US2629763A - Electrical connector - Google Patents

Description

Filed Sept. 16, 1950 3 Sheets-Sheet 1 2 3 J. c. MACY 2 2 ELECTRICAL. CONNECTOR I N VEN TOR.

James C Macy BY A TTOIZIVEYS Feb. 24, 1953 J. c. MACY 2,629,753

ELECTRICAL CONNECTOR Filed Sept. 16, 195a s Sheets-Sheet 2 E filin Feb. 24, 1953 J. c. MAcY 2,629,763

I ELECTRICAL CONNECTOR Filed Sept. 16, 1950 s Sheets-Sheet s INVENTOR 68 J6 JIM/ax: 6 Ma ATTORN Y5 Patented Feb. 24, 1953 2,629,763 ELECTRICAL ooNNEo'roR J a Ma W s fieid, N. J., a i nor o A craft-Marine Products Inc., Harrisburg, Pa,

Appiication September 16, 1950, Serial No. 185,221

2 Claims.

This invention relates to connectors for wires, cables and the like and particularly to improvements in connectors of the type which comprise counterpart terminals having respectively, when connected, interengaging clips.

In the connectors shown in Watts Patent 2,478,1 i3 a blade part of each terminal is formed by a direct continuation of one side of a ferrule by which the respective terminal is secured to and electrically connected with a wire; and the clip part of each of the terminals is formed from an integral lateral extension of the blade and is of substantially uniform width. Since the two terminals have to be brought into an angular relation to each other when assembling, the clip design necessitates a somewhat greater spacing of the clip part of each terminal from the ferrule thereof than the mere width of said clip in order to permit the angular movement of the terminals required for the interengaging of the two clips and blades. The present invention has as one object the reduction of this excess length with corresponding reduction in weight and expense.

The present invention further aims to provide an improvedconnector construction which, without undue increase in length, will provide a stop for the end of the conductor or cable, etc., inserted in the ferrule; andwhich will also-prevent substantial endwise movement of the terminals 0 relative to each other when in their assembled condition; and which will also providea rubbed pressure contact which both improves electrical conduction and adds security to the mechanical connection.

The invention aims further to provide a construction of the terminals such that, in their assembled condition, their ferrules and the enclosed conductor ends can be in substantially .axial alignment with, or other desired relation to, each other, thus making a better appearance and requiring 1ess spaceat the connection than would be the case if they were substantially ofiset laterally.

Other objects and important features of the invention, to which reference has not been made hereinabove, will appear in the following description and claims.

Although in the accompanying drawings 1 have shown a preferred embodiment of myin; vention and have described the same and various modifications thereof in this specification, .it is to be understood that these are notintended to be either exhaustive or limiting of the invention, but, on the contrary, are chosen forthepurposes 2 of illustrating the invention in order that others skilled in the art may so fully understand the invention, its principles and the application thereof, that they may embody it and adapt it in numerous forms, each as may be best suited to the requirements of its particular use.

In the accompanying drawings:

Figure l is a side elevation of a pair of connectors embodying the present invention in assembled or interconnected condition;

Figure 2 is a plan view;

Figure 3 is a section on the line t 3 of Figure 1;

Figure 4 is a view similar to Figure l of a modified form or the invention;

Figure 5 is a view similar to Figure 2 but of the connectors shown in Figure l;

Figure 6 is a side elevation of a connector illustrating another embodiment of the invention;

Figure 7 is a view of the connector of Figur 6 taken looking upwardly from below;

Figure 8 is a side elevation of a pair of connectors of the embodiment shown in Figure 6 but after they have been crimped onto conductors and as they appear when being interconnected;

Figure 9 is a side elevation of the connectors of Figure ,8 when fully interconnected and also showing part of a length of insulating tubing env o i th o ne tio Figure 10 is a view of the connectors of Figure 9 taken looking upwardly from below;

Figure 11 is a view similar to thatof Figure 6 but showing still another embodimentpf the invention;

Figure i2 is a view of the connector of Figure .1 take leas n pw d from below;

Figure l3 is a viewf'sii'nilarto that of Figure 11 but showing the connector crimped onto a conu l. H V

Figure 14 is a perspective view of another form of terminal embodying the invention;

Figure i5 is a side view of the terminal shown in Figure lginterconnected with a connector of the typeillustrated in Figure 8; Figure i6 is a perspective view of yet another form of connector element embodying the in,-

vention;

Figure 17 is a view partly in section illustrating multiple fi i nit embodying the invvention ;v and Figure 18 is a viewsimilar to that of Figure 17 but illustrating a different partial cross section through the unit.

In the firstillustrative embodiment of them-- vention, each of the terminals of the present invention is a counterpart of the other and comprises a ferrule 2, and a tongue or blade portion 4 extending from one side of said ferrule but bodily offset to bring the respective ferrules of the two connectors into alignment. This leaves a bent-over or shoulder portion 6 extending over the outer end of the ferrule. The blade portion 4 of each terminal has an integral extension bent over the end of the tongue to form the clip 8, the blade portion 4 of each terminal acting as a receptor which is received between the blade and clip portions of the other terminal in the assembled connection.

The maximum width of the clip 8 on each terminal is at least substantially equal to or only slightly less than the distance between the inner edge of the clip 8 and the shoulder or abutment 6 so that, when the two terminals are in the assembled relation shown in Figure 1, the clip of one will fit substantially between the clip 8 of the other terminal and the shoulder 6 thereof. The end of the blade 4 and/or the clip 8 is curved, as shown at I0, so that it can cam against the shoulder 6 of the other connector to bring the parts into the intended relation when they are swung from perpendicular to aligned relation. The shoulder 6 serves to limit passage of wire beyond the ferrule 2 so as to prevent interference by such wire with the proper interconnection of the terminals.

As in the connector of the Watts patent hereinabove referred to, connection or disconnection of the two terminals which make u the connection requires movement thereof into an angular relation (se also Figure 8), approximately perpendicular relation in the case shown, before they can either be connected or disconnected. It will be seen that disconnection cannot be effected merely by an endwise pull or by an endwise push or by any ordinary lateral strain and that therefore the terminals are securely interlocked against unintentional separation.

The clip 8 adjacent the bend where it is attached to the blade 4 is spaced a distance accurately equal to the thickness of the blade. Beyond the bend the blade and clip normally converge so that, when assembled as shown in Figure 3, the blade is gripped with a compressive force resulting from deflection of the clip 8. This aspect of the construction is more particularly described and is claimed in the Watts patent aforementioned.

If the length of the clip 8 and the form of the cam face [0 are accurately controlled, the cam face will make pressure contact against the shoulder 6 sufficient to scrape into the oxide surface layer and give a low resistance electrical connection. This arrangement, which is shown in Figures 4 and 5, has the further advantage that the cam first springs the shoulder bend 8a and then, as the point l2 of longest radius moves in from the edge, the resilient pressure on the cam holds the connectors latched together.

With the arrangement shown in Figures 4 and 5 it is important to have the blade 4a and the bend at which it joins the ferrule accurately formed, so that no part of the bend tends to hold the clip 8a away from the blade. To this end the edges of the clip and/or blade are rounded as indicated at 14. With space allowed, as shown in Figures 1 and 2, the forming at the bend can be less exact. In any event the bend sets a limit to the extent to which the cylindrical conformation of ferrule 2 may merge into and run along the blade portion. If good face-to-face contacts between clip and blade faces of two interconnected terminals are to occur then the receptor part of the blade should be planar, and free of any merging into cylindrical shape adjacent the ferrule as may occure with the unbent terminal disclosed in the Watts patent.

The clip is shown in Figures 4 and 5 on the same side of its blade as the shoulder 6a formed by the bend in the blade. This has the advantages of bringing the cam pressure directly on the end of the blade, and of bringing the shoulder 6a farther across the end of the ferrule 2 to give a more effective stop for limiting insertion of a wire therein. With the relationship illustrated in Figure 5 the two aligned clips are held under a slight lengthwise compression between shoulders 6a; this compression tends to maintain the locked relationship because, in effect, the parts have been moved past a dead center across which they must be returned to permit unlocking. At the exact dead center lengthwise compression on the clips between shoulders 6a is, of course, a maximum. A satisfactory connection is made, however, with the clip bent to the opposite side, as shown in Figures 1-3.

Another embodiment of the invention is illustrated in Figures 6-10. As best shown in Figures 6 and 7, the terminal includes a blade portion 20 provided at its outer end with a clip 22 and at its inner end with a shoulder portion 24. In this embodiment the ferrule, generally indicated by 25, is of the composite laminated construction disclosed and claimed in Buchanan Patent 2,379,567. It comprises a split cylindrical ferrule part 26 integral with shoulder portion 26 and a thin cylindrical seamless sleeve 28 of suitable metal, such as copper, telescoped over the split cylindrical ferrule part with a snug fit as shown which holds the pieces in permanent assembly. The cylindrical sleeve 28 extends beyond the ferrule part 26, to the left as viewed in Figures 6 and 7, so as to be in a condition to embrace a substantial end portion of the insulation sheath of the conductor to which the terminal is later crimped, as illustrated in Figures 8 and 9. In the illustrative embodiment of Figures 6-10 the seamless sleeve 28 per se is of the type described and claimed in Carlson et al. Patent 2,405,111 and preferably is made by the process described and claimed in Carlson et al. Patent 2,468,169.

The end of the clip is provided, as by a swedging operation, with a region of clearance 30. The purpose of this region of clearance is for facilitating easy assembling of two terminals (see Figure 8). As pointed out in Watts Patent 2,478,143 and also in the description above of the terminal of Figures 1-3, the distance (see Figure 7) from the lowermost surface of overhanging clip 22 to the opposing upper surface defined by the outer end of blade portion 20 is less than the thickness of the blade. So when two terminals are properly interconnected the shank or receptor part of the blade of one terminal will be grasped between the clip and the outer end of the blade of the counterpart terminal. The clearance region 30 facilitates assembling two counterpart terminals because it enables the receptor part of the blade of one terminal to make an easier entrance into the receptacle-forming space between the clip and the outer end of the blade of the counterpart terminal. As pointed out above, face-to-face contact can best be accomplishedif the blade portion ,4, 20, etc., be-

tween the shoulder and clip which for-ms the receptor part of the terminal is maintained in planar condition. The receptor part of the blade is assured a planar condition by the abrupt bend which forms the shoulder because the bend not only eliminates any merging of the cylindrical configuration oi the ferrule into the receptor part but also injects a region which may bend first under forces perpendicular to the planar faces of the receptor so that the receptor tends to remain flat even during prolonged hard use.

In Figure 8 a pair of terininals are illustrated one being crimped onto the end of an insulated electrical conductor 32 and the other being crimped onto the end of an insulated electrical conductor 3Q. It is to be observed in each instance that the end of the seamless sleeve 23 which extends beyond the ferrule part 26 is telescoped over the end of the insulation sheath of the electrical conductor and there compressed in place so as to form an insulation support. The other end of the cylindrical sleeve 28 along with ferrule part 25 is crimped solidly on the stripped end of the electrical conductor so as to make a permanent electrical contact. The type of crimped connection illustrated in Figure 8 is the one impressed by the normal use of the tool disclosed and claimed in Carlson Patent 2,359,083, which simultaneously secures the insulation-supporting part of the ferrule over the end of the insulation sheath of the conductor and permanently crimps the contact-forming part of the ferrule to the stripped end'of the electrical conductor.

Figure 9 illustrates the present invention embodied in a pair of interconnected terminals enclosed within a removable piece of seamless insulating tubing 3% similar to that illustrated in Figure 1 of Watts Patent 2,478,143. It will be appreciated that when a piece of seamless tubing is slipped over a pair of interconnected terminals, extending from one end of the interconnection to the other, it is not possible to move the terminals from the relationship illustrated in Figure 9 into the relationship illustrated in Figure 8, and accordingly that the terminals must remain locked together so long as the tubing is in place. In order so to lock the terminals -the length of tubing is slipped over one of the terminals to a location along the length of the electrical conductor and the terminals are then interconnected in the ordinary manner (see for example Figure 8). Thereafter the length of tubing is slipped along the electrical conductor toward the connection until it embraces both of the interconnected terminals within it.

It is to be observed that when a terminal is crimped as illustrated onto the end of an electrical conductor, the crimped contact-forming portion of the ferrule which includes the ferrule part 26 has the greatest overalltransverse width of any portion of the terminal. If the insulating tubing is of the semi-elastic type commonly employed for insulation, such as an extruded vinyl chloride compound tubing, which inherently tends to assume its original circular cross section whenever flattened, the ferrule portions of maximum width engage the inner faces of the tubing when the tubing tends to'return from its flattened configuration to circular cross section and thus the flattened ferrule portions oifer a resistance to longitudinal movement of the tubing. To a marked extent this action locks the tubing in position over the connection.

Figures 11 and 12 illustrate a terminal similar to that illustrated in Figures 6 and '7 except that in this instance the seamless sleeve 28a does not extend beyond the ferrule part 26a of the terminal. In this respect the terminal resembles the composite laminated ferrule shown in Figure '9 of Buchanan Patent 2,379,567 rather than the one shown in Figure 13 of the Buchanan patent where the sleeve extends to form an insulation support in the fashion exemplified herein by the embodiment of Figures 6 and '7.

Figure 13 illustrates the connector of Figures 11 and 12 after it has been permanently crimped onto the end of an electrical conductor. As in the case illustratedin Figure 9, the overall transverse width of the ferrule in the region of the contact-forming crimp is seen to be the portion of maximum "transverse'width. This portion resists longitudinalslippingof an insulating tubing corresponding to the tubing 36 described in connection with the embodiment of Figure 9.

It will be understood with respect to each .of the various embodiments of the invention that the contact-forming crimped portions of the "ferrules will serve to hold a piece of insulating tubing in position enveloping the interconnectionand that so long as the tubing is held inpplace the interconnected terminals cannot be disconnected. And in each instance the shoulder portions 6, 24, 24a, etc., prevent appreciable lengthwise movement of one terminal with respect to its counterpart so that relative longitudinal movement of the interconnected terminals .cannot work an enveloping insulating tubing 01f .of locking position on the connection.

In eachof the foregoing specifically described embodiments of the invention the terminal has included some formof ferrule. Figure 14 and 15 illustrate another typeofterminal generally indicated at 4b. In the embodiment herein described, terminal M3 is formed from sheet metal by metal stamping andbending operations and embodiesa channel-likeconnecting.end indicated at 42 and a ring tongue end-indicated at MS. Tongue M is intended to be positioned overa threaded binding post in conventional fashion and there locked in place by anut. Connecting end 62 includes a blade-like portion 36 provided toward its .outer end with an integral clip 48 bent over'through approximately from the upper outer longitudinal edge of the blade. Between blade portion 4'6 and tongue'M the terminal is provided with a shoulder portion to spaced from the nearest edge of clip 48 as measured longitudinally along blade portion l-fi by an amount only slightly greater than thelongitudinal width of the clip.

Thus a connector of the type describedin relation to Figure 8 may be interconnected with terminal 4i! inthe same manner that the two connectors described in relation to Figure8 were interconnected.

When terminals of the type illustrated in-Figures '14 and 15 are available, an electrical connector of the preceding types illustrated and described'herein may be brought'into electrical engagement withan ordinary binding post so that electrical systems embodying my invention mayreadily *be'assembled'asparts of larger sys- "tems embodying more conventional connectors. .It will be appreciated, of course, that the clip, blade portion, and shoulder portion of the terminal illustrated in Figures 14 and 15 perform the same equivalent functions as are performed by the corresponding parts of the connectors previously described herein.

Figures 16, 17 and 18 illustrate the present invention embodied in a multiple connector block such as is disclosed in Figures 17-21 of my application Serial No. 631,031 filed November 27, 1945, now Patent No. 2,545,429, issued March 13, 1951; for a more complete disclosure of this type of multiple connector block reference may be had to said application. The conducting element of the connector block is indicated generally in Figure 16 at 52. Element 52 in the illustrative form is formed from sheet metal by stamping and bending operations and incorporates a central conducting portion 54, a pair of shoulder portions 56 and 58 located at each end of the conducting portion, a pair of blade portions 60 and 62, and at each end of the element an integral clip 64, 65. The clip and shoulder and blade portions of element 52 are shaped to perform the same functions as the clip and shoulder and blade portions of terminal 40 and of the preceding connectors described hereinabove. connector of the type illustrated in Figure 8 may be interconnected at either end of element 52 with the clip of the connector in face-to-face contact with the blade portion of element 52 and constrained against longitudinal movement in either direction along the blade portion by the abutting faces presented by the clip and the shoulder portion.

Figures 17 and 18 illustrate the use of a plurality of elements 52 locked in parallel disposition within a connector block fashioned from insulating material. The connector block comprises a central disk 58 provided with radial slots, each slot being fitted to receive the intermediate portion 54 of an element 52. As shown in Figure 18 a pair of insulating cores l and 72 are clamped in back-to-back relationship upon the center of disk 03 by an axially disposed rivet (4. Each of these cores is provided with radially extending clearances aligned with the radially extending slots of disk 68 fitted so as to afford access to the end portions of the elements 52 and so as to form insulating barriers between adjacent end portions. As pointed out in greater detail in my copending application, the intermediate portion 54 of each element 52 is molded or otherwise permanently secured within its individual radially extending slot so that its end portions are maintained in fixed position within the respective fitted clearances provided in cores and 72. Thus, as shown for example in Figure 17, the portion 54 of element 52 there illustrated is fixedly secured in disk 68 with shoulders 56 and 58 in abutment against the opposing flat surfaces of the disk so as to reinforce element 52 against longitudinal movement within the radial slot in which it is held. The end portions of elements 52 function in the same manner as the end portions of any of the abovedescribed interconnectors embodying my invention.

The opposing ends of each of the elements 52 may be made accessible, so that connectors of the type illustrated in Figure 8 for example may be interconnected with them, by removing the spring clips 76, 78, 80 and 82 and disassembling the insulating surrounding semi-cylindrical shells indicated at 84 and 86. After the connections have been made they may be locked against accidental disconnection or protected against short Thus a circuits by restoring the insulating shells 8| and 86.

From the foregoing it is apparent that the connectors, terminals and connecting elements de scribed above are well suited to attain the ends and objects herein directly and indirectly set forth, and that they can be manufactured easily by conventional fabrication techniques, and that the various features and arrangements of parts can be modified readily so as best to suit a particular use. Certain features of the disclosure may be used to advantage in particular applications without a corresponding use of other features, and the elimination or modification of such features is to be construed as within the scope of this invention unless specifically excluded by the following claims or required by the scope of the prior art.

I claim:

1. A connector comprising a ferrule for connection to a circuit element, a strip-like blade of substantially uniform thickness extending freely therefrom, a clip on a portion of the blade remote from the ferrule, one face of said blade to ward the free end portion thereof being planar for a distance back from the free end at least about twice the corresponding dimension of said clip, said clip extending integrally from a lateral edge of said end portion and across said planar face with spacing therefrom which, when the connector is unconnected, is slightly less than the thickness of the blade, and a bend on a straight line across the strip-like blade between the ferrule and the end portion forming a guide for engaging the end of a counterpart connector during connection to hold its clip portion within the region surrounding said planar face.

2. A connector comprising a ferrule having a blade extending from one end thereof, said blade being bent adjacent the ferrule to offset the remainder of the blade so that one face thereof is substantially on an extension of the axis of the ferrule, a clip on a portion of said blade remote from the bend, said clip extending from one lateral edge beyond said axial face and back across said face with spacing therefrom which, when the connector is free, is slightly less than the thickness of the blade, said clip being formed from an ear extending integral with the blade, extending laterally therefrom and folded back upon the blade through at least degrees, and the length of the blade portion between the clip and the bend in the blade adjacent the ferrule being at least as great as the corresponding dimension of the clip.

JAMES C. MACY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,104,436 Menningen July 21, 1914 1,225,127 Heath May 8, 1917 2,021,701 Smith Nov. 19, 1935 2,450,202 Macy Sept. 28, 1948 2,453,615 Bergan Nov. 9, 1948 2,478,143 Watts Aug. 2, 1949

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