a) making a plurality of film circuits ( 2 ) with individually defined pads ( 6 ) in the connection area, which are arranged in a grid corresponding to the connections of a PGA base ( 11 );
• b) superimposing the intended number of film circuits ( 2 ) in such a way that the inside ( 8 ) of a first, the outside ( 7 ) of the next film circuit follows, an adhesive layer or an adhesive film being applied in the connection areas between two film circuits ( 2 ) is inserted;
• c) pressing the arrangement in the connection areas by the action of pressure and heat into mechanically rigid connection plates;
• d) Punching the connection plates at the grid points covered with soldering eyes ( 6 ), metallizing the hole walls and inserting the connection pins ( 10 ) into the plated-through holes.

10. The method according to claim 9, characterized in that before the pressing to terminal plates on the sides of the connection areas, at which the contact elements ( 3 ) are later to protrude, an adhesive layer or an adhesive film is applied and a holding plate ( 9 ) are placed thereon.