US3372227A - Electrical connector unit - Google Patents

Description

March 5, 1968 K. c. ALLISON ELECTRICAL CONNECTOR UNIT mk Ahorney Kennerh C Allison March 5, 1968 K. c. ALLISON 3,372,227

ELECTRICAL CONNECTOR UNIT Filed Sept. 2l, 1966 2 Sheets-Sheet i Invenor Kennefh .Allison By Win/7 Attorney United States Patent C) 3,372,227 ELECTRICAL' CONNECTOR UNIT Kenneth C. Allison, 1546 S. Shore Drive, Crystal Lake, Ill. 60h14 Filed Sept. 21, 1966, Ser. No. 581,047 7 Claims. (Cl. 174-87) ABSTRACT OF THE DISCLOSURE yentrance pending such deformation of the sleeve.

This invention relates to a connector for electrically joining the unbared ends of insulated wire conductors and more particularly a connector of the type wherein a sleeve of conductive material having an entrance at one end thereof exposes an interior area in which said unbared ends of wire conductors to be joined are receivable for encasement in side by side relation by insertion of said ends intosaid sleeve via said entrance and said sleeve is subjected to a crushing action to compress said sleeve against said ends within the sleeve so as to force teeth formed in said sleeve through the insulation on. said unbared ends of the wire conductors and into engagement with the conductor core of said ends of the wire conductors.

Since the teeth provided in the sleeve occupied by said ends of the insulated wire conductors allow only limited clearance for entry of the ends into the area within the confines of said sleeve there is a tendency for the insulation on the wire ends to become snagged on the teeth during such entry of the wire ends to said area causing the insulation to become hunched at the entrance to said sleeve and thereby stripping said insulation from the portion of the wire ends within the sleeve as well, as the portion of the wire ends immediately outside the entrance to the sleeve. Such exposure of the conductor core of the wire ends is frequently encountered with insulated wire conductors using spirally wound paper or plastic strips as the insulating medium, and as a consequence the circuit containing said connector is thereby susceptible to shorting.

It is accordingly an object of the present invention to provide an improved connector of the type described above wherein the interior area of the sleeve is of gradually diminishing cross-sectional size away from the entrance to said area. A sleeve which is thus flared outwardly in the direction of the entrance to its interior area allows the wire ends to slide past the teeth of the sleeve without risk of injury to the insulation on the wire ends incident to the installation of the wire ends into side by side relation within the interior area of the sleeve whereby exposure of the conductor core at the entrance to said sleeve is avoided.

It is a further aim of this invention to facilitate the proper entry of the insulated wire ends into the interior area of the sleeve by providing teeth in the sleeve which slant inwardly and ina direction toward which the wire ends are moved incident to movement of the wire ends into a fully installed position within the sleeve, except for teeth which face toward the entrance of the sleeve in opposed relation to the teeth which slant in the direction away from the entrance. Such teeth facing toward the entrance are shorter than the teeth which slant in the direction away from the entrance.

It is also an object of this invention to provide a novel method of controlling the dimension of the assembly so as to hold its transverse cross-sectional size consistent with the transverse cross-sectional size of the assembly at the smallest end of the sleeve throughout the area of the sleeve occupied by the ends of the wire leads.

Other objects and advantages of the present invention will become more apparent during the course of the following description, when taken in connection with the accompanying drawings, wherein:

FIG. l is a view of a connector and a pair of insulated wire leads having nnbared ends thereof within the conlines of said connector as the same appear preparatory to deformation of the connector into compressed relation to said wire lead ends, with portions of the connector broken away.

FIG. 2 is a sectional view taken along line 2 2 of FIG. l. j

FIG. 3 is a similar sectional view showing the con nector when deformed into compressed relation to the wire lead ends contained therein.

FIG. 2a is a sectional view taken along line ZL- a of FIG. 2.

FIG. 5a is a similar sectional Sii- 3a of FIG. 3.

FIG. 4 is an exploded view in perspective of the connector components prior to application of the lconnector to a pair of wire leads to be joined thereby.

FIG. 5 is a fragmentary View of the inner sleeve of the connector forming the subject of this invention showing details of the teeth provided in the inner sleeve as they appear prior to deformation of said inner sleeve.

FIG. 6 is a fragmentary view of the portion of the inner sleeve shown in FIG. 5 as it appears when viewed from a position as revealed in FIG. l.

FIG. 7 illustrates a connector as it appears when deformed into compressed relation to the end portions of a pair of insulated wire leads positioned in side by side relation within said connector in accordance with a modied version of the present invention.

FIG. 8 is a transverse sectional view, on an enlarged scale, taken along line 8 8 of FIG. 7.

FIG. 9 is an exploded view illustrating a connector as it appears while about to be deformed into compressed relation to the wire leads positioned therein in accordance with the modified version of the present invention as shown in FIG. 7.

In the drawings reference numeral I6 designates the conductor core of a pair of electrical wire leads having a covering layer of insulating material 11 of suitable composition in relation to which a connector embodying the features of the present invention is operative to electrically join said conductor cores It).

Reference numeral I2 designates a sleeve as shown in FIG. 4 which is preferably formed by a blank of relatively thin sheet metal folded upon itself to produce a tubular body of gradually reduced ovate cross-sectional shape from end to end thereof whereby the sleeve 12 presents a pair of relatively fiattened wall areas at 0pposite sides of a central plane containing the maximum transverse dimension of the sleeve. An outer sleeve 13 formed of thin sheet metal of approximately four times the thickness of the material of the sleeve 12 is telescopically fitted about the sleeve 12. As shown in FIGS. 1 and 2 the outer sleeve 'I3 closely follows the contour of the sleeve 12. A wall I4 closing one end of the outer sleeve 13 serves as a stop against which the inner sleeve I2 has bearing engagement to fix the operative position of the sleeve 12 within the sleeve 13.

view taken along line Withdrawal of the inner sleeve 12 from its operative position within the confines of the outer sleeve 13 is prevented by a tongue 15 sheared and bent outwardly from 'the flattened wall area of the inner sleeve 12 and a recess 16 formed in either of the walls of the outer sleeve 13 which recess presents an edge portion with which the tongue 15 has engagement so as to define an obstruction blocking movement of the sleeve 12 from its operative position. lt will be understood that by providing a recess 16 in each of the opposite walls of the outer sleeve 13 that the tongue 15 of the sleeve 12 is accepted by either of said recesses according to the turned position of the sleeve 12 about its longitudinal axis.

Openings formed in opposite flattened wall areas of the sleeve 12 fianking the portion of the sleeve containing the tongue 15 each have edge portions defining teeth such as teeth 17 shown in FIG. 5 which slant inwardly and in the direction (see arrow) of the innermost region of the sleeve 12 at the side of the openings nearest the entrance to said interior area of the sleeve 12. Other teeth 17a defined by edge portions of the openings farthest from the entrance are somewhat shorter than the teeth -1'7 whereby the teeth 17 provide a cam like surface effective to guide the wire leads away from engagement with the teeth 17n while said wire leads undergo movement toward their installed position within the sleeve 12.

As shown in FIG. 3 and FIG. 3a, the teeth 17 and 17a are forced through the insulation 11 of the ends of the wire leads 1t) confined within the sleeve 12 so as to engage the conductor cores of said leads when the sleeve is compressed about said leads under pressure applied externally against the flattened wall areas of the outer sleeve 13. An electrically conductive connection is accordingly established between the sleeves 12 and 13 and the conductor cores 11) of said leads via said teeth '17 and 17a. While the teeth 17 and 17YL accordingly penetrate the insulation 11 of the wire leads it should be observed that the gradual reduction of the transverse crosssectional contour of the interior area of the sleeve 12 and the forward and inward slant of the teeth 17 as well as the position of the teeth 17 relative to the teeth 17a allows the wire leads to have sliding contact with the surfaces of the teeth 17 during insertion of said leads there` in without danger of disturbing the insulation on said wire leads during such movement of the wire leads toward their installed position within the interior area of the sleeve 12.

The outer sleeve -13 is tightly encased within a layer 18 of insulation material, such as nylon or other suitable composition which is capable of withstanding the compression force applied to the sleeve 13 and sleeve 12 to force the teeth 1.7 and 17.a through the insulation of the wire leads confined in said sleeve 12 without rupturing said layer 18.

Another embodiment of the present invention, asshown in FIGS. 7 and 8, is similar to the connector shown in FIGS. l to 6 inclusive in that the wire leads 1G are conlined within an inner sleeve 22, and outer sleeve 23 and a layer of insulation 24 (corresponding to the sleeve 12, sleeve 13 and insulation layer 18 of the connector as shown in FIGS. 1 to 6 inclusive). It represents a modification of the connector as shown in FIGS. 1 to 6 in that the teeth 17 and 17a formed on the sleeve 22 are forced to penetrate the insulation on the ends of the wire leads facing said teeth by the application of pressure on said layer of insulating material 24 and simultaneously with such deforming action a crease 25 is formed in said sleeves and said layer of insulating material 24 which is effective to condense or reduce the volume of the connector thereby limiting the dimension of the assembly measured in planes intersecting and perpendicular to the axis of the wire leads confined therein to substantially match the corresponding dimension of the connector and wire assembly at the end of the inner sleeve defining the innermost portion of its wire lead containing area. As more clearly shown in FIG. 8, the 'crease .25 is arranged along a line coincident with a plane flanked by -said ends of the wire leads within the inner sleeve 23. FIG. 9 illustrates a pair of pressure members 26 and 27 of such transverse cross-sectional contour as to produce the crease 25 at opposite sides of the connector as shown in FIG. 8. It will also be observed from FIG. 8 that the creases 25 thus formed in the connector is effective to compress the inner sleeve 23 against the wire leads contained therein circumferentially of a cylinder coaxial with the longitudinal axis of each of the wire leads through an arc in excess of degrees, as well as a corresponding compression of the outer sleeve and the layer of insulation attached to the outer sleeve. Such additional area of engagement between the wire leads and the inner sleeve and between the inner sleeve and the outer sleeve tends to give further restraint to forces which act to allow withdrawal .of the inner sleeve from the outer sleeve.

While preferred embodiments of the invention have been illustrated and described herein, it will be understood that changes in the construction may be made within the scope of the appended claims without departing from the spirit of the invention.l

What is claimed is:

1. A connector for electrically joining unbared end portions of la pair of insulated wire leads of predetermined size, said connector including a sleeve of conductive material having an entrance at one end thereof exposing an interior area in which end portions of wire leads to be joined are receivable for encasement in side by side relation when said end portions of said wire leads are inserted in said sleeve via said entrance, opposite wall portions of said sleeve facing said interior area having inwardly extending teeth defined by edge portions of openings formed in said wall portions which teeth penetrate the insulation of said end portions of the wire leads when said leads occupy said interior area and when said sleeve is deformed into compressed relation to said end portions, the portion of said sleeve iny which the leading portion of said wire leads are receivable being so limited in size as to assure frictional engagement between said leading portion of said wire leadsA and the teeth of the sleeve opposite thereto pending deformation of the sleeve into compressed relation to saidwire leads, and the interior area of said sleeve occupied by the other portions of said wire leads being of such progressively greater size toward said entrance as to afford an easement for inward movement ofthe wire leads into said area of the sleeve whereby the insulation on said wire leads within the confines of said sleeveare maintained intact pending such deformation of the sleeve intol cornpressed relation to said wire leads, `an outer conductive sleeve telescopically fitted about said first sleeve, means securing said outer sleeve against withdrawal from said telescopically fitted position about said first sleeve pending deformation of said sleeve into compressed relation to said end portions of the wire leads when said leads occupy said interior area, andan outer layer of insulation material on the outer surface of said outer sleeve, said insulation material having the qual/ity of transmitting forces therethrough and through said outer sleeve to deform said first sleeve into compressed relation to said end lportions of said wire leads while the latter are within said first sleeve without rupturing said layer of insulation material on said outer sleeve.

2. A connector according to claim 1 wherein means securing said outer sleeve against withdrawal from said telescopically fitted position about said first sleeve include an outwardly extending projection on said first sleeve and a recess in said outer sleeve in which said projection is received.

3. A connector according to Claim 1 wherein the teeth defined by edge portions of openings formed in said wall portions which are nearest to said entrance slant inwardly of the area between said wall portions in a direction away from said entrance.

4. A connector according to claim 1 wherein the teeth defined by edge portions of openings formed in said wall portions which are farthest from said entrance are shorter than the teeth defined by edge portions of said openings which are nearest to said entrance, and said teeth deined by edge portions of said openings which are nearest to said entrance slant inwardly of the area between said wall portions in a direction away from said entrance.

5. A connector, and a pair of insulated wire leads having unbared end portions, said connector including a metal sleeve in which said end portions of said wire leads are conned in side by side relation, an outer metal sleeve telescopically fitted about said iirst sleeve, an outer layer of insulation material applied to the outer surface 0f said outer sleeve, said sleeves and said layer of insulation on the outer sleeve being compressed and defining a crease therein along a line coincident with a plane flanked by said ends of said wire leads with said inner 20 sleeve having compressed engagement with said ends of the wire leads circumferentially of a cylinder coaxial with the axis of each of said wire leads through an arc in excess of 180 degrees, and teeth formed on said inner sleeve penetrating the insulation of said ends of the wire leads to establish an electrical connection between said sleeves and the conductor cores of said wire leads.

6. A connector according to claim 5 wherein said connector has a uniform overall transverse dimension for the full length of the area of the connector occupied by said ends of the wire leads.

7. A connector according to claim 5 wherein the connector is of uniform external dimension measured in a rst plane intersecting and perpendicular to the axis of said wire leads at the innermost portion of the first sleeve and measured in planes parallel to said iirst plane throughout the full length of the area of the connector occupied by said ends of the wire leads, except for said crease.

References Cited UNITED STATES PATENTS 3,064,072 11/1962 Graff et al. 174-87 3,265,807 8/1966 Smith 174-87 3,283,061 11/1966 Bolling 174-87 DARRELL L. CLAY, Primary Examiner.

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