DE2321041A1 - ELECTRIC CLAMP WITH ONE PIN FOR WIRE WRAPPING CONNECTIONS - Google Patents

Description

SCANBE MANUFACTURING CORPORATION, a California company located at 3445 Fletcher Avenue, El Monte. California 91731 (V. St. A.)

Electrical clamp with a pin for wire wrap connections

The invention relates to free-standing electrical terminals, and more particularly to a free-standing electrical terminal having a Socket and a pin for wire wrap connections.

According to the state of the art, many electrical connections are made using automatic machines, that wrap a bare electrical conductor around an electrically conductive pin, around an electrical one To achieve transition. This type of connection is known as a solderless wire wrap connection. The one to be wrapped Pin is usually in a printed circuit board or similar electrically insulating substrate attached. The pin is usually designed as a solid element so that it winds up when it is tight of the electrical conductor can withstand forces. With the growing use of integrated circuits the wrap-around pins for the production of electrical

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ORIGINAL INSPtOTiQ

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shear contacts with the integrated circuits with receptacles equipped for the integrated circuits. The electrical conductors of the integrated circuits are usually miniaturized; They can be round or flat conductors, which make an electrical very difficult Can connect. For this reason, electrical circuits are usually in a socket terminal attached, which has a socket for receiving the conductor of the integrated circuit, and with a Pin is connected, which allows the production of the wire wrap connection.

The usual electrical terminals with receptacles for electrical circuits are of a two-part construction with a tubular part and a solid pin-shaped part for winding up the conductor wire. The tubular part is used to receive the lead wires of an integrated circuit and to manufacture one Press fit in an insulating support. This prior art two-piece clamp is commonly used manufactured on screw manufacturing machines. This kind of the electrical terminals has proven to be extremely satisfactory from a functional point of view; she is the most popular of the commercially available free-standing clamps. However, this two-part construction is expensive to manufacture and can do not easily insert themselves into the carriers by means of automatic machines. The two-part according to the state of the art Terminals are traded loosely; for automatic insertion in a carrier they must therefore be on a carrier strip lined up or fed by vibratory conveyors or discharge conveyors. This type of installation is expensive; It has also been found that compared to the automatic insertion technique using a carrier strip integrated with the electrical terminals, the vibratory conveyors work unreliably. Extensive efforts have been made to educate

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Ligere constructions for receiving sockets for integrated Circuits or the like. to develop, in particular, to address the need for the manufacture of electrical terminals on screw manufacturing machines, and to enable the automatic insertion of the clamps. The result so far is a commercially available two-part clamp whose wrap-around pin can be used automatically, but whose socket is inserted by hand got to. The two-part construction creates reliability problems; and manual insertion required the socket partially offsets the advantages of the automatic insertion of the pin. This type of clamp has an overall length of about 21 mm; thereby it is in printed circuit boards with a thickness of approximately 16 mm can be used. The height of this clamp is a limit height according to the state of the art, clamps manufactured on screw manufacturing machines does not exist. These parts usually have an overall length of about 18 mm.

Despite the attempts, cheaper, technically produced by screw-making machines, To develop clamps that are equivalent to two-part clamps, the user usually had to find out that the Use of the cheaper two-part clamps is almost the same. is as costly as using expensive two-piece clamps since it saves capital investment for the automatic Haschinen must make instead of spending money on prefabricated printed circuit boards with built-in electrical ones Output terminals. Accordingly, there is currently still a commercial demand for freestanding, one-piece electrical terminals with a socket and a wrap-around pin, which are cheaper to manufacture, than the e.g. available free-standing terminals. It is also desirable to have automatic insertion

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the clamps in an insulating support or the like. use to equip these terminals with a carrier strip.

Accordingly, the invention proposes an improved and relatively inexpensive one-piece electrical clamp having a Socket end and a plug end that can be used as a wrap-around pin. The electrical according to the invention Clamps can be manufactured in such a way that they are still held together by a carrier strip at the end of production which can be stored on a reel for use in automatic insertion devices. As a consequence of Significant savings in material costs through the elimination of the massive wrap-around pen can be the electrical terminal according to the invention to a third or half the cost of e.g. commercially available free-standing electrical terminals. The .inventive electrical clamp is also a miniaturized construction with an overall length of approximately 18 mm with the wrap-around stick approximately 13 mm in length. The free-standing according to the invention The clamp is also suitable for holding a conductor of an integrated circuit with a length of at least 4 mm, this is currently the typical length of conductor wire for integrated dual-in-line circuits. At this length the socket sits the integrated circuit on the socket.

In its most general embodiment, there is that according to the invention electrical clamp in an improved design of a wire wrap clamp that works on its own as a terminal for a solderless rocker connection without Use of a solid pen can be used. The wraparound end of the clamp of the invention is off made of a thin, electrically conductive material that is folded and pressed into a hollow structure, making it the state of the art massive

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is mechanically equivalent to wrappable pins. The wrap-around pen of the present invention can be characterized as a folding structure that has the structural rigidity of a box girder. The electrical pen according to the invention has a largely rectangular configuration; its folds are sufficiently close to one another to prevent its deformation by compressive forces resulting from the winding of a bare electrical conductor around the pin to create a solderless connection. The foldable construction of the wraparound pen is created by folding a thin electrically conductive material into a "U", then folding the two legs of the "U" onto itself, and then compressing the resulting configuration. To this end, the electrically conductive material can have a thickness on the order of 0.1 mm instead of the 0.6 mm of currently used materials. The wrap-around pen according to the invention can be combined in one piece with a socket end. The socket end of this free-standing electrical terminal according to the invention can be equipped with a pair of inwardly projecting leaf springs arranged at a predetermined distance from one another for receiving an electrical conductor between them. The leaf springs are formed so that they take up the thin miniaturized conductor wires integrated circuit without difficulty, and without the fine conductor wires permanently deforming. The hollow construction of the socket end allows a plug element to be inserted up to the wrap-around pin, which minimizes the overall height of the assembly for a given pin length.

The invention is described in detail below with reference to an embodiment shown in the drawings. It shows:

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Fig. 1 is an enlarged front view of an embodiment of an electrical terminal according to the invention with a breakable carrier strip shown in dashed outlines;

FIG. 2 is an enlarged, partially sectioned front view of the electrical terminal according to FIG. 1; FIG.

Fig. 3 is an enlarged cross section 3-3 according to FIG. 2 of the plug end of the electrical terminal in which part of the material in the unfolded state is shown in dashed outlines;

Figure 4 is a cross-section 4-4 according to Figure 1 of the socket end of the electrical terminal;

Figure 5 is a side view of the electrical terminal of Figure 1; '■

Fig. 5A is a plan view 5A-5A according to Fig. 5 of the electrical Clamp;

Fig. 6 is an enlarged view of the electrical terminal of FIG. 1 showing the mode of use of the electrical Clamp for holding an electrical device and two types of fastening the electrical Illustrated clamp in an insulative carrier;

Fig. 7 shows a different application of the electrical Terminal according to FIG. 1 in connection with a metallic or electrically conductive carrier Elevation;

Fig. 8 is a longitudinal section of several for use with a plug in an insulating support fastened electrical terminals according to Figure 1; 3 09847/07 68

9 shows an alternative form of arrangement for use of the electrical terminals according to FIG. 1 in a row of insulating and metallic carriers.

According to FIGS. 1, 2 and 5, an embodiment of an electrical terminal 10 according to the invention with a socket end F and a connector end M be equipped. It should be noted, however, that the invention is only constructive Design of the plug end M may concern, or the socket end F to include. The connector end M of the electrical terminal 10 is independent of the socket end F than with wire due to its novel construction Wrapable pin suitable for creating a solder-free connection.

The electrical terminal 10 consists of a single piece of thin electrically conductive material, which with the help of A suitable tool is formed into the clamp 10 by several successive folding and bending operations has been. This manufacturing process allows the clip 10 to be manufactured as a breakaway Support strip 11 hanging integral unit. In Figs. 1 and 2, a two adjacent clamps 10 is connecting Piece of the carrier strip 11 shown. The carrier strip 11 is made of the same material as the clamp 10; it is equipped with a plurality of openings 11a arranged in series in the longitudinal direction. The openings lla can, as shown, be vertically aligned with terminals 10. It is obvious that the electrical Terminals 10 can be stored on a spool by means of the carrier strip 11, so that they can be accessed by means of a high Automatic inserting machines operating at high speed can be inserted into specified carriers. The carrier strip 11 has feed openings 11a, which are used during the manufacturing operations to electrically

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conductive sheet material through the various to manufacture the clamp 10 to move required molding steps and to align the clamps 10 during insertion. During the insertion operation, the carrier strip 11 is sheared off from the point 10 exactly at the point at which it is according to FIG 1 and 2 is connected to tabs 12 arranged at the outer end of the bushing F. The shear operation is carried out by a punch, which is used at the same time to press the clamp 10 into the carrier. It has shown that beryllium-copper sheet with a thickness of about 0.1 mm is particularly suitable for making the electrical terminal 10. Though beryllium copper is relatively more expensive than other materials used to make such clamps, as will be explained later, result from the design of the clamp 10 savings in manufacturing costs.

An essential novelty of the invention is the construction of the plug end M of the terminal 10. The prior art accordingly, wraparound terminal pins are solid to produce solderless connections. This is necessary to avoid deformations of the wire-wrapped pin during the automatic wrapping process caused by the pressure forces acting on the pin are produced could. Accordingly, the structural integrity of such a wirewound pen is of substantial concern to give, since deformations of the pin caused during the winding process are the result of the wrapping of the pin with a bare electrical conductor have a very detrimental effect on the electrical connection made can. The connector end M has a novel construction, as it is hollow inside and so by a Series of predetermined bending and folding operations is formed so that it has the structural rigidity of a massive And is therefore mechanically equivalent. The construction of the connector end M is best shown in Fig. 3 can be seen, which is an enlarged cross-section of the

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Shows connector end M; the male end M is a box-like structure made by folding and bending so that it has a central opening Mo. The box-like connector end M is folded and shaped to have the structural rigidity of a box girder. This construction results from the use of a thin electrically conductive sheet, for example, as already mentioned, made of beryllium copper, the edges of which are bent into a U-shaped configuration as shown in FIG. 3. The two legs of the U-shaped structure formed before the final bending operation are shown in FIG. 3 in dashed outlines; they are identified by the reference symbols M _L and M _R. The legs are then folded in. The inside of the "U" on themselves so that they assume the final configuration according to FIG. 3, in which they _{rest against the unfolded parts of the legs M ^ and M R} and against each other along a seam Touch Mq intimately. This end configuration is then subjected to a final calibration operation, for example die pressing, embossing or the like, in order to compress the folding structure in such a way that the end configuration according to FIG. 3 is produced. During this final calibration operation, the box construction is formed compressively in order to close the seam M ″ tightly and in order to reduce the corner radii 13 to the desired degree of sharpness, which allows a solderless connection to be wound up. As a result of this end operation, the connector end M is simultaneously given its desired dimensions within the specified tolerances. The remaining inner gap Mo allows the compensation of usual fluctuations in the width of the planar shape or the thickness of the material used, so that the end dimensions of the terminal and the plug end M are not influenced by these fluctuations.

It must be warranted that, compared with the high production costs of the "as-

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2321Q4T

siven connector ends the manufacturing costs of the invention wrap-around connector end M by producing the clamp according to the invention as a hollow construction significantly reduced by folding and bending operations could become. Due to the tight packing of the folds that are used to produce the clamp end M, the terminal end M is mechanically equivalent to a solid construction and there are no sharp edges Make burrs. Since the pressure forces applied by automatic winding machines are evenly distributed to the four Edges of the connector end M, which is made up entirely of folds, become deformations caused by these forces prevented. In addition, the beryllium copper used is used during the manufacturing process Hardened by the strong deformations and the heat treatment, so that it has the necessary mechanical properties which are at least twice as high as the mechanical properties of the manufacture the metals used in the prior art terminals. According to the prior art, usually Phosphor bronze or nickel silver alloys are used.

It should be noted that the terminal 10 according to the invention in particular in connection with integrated modules to accommodate the sensitive wires of the integrated modules in the socket end F and to produce a electrical connection with the integrated circuit through the connector end M can be used. The dimensions sn of the commercially available integrated modules a miniaturized construction, the electrical terminal 10, while maintaining good electrical contact with the integrated module is required. For this purpose, the overall length is a practicable one Embodiment of the electrical terminal 10 approximately 18 mm. This overall length is shown as dimension L in FIG. For the same purpose, the 309847/07 6-8

outer dimensions of a connector end M with e.g. a square Cross-section in its final configuration will be approximately 0.5 mm. This outer dimension is identified by the reference symbol S in FIG. 3. The connector end M has a part that can be wrapped around ¥ with a length of about 13 mm. For the same purpose, the tubular part is between the socket end-F and the plug end M of Figure 4 constructed as a hollow box; whose rectangular cross-section is a side length of approximately 1.0 mm.

The socket end F formed by one end of the clamp 10 is inclined with a pair of inwardly extending leaf springs 14 and 15 equipped; the leaf springs 14 and 15 are for receiving and fastening an electrical conductor arranged between them by a predetermined distance from one another. For use with an integrated module, the distance is "O" according to FIG. 2 between the inner ends of the leaf springs

14 and 15 about 0.2 mm. The inner ends of the leaf springs 14 and 15 are with a slight curvature equipped with a radius of approximately 0.1 mm. These rounded ends are denoted by the reference numerals 14R and

15 R marked. It should also be noted that the Leaf springs 14 and 15 extend inwardly in the socket end F relative to the side walls in such a way that they lead electrical conductors with the radii 14R and 15R in contact. The socket end F is also at his Equipped with two tabs 12 at the upper end. According to FIGS. 5 and 5A, the tabs 12 are on opposite sides Sides of the inlet opening of the socket end F offset by 180 ° with respect to the leaf springs 14 and 15. It should also be noted that the leaf spring contacts 14 and 15 of the socket end F according to the invention are designed that the forces exerted on electrical conductors during insertion and extraction in one

extremely satisfactory relationship to each other, 3 0 9 8 A 7/0 7 6 B

and that for receiving electrical conductor wires of the most varied Sizes a deflection of the leaf spring contacts ■ 14 and 15 is possible in a wide range. That is, when a conductor wire is inserted between the leaf springs 14 and 15, they are loosened by the friction of the conductor wire spread apart, reducing the force required to insert the conductor wire will; while when pulling out the conductor wire, the leaf springs 14 and 15 are compressed by their spring action, so that a larger one for pulling out Force is required. This results in various "advantages over the known, commercial use for Available connector terminals. This construction also allows less with conductor wires Make good contact with the terminal, about 2.5 mm long. Furthermore, this construction makes it impossible that a conductor wire penetrates into the socket end F without ge between the leaf spring contacts 14 and 15. long; E.g. dual-inline modules have a special feature thin conductor wires with a minimum thickness of about 0.2 mm, while the gap between a leaf spring and the adjacent side wall is only about 0.1 mm.

The electrical terminal 10 is designed as a free-standing terminal in contrast to a terminal that is in a insulating support must be attached and held in position. Of the clamp 10, only the tubular one is used Part between the socket end F and the plug end M connected to an insulating support. The structural integrity of the clamp 10 is ensured by the inventive Construction of the tubular part guaranteed. According to Fig. 4, its four sides are folded so that there is a seam S only on one edge.

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This construction creates a box girder with a largely closed along the Uinfanges of the clamp 10 Surface without any gap; the seam S is sufficiently tight to allow the solder material to flow in to prevent into the socket end F; The introduction of an electrical conductor wire could result from the solder material flowing in be hindered or made impossible in the socket end F. In contrast, the state of Technically appropriate clamps on one side with only one tab equipped. By selecting the appropriate material for the electrical terminal and the plating, the Terminal with a printed circuit board or the like. solderable. The solderability of the terminal 10 ensures one secure fastening in circuit boards with a thickness of approximately 1.6 or 1.2 mm.

In Fig. 6 to 9 different types of use of the electrical terminal 10 are shown. In Fig. 6 is a pair with spaced apart electrical terminals 10 attached in a circuit board 20. The left clamp 10 is by means of a solder joint and the right terminal 10 by means of an interference fit in the printed circuit board 20 attached. When the freestanding clip 10 is mounted in a printed circuit board 20 in any of these ways is, their wire-wrapped connector end M protrudes downward from the plate 20 that create a solderless rocker connection to it leaves. The plug end F protrudes from the opposite side of the plate 20 so that it is the Can accommodate conductor wire of an electrical component. The modules that can be connected to terminal 10 are shown in FIG. 6 as dual or non-dual inline modules marked. The lead wires of these blocks are in the socket end F between the leaf springs 14 and 15 introduced to make the necessary contact

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between the module and the solderless winding connection.

In Fig. 7 are alternative ways in which the clamp 10 can be used shown; the openings receiving the clamps 10 a conductive support 21 are with. Insulating sockets 22 fitted to the terminals 10 in non-conductive connection to hold the conductive carrier 21. According to the illustration on the right-hand side of FIG. 7 are in this Insert several pins soldered into a printed circuit board, while their free ends into the socket ends F several terminals 10 are inserted.

In a further alternative type of use, several electrical terminals 10 according to FIG. 8 are not free-standing Arrangement fixed in an insulating support 25. It should be noted that the socket ends F completely are arranged in the insulating support 25, while the plug ends M protrude outward. The insulating carrier 25 is equipped on its side opposite the connector ends M with inlet openings 25 I, which Allow contacts to be inserted into the socket ends F located below the surface of the carrier 25. the Clamps 10 can be fixed in carrier 25 by means of their tabs 12.

A further alternative type of use of a plurality of electrical terminals 10 in connection with a plurality of conductive and non-conductive supports is shown in FIG. 9. It should be noted that the conductive carrier 21 carrying the electrical terminals 10 is inserted so that the connector ends M are not used as wrap-around pins but only as conductive connector pins which are inserted into associated terminals 10 of a printed circuit board arranged below. It is also evident that the pins protruding downward from the upper printed circuit board as shown in FIG

can be the M of the clamp according to the invention.

The invention thus consists in a free-standing electrical terminal with a socket end and a plug end that can be wrapped around for making solderless wound connections. The wraparound connector end is a hollow structure formed by bending, folding, swaging, and sizing, of the same structural integrity as a
massive pin.

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Claims (12)

Expectations 1.! Electrical terminal with a plug end for the production ~ y position of solderless nickel connections, characterized in that it is made of a thin electrically conductive material; that the plug end (M) is sufficiently long so that an electrical conductor can be wound around the plug end (M) to establish an electrical connection; and that the plug end (M) is hollow and is constructed by folding and packing the thin electrically conductive material so that it is mechanically equivalent to a solid pin. 2. Electrical terminal according to claim 1, characterized in that the plug end (M) tightly in a largely rectangular configuration is folded and wrapped to avoid deformations of the plug end (M) due to compressive forces to prevent during the winding up of an electrical conductor. 3. Electrical terminal according to one of claims 1 or 2, characterized in that the thin electrically conductive material has a thickness of the order of magnitude 0.1 mm instead of the usual 0.6 mm. 4; Electrical * clamp according to one of Claims 1 to 3 characterized in that the thin electrically conductive material is beryllium copper. 5. Electrical terminal according to one of claims 1 to 4, characterized in that the plug end (M) is constructed and shaped so that it has the structural rigidity of a box girder. 309847/0768 2327041 6. Electrical terminal according to one of claims 1 "to 5 characterized in that that by tightly folding and wrapping the thin electrically conductive material on itself formed connector end (M) by folding at least one leg of the material in the interior of a fold formed along the other leg of the material is shaped. 7. Electrical terminal according to one of claims 2 to 6, characterized in that the largely rectangular Configuration of the plug end (M) is given by the fact that two ends (Μ «Μ.) Of a rectangular Piece of thin electrically conductive material folded on itself and then the folds are packed tightly together. 8. Electrical terminal according to claim 7, characterized in that the plug end (M) is formed in that first the material is folded into a "U" and then the legs of the ⁿ U "(M" M _T ) are folded onto themselves. 9. Electrical terminal according to one of claims 1 to 8, characterized by one of the plug end (M) opposite Bushing end (F). 10. Electrical terminal according to claim 9, characterized in that that the socket end (F) is a pair of inwardly projecting, at a predetermined distance from each other arranged leaf springs (14, 15) for receiving and fastening an electrical conductor in a electrical connection between them. 11. Electrical terminal according to one of Claims 1 to 10 characterized in that it is a freestanding electrical terminal. 309847 / U768 2327041 12. Electrical terminal according to one of claims 1 Ms 11, characterized in that it is a miniaturized Construction with an overall length on the order of approximately 18 mm. 13 · Electrical terminal according to one of Claims 1 to 12, characterized in that several of these terminals
(10) can be inserted into several openings of a carrier (20, 21, 25) at a distance from one another; and that
each terminal (10) is fastened centrally between the socket end (F) and the plug end (M) in the associated opening of the carrier (20, ...) that the two ends (F, M) 'are located opposite one another
Sides protrude from the carrier (20, ...). 309847/0768