US2887667A - Solderless electrical connector - Google Patents

Description

'w. awoLFE Erm.

soLDERLEss ELECTRICAL CONNECTOR FiledvAug. 5, 1955 May 19, 1959 2,887,667

ATTORNEY y I INVENToRj 44 45 ,47 9 5 .5l Fl". 7 fo@ 42 45 5545/ (i1/2 9 Unid. States Patte* xT 2,887,667 y f soLDERLEss ELECTRICAL CoNNacTon fi William E.Wolfe, Philadelphia, and Robert A. Iulorn, i i Doylestown, Pa. j

Application August 5, 1955, Serial No,` 526,601

Our invention relates to electrical conductor terminals,

and more particularly relates to solderless type terminals for shielded and coaxial cables. i t j t The shielded and coaxial cables used as interconnections between electronic devices is usually comprised of a very line stranded or tinsel center lead surrounded by a tubular insulation. tral lead, and over the tubular insulatiomisfastranded wire lead which is used as a companion lead for the cen-l ter lead and a shielding means fory the center lead. Surrounding the coaxial lead andover the entire assembly is a'sheath of insulating material. As it is very diilicult toy make a satisfactory electrical connection to the line center lead of the cable, it is an object offour invention to devise a solderless,` terminal for a coaxial cable that is readily and securely applied to the coaxial cable end.

Another object of ourinvention is to devise a terminal for a coaxial cable that provides positive electrical connection tbetween the current carrying parts of. the terminal and the current carrying leads of the cable.

Another object of our `invention is to devise an electrical terminal for a coaxial cable that provides definite securing of the coaxial lead to prevent movement be` tween the current carrying parts of the terminal and the attached leads and thus prevent destruction of the electrical connection.

, Another object of our invention isto devise an electrical terminal fora coaxial cable having the current carrying elements of the terminal coaxially disposed.

Other objects of our invention are to provide an improved device of the character described, which is easily and economically produced, which is sturdy and compact in construction, and which provides positive and secure termination for the leads of a coaxialror shielded cable. With theabove and related objects inview, our invention consists in the details of construction as hereinafter shall be set forth, and the description will be more readily understoodwhen read in conjunction with the accompanyinezdrawingsiinwhich: 1 y s f f `Fig.l lisfan isometric viewof a preferred embodiment of our improved terminal showing the terminal applied to the leads of a coaxial cable.

Fig. 2 is an isometric view of the female portion of our improved connector shown positioned in the panel of an electronic device chassis.

Fig. 3 is a sectional elevational view taken along the line 3--3 of Fig. 1.

Fig. 4 is an isometric view showing a modified method of securing the coaxial cable to the terminal and making electrical contact to the shielding lead of the cable (cable not shown).

Fig. 5 is an isometric view of the modified method of cable securing showing the securing means formed over the shielding lead of the cable.

Fig. 6 is an isometric view of a modified form of our improved coaxial cable terminal.

LCC

t* limited'- llexing of the contacting shield so that it can` be Coaxially disposedaround `the cen- J i,

pressed onto and have a positive electrical contactwith the'shield of the receptacle portion R, hereinafter described. A shouldered cylindrical portion 12 of the contacting shield 10 is arranged to interfit with a hole 13 W in a handle member 14, the cylindrical portion 12 being expandedv at 12A to fixedly secure the contacting shield in definite space relationship to the handle, generally designated las H. The contact making element 15 of the plugunit Pis cylindrical in shape with a closed semi-spherical end 16. The inner end 17 of the contact makingelement 15 is arranged `to intert with a hole 18 ina disc-shaped insulating spacer member 19. The spacer member 19 is positioned by a shouldered portion 20 of the contacting shield 10 and is secured in place by a portion of the metal that is cut out of the slots 11 in the contacting shield. The metal cut out of the slots is allowed to lremain attached to the contacting shield `10 at. the;,`bottom of the slots. A portion of the strip of metal is then cut olf and the balance 11A is bent inward to secure the disc-shaped insulating member 19 (see Fig. 3). A portion ofthe cylindrical wall of the contactmaking element 15 is expanded to form a shoulder 21 which interlits with one side of the disc-shaped insulating .spacer member 19. The inner end 22 of the contact making element 15 is expanded against the inner sideof `the `disc-shaped insulating member 19 to denitely position the contact making element in coaxial space relationship with the contact `making shield 10. Force litting Within the bore '23 of the contact making element 15 is a cylindrical metal insert 24 having a pointed shaft Zion its inner end (see Fig. 3).

When a mechanic wishes to applythe plug unit P to a shielded or coaxial cable, generally designatedas L,

he lirst `strips about one inch of the sheath 30 from the cable L exposing the stranded shielding coaxial lead 31,

then cuts 01T about one-half inch of the stranded shield coaxial lead 31, exposing the tubular insulation 32 over the central lead 33. The mechanic then forces the tubular insulation 32 together with the central lead 33 onto the pointedshaft` 25, so that the pointed shaft 25 enters thebore* of the tubular insulation 32 and makes positive contact `,with `the central lead 33.

14-ibyway-of'the securing screw 35 to provide mechanical securing of the shielded or coaxial cable to the plug unit and electrical connection of the stranded shielding coaxial lead 31 to the plug unit P.

In Figs. 4 and 5 is illustrated a modified form of securing for the stranded shielded coaxial cable lead L. In this embodiment, upwardly extending fingers 34A cut and formed from the metal of the handle unit H1 (see Fig. 4), are spaced and positioned so that they can be bent around the stranded coaxial lead of the cable L (see Fig. 5), to provide mechanical securing of the shielded or coaxial cable to the plug unit and electrical connection of the stranded shielding coaxial lead 3i) to the plug unit P1.

The receptacle or female unit R (see Fig. 2), is comprised of a cylindrical shielding element 36 within which is iixedly positioned a disc-shaped insulating member 37 having a central hole 38 in which is xedly positioned a.

n i A relief or securing .clampI 341s then `fixedly attached to the handle member tact 'element 39 is arranged to receive and make contact'- with the contact making element 15 of the plug unit P. Wire connections (not shown) to electronic devices -(not shown) within the chassis are soldered Vto 'theY inner end of the female contact element 39. The cylindrical shield element 36 is iixedly mounted on the Vmetal panel- -41lof the chassis, generally designatedC. 'v j f From the above description and the illustrations, itwilll be readily observed that secure and positive connection can be made to a shielded or coaxial cable with little effort on the part of the mechanic making the application. In Figs. 6 and 7 is illustrated a modiiied embodiment 'of our improved connector. In -this embodimentfthe coaxial relationship of the conducting parts is maintained throughout the plug unit P1 and receptacle unit R. In' the latter embodiment, the contacting shield 10A, `slots 11B, shouldered cylindrical portion l22A, contact making element 15A, disc-shaped insulating spacer member 19A, and cylindrical metal insert 24A, with pointed shaft 25A are arranged in the same manner as corresponding parts of the first described embodiment. However, in thelatter embodiment, the contacting shield 10A is lixedly secured l 4 shielded or coaxial cable L, he rst strips about one and one-half inches of sheath 30 from the cable'L, Aexposing by crimping to a cylindrical tapered body member-43 *A hole 44, extending longitudinally through the centerof 1the cylindrical tapered body member, yprovides definite eo{ axial space relationship between the pointed shaft 25A, which extends longitudinally through the hole `44, and the metallic wall of the cylindrical tapered body member 43.

A reduced diameter hole 4S, adjacent to the tapered end 46 of the cylindrical tapered body member 43, is of a size that neatly interts with the external vsurface of the tubular insulation 32 of the shielded or coaxial cable. With 'this' arrangement, it can readily be observed that when th'e 'v" lead 33. The tapered end 46 of the cylindrical tapered i' body member 43 is arranged to intert with an-internal taper 47 in the handle member H1. When the plugl unit P1 is assembled, the stranded shielding coaxial lead 310i cable L is arranged to be positioned between the tapered end 46 of the body portion 43 and the internal taper 47 in the handle H1 (see Fig. 7). lntertting helical'threads on the body portion 43 and handle unit H1 at 48 provide for definite securing of the body portion 43 and handle H1 and clamping action between the tapered end 46 of the tapered body portion 43 and the internal taper 47 in the handle unit H2 to provide denite electrical connection for the coaxial lead 31 and mechanical securing for 'the cable L. A constriction 49 in the lateral hole in thehandle unit H2 is of a size that neatly interlits withthe external surface of the coaxial lead 31 and a hole '50, tapered at its inner end 51 and of a size to neatly interit with the sheath of the cable L, is provided in the' handle unit H2. The handle portion H2 of the plug P1 may be fabricated from metal or insulating material.

When a mechanic wishes to apply the plug unit P1 11o-al the stranded shielding coaxial lead 31. He then threads the cable end into the handle unit. The taper 51 in the hole assists the mechanic in this operation until the cut sheath end 52 abuts the tapered end 51 of the hole 50. With the cable in this latter position, the cut end of the cable extends about one-half inch beyond the threadedend of the handle unit H2. The mechanic now flares the stranded coaxial lead 31 slightly, and threads the tubular insulation 32 into the hole 44 on the threaded body member 43, the-central lead 33 making contact with the pointed shaft 25A, and then forms'the strands vof the stranded coaxial lead over the taper 46 of the body portion 43. He now slides the handle unit H2 up and engages the interiitting helical threads 48 on the body portion 43 and handle unit H2 to secure the entire assembly and electrically connect the central lead 33 and coaxial leadl to the plug unit P1.

From the above description and illustrations of the latter embodiment, it can readily be observed that coaxial positioning vof the current carrying parts and leads is maintained throughout the entire plug assembly P1. The strandedfshielding coaxial lead 31, being Iin coaxiallyl spaced relationship to the central lead 33; the cylindrical tapered -body member 43,"being in coaxially spaced relationship with the pointed shaft 25A; and the contacting shield 10A being in coaxially spaced relationship to the contact making element 15A.

v#lh'e receptacle unit employed with the plug unit P1 is the same as that used with the plug unit P and as illus tratedl in Fig. 2 and described above.

`Although our invention has been described in considerable detail, such description is intended asbeing illus-V trative rather than as limiting, as the invention may be variously embodied, and the scope of the invention is -to be determined as claimed.

We claimy as our invention:

A coaxial and shielding cable terminal 'comprising a tubular contacting shield, a disc shaped insulating membe'r held within said tubular contacting shield, a pointed shaft `held by a metallic insert and centrally supported upon said insulated'disc, a handle member secured to the outside of said -contacting shield, a relief clamp detach-` ably secured to said handle and being adapted to grasp the insulation of a cable, said pointed shaft'being adapted to :pierce one end of the cable whereby electrical contact is made by the metal insert.

References Cited in the tile of this patent

Images