US3428740A

US3428740A - Flat electrical conductor terminal

Info

Publication number: US3428740A
Application number: US586326A
Authority: US
Inventors: Arthur Wayboer
Original assignee: US Department of Army
Current assignee: US Department of Army
Priority date: 1966-10-10
Filing date: 1966-10-10
Publication date: 1969-02-18
Anticipated expiration: 1986-02-18

Description

Feb. 18, I969 A. WAYBOER 2 FLAT ELECTRICAL CONDUCTOR TERMINAL Filed Oct. 10, 1966 III A MINIMUM 8 1 i4 {O JINVENTOR.

ATTORNEYS United States Patent Oflice 3,428,740 Patented Feb. 18, 1969 FLAT ELECTRICAL CONDUCTOR TERMINAL Arthur Wayhoer, Livingston, N.J., assignor to the United States of America as represented by the Secretary of the Army Filed Oct. 10, 1966, Ser. No. 586,326

US. Cl. 174-94 Int. Cl. H02g 15/08; H01r 5/08 5 Claims ABSTRACT OF THE DISCLOSURE welding.

The present invention relates to terminal elements for electrical conductors, and more particularly for flat electrical conductors to provide pin-and-socket type connections therefor.

Presently there are few, if any, commercially available electrical connectors designed for flat conductors using pin-and-socket type contacts. However, the problem of mechanically fastening fiat electrical conductors to the terminal elements or contacts used in electrical connectors of the pin-and-socket type has existed since the manufacture of flat electrical conductors began.

Accordingly, it is the primary object of this invention to .provide improved terminal means for fiat electrical conductors and tight solderless mechanical and electrical connections for pin-and-socket type electrical terminals, connectors and the like.

It is also an object of this invention to provide improved terminal means for mechanically and electrically connecting flat electrical conductors to the pin contact elements of pin-and-socket type terminal connectors, and which makes it possible to provide a mechanically and electrically tight connection between the conductor and the contact element therefor without the use of special tools. With this improved terminal means, equipment ordinarily used to make a conductor termination by soldering or welding is not required, thereby making its cational use unlimited.

In accordance with the invention, the terminal end of a flat conductor is deformed for a certain specified length into a cross sectional shape similar to that of the letter U. The portion of the pin contact element to receive the flat conductor is of tubular construction and either circular or flat as may be desired. The deformed end of the flat conductor is inserted into the contact element and the proper depth of entrance is checked by inspection means provided therein. The contact element is then deformed by applying a force perpendicular to the axis thereof at two locations or areas on opposite sides substantially 180 apart within the area occupied by the deformed end of the fiat conductor. This flattens the contact at the area over which the force is applied, thereby gripping the element fiat conductor and deforming it with the tubular contact element. Since normally the sides of the U fold inwardly, the flat conductor assumes a shape which is thick at the edges and thin along the center, with a fold along each edge, and the terminal element is deformed into contact therewith at two levels, that is, the level of the thicker edge portions and the level of the thinner central portion so that the contact connection is stepped. This gives a tighter mechanical joint than has heretofore been possible, and permits the carrying of heavy currents without soldering or welding.

The invention will further be understood from the following description when considered with reference to the accompanying drawing, and its scope is pointed out in the appended claims.

In the drawing:

FIG. 1 is a fragmentary longitudinal view, in perspective, of a hat electrical conductor termination embodying the invention,

FIGS. 2 and 3 are further views, in perspective, of the contact structure of FIG. 1 showing further operational details thereof, in accordance with the invention,

FIG. 4 is a cross sectional view of a portion of the structure of FIG. 3 taken on section line 44 thereof, showing additional features of the invention,

FIG. 5 is an exploded view of the flat conductor and terminal contact element adapted for engagement in accordance with the invention in a manner similar to that of FIG. 1,

FIG. 6 is a further view of the structure of FIG. 5 showing the terminal element and contact in engagement and locked together in accordance with the invention.

Referring to the drawing, wherein like parts throughout the various figures are designated by like reference numerals, and referring particularly to FIG. 1, a flat electrical conductor 8 is deformed for a specified length into a U-shape 9. The contact element 10, with which it is to be engaged and connected, is a sleeve of tubular construction and constituting part of a contact element of a pinand-socket terminal or circuit connection for which the remaining elements are not shown as this type of plug-in connector is well known and useful for small instrument connections. The tubular sleeve is the area of the element 10 which receives the flat conductor, deformed into the U-shape to fit directly within the diameter thereof, as indicated in FIG. 1. The deformed end of the flat conductor is inserted into the contact element to predetermined depth. This may be checked by providing inspecting 'means such as an inspection hole 11 in the tubular spin contact or sleeve 10 at the point where the end of the fiat conductor is to stop.

Referring to FIGS. 2 and 3, the contact element 10 and the inner conductor are flattened or deformed together by applying opposing forces perpendicular to axis of the contact at two locations apart. One location is directly over the open upper side of the U section of the inner conductor while the other location is directly below the bottom of the U section thereof. These opposing forces are applied in sufiicient magnitude to completely flatten the outer sleeve or contact element and the inner conductor into intimate engagement whereby the contact grips the conductor over a considerable area 12 transversely and in length as indicated in FIG. 2.

As shown further in FIGS. 3 and 4, the result of this operation is to flatten the U-shaped conductor and form a folded edge along each side with a longitudinal gap be tween the opposed edges of the fold. This causes a difference in level, or two different levels on said conductor. The outer tubular contact element or sleeve engages the upper level and, to provide a more intimate contact and further mechanical joining of the two elements, it is indented into the gap in that portion of the deformed area which is directly over the gap or longitudinally extending lower level between the two folded edges. The outer contact element is thus flattened to contact the inner conductor at two levels, thereby providing a terminal structure which mechanically fastens the inner conductor to the tubular outer contact element securely and with low electrical resistance, without soldering or welding.

Referring to FIGS. 5 and 6, an alternate method of forming a mechanical connection between a flat tubular contact element and the like and a flat electrical conductor is provided in accordance with the invention. In this embodiment the fiat conductor 8A is folded back on itself at the terminal end as indicated at 17. The end 17 that folds is of a length corresponding to the length of the contact element A into which it is to be inserted. In accordance with this construction, the contact element is extended twice the length of the fold 17 and in this example has the shape of a fiat tube which may either be solid-or split longitudinally as shown in the drawing.

The flat conductor 8A, after folding, is inserted into the contact element 10A as indicated in FIG. 6 to the desired length or depth and may be adjusted with the same viewing means as its previously described embodiment. Force is then applied along the entire length of the con tact on opposite sides in two locations, 180 apart as before, and in a direction normal to the plane of the flat conductor 8A and its terminal end 17. The opposing forces applied are such that the tool or instrument used further presses the contact 10A into two

levels

14A and 15A, as before in the preceding embodiment. By providing two levels of contact a stronger and firmer mechanical joint is provided and the electrical conductivity is improved since all parts are in intimate contact and flattened together, as indicated in the cut-away portion of FIG. 6.

From the foregoing description it will be seen that the contact end of a flat conductor may be preformed along its edges for a considerable length longitudinally to bring the edges upward and in spaced relation to form a trough or a generally U-shaped cross-section as noted. Thus the conductor may be circular to fit the tubular contact member or be U-shaped with a fiat bottom U, or folded at the end in any way suitable to effect a two level contact structure when suitably deformed within the tubular outer contact element. This design helps solve the problem of mechanically fastening fiat electrical conductors to contacts used in electrical connectors of modern design, which are generally of the pin-and-socket type. Funthermore, this termination makes it possible to make a secure mechanical joint without use of solder or other holding means and by use of a simple tool or like element for applying pressure to the contact on opposite sides thereof as described. This eliminates the need for machines or electrical equipment generally used to make a termination by soldering or welding in the field, and hence permits unlimited use in the field or as may be desired.

I claim:

1. A fiat electrical conductor termination comprising in combination, a flat electrical conductor having a term'inal end folded over on itself and providing two different contact levels along and on one side of the conductor, and a sleeve-like terminal element surrounding said terminal end of the conductor in contact therewith along both of said contact levels to provide locking engagement and finm electrical connection therewith.

2. The combination of a fiat electrical conductor having a folded terminal end providing fiat contiguous contact areas at two different levels on one side thereof, and a terminal element having a sleeve portion surrounding and engaging said folded end of the conductor in intimate contact at both contact areas and levels of said conductor, thereby to provide a relatively-tight electrical and mechanical connection between said conductor and the terminal element.

3. A fiat electrical conductor and terminal combination as defined in claim 2, wherein said end of the conductor is folded on itself along opposite edges, and wherein the sleeve portion is shaped to conform thereto in contact with the first level along the folded edges of said conductor and in contact with said side of the conductor between said folded edges at the second level.

4. A terminal structure as defined in claim 2, wherein the sleeve portion is compressed intermediate between its ends in a limited area in registration with both of said contact levels and into close engagement with the higher one of said contact levels, and wherein said sleeve portion is further compressed in a more limited area within said first area into close engagement with the lower one of said contact levels.

5. A terminal structure as defined in claim 2, wherein the sleeve portion is compressed at the forward end into engagement with the higher one of said contact levels and into engagement with the lower one of said contact levels at the rearward or conductor end thereof, thereby to provide firm attachment of the terminal element with said conductor.

References Cited FOREIGN PATENTS 7/ 1946 Great Britain.

OTHER REFERENCES Wirschitz: German application No. 1,124,121, pub. Feb. 22, 1962.