DE2519437A1 - METHOD AND DEVICE FOR CONNECTING FLAT CABLES - Google Patents

Description

Elco Corporation
Willow Grove, Pennsylvania / USA

Method and device for connecting flat conductor cables

The invention inscribed ie ht to a method and a device for the connection of flat conductor cables and in particular to improvements in multi-contact connection devices for the connection of flexible flat conductor cables and the like, as same in the German patent specification (German patent application our reference numeral 15 155

Filing date).

As stated in this patent, have flexible Flat conductor cables usually have a number of flat ribbon-shaped conductors which are in an insulating material, for example Polyesters are embedded, the conductors being arranged generally parallel to one another in a single plane.

Flexible flat conductor cables are becoming increasingly popular in wiring applications used because they are very compact and have advantageous electrical properties. For example it has been found that this type of cable is easily replaced and / or installed even in relatively crowded installation conditions can become costly, difficult even if the relatively crowded installation conditions other common wiring arrangements and could quickly lead to wiring errors.

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The economic usefulness of flexible flat conductor cables, however, was due to the lack of a particularly suitable connection contact impaired.

Connection devices for flat conductor cables are already known, which use both clamp connections and solder connections. Most of these connection devices required part of the cable for receiving the connection device prepare. For example, in many cases it is necessary to remove the insulation from the end of the cable prior to application of the contact on the cable. In other cases, the cable can be drilled beforehand for inclusion part of the contact may be required (see, for example, U.S. Patents 3,675,180 or 3,768,062).

With further connection devices it is not necessary to remove part of the insulating material. The isolation can be pierced by a contact that spreads a conductor of the cable. The contact can then be clamped onto the conductor to make an electrical connection (see U.S. Patent 3,395,380). Disadvantages of this known Arrangement are in the above-mentioned German patent

(German patent application, our file number I5

from the same filing date).

It also became a connector for flexible printed circuit boards proposed having mandrels which penetrate the full thickness of the flexible printed circuit in order to make the connection in this way to be taped onto the flexible printed circuit at a previously drilled location (see US Pat. No. 3,768,062).

This device forms a connector for flexible printed circuits resting on an edge portion of the connector, which extends generally perpendicular to a generally planar base portion. With this arrangement, domes penetrate the are formed on an extension of the frame or edge,

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the full thickness of the flexible circuit on a previously perforated Zone of increased width on the flexible printed circuit. After penetrating the printed circuit the mandrels are bent against an outer layer of the printed circuit. In this known device was continued suggested that, if so desired, these mandrels after fastening the connector against an anvil with appropriate Form pressed to achieve re-entry of the mandrels in the flexible printed circuit. It is I understood that these and other clampable connection devices for flat conductor cables require some preparation of the cable or circuit to be connected to the To accommodate connecting device or that the cable must have a relatively large space between the conductors, to prevent adjacent conductors from making electrical contact with one another. These factors can affect the usability of the cable or the circuit used, and in addition, this can have a significant impact result in economic disadvantages for the use of the cable or the circuit. Furthermore, these known connecting devices result in an electrical contact that has certain undesirable properties. For example the electrical contact between known connecting devices and the conductor cable can be insufficient in number from points so that it does not have satisfactory properties. Furthermore, these give known connecting devices does not have a sufficiently firm mechanical engagement in the conductor, so that there is no satisfactory electrical Contact results over a relatively long service life.

In the above-mentioned German patent is a novel method and a device for connecting flexible flat conductor cables described, in which or in which at least the above-described problems of known devices eliminated are.

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The present invention relates to an improvement of the method described in this German patent specification and the device in order to achieve particularly favorable mechanical and electrical connections.

In particular, no preparation of the cable should be necessary.

Accordingly, the present invention is based on the object to provide an improved method and a device for connecting flat conductor cables, in which a relatively short conductor spacing is possible, with the immediate connection of a connection device at any point along a Length of a flexible flat conductor cable should be made possible and with particularly favorable mechanical and electrical Connections result.

This object is achieved by the invention specified in the patent claims.

By the method according to the invention and the device for Connection of the flexible flat conductor cable, the conductors are complete penetrated to a first electrical and mechanical contact between the conductor part and the at this point To achieve connection device. Furthermore, a clamping device is created to keep the ladder part on a Pinch point that is away from the piercing point of the conductor. This clamping device can be bent over Include part of the cable penetrating device and an abutment body forming a reaction surface; against which the conductor is pressed by the bent part. The bent part of the piercing part and the abutment body cooperate to penetrate at least part of an insulating cover of the conductor part to the conductor to pinch this point remote from the puncture site. This creates a second elec-

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tric and mechanical contact between the conductor and the Connection device and a mechanical contact between the conductor and the connection device created. Furthermore can the clamping point formed by the bent part of the piercing device and the abutment body is part of the Enclose the conductor between the piercing point and the clamping point. The abutment body can be carried by two spring arms are formed in one piece with the connecting device are. These resilient arms can result in a relatively constant force, which in the sense of a firm contact pressure of the bent part of the piercing device against the conductor of the cable.

The piercing member can include two sharpened prongs. These prongs can be sharpened in such a way that they form a prestressed conductor bridge between them when the contact is attached to the flat conductor cable. At the point of this ladder bridge there are die-pressed oppositely directed Projections of the prongs are provided to engage the conductor cable segment of the bridge.

The method according to the invention includes the piercing steps a conductor of a flexible flat conductor cable with a contact at a first point. The contact is then between the through-hole part and an abutment surface on one second point clamped in order to ensure a secure electrical and mechanical contact between the conductor and the connection device to create in the second place. This clamping action can separate or constrain parts of the conductor in order to provide an improved to create electrical contact. Preferably, a die is used to pierce the cable and the To perform bending of the prongs. The die includes a bending surface that cooperates with the prongs. the Bending surface can consist of arcuate surfaces that are disposed adjacent to one another around a die

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to form, which is received between the prongs.

The prongs are arranged so that they are generally perpendicular to the direction of extension of the cable at a point adjacent to the cable and the die becomes more general Brought into alignment with the contact, followed by relative movement between the die and the contact towards each other completely drilling the prongs through a conductor part of the cable, bending the prongs under the control the die-bending surfaces away from each other and in an opposite direction and the singular grip of the bent prongs with a conductor of the cable which is clamped between the prongs and the contact abutment surfaces, wherein at the same time the projections on the prongs are formed and aligned in the direction of the ladder bridge. When the cable Including layers of insulation on both sides of the conductor, the only pressing process forces the prongs to be pierced through the insulation layers, the penetration of the bent prongs back into a layer and the penetration of the contact surfaces into the other insulation layer.

The invention is illustrated below with reference to in the drawing Embodiments explained in more detail.

In the drawing show:

Fig. 1 is a schematic plan view of an embodiment of the connecting device according to the invention, which is arranged opposite a press die, the position before the attachment of the connecting device is shown on a conductor of a flat conductor cable;

Fig. 2 is a schematic plan view showing the completed connection.

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In Fig. 1 is an embodiment of a connecting device or a contact 10 for a flexible flat conductor cable 12, this contact being identical in its initial shape

with the contact is that in the German patent specification

(German patent application, our file number 15

from the same filing date). With the press-through or Through the drilling process, the contact 10 is reshaped into the shape shown in FIG. 2. The contact 10 can be completely one Pierce conductor 13 embedded in the cable, at the same time forming a bend or corrugation in the conductor will. The contact 10 may have a solder tab or tab 16 or any other mating contact 16 at one end 14 mates with part of another connector (not shown).

The cable 12 can be any conventional flexible flat conductor cable selected from a plurality of parallel spaced apart There is ladders 13 which are generally ribbon-shaped. These band-shaped conductors are in an insulating film 15 made of a polyester or similar material embedded. Mylar (polyethylene terephthalate), Kapton (a polyamide) and Teflon (polytetrafluoroethylene) are typically used as insulating material. It is understandable that these as well as a multitude of other similar materials is suitable.

To perform the piercing of the conductor 13, are on the other At the end 18 of the contact 10, two prongs 20 are arranged. These prongs are carried and pointed by a base part 21 of the contact a sharpened or pointed end 22. The prongs push aside the insulation of the cable and pierce completely the conductor embedded in it. As will be explained in more detail below, the circumference of the shafts results in 26 both prongs 20 make electrical contact with the conductor 13 when the prongs penetrate through the cable.

Each prong 20 has an elongated shaft 26 and an end 2? on. The end 22 of each prong is preferably through

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the addition of an inner bevel 28 and an outer bevel 30 at the end or distal portion of the elongate Shank 2β sharpened. These bevels are formed in the usual way so that a relatively sharp upper cutting or Pierced edge 32 is formed. Preferably the outer bevel 30 larger than inner bevel 28, i.e., the sharpened edge appears in a direction generally unidirectional from a central longitudinal axis 29 of each prong offset on the opposite prong.

Each prong is outwardly bendable, preferably in a plane passing through the longitudinal axis of the conductor. The plastically deformed Prongs can be brought into contact with the conductor again by going through an upper surface 39 of the insulating material 15 penetrate the flat conductor cable 12.

Preferably there is an abutment for the bent or deformed Prongs are provided to hold the flat conductor cable 12 against the press-fit or penetration of the bent cutting edge 32 to support. For this purpose, there are two abutments 34 on the connecting device intended.

These abutments 34 have a reaction surface 35 which is formed by an inner bevel on the support or abutment arms 50. This inner bevel works with a outer bevel 36 on the abutment 34 together to a to form sharp top edge 38.

This sharp edge 38 of the abutment 34 is at a distance the remaining contact parts arranged so that it penetrates the insulation 15 on an underside 40 of the cable 12 and comes into contact with conductor I3 when the cable is on the ground the re-entry of the bent prongs 20 is pressed against the abutment, as can be seen in FIG.

The force used to bend the prongs 20 into position in which the cable 12 between the end 22 of the prong

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and the abutment 34 pressed together should be so adjusted will result in penetration of the insulating material 15 and contact with the conductor I3, but not necessarily a penetration of the conductor 13 · The cutting edges 32 and 38 can after initial penetration into the cable is generally pressed diagonally against the cable at the pinching points. That is, the pinched part 27 of the conductor moved out of the initial plane of the conductor 13 can be. As a result, part of the conductor becomes I3 firmly clamped by the end of the bent prong and the abutment of the contact.

It is understood that there is electrical contact between the conductor 13 and the contact 10 at several points of contact between each of the bent prongs and the conductor 13 adjacent its top surface 49 and between each of the reaction surfaces or chamfers 35 and the Conductor 13 adjacent its lower surface 3I · The exact Type of electrical contact between the prongs and the conductor and between the reaction surfaces and the conductor change depending on the circumstances. In each case, however, a surface contact, an edge contact and / or a point contact with the conductor is achieved at the various points of contact.

As described above, the result is an electrical one Contact and a mechanical connection between the prongs 20 and the conductor at the openings 24 at which the prongs connect the cable pierced at the beginning. It will be understood that electrical contact can encompass substantially the entire periphery of the Tine 20 takes place.

Thus, when carrying out the present invention, as in the case of the above-mentioned German patent specification, there is an electrical contact between the contact or the connecting device and the conductor at at least six different ones

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Places or zones. Each of the prongs 20 passing through the conductor makes circumferential contact with the conductor and each set of clamping devices makes electrical contact at the top and bottom of the nip thereby formed.

As can be seen from Fig. 2, the sharpened Edge 22 of each of the prongs 20 piercing the conductor deform somewhat when the prong is bent, with the result that that the surface of each inner chamfer 28 is stretched somewhat. This fact makes it easier for the tines to reenter into the cable and at the same time increases the area of the inner chamfers 38, which are necessary for electrical contact with the Ladder is available after the prong has been bent.

In any event, it is desirable that the chamfers 35 and 28 be shaped so that they extend substantially parallel of these surfaces is achieved after bending over the prongs 20 and the deformation of the end face of these prongs. This arrangement gives a "single layer" effect to the part of the conductor which defines the position of the entrapment formed by the contact 10.

The sharpened edges 32 of the prongs 20 piercing the ladder separate a length of the conductor which is greater than the distance between the inner walls 42 of the shafts 26 of the prongs. When the conductor 13 and prongs are squeezed together, the severed portion of the conductor is forced to occupy somewhat less space, with the result that a ladder bridge 44 is formed of that length of conductor. It is understandable that this ladder bridge has to bend or bulge somewhat because it is pressed into the somewhat smaller distance between the prongs. The formation of this conductor bridge 44 according to FIG. With a shape concave downwards results in an advantageous bending of the insulating material 46 and 48 above and below this

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special severed part of the ladder. The tensile and compressive forces generated in the curved insulation are used for prestressing the ladder bridge 44 against the inner walls 42 of the prongs 20.

In addition to the pretensioning effect of the insulating material 46 and 48, that covers the conductor bridge 44, the conductor of the bridge itself result in an additional spring effect, which increases this pretensioning effect.

As will be explained in more detail below, according to the invention oppositely directed jumps 47 are at the Formed prongs that grasp the conductor cable located on the bridge.

A part 45 of the conductor 13 can be between the terminal point and an outer wall 43 of the shank 26 of the prong 20 separated be. As can be seen from FIG. 2, the separated part 45 can be pressed against the outer wall 43, namely as Result of the interaction of the tine and the reaction surface 35.

The abutment arms 50, together with the abutment surfaces 34 are formed, are preferably formed resiliently. For this a pair of resilient arms 50 is provided. This springy Arms are preferably formed integrally with the base portion 21 of the contact and arranged so that the abutment surfaces 34 are pressed against the conductor 13. The spring action generated by these resilient arms further improves the Isolation stripping process on the respective cutting edges 38 and 32 of the reaction surfaces and the bent re-entrances Ends of the prongs when the contact is attached to a conductor.

It can be seen that the resilient arms exert a continuous bias against the prongs after they are bent to form the clamping point, so that a

• A

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tensioned compulsory electrical contact results. In this way there is a permanently biased pair of edges or End faces 28 and 35 * which are arranged opposite one another, to sandwich the corrugated part of the conductor when the contact is attached.

Although the contact 10 shown in the drawings is an elongated Has connection contact ΐβ, it goes without saying that a large number of matching contacts can be formed in one piece with this contact and used in the V / eise, as described in the above-mentioned German patent specification.

It can also be understood that in many cases it is desirable is, the connecting device according to the invention together with an insulating housing (not shown) to create a convenient plug-in arrangement that is in the middle or can be used at the end of a length of flexible flat conductor cable.

It has been found to be advantageous to produce the contact 10 from a copper alloy. Phosphor bronze or others Materials can be used with the same result. It can also be seen that a conventional coating, such as for example with gold or nickel or with another suitable base metal would give satisfactory results.

From the Figg. 1 and 2 is a preferred embodiment of the method of attaching a connector to one Detect cables. The contact 10 is held in a fixed position by a suitable bracket or attachment, the is indicated in section at 64. In this position, the bendable prongs 20, which are arranged at a distance, are initially aligned in such a way that that they are generally perpendicular to the direction of extension of the cable 12 extend at a point adjacent to that cable.

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A die indicated in section at 66 is above the Cable 12 and prongs 20 are arranged in general alignment with the prongs. This die includes bending surfaces in in the form of curved surfaces 68 disposed adjacent one another to form a die 70 which can be picked up between the tines. Like it in Pig. I is the shape of the arcuate bending surfaces 68 such that the final tine shape is determined.

A piercing process is achieved in that a relative movement of the die 66 and the contact 10 is brought about in the direction of one another. A (not shown) ram attached to the die or mounting bracket 64 or a ram is used for each of these parts will.

As can be seen, the single piercing operation is forcing the initial piercing of the prongs by the conductor, as discussed above, and the bending of each prong under the control of the flexing surfaces 68 and re-penetration of the bent prongs through the upper insulation layers and the penetration of the abutment surfaces j54 into the lower Insulation layer. At the same time, the die 70 presses the conductor portion of the cable and the insulation between the Prongs in pressing engagement with the prongs. Simultaneous connections of several conductors can be carried out.

Furthermore, the die serves mainly due to the die nose 70 as a pressing tool for forming the prong projections Wj adjacent to the conductor bridge. In this connection it can be seen that the die nose is provided with square corners 71 and has a lateral extent which is greater than the distance between the initially parallel end faces 72 of the spaced-apart prongs, as indicated by the arrows in FIG is shown and when the tines are under the control

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of the arcuate bending surfaces 68 towards their terminal ends Positions are bent, the die 70 presses or scrapes lower portions of the prongs to be generally triangular shaped projections or tips 47 to form.

The lower end face 73 of the die nose presses the projections in their final depicted positions. In these positions These projections cover the conductor bridge and make contact with the conductor 13.

In practice, a drop nose with a lateral extension was used of 0.71 mm and a tine spacing of 0.63 mm with success used. During the piercing process, the prongs give way up to a certain point when they are bent outwards However, eventually, the aforementioned differences in size lead to the formation of the protrusions with the prongs cut will. A die made of a steel of suitable hardness has been used with success for this purpose.

This results in an improved mechanical and electrical connection at the conductor bridge. In particular, will evasion or relaxation of the isolation that could otherwise affect the quality of the connection (in particular if Mylar insulation is used) clearly prevented by the projections 47, which essentially the Encapsulate the conductor bridge and pinch the material of the bridge in an enclosure defined by the projections 47 and the Web 75 is formed which connects the prongs.

It has been found that the interlayer resistance (is represented by the height from which the die is lowered) of the Anschlußvorriehtungen for a given energy input starts low and remains constant for relatively long times after the preparation of the compound.

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In summary, it can be stated that according to the invention a method and apparatus for connecting a flexible flat conductor cable (or a flexible printed circuit, etc.) that a simple and quick connection option was created of flat conductor cables, resulting in a high quality contact. It can be seen that there are many changes to the embodiment described above can be made without departing from the scope of the invention.

Claims;

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Claims (1)

Claims I / connection device for flexible flat conductor cables, characterized by piercing devices (20) for completely piercing a conductor part (13) of the flat conductor cable (12) at any previously selected point on the flat conductor cable to achieve a first electrical contact between the conductor part (13) and the connection device and Conductor clamping parts (30, Jk, 35) for clamping the conductor part (13) at a location remote from the perforation at the previously selected location, the clamping means having a clamping part (30) arranged at the end of the perforation means (20) and W id he inr I lines (3 * 0 for providing a reaction surface (35) against which the flexible flat conductor cable can be supported when the clamping part (30) comes into engagement with the conductor part, furthermore the clamping part (30) and the abutment means (34) in at least one part (39, 4o) of an insulating cover of the conductor part (13) penetrate at the remote location and here form a second electrical contact between the conductor part and the connecting device, and wherein the piercing means (20) have thickening parts (47) which protrude therefrom and form the first electrical contact. 2. Connection device according to claim 1, characterized in that the piercing devices have two comprise sharpened prongs and that the thickening means comprise projections (47) on the prongs (20), which in Direction are directed towards each other. 509846/0834 Connection device for connection to a flat conductor cable according to one of the preceding claims, characterized in that a contact is provided with bendable prongs (20) arranged at a distance and counter bearing surfaces (35) cooperating therewith have bending surfaces (68) cooperating with the prongs (20) that the bending surfaces (68) comprise curved surfaces which are arranged adjacent to one another and which form a die nose (70) which can be received between the prongs (20) and an extension ( 70), which is greater than the distance (72) between the prongs (20), that the curved surfaces (68) with a relative movement of the die (66) with respect to the prongs (20) of contact with one between the prongs and the Flat conductor cable arranged on curved surfaces, piercing the prongs through the conductor part (13) of the flat conductor cable and bending it gene of the prongs into engagement with the conductor of the cable, which between the prongs and the cooperating abutment surfaces of the Kontaktesy'Dew'irke ^ and that the die nose (70) forms projections (47) on the prongs (20) during this relative movement, whereby a portion of the conductor is pinched between the prongs. Method for connecting flat conductor cables, characterized by the steps of arranging a Contact with spaced bendable prongs and with abutment surfaces that interact with the prongs, and a flexible flat conductor in a position in which the prongs are generally perpendicular to the direction of extension of the flat conductor extend at a point adjacent to the flat conductor, with the arrangement of a die Bending surfaces that cooperate with the tines and with tine pressers in position in general alignment with the prongs and the adjacent flat conductor parts, the relative movement of the die and the contact 509846/0834 in the direction of each other to achieve a complete perforation of the prongs through a conductor part of the flat conductor cable, bending of the prongs under control of the bending surfaces of the die generally towards one another on and in an alignment with a direction of extent generally opposite to the original direction of extent, an engagement of the bent prongs with a conductor of the cable between the prongs and the co-operating abutment surfaces of the contact is clamped, and a compression of the lower parts of the Prongs to form prong protrusions that form the ladder section pinch between the tines. 5. The method according to claim 4, characterized t, that the prongs are arranged so that they essentially encapsulating and pinching the conductor between the prongs. 509846/0834