United States Patent Inventors Dennis J Enright;
 James H. Bazille, Jr., St. Paul, Minn. Appl, No. 777,714 Filed Nov. 21, 1968 Patented Apr. 6, 1971 Assignee Minnesota Mining and Manufacturing Company St. Paul, Minn.
CONNECTOR 4 Claims, 6 Drawing Figs. I
11.8. C1 339/98, 339/101, 339/113 Int. Cl H01r 11/20 Field of Search 339/97- [56] References Cited UNITED STATES PATENTS 2,097,426 11/1937 Arthur et a1. 339/97 2,857,583 10/1958 Mark1eyeta1..... 339/198 3,150,910 9/1964 Dodd 339/198 3,162,501 12/1964 Mahl 339/98 FORElGN PATENTS 392,174 5/1933 Great Britain 339/99 192,890 11/1964 Sweden 339/99 Primary ExaminerErnest R. Purser Assistant Examiner-Joseph H. McGlynn Attorney-Kinney, Alexander, Sell, Steldt & Delahunt ABSTRACT: A connector for making solderless electrical contact between corresponding conductors of bonded wirepairs each having two parallel conductors.
CONNECTOR This invention relates to solderless wire connectors which, although useful in connecting single wires, are particularly adapted for use with bonded pairs of insulated wires (twinned wires or wire pairs) wherein the two conductors are held. in separated side-by-side parallel relationship by means of a unitary plastic insulating cover surrounding both wires and having a figure 8 or twin-circle cross section such as is commercially available under the trade designation Unipair conductor. These wire pairs come in various wire sizes, e.g. from No. 28 to No. 22 B & S gauge, and ordinarily with a polyethylene or similar plastic insulating covering.
 Connectors for flat multiwire cables have previously been described, for example in U.S. Pat. No. 3,189,863, in which a permanent solderless connection is made possible through the use of thin flat resilient bifurcate contact elements which penetrate and displace the plastic insulating cover and make resilient permanent contact with the conductor which is held between the two opposingjaw members.
 The present invention similarly employs resilient bifurcate contact elements but in addition includes provision for orienting the wire pair in position to assure the desired interconnection and for separating the wires prior and subsequent to contact with the contact element. The invention thereby makes possible the splicing together of corresponding conductors of the several-wire pairs in a minimum of time, to produce a fully insulated connection.
 In the drawing, which illustrates one preferred embodiment of the invention:
FIG. 1 is a view in perspective of the assembled connector;
 FIG. 2 is a top plan view of the jacket member, with a portion cut away to show detail;
FIG. 3 is a bottom plan view of the cap member;
 FIG. 4 is a sectional elevation taken approximately along the section 4-4 of FIG. 3;
 FIG. 5 is a sectional elevation taken approximately along the section 5-5 of FIG. 2; and
 FIG. 6 is a front elevation of the connector as applied to two wire pairs.
 Theconnector 10 of FIG. 1 comprises an open-top cuplike jacket member 11 and acap member 12 fitting therein. Anextended front 13 on the jacket 11 is provided with entry ports orchannels 14, 15 to receive the two wire pairs which are to be interconnected. Indicia suchas themarks 16 may be supplied adjacent the entry ports, for example by printing, embossing, molding, or by covering with a decal, to indicate the disposition of the wire-connecting structure within the connector. Typical dimensions for a connector and useful in connecting two wire pairs having wire sizes of No. 22 to No. 26' or No. 28 gauge may be approximately 0.58 inch in length, 0.52 inch in width, 0.33 inch in height in the open condition shown in FIG. I and compressing to 0.24 inch in height when applied to the wire pairs as shown in- FIG. 6. The base and top are constructed of resiliently rigid polymeric insulating material, a preferred material being Lexan polycarbonate resin. A clear transparent resin may be used, thereby permitting a view of the completed connection, or the resin may e.g. be pigmented with colored powders, or blended with flame retardants, or otherwise modified. A high degree of rigidity is desired, but suflicient resiliency is required to permit snap closing of the connector body.
 The jacket 11 is shown in FIGS. 2 and 5 to be in the shape of an open-topped rectangular cup, theextension 13 forming a handle. The bottom of the cup is deeply longitudinally grooved between the end walls to providegrooves 17, 18 and transversely slotted to providediscontinuous slots 19, 20. Elongaterecesses 21, 22 are provided adjacent the sidewalls for a purpose to be described and additional cavities are provided wherever suitable, for reducing the thickness of the section and thus to help in preventing shrink marking;
 Extending along the bottom of the cup or jacket I I from the bottom surfaces ofthewire channels 14, I5 are roundedwiresupporting surfaces 25, 26, 27, 28. The inner surfaces are separated by acentral barrier wall 29; the inner and outer surfaces are separated by thegrooves 17, 18. Thetransverse slots 19, are of the same depth as the grooves, as shown in FIG. 5, and extend in each instance from one groove to the ad- 5 jacent elongate recess and from the other groove to and partly through the central barrier wall.
 The twincircle wire channels 14, 15 flare outwardly to provide wire-accepting flaredopenings 31, 32. The two circular openings of the wire channels are separated bylower ridges 33, 34 and opposingupper ridges 35, 36. The space between upper and lower ridges is just sufficient to permit entry of the connecting web of a wire pair, the two insulated wires then fitting within the circularly cross-sectioned portions of the wire channels. FIG. 6 illustrates the position of a set ofwire pairs 37,38 in thechannels 14, 15 respectively.
 The inner surfaces of the walls of the jacket 11 are slightly flared inwardly to a brokenperipheral peak line 39 of minimum diameter, thereby providing for a snap fit with thecap 12.
 Thecap 12 in FIG. 3 is seen inverted from its normal position atop jacket 11 as shown in FIG. 1. The thus exposed inner surface is provided with sharp-edged ridges 41, 42 which fit snugly between the end walls and within grooves l7, 18 respectively of jacket 11. Transversely of the ridges are locatedcontact members 43, 44, themember 43 being further shown in FIG. 4. Each contact member consists of two resilient doubly pointed slotted or bifurcate contact elements 45, 46 joined by a connectingbridge 47 which is embedded in the plastic cap and is firmly retained by the sharp projectingcorners 48, 49. The slots 50, 51 ofcontact member 43 are aligned with the position of the wire ends on the wire-supportingsurfaces 25, 27 when the cap is placed on the jacket 11. Similar considerations hold forcontact member 44.
 Elongateridges 54, 55 extend outwardly from the side edges of the cap, and analogous extensions may if desired be. provided centrally of the end edges. All four edges of the cap are slightly flared outwardly to form a brokenperipheral peak line 56 of maximum diameter. In the open position shown in FIG. I, theridges 54, 55 fit below thepeak line 39 ofjacket I1 and retain the cap against accidental displacement. The ends of theridges 41, 42 fit against the end walls of the cap to further stabilize the connector in the open position.
 In making a connection, the twowire pairs 37, 38 are thrust endwise into the wire channels l4, 15, which action tends to remove any minor curvatures in the wire ends. The wire pairs are further guided by the edges of theridges 41, 42 centered between the sharp longitudinal edges of the wire-supporting surfaces 25-26 and 27-28 respectively. When the wire pairs are fully inserted, the cap is forced into the closed position, with its top flush with the edges of the cuplike jacket as seen in FIG. 6. The closing operation is conveniently performed with conventional parallel jaw hand-operated pliers. The sharpedgedridges 41, 42 cut through the plastic central connecting web of the wire pairs, forcing the individual insulated conductors into position on their respective wire-supporting surfaces. The upturned sharp edges of the wire-supporting; surfaces deflect the separated wires into their intended positions. The bifurcate contact elements then further center the wires, penetrate and displace the insulation, and make permanent resilient contact with the conductor. Theridge 56 snaps past theridge 39 only on application of force sufficient to assure proper separation of the wires and application of the contact elements. Theridges 54,55 are received in therecesses 21', 22 respectively. Theridges 41, 42 and thewall 29 serve to isolate the several wires and to assure that electrical flashover between unconnected wires is prevented.
 It will be apparent that the structure may be laterallyv extended to accommodate additional wire pairs the individual conductors of which may then be connected in any desired order or combination. Another modification involves lowering of the end walls and removal of the upper half of theextension 13 in alignment with one or more of the wire pair positions, thereby permitting one or more of the wire pairs to be inserted in the connector at a location intermediate the ends of the wire pair, i.e. to produce a tap or bridged connection. In such configuration the wall segments and the upper portion of the front extension may be incorporated in the cap structure so that the ability of the connector to completely contain the connection area may be preserved. in a further modification a wire-receiving extension may be placed at each end so that wires or wire pairs may be introduced from opposite directions; and various other structural modifications and combinations may be made. Partially filling the connector with an insulating waterproof paste, e.g. silicone grease, prior to assembly renders the final connection water resistant without in any way decreasing the effectiveness of the electrical connections.
 An incidental advantage of the structure illustrated in FIGS. 25 is that the 'cap 12 is symmetrical and may be placed with either end toward the wire-entry end of the cup 11. The extended sidearms 54, 55 retain the cap firmly in the open position, and the structure is further stabilized by contact between the ends of the sharp-edgedseparators 41, 42 and the end walls of the cup. There is provided an easily assembled, wellstabilized connector with which permanent safe connections between wires or wire pairs may easily and quickly be made.
We claim:
 l. A wire connector adapted for connecting together corresponding wires of at least two twinned-wire wire pairs, comprising in combination:
a cup-shaped jacket member havlng a series of generally parallel elongate wire-supporting surfaces, one for each wire of each twinned pair of wires, ridged to form a continuous ridge between adjacent pairs of wire-supporting surfaces, deeply grooved to form an open groove between the two wire-supporting surfaces for each said pair, and slotted transversely of said grooves to form aligned slots across corresponding wire-supporting surfaces of adjacent pairs;
said cup-shaped member being further provided, for each of said adjacent pairs of wire-supporting surfaces, with access openings aligned therewith and having an interconnected double circle cross section; and
a cap member, forcefully insertable within said jacket, carrying extended parallel sharp-edged separator plates in line with said grooves and electrically conductive resilient flat thin contact elements in line with and extending along said aligned slots, each said element being slotted in line with one set of said corresponding wire-supporting surfaces.
 2. A wire connector as defined in claim 1 wherein said cap is stably supported on said jacket with said separator plates aligned with said open grooves and adjacent said wire-supporting surfaces for guiding wire pairs into position for interconnection.
 3. A wire connector as defined in claim 2 and having a wireentry extension containing wire-receiving channels forming said access openings in alignment with said wire-supporting surfaces.
 4. A wire connector as defined in claim 3 and wherein said wire-entry extension carries indicia for indicating the position of said contact elements.