US3829821A

US3829821A - Latching system for an electrical connector assembly and a tool for actuating said system

Info

Publication number: US3829821A
Application number: US00293640A
Authority: US
Inventors: R Harwood; P Derr; G Ferdon
Original assignee: AMP Inc
Current assignee: TE Connectivity Corp
Priority date: 1972-09-29
Filing date: 1972-09-29
Publication date: 1974-08-13
Anticipated expiration: 1991-08-13
Also published as: BE805416A; FR2201552A1; JPS4971483A; GB1441960A; BR7307394D0; IT993215B; DE2348040B2; CA984478A; JPS5750028B2; NL7313317A; ES418896A1; AR198535A1; AU6002073A; DE2348040C3; FR2201552B1; DE2348040A1

Abstract

A changeable interconnecting means comprising a plurality of receptacles arranged in a tightly packed stack with their sides against each other. The receptacles contain contact pins arranged in cells. The pins are connected to external conductors by wires extending from the rearward ends of the pins. Interconnections are made by plug members containing sockets which are dimensioned to fit snugly into the cells. The plug members are individually removable by virtue of latching means recessed in their sides which engage complementary latching means in the receptacles.

Description

[ Aug. 13,1974

United States Patent 1191 Derr et a1..

M M 9 //63 99 3 9 2 w wm 3 3" 3 U m m3 ma M m "I n u u m u n m n n U Inn a "M k 1 .lmI 8 e w ce 1 .11 h ak eunbn fu aeu KRPVDK 5600922 666677 999999 111.111 7 00040 Robert George Harwood,

Mechanicsburg, all of Pa. Primary E.\'aminerBobby R. Gay [73] Assignee: AMP Incorporated, Harrisburgh, Pa.

Assistant ExaminerTerrel1 P. Lewis ABSTRACT [22] Filed: Sept. 29, 1972 [21] Appl. No.: 293,640

A changeable interconnecting means com plurality of receptacles arranged in a ti prising a ghtly packed The rece ptapins stack with their sides against each other.

mma i l 7 M 3 1 0000 Wk 29 II W6 6 R m nws oo 1 ,6 .1 m "52 W. 3 m 2 3 m 36 R9 2 1m ml oo m W9 9 U u 1 3 m #5 3 mh ,O Inn m m S 2 1 m3 d s a 1 U.mF 1:1] 2 8 555 1.1.1.

by virtue of hich engage [56] References Cited UNITED STATES PATENTS complementary latching means in the receptacles.

2,295,119 7/1959 Montgomery, 339/74 R x 11 Clam, 7 Drawmg Flgures 3,179,738 4/1965 DeLyon 339/91 R PATENTEnAus 13 m4 mew LATCHING SYSTEM @FOR AN ELECTRICAL CONNECTOR ASSEMBLY AND A TOOL FOR ACTUATING SAID SYSTEM BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention broadly relates toan electrical connector assembly and more particularly is concerned with a latching system which provides individual connections between connector plugs and connector receptacles of the assembly which allows the plugs and receptacles to be positioned respectively in closely packed stacks wherein by only the use of a tool each plug in the closely packed stack of plugs is individually engageable with a receptacle in the closely packed stack of receptacles and is individually disengageable from the receptacle without disturbing adjacently positioned plugs in the same and adjacent receptacles. The present invention is also more particularly concerned with the tool required for the actuation of the latching system which has two generally parallel elongated arms which facilitate gripping of an individual plug during its insertion into, and extraction from, a receptacle simultaneously as the tool arms actuate the latching system.

1. Description Of The Prior Art Transmission networks in the telephone industry include thousands of electrical conductor wires. Typically, these wires are electrically and mechanically terminated at the rear bay of main or intermediate frames installed at central offices of telephone companies. These wires may serve any of a variety of functions such as carrying incoming or outgoing signals, or carrying signals between the main frame and various test equipment installed at the central office.

The primary purpose of the main frame is to provide a central location at which interconnections between these wires can be made as desired on the front bay of the frame. Typically, the wires terminated at the rear bay of the frame are electrically and mechanically attached to contact terminals mounted in the frame, the attachment being made by either the wire-wrap or soldering techniques. These techniques provide a more or less permanent connection in the sense that the wires cannot be readily detached from the terminals. While permanent connections between the terminals and the wires at the rear bay of the frame are ordinarily desirable, such connections between interconnecting wires and the terminals at the front bay of the frame are not desirable since these connections need to be frequently detached to change the interconnections between the wires terminated at the rear bay of the fame.

One type of interconnection system which has been used heretofore involves terminating the ends of the interconnecting wires to jacks which are pluggable into the main or intermediate frames. These jacks are retained in the frame by conventional detents on the contact terminals mounted in the jacks which mate with conventional complementary detents on the contact terminals mounted in the frame when the respective contact terminals on the jack and the frame are mated.

The incorporation of the .detent retention system into the mating contact terminals .of the jack and the frame creates certain problems.

On the one hand, if the detents and contact terminals are designed such that a high extractionforce is required to unmate them to thereby avoid frequent accidental removal of the jacks from the frame, the plating on the contact surfaces at which the electrical connection is made will be subjected to a high degree of wear each time the jack is removed from the frame which will lead to the need for frequent repair or replacement of the contact terminals in the jack and frame. Furthermore, in view of the fact that an operator may be making hundreds of interconnections each day, an extraction force of from five to ten pounds for each jack imposes a heavy burden on the stamina of the averaege operator.

On the other hand, if the detents and contact terminals are designed such that a low extraction force is required to unmate them, the jacks become susceptible to being accidentally removed from the frame merely by the act of spreading apart of the various interconnecting wires in order to find the jack which the operator desires to remove from the frame. Also, jacks utilizing this type of retention system which has a low extraction force encourages removal thereof by pulling on the interconnecting wires which emanate from the jack.

Furthermore, jacks of the aforementioned type when plugged into the frame cannot be positioned in relation to each other in a closely packed stack since some space is required between adjacent ones of the jacks to allow removal of individual jacks either by hand or by a tool which is inserted through an end of the jack to hook it and then pull it from the frame. This extra space neededbetween the jacks is compensated for by the utilization of small diameter or light weight contact terminals in both the jack-s and the frame. However, the use of small diameter or light weight, and inherently less durable, terminals shortens the effective life span of the terminals and thereby hastens the time when re-' pair or replacement of the terminals will be required.

OBJECTS AND SUMMARY OF THE INVENTION The connector assembly incorporating the latching system of the present invention, and the actuation of this system and the insertion and extraction of the connector plugs of the assembly by the use of the specifically designed tool of the present invention, eliminate all of the aforementioned problems and disadvantages of the above described interconnection system used heretofore.

An object of the invention, therfore, is to provide a connectorassembly in which the retention of individual connector plugs within the connector receptacles is achieved by a novel mechanical latching system which is separate from the electrical and mechanical mating connection between the contact terminals respectively of the plug and receptacle whereby larger diameter, heavier weight, contact terminals may be utilized in the plugs and receptacles of the assembly which enhances the integrity .of the connector assembly and significantly lengthens the life span of the terminals used therein.

' Another object of the invention is to provide a latching system which allows the connector plugs and connector receptacles of the connector assembly to be disposed respectively in closely packed stacks wherein mateable contact terminals mounted respectively within the plugs and receptacles which provide interconnections between a multiplicity of electrical conductor wires terminated to the contact terminals of the receptacles on the rearward side of the receptacles facilitate the provision of the multiplicity of conductor wires in a dense arrangement whereby any space available for the installation of the connector assembly which constitutes the frame is maximumly utilized.

A furtherobject of the invention is to provide a positive latching system separate from the contact terminals of the plugs and receptacles which in allowing the plugs and receptacles to be disposed respectively in closely packed stacks necessitates the use of a specifically designed tool to actuate the system and to achieve rapid insertion and extraction of the plugs into and from the receptacles which thereby eliminates accidental removal of the plugs caused by spreading of the interconnecting wires to find the desired plug and discourages pulling on the interconnecting wires to extract the plugs.

These and other objects of the invention are achieved in a preferred embodiment thereof wherein a latching system for providing an individual connection between each of an array of closely stacked connector plugs and each of an array of closely stacked connector receptacles includes first interengaging means disposed at spaced intervals along an interior surface of each of two parallel aligned elongated walls of each receptacle which walls receive a plurality of plugs in a row therebetween, a channel defined in each of two opposite sides of a rearward portion of each plug, an access passageway defined at each of the two opposite sides of the rearward portion by each of the channels therein to gether with respective facing like channels on the rearward portions of adjacent plugs, a flexible latch arm connected to the rearward portion of each plug within at least one of the channels at a position therein short of the front end of the rearward portion, and second interengaging means disposed on the end of the latch arm and aligned with one of the first interengaging means of the receptacle and coupled therewith when the plug is received in the receptable.

Also, in a preferred embodiment of the invention the latching system is actuated by a tool which further is used to grip each of the plugs during insertion and extraction of the plug into and from the receptacle. The depth of the access passages defined at each of the two opposite sides of the rearward portion of each plug accommodates two elongated arms of the tool. Each of the tool arms has an inwardly-directed shoulder on the end thereof which is engageable with each of the flexible latch arms at an actuating position therealong located forwardly of the location-of connection of the latch arm and along the rearward portion of the plug. In the case of the plug having only one latch arm, one of the tool arm shoulders would engage theforward end of abottom wall of the channel simultaneously as the other tool arm shoulder engages the latch arm. Each of the tool arms further has an interior surface portion adjacent to each of the shoulders which is shaped to engage the bottom wall of the channel rearwardly of the location of connection of the latch arm to the channel when the tool arms are moved toward each other. Movement of the tool arms toward each other accordingly moves the tool arm shoulders toward each other which forces the flexible latch arms to pivotally flex toward each other which displaces the second interengaging means of the latch arm from the first interengaging means of the receptacle and simultaneously causes the tool arm interior surface portions to engage the channel bottom walls,.whereby the plug may be readily extracted from the receptable without disturbing the adjacent plugs of the array of closely stacked plugs in the same andadjacent receptacles.

Other objects and attainments of the inventionwill become apparent to those skilled in the art upon a reading of the following detailed description when taken in conjunction with the drawings in which there is shown and described an illustrative embodiment of the invention; it is to be understood, however, that this embodiment is not intended to be exhaustive nor limiting of the invention but is given for purpose of illustration in order that others skilled in the art may fully understand the invention and the principles thereof and the manner of applying it in practical use so that they may modify it in various forms, each as may be best suited to the conditions of a particular use.

BRIEF DESCRIPTION OF THE DRAWINGS In the course of the following detailed description reference will be frequently made to the attached drawings in which:

FIG. 1 is a perspective view of an electrical connector assembly embodying the principles of the present invention having two-contact and four-contact connector plugs disposed in closely packed stacks in the same and adjacent connector receptacles disposed in closely packed stacks and further illustrating two of the twocontact connector plugs and one of the four-contact connector plug disengaged from the connector assembly with a tool gripping the four-contact connector plug and the tool gripping one of the two-contact connector plugs;

FIG. 2 is a top plan view of the connector assembly embodying the principles of the present invention with some two-contact and four-contact connector plugs received in the receptacles of the connector assembly;

FIG. 3 is an enlarged fragmentary sectional view of the connector assembly taken along line 33 of FIG. 2 showing a four-contact connector plug prior to extraction from a connector receptacle by the use of the tool; FIG. 4 is an enlarged fragmentary sectional view of the connector assembly similar to that of FIG. 3 showing the four-contact connector plug during its extraction from the connector receptacle by the use of the tool;

FIG. 5 is an enlarged fragmentary sectional view of the connector assembly taken along line 55 of FIG. 2 showing a two-contact connector plug prior to extraction from a connector receptacle by the use of the tool; FIG. 6 is an exploded, perspective view of the tool shown in fragmentary form in FIGS. 1 and 3 through 5; and

FIG. 7 is a perspective view of the tool of FIG. 6 illustrating the tool in assembled form.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now in greater detail to the various figures of the drawings wherein like reference characters refer to like par-ts, there is shown at 10 in FIGS. 1 and 2 an electrical connector assembly for disengageably interconnecting a multiplicity of electrical conductors 12, the assembly forming the preferred embodiment of the present invention. The assemblylO is comprised by a plurality of connector receptacles 1-4 which in the preferred embodiment of the invention receive a plurality of four-contact connector plugs1l6 and/or a plurality of two-contact connector plugs 18.

Each of the receptacles14 may be molded from a suitable flame-resistant plasticinsulating material such as poly terephthalate resin to form a substantially rigid one-piece structure.

Each of the receptacles 14 is comprised by a rectangular block and a plurality of hood portions 22 arranged in a row on, and integrally formed with, the block 20. Each of the hoodportions 22 is defined by two pairs of oppositely disposed, and interconnected,

walls

24, 26 which extend from the block 20. Each wall 24 of the one pair of walls is integrally connected with a like wall 24 of the corresponding one pair of walls of adjacent hood portions 22. At least one wall 26 of the other pair of walls of the hood portions 22 forms a common partition wall between adjacent ones of the hood portions 22.

In the preferred embodiment of the invention, a plurality of longitudinal cavities 27 are defined through the block 20 of each receptacle, the cavities being disposed in spaced apart relation from each other and aligned in two rows. A plurality of contact terminal posts 28 emanate from the cavities at the rearward end of the block 20 of each receptacle 14.

The posts 28 are electrically andmechanically connected to contact terminal pins 30 which are also mounted within the same longitudinal cavities 27 of each block 20. The pins 30, beingmounted in cavities 27 and thus disposed in substantially the same spaced apart relation from each other as the posts .28 and aligned in the same two rows, emanate from the cavities 27 at the forward end of the block 20 of each receptacle 14. The hood portions 22 divide the pins 30 into groups of four with two pins in each of two rows within each hood portion .22.

The contact terminal posts 28 a re ofthe known type and adapted to be electricallyand mechanically connected to the multiplicity of electrical conductors 12, in the preferred embodiment of the invention, by the conventional wire wrap technique as used in the telephone and communicationsindustry. The contact terminal posts 28 and pins 30 heretofore referred to are merely illustrative of the types of terminals used in conjunction with the preferred embodiment of the invention and are not per se a part of the invention. Therefore, for purposes of brevity and clarity in this detailed description of the invention, the electrically and mechanically interconnected posts 28, pins 30 and conductors 12 may be characterized as first conductor means 32.

Each wall 24 of the one pair of walls of each hood portion 22 has a window 34 formed therein which opens onto both an exterior surface 36 and an interior surface 38 of the wall 24. The window 34 ispartially defined by ashoulder 40-(see also FIG. 3) which faces toward the block portion 20 of the receptacle 14. The function and purpose of the shoulder 40 will be described in detail later. The window 34'does not necessarily need to be formed completely through the wall 24. It is so formed for convenience in the molding of the receptacle 14. However, it is readily seen that the shoulder40 could be formed in teh wall 24 such that it only opened onto the interior surface 38 of the. wall Each wall '26 of the other pair of -walls of each hood portion 22 has guide means42 formed on the interior surface44 of the wall 26. Also, polarizing'means46 are formed at one of the four corners of intersection between the

walls

24, 26 of the two pairs of walls defining each hood portion 22.

.The receptacles 14 are disposable together in a closely packed stack as shown in FIG. 1 wherein sach stack the exterior surfaces 36 of the walls '24 of each hood portion 22 and the corresponding sides-48 of the block 20 which are coplanar with the exterior surfaces 36 are positionable against like exterior surfaces 36 and sides 48 of adjacent receptacles 14.

As shown in FIGS. '1 and 2, the connector assembly 10 includes three receptacles 14 with each receptacle having four hood portions 22. However, it is readily apparent that the rectangular'blocks 20 of the assembly 10 could be any desired length so as to have any desired number of hood portions 22 extending therefrom according to the area desired to be encompassed by the connector assembly when the assembly is incorporated into the main orintermediate frames used in the telephone industry. Further, the receptacles 14 could be molded togetherso as to integrally'form a total-onepiece structure rather than molded asthe individual one-piece rectangular receptacles 14 shown in FIGS. 1 and 2.

Each of the connector plugs 16,18 may be .molded from a suitable flame-resistant plastic insulating material such aspolycarbonate resin to fonn a substantially rigid one-piece structure.

The four-contact connector plugs 16 will now be described in detail. The two-contact connector-plug 18 which will be described'later is substantially identical to one-half of the four-contact connector plug 16. Therefore, most of the features of the plug '18 will be readily apparent upon a reading of the following description of the plug '16.

Each oftheplurality of four-contact connector plugs 16 in the assembly 10 is rectangular in cross-section and comprised by a forwardportion 50 and a rearward portion 52. The forward portion 50 of each plug "16 is receivable withineach hood portion 22 of the receptacles l4. lnthe preferred embodiment of the invention, when the forward portion 50 is received within the hood portion 22, two pairs of opposite sides 54, S6 of the forward portion 50 are disposed againstthe

interior surfaces

38, 44 of the two pairs of opposite walls24, 26 of the hood portions 22. Further, when the forward portion is received within the hood portion 22, the rearward portion 52 extends from the hood portion 22. The rear portion 52 has two pairs of opposite sides 58, which correspond to the two pairs of

opposite sides

54, 56 of the forward portion 50.

The cross-sectional thickness of the rearward portion 52 between its opposite sides 58 is greater than the cross-sectional thickness of the forward portion50 between its opposite sides 54 by an amount approximately equal to twice the thickness of the wall 24 of the hood portion 22 with such cross-sectional thickness of the rearward portion 52 between its sides 58 being distributed in relation to that of the forward portion 50 in such a way that each side 58 of the rearward portion 52 is displaced outwardly from the corresponding side-54 of the forward portion 50 through a distance equal to the thickness of the wall 24 of the hood portion 22 whereby each of the sides 58 of the rearward portion 52 is substantially coplanar with the corresponding exterior surface 36 of the walls24-of the hood portions 22.

Furthermore, the cross-sectional thickness of the rearward portion 52 between its opposite sides 60 is also greater than the cross-sectional thickness of the forward portion 50 between its opposite sides 56 by an amount approximately equal to the thickness of the wall 26 of the hood portion 22 with such crosssectional thickness of the rearward portion 52 between its sides 56 being distributed in relation to that of the forward portion 50 in such a way that each side 60 of the rearward portion 52 is displaced outwardly from the corrsponding side 56 of the forward portion 50 through a distance equal to one-half of the thickness of the wall 26 of the hood portion 22 whereby each of the sides 60 of the rearward portion 52 is substantially coplanar with an imaginary plane which extends through the wall 26 of the hood portion 22 so as to bisect the thickness of the wall 26.

It is readily apparent that when the forward portions 50 of adjacent plugs 16 are received in adjacent hood portions 22 of the same receptacle l4 and of adjacent receptacles 14, the rearward portions 52, having the above-described proportioned cross-sectional thicknesses and displaced sides in relation to those of the forward portions 50, will be positioned against each other in a closely packed stack as illustrated in H68. 1 and 2.

In the preferred embodiment of the invention, each plug 16 has four longitudinal cavities 62 defined therethrough, the cavities 62 being disposed in spaced apart relation from each other and aligned two in each of two rows, and further preferably aligned with the cavities (not shown) in the block of the receptacles 14 when the plugs 16 are received in the receptacles 14. In the preferred embodiment, the cavities 62 are substantially circular in cross-section. The largest cross-sectional dimension (the diameter) of each cavity 62 in the rearward portion 52 of each plug 16 and the relative displacement of each of the cavities 62 one from the other governs the cross-sectional dimensions of the rearward portion 52. A plurality of lead wires 64 (FIG. 1) emanate from the cavities .62 at the rear end of the rearward portion 52 of the plug 16. The wires 64 are electrically and mechanically secured to contact terminals (not shown) which are mounted in the cavities 62 which, in turn, are electrically and mechanically connected to terminal sockets (not shown) also mounted in the cavities 62 and open at the front end of the plug 16, the sockets being proportioned to receive, and electrically and mechanically mate with, the pins 30 of the receptacle 14 when the plug 16 is received within the hood portion 22 of the receptacle 14. The lead wires 64 of any one of the plugs l6, 18, the wires being shown in fragmentary form in FIG. 1, may provide the interconnection between any other of the plugs l6, 18 as desired. These wires 64 thus constitute the interconnecting wires which provide electrical communication between desired pairs of wires 12 which are terminated at the rear end of the receptacles 14. The lead wires 64, contact terminals (not shown) and terminal sockets (not shown) heretofore referred to are merely illustrative of the types of electrical contact components used in conjunction with the perferred embodiment of the invention and are not per se a part of the invention. Therefore, for the purposes of brevity and clarity in this detailed description of the invention, these components may be characterized as'second conductor means 66.

Plug 16 further includes guide means 67 disposed on its forward portion 50 on each of the opposite sides 56 of the forward portion 50 which guide means 67 interengage with the guide means 42 on each of'the interior surfaces 44 of the receptacle hood portion walls 26 to assist in the insertion of the plug 16 into the hood portion 22. Also, polarizing means 68 are formed at one of the four corners of intersection between the

sides

54, 56 of the forward portion 50 which polarizing means 68 match the polarizing means 46 of each receptacle hood portion 22 to insure proper orientation of the insertion of the plug 16 into the receptacle hood portion 22.

Turning now also to FIGS. 3, 4, and 5, there is illustrated a latching system 69 incorporated in the receptacles l4 and plugs 16, 18 of the connector assembly 10 of the present invention. The latching system 69 includes a first channel defined in .each of the two opposite sides 58 of the rearward portion 52 of each plug 16. The channel 70 originates at the rear end of the rearward portion 52 and extends to a position of termination 72 located short of the front end of the rearward portion 52 of the plug 16. Each of the first channels 70 extend inwardly from each of the outermost exterior surfaces 74 on each of the two opposite sides 58 of the rearward portion 52 and between adjacent ones of the cavities 62 disposed in the plug 16 adjacent to each of the exterior surfaces 74. Each of the first channels 70 have cross-sectional dimensions which are limited in their magnitude by the displacement of the adjacent cavities 62 one from the other and from each of the respective exterior surfaces 74 such that the positions and dimensions of the channels 70 with respect to the cavities 62 do not interfere with, or disrupt, the desired overall dense arrangement of a multiplicity of the second conductor means 66 within the array of closely packed stack of plugs l6, 18. Accordingly, consistent with the desired overall dense arrangement of the second conductor means 66, thedepth of each of the first channels 70 may at a maximum be substantially equal to the thickness of the wall 24 of the receptacle hood portion 22.

The latching system 69 further includes a second channel 76 defined in each of the two opposite sides 58 of the rearward portion 52 and in each of the two corresponding opposite sides 54 of the forward portion 50 of each plug 16. The channel 76 originates at the location of the termination position 72 of the first channel 70 within the rearward portion 52 and extends into the corresponding side 54 of the forward portion 50. The second channel 76 has a truncated cone shape in crosssection and a relatively greater depth than the first channel 70. Greater structural integrity is required in the rearward portion 52 than in the forward portion 50 since a latch arm 78 is anchored to the rearward portion 52 and the force required to actuate the latch arm 78 and to grip the plug l6 is applied by a tool, as will be described hereinafter, against the rearward portion 52. Therefore, the depth of the second channel 76 may extend partially between the cavities 62 while the depth of the first channel 70 preferably should not.

When the plugs 16 are arranged in their closely packed stack, each of the first and second channels 70,

76 are aligned with, and face, like

channels

70, 76 in each rearward portion 52 of the adjacent plugs 16. However, the hood portion wall 24 is interposed between the portions of thelike second channels 76 in each forward portion 50 of the adjacent plugs 16.

The latching system 69 also includes a flexible latch arm 78 which is connected to the rearward portion 52 of the plug 16 at each of the termination positions 72 of the first channels 70 and extends within each of the second channels 76. The exterior surface 80 of each of the latch arms 78 merges from, and is substantially coplanar with, a bottom wall 82 of each of the first channels 70 and also substantially coplanar respectively with each of the two opposite sides 54 of the forward portion 50 when the latch arms are in their unflexed positions. Each of the latch arms 78 are displaced outwardly from a bottom wall 84 of each of the second channels 76 such that the latch arms 78 may be flexed inwardly toward the second channels 76. Each of the latch arms 78 include a shoulder 86 on the free end thereof which projects outwardly from the exterior surface 80 of each of the latch arms 78 and faces toward the rearward portion 52 of the plug 16. Shoulders 40 which are formed in the walls 24 of each of the receptacle hood portions 22 were referred to earlier. These shoulders 40 are included in the latching system 69. Each of the shoulders 86 is aligned with, and overlies, each of the shoulders 40 formed in the walls 24 of the receptacle hood portion 22 in which the plug 16 is received when each of the latch arms 78 are in their unflexed positions to thereby secure the plug 16 within the receptacle hood portion 22.

Each latch arm 78 is flexibly movable about its location of connection 72 between a latching position, as shown in FIG. 3, wherein the latch arm 78 is unflexed and the shoulder 86 on the latch arm 78 is disposed in a coupling or engaging position in overlapping relation with the shoulder 40 of wall 24 of the receptacle hood portion 22 to thereby prevent extraction of the plug 16 from the receptacle l4, and an unlatching position, as shown in FIG. 4, wherein the latch arm 78 is flexed inwardly toward the second channel 76 and the shoulder 86 on the latch arm 78 is displaced from its coupling or engaging position in relation to the shoulder 40 of the wall 24 of the receptacle hood portion 72 inwardly from the location of connection 72 to thereby allow extraction of the plug 16 from the receptacle 14. The latch arm 78 is normally biased to assume its substantially unflexed or latching position. The latch arm 78 also includes a camming surface 87 on the tip of the free end thereof which slopes outwardly and rearwardly from the tip. The camming surface 87 is engageable against the top portion of the wall 24 aligned with, and displaced above, the shoulder 40 of the receptacle hood portion wall 24 and causes the latch arm 78 to flex inwardly toward the'second channel 76 when the plug 16 is inserted into the receptacles 14 by hand.

The first channel 70 and the latch arm exterior surface 80 on each of the opposite sides 58 of the rearward portion 52 of the plug 16 together with a like first channel 70 and a like latch arm. exterior surface 80 on adjacent plugs 16 define an access passageway 88 on each of the opposite sides 58 of the rearward portion 52 of the plug 16.

There is also shown in fragmentary form in FIGS. 1 and 3 through 5, and in unassembled and assembled forms respectively in FIGS. 6 and 7, a tool 90 of the plier type having two elongated handles 91 which are pivotally hinged together adjacent one of their respective ends at

openings

93 or 94 depending upon whether the tool is to be used in conjunction with plugs 16 or plugs 18. Each of the tool handles 91 at their aforementioned respective one ends has an elongated arm 92 extending therefrom beyond the hinged location of the handles 91, the arms 92 being generally parallel to each other. Each of the tool handles 91 with the arm 92 extending therefrom may be fabricated as a onepiece structure by any suitable known process, such as by stamping, from any suitable known material such as steel sheet metal, or the tool handles 91 could be separately made from a suitable known plastic material by any suitable known molding process wherein the handles 91 are molded onto the arms 92 which may be stamped out from steel sheet metal.

Each of the tool arms 92 are movable toward each other when the tool handles 91 are squeezed together. Each of the tool arms 92 has an inwardly-directed shoulder 95 on the free ends thereof which shoulder 95 is engageable with each of the flexible latch arms 78 at an actuating position 96 therealong located forwardly of the location of connection 72 of the latch arm 78 and short of the front end of the rearward portion 52. Each of the tool arms 92 further has an interior surface portion 97 adjacent to each of the shoulders 95 which surface portion 97 is shaped to engage the bottom wall 82 of each of the first channels 70 rearwardly of the location of connection 72 of the latch arm 78 to the first channel 70 when the tool handles 91 are squeezed together.

Each of the tool handles 91 includes at the other of their respective ends a slotted tab 98 which extends outwardly from the handle 91 in a direction transverse to the longitudinal direction of the handle 91, and a support post 100 disposed adjacent to, and generally aligned parallel with, the slotted tab 98.

The slotted tabs 98 have identical oblong slots 102 defined therein, which slots 102 are generally aligned with each other, when the tool is assembled as shown in FIG. 7, in a direction transverse to the longitudinal direction of the handles 91 to receive a nutted pin screw 104 therethrough for coupling the tabs 98 together in a sliding contacting relationship to facilitate pivotal movement of the tool handles 91 toward and away from each other, through a predetermined length of stroke at the aforementioned other respective ends of the handles 91. The maximum and minimum limits of the stroke through which the handles 91 may be moved are partially determined by the distance between the

ends

106, 108 of the slots 102 which ends 106, 108 are disposed respectively remote from, and adjacent to, the handles 91. The maximum limit of the stroke of the handles 91 is reached when the pin screw 104 is in contact with the remote ends 106 of the slots 102. The minimum limit of the stroke of the handles 91 is reached when the pin screw 104 is in contact with the adjacent ends 108 of the slots 102.

When the tool is assembled, the support posts 100 are disposed in sliding contacting relationship with each other and with a spring 110 retained by, and disposed loosely about, the support posts 100. The spring 100 acts as a biasing means on the handles 91 to maintain the handles 91 at the maximum limit of their stroke.

The maximum limit of the stroke of the tool handles 91 is chosen such that when the tool handles 91 are pivotally hinged at openings 93 by a nutted pin screw 112 with the handles 91 disposed at the maximum limit of their stroke, the displacement between the inwardlydirected shoulders 95 of the tool arms 92 is preferably slightly greater than the cross-sectional thickness of the plug 16 between the first channels 70 of the plug 16. Therefore, the tool arms 92 will'be accordingly preset in alignment with the first channels 70 of the plug rearward portion 52 prior to insertion of the tool arms 92 along the first channels 70 which thereby eliminates any need for the tool operator tosqueeze the handles 91 toward each other in order to independently establish the desired alignment between the tool arms 92 and the plug channels 70. The minimum limit of the stroke of the tool handles 91 is chosen such that when the handles 91 are squeezed together to the minimum limit of their stroke, the inwardly-directed shoulders 95 of the tool arms 92 have flexed the latch arms 78 inwardly to their desired flexed positions whereby the plug 16 may be extracted from the receptacle 14. Furthermore, the establishment of a minimum limit for the stroke of the handles 91 serves to prevent movement of the handles 91, and thus of the arms 92, and accordingly flexing of the latch arms 78 beyond the desired flexed position of the latch arms 78 in order to avoid over-flexing of the latch arms 78 which would possibly cause either the tool arms 92 or the latch arms 78 to ultimately structurally fatigue or breakoff. Thus, the establishment of the minimum stroke limit eliminates any need for the tool operator to subjectively guage the squeezing force whichhe applies to the tool handles 91.

The strength of the tool arms 92 must be great enough to insure the structural integrity of the arms 92 during the transmission of the required amount of force therethrough to achieve flexing of the latch arms 78 to their unlatching position and gripping of the plug 16 with sufficient force to overcome the extraction force required to unmate the four second electrical conductors means 66 of the plug 16 from the four first electrical conductor means 32 of the receptacle 14, the force being transmitted from the handles 91 via the tool arms 92 to the plug 16 when the operator squeezes the han dles 91 together from the maximum limit of their stroke as shown in FIG. 3 to the minimum limit as shown in FIG. 4.

The structural integrity of the tool arms 92 is assured when the cross-sectional dimensions of the tool arms 92 are proportioned in relation to the cross-sectional dimensions of each of the first channels 70 such that while the width of each first channel 70 is slightly greater than the width of each tool arm 92, the maximum thickness of each tool arm 92 is greater than the depth of one of the first channels 70 but less than the depth of the access passageway 88 defined between two adjacent plugs by two facing first channels 70 disposed respectively on the adjacent plugs 16. In other words, the depth of each of the first channels 70, which depth is consistent with the desired overall dense arrangement of the multiplicity of second conductor means 66 within the array of closely packed stack of plugs 16, is less than a predetermined clearance dimension required by the tool arms 92 for the insertion of each of the tool arms 92 along the respective opposite sides 58 of the rearward portion 52 of the plug 16. However, each of the access passageways 88 have a depth greater than the clearance dimension required for insertion of each of the tool arms 92.

Any one of the plugs 16 may be extracted from the receptacle hood'portion 22 as follows. First, as shown in FIG. 3, each of the two tool arms 92 are inserted into the respective access passageways 88 defined at the two opposite sides 58 of the rearward portion 52 of the plug 16. When the shoulders 95 of the tool arms 92 are in contact with the latch arms 78 at an actuating position 96 located forwardly of the location of connection 72 and short of the front end of the rearward portion 52, the tool arms 92 are moved inwardly toward the rearward portion 52. This movement of the tool arms 92 forces pivotal movement of the latch arms 78 from their normal latching position to their unlatching position. Then, with the plug 16 so gripped between the interior surface portions 97 and the shoulders 95 the tool arms 92, the plug 16 may be readily extracted from the receptacle 14 without disturbing the most closely adjacent plugs 16 in the array of closely stacked plugs 16. Extraction of the plug 16 from the receptacle 14 causes unmating of the four second electrical conductor means 66 of the plug 16 from the four first electrical conductor means 32 of the receptacle 14. Also, with the plug 16 so griped between the tool arms 92, the plug 16 may be readily inserted into the receptacle 14 without disturbing the most closely adjacent plugs 16 in the array of closely stacked plugs 16.

The two-contact connector plug 18, as stated hereinbefore, is substantially identical to one-half of the fourcontact connector plug 16. That is, the plug 18 is comprised by one-half of the plug 16 when the plug 16 is bisected by an imaginary plane which is parallel to each of the two

opposite sides

54,58 of the forward and

rearward portions

50,52 of the plug 16. Therefore, each of the plugs 18 includes two of the cavities 62, two of the second conductor means 66 mounted in the respective cavities 62 in a row. The two second conductor means 66 are mateable with two adjacent ones of the first conductor means 32 being mounted in one of the two rows within a receptacle hood portion 22. The plug 18 further includes a first side 114 identical to one of the two

opposite sides

54,58 of the forward and

rearward portions

50,52 of the plug 16; therefore the first side 114 has first and second channels 70, 76', a flexible latch arm 78 with a shoulder 86 and an access passageway 88' defined at the first side 114.

The plug 18 additionally includes a second side 116 which corresponds to the aforementioned imaginary bisecting plane and is disposed opposite to the first side 114. The second side 116 of the plug 18 will be disposed against a like second side 116 of another plug 18 when both of the plugs 18 are received adjacent one another in the same receptacle hood portion 22 (see FIG. 2). Each of the plugs 18 additionally further includes a third channel 118 defined in the second side 116, the channel 118 originating at the rear end of the rearward portion 52 of the plug 18 and extending to the front end of the rearward portion 52'. The third channel 118 of one plug 18 together with a facing like third channel 118 on the second side 116 of the adjacent plug 18 defining another access passageway 120 which has substantially the same dimensions as the access passageway 88' at the first side 114.

When the tool 90 is utilized in conjunction with the two-contact plug 18, the tool handles 91 are pivotally hinged at openings 94 by the nutted pin screw 112 instead of at openings 93. With the maximum and minimum limits of the stroke of the ends of the tool handles 91 disposed remote from their hinged location remaining the same when the tool handles 91 are pivotally hinged togetherat openings 94 as when the handles 91 were hinged together at openings 93, the change of the pivotal axis of the handles 91 from openings 93 to openings 94 shortens the displacement between the shoulders 95 of the tool arms 92 ."The position of openings 94 is chosen in relation to openings 93 such that when the handles 91 are disposed at the maximum limit of their stroke, the displacement between the shoulders 95 of the tool arms 92 is preferably slightly greater than the cross-sectional thickness of the plug 18 between the first channel 70' and the third channel 118 of the plug 18. Therefore, the tool arms 92 will be accordingly preset in alignment respectively with the first channel 70' and the third channel 118 of the rearward portion 52' of the plug 18 prior to insertion of the tool arms 92 therealong which thereby eliminates any need for the tool operator to squeeze the handles 91 toward each other in order to independently establish the desired alignment between the tool arms 92 and the

channels

70, 118 of the plug 18. Further, the position of openings 94 is chosen in relation to openings 93 such that when the handles 91 are disposed at the minimum limit of their stroke, the shoulders 95 of the tool arms 92 have flexed the one latch arm 78' inwardly to its desired flexed position whereby the plug 16 may be extracted from the receptacle 14. When the tool handles 91 are disposed at the minimum limit of their stroke, the shoulder 95 of one tool arm 92 engages the latch arm 78' at the actuating position 96' therealong and has moved the latch arm 78' to its flexed (unlatching) position; simultaneously therewith, the interior surface portion 97 of that one tool arm 92 engages the bottom wall 82' of the first channel 70' and the shoulder 95 of the other tool arm 92 engages the forward end of the third channel 118 of the rearward portion 52 of the plug 18 to thereby sufficiently grip the plug 18 for insertion or extraction of the plug 18 into and from the receptacle 14.

Any one of the plugs 18 may be extracted from the receptacle hood portion 22 as follows. First, as shown in FIG. 5, each of the two tool arms 92 are inserted into the respective access passageways 88', 120 defined respectively at the first and second sides 114,116 of the rearward portion 52' of the plug 18. When the shoulders 95 of thetool arms 92 are in contact respectively with the latch arm 78' at the actuating position 96 and the forward end of the third channel 118, the tool arm 92 in contact with the latch arm 78' is moved inwardly toward the rearward portion 52'. This movement of the tool arm 92 forces pivotal movement of the latch arm 78' from its normal latching-position to its unlatching position and engagement of the interior surface portion 97 of the one tool arm 92 with the first channel 70. Then, with the plug 18 so gripped between the tool arms 92, the plug 18 may be readily inserted into, and extracted from, the receptacle 14 without disturbing the most closely adjacent plug, one being'a plug 18 in the same receptacle hood portion 22, and the others being either four-contact plugs 16 or two-contact plugs 18 in adjacent receptacle hoods 22. Extraction of the plug 18 from the receptacle 14 causes unmating of the two second electrical conductor means 66 of the plug 18 from the two first electrical conductor means 32 of the receptacle 14.

As shown in FIGS. 1 and 2, the connector assembly 10 includes two two-contact connector plugs 18 and five four-contact connector plugs 16 received in respective hood portions 22 of the receptacle 14. However, it is readily apparent that the

plugs

16,18 can be arranged in any combination of two-contact and fourcontact plugs as desired. -It is also readily apparent that, without departing from the principles of the invention, some of the walls 26 which form common partition walls between adjacent ones of the hood portions 22 could be omitted and that two or more of the plugs 16 could be molded so as to integrally connect at their

opposite sides

56,60 respectively of their forward and

rearward portions

50,52 to form eight-contact or 12- contact plugs if desired. Also, two or more of the plugs 18 could be molded so as to integrally connect at their opposite sides which correspond to the opposite sides of the plugs 16 to form four-contact or six-contact plugs if desired. In each of the above-described modifled forms of

plugs

16,18 only one set of the latching system 69 would need to be provided on the modified plugs.

However, since the connector assembly 10 forming the preferred embodiment of the invention is particularly adapted for use in the telephone industry, the four-contact plugs 16 and the two-contact plugs 18 are the preferred types of plugs. In the telephone industry, a pair of conductor wires which comprises a loop is required in order to transmit a message in theform of electrical signals, hence, the preference for the twocontact plug is order to provide the interconnections which close the loop. in the case of local telephone service, only one pair of wires is required. However, in the case of long-distance telephone service, two pairs of conductor wires which comprise two loops are required to transmit a message since an amplifier which operates electrically in only one direction must be electrically tied into each of the two loops. Hence, a four-contact plug is preferred in the case of long-distance telephone service in order to provide the interconnections whic close each of the two loops. 1

it is thought that the invention and many of its attendant advantages will be understood from the foregoing description and it will be apparent that various changes may be made in the form, construction and arrangement of the parts and that changes may be made in the form, construction and arrangement of the connector assembly and tool described without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the form hereinbefore described being merely a preferred embodiment thereof.

terminals in said body portion having contact ends extending into said cells,

a plurality of plug members, each of said plug members being dimensioned to fit snugly into one of said cells, each of said plug members having an axially extending groove extending on two opposite sides thereof, and having cantilever latching arms, said grooves being in alignment with said arms,

said sidewalls having openings therein for cooperation with said latching arms whereby,

adjacent plug members have said recesses in alignment to provide an opening for admission of an extrattion tool to remove an individual plug member from one of said receptacles.

2. lnterconnecting means for selectively and changeably connecting a first multiplicity of wires to a second multiplicity of wires, said interconnecting means comprising:

an electrical receptacle means comprising a housing having a mating face and a rearward face, first contact terminals in said housing extending through said housing to, and beyond, said mating face, said first multiplicity of wires being connected to said terminals adjacent to said rearward face, said housing having hood means completely enclosing said mating face and having barrier walls extending across said mating face between opposite sides of said hood means, said barrier walls and said hood means defining a plurality of individual cells,

a plurality of electrical plugs, each of said plugs comprising a housing having a forward end and a rearward end, said forward end of each plug being in one of said cells, second contact terminals in said plugs, said second contact terminals being mated wtih said first contact terminals,

said rearward ends of said plugs having their sides disposed closely against each other, each of said plugs having on two opposite sides thereof a groove extending along its rearward end to its forward ends, the grooves on the sides of adjacent plugs forming an opening between adjacent plugs,

each of said plugs having latch arm means on said two sides on its forward end, said latch arm means being disengageably latched to said barrier walls, whereby,

an extraction tool can be inserted into said openings to disengage said latch arm means of an individual plug thereby to permit extraction of said individual plug from said receptacle.

3. lnterconnecting means as set forth in claim 2, said cells and said plugs being generally rectangular.

4. lnterconnecting means as set forth in claim 3, said barrier walls having openings therein, said latch arm means having hook portions extending into said openmgs.

5. lnterconnecting means for selectively and changeably interconnecting a first plurality of wires and a second plurality of wires, said interconnecting means comprising:

an electrical receptacle means comprising an insulating housing having a mating face and a rearward face, first contact terminals in said housing extending through said housing, to, and beyond, said mating face,

said housing having rectangular hood means surrounding said mating face, said hood means opposed parallel sides, barrier walls extending between each pair of opposite sides at predetermined intervals, said barrierwalls and said hood means defining aplurality of individual rectangular cells, each of said cells surrounding a predetermined number of said first contact terminals a plurality of electrical plugs, each of said plugs comprising a plug housing having a forward end and a rearward end, said forward ends being in said Cells, second contact terminals in said plugs, said second contact terminals being mated with said first contact terminals,

said rearward ends of said plugs extending beyond said cells and having their sides disposed closely against each other, each of said plugs having on two opposite sides thereof a groove extending along its rearward end to its forward end, the grooves of the sides of adjacent plugs forming an opening between adjacent plugs,

each of said plugs having latching means on said two sides, said latching means being proximate to said forward ends, said latching being in engagement with said barriers and serving to latch said plugs in said cells, whereby each of said plugs is individually removable from its respective cell uponinsertion of a latch disengaging tool into the said openings extending inwardly on each side of said plug.

6. lnterconnecting means as set forth in claim 5, said receptacle means comprising a plurality of receptacle modules, each of said modules having a row of said cells, said modules being stacked against each other.

7. lnterconnecting means as set forth in claim 6, said latching means on each of said plugs comprising latch arms, said latch arms being in alignment with said grooves.

8. lnterconnecting means as set forth in claim 7, each of said modules having openings on opposite sides of each cell therein, said latch arms being in engagement with said openings. I

9. lnterconnecting means as set forth in claim 8, said first contact terminals comprising contact pins, said second contact terminals comprising contact sockets.

hood and dividing said enclosure into a plurality of I cells,

a plurality of electrical contact terminals in said housing, first wires connected to said conductors proximate to said rearward face, said terminals having contact portions extending into said cells,

a plurality of electrical plug members, each of said plug members having a mating end and a rearward end, said mating end being of reduced dimensions to fit snugly within one of said cells, each of said plugs having a forwardly facing shoulder between said mating end and said rearward end, said shoulders being against the edges of said hoods and the edges of said barrier walls, and rearward portions of said plugs being tightly against each other,

a plurality of contact receiving cavities extending through said plugs and second electrical contact terminals in said cavities, wires secured to said terminals proximate to said rearward ends, said first terminals extending into said cavities and being mated with said second terminals, each of said plugs having on two opposite sides a groove extending along its rearward end, to its forward end, an integral cantilever latch arm associated with each of said grooves, said latch arms being integral with said plug in said rearward portion and extending towards said forward portions, each of said latch arms having an outer surface which is coplanar with the floor of its respective groove and having a free end which is flexible towards said forward portion, and openings in said hoods in engagement with said latch arms to latch said plugs in said cells whereby, said grooves in adjacent plugs are in opposed aligned relationship and provide a recess for entry of an extraction tool for engagement with said latch arms thereby to permit flexure of said latch arms of an individual plug, disengagement of said latch arms from said openings and extraction of said plug from its cell.

11. An electrical plug adapted for use with an electrical receptacle which is capable of receiving a plurality of identical plugs in a closely packed arrangement, said plug comprising:

a rectangular housing having a rearward end and a forward end, a forwardly facing shoulder between said rearward end and said forward end, said shoulder being adapted to serve as a stop upon mating of said plug with said receptacle,

a groove extending forwardly on each of two opposite sides of said housing, a cantilever latch arm in each of said grooves, each of said latch arms extending towards said forward end of said housing and having outwardly facing surfaces which are coplanar with the floor of said groove, said latch arms having free ends which are adjacent to said forward end of said housing and having means on said free ends for engagement with said receptacle, said latch arms being flexible laterally towards said forward end of housing to permit engagement and disengagement of said free ends of said arms with said receptacle whereby,

adjacent plugs mated with said receptacle in the same orientation will have said grooves opposite to each other to provide passageways extending towards said forward ends of said plugs, said passageways permitting entry of an extraction tool to capable of flexing said latch arms to disengage an individual plug from said re-

Claims

1. Interconnecting means for changeably interconnecting a multiplicity of wires comprising: a plurality of receptacle members, each of said receptacle members comprising a rectangular housing, said housings being arranged in a tightly packed stack with their wide sides against each other, each of said housings comprising a body portion and a hood portion, a plurality of barrier walls extending transversely between said wide sides in said hood portion, said barrier walls dividing said hood portion into a plurality of rectangular cells, contact terminals in said body portion having contact ends extending into said cells, a plurality of plug members, each of said plug members being dimensioned to fit snugly into one of said cells, each of said plug members having an axially extending groove extending on two opposite sides thereof, and having cantilever latching arms, said grooves being in alignment with said arms, said sidewalls having openings therein for cooperation with said latching arms whereby, adjacent plug members have said recesses in alignment to provide an opening for admission of an extrattion tool to remove an individual plug member from one of said receptacles.

2. Interconnecting means for selectively and changeably connecting a first multiplicity of wires to a second multiplicity of wires, said interconnecting means comprising: an electrical receptacle means comprising a housing having a mating face and a rearward face, first contact terminals in said housing extending through said housing to, and beyond, said mating face, said first multiplicity of wires being connected to said terminals adjacent to said rearward face, said housing having hood means completely enclosing said mating face and having barrier walls extending across said mating face between opposite sides of said hood means, said barrier walls and said hood means defining a plurality of individual cells, a plurality of electrical plugs, each of said plugs comprising a housing having a forward end and a rearward end, said forward end of each plug being in one of said cells, second contact terminals in said plugs, said second contact terminals being mated wtih said first contact terminals, said rearward ends of said plugs having their sides disposed closely against each other, each of said plugs having on two opposite sides thereof a groove extending along its rearward end to its forward ends, the grooves on the sides of adjacent plugs forming an opening between adjacent plugs, each of said plugs having latch arm means on said two sides on its forward end, said latch arm means being disengageably latched to said barrier walls, whereby, an extraction tool can be inserted into said openings to disengage said latch arm means of an individual plug thereby to permit extraction of said individual plug from said receptacle.

3. Interconnecting means as set forth in claim 2, said cells and said plugs being generally rectangular.

4. Interconnecting means as set forth in claim 3, said barrier walls having openings thereIn, said latch arm means having hook portions extending into said openings.

5. Interconnecting means for selectively and changeably interconnecting a first plurality of wires and a second plurality of wires, said interconnecting means comprising: an electrical receptacle means comprising an insulating housing having a mating face and a rearward face, first contact terminals in said housing extending through said housing, to, and beyond, said mating face, said housing having rectangular hood means surrounding said mating face, said hood means opposed parallel sides, barrier walls extending between each pair of opposite sides at predetermined intervals, said barrier walls and said hood means defining a plurality of individual rectangular cells, each of said cells surrounding a predetermined number of said first contact terminals a plurality of electrical plugs, each of said plugs comprising a plug housing having a forward end and a rearward end, said forward ends being in said cells, second contact terminals in said plugs, said second contact terminals being mated with said first contact terminals, said rearward ends of said plugs extending beyond said cells and having their sides disposed closely against each other, each of said plugs having on two opposite sides thereof a groove extending along its rearward end to its forward end, the grooves of the sides of adjacent plugs forming an opening between adjacent plugs, each of said plugs having latching means on said two sides, said latching means being proximate to said forward ends, said latching being in engagement with said barriers and serving to latch said plugs in said cells, whereby each of said plugs is individually removable from its respective cell upon insertion of a latch disengaging tool into the said openings extending inwardly on each side of said plug.

6. Interconnecting means as set forth in claim 5, said receptacle means comprising a plurality of receptacle modules, each of said modules having a row of said cells, said modules being stacked against each other.

7. Interconnecting means as set forth in claim 6, said latching means on each of said plugs comprising latch arms, said latch arms being in alignment with said grooves.

8. Interconnecting means as set forth in claim 7, each of said modules having openings on opposite sides of each cell therein, said latch arms being in engagement with said openings.

9. Interconnecting means as set forth in claim 8, said first contact terminals comprising contact pins, said second contact terminals comprising contact sockets.

10. Interconnecting means for selectively and changeably connecting a first multiplicity of wires to a second multiplicity of wires, said interconnecting means comprising: a plurality of receptacle members, each of said receptacle members comprising a rectangular housing having a mating face and a rearward face, each housing having a hood extending from, and surrounding, its mating face, said hood defining an enclosure which surrounds said mating face, and a plurality of barrier walls extending at equally spaced intervals between two opposite sides of said hood and dividing said enclosure into a plurality of cells, a plurality of electrical contact terminals in said housing, first wires connected to said conductors proximate to said rearward face, said terminals having contact portions extending into said cells, a plurality of electrical plug members, each of said plug members having a mating end and a rearward end, said mating end being of reduced dimensions to fit snugly within one of said cells, each of said plugs having a forwardly facing shoulder between said mating end and said rearward end, said shoulders being against the edges of said hoods and the edges of said barrier walls, and rearward portions of said plugs being tightly against each other, a plurality of contact receiving cavities extending through said plugs and second electrical contact terminals in said cavities, wiRes secured to said terminals proximate to said rearward ends, said first terminals extending into said cavities and being mated with said second terminals, each of said plugs having on two opposite sides a groove extending along its rearward end, to its forward end, an integral cantilever latch arm associated with each of said grooves, said latch arms being integral with said plug in said rearward portion and extending towards said forward portions, each of said latch arms having an outer surface which is coplanar with the floor of its respective groove and having a free end which is flexible towards said forward portion, and openings in said hoods in engagement with said latch arms to latch said plugs in said cells whereby, said grooves in adjacent plugs are in opposed aligned relationship and provide a recess for entry of an extraction tool for engagement with said latch arms thereby to permit flexure of said latch arms of an individual plug, disengagement of said latch arms from said openings and extraction of said plug from its cell.

11. An electrical plug adapted for use with an electrical receptacle which is capable of receiving a plurality of identical plugs in a closely packed arrangement, said plug comprising: a rectangular housing having a rearward end and a forward end, a forwardly facing shoulder between said rearward end and said forward end, said shoulder being adapted to serve as a stop upon mating of said plug with said receptacle, a groove extending forwardly on each of two opposite sides of said housing, a cantilever latch arm in each of said grooves, each of said latch arms extending towards said forward end of said housing and having outwardly facing surfaces which are coplanar with the floor of said groove, said latch arms having free ends which are adjacent to said forward end of said housing and having means on said free ends for engagement with said receptacle, said latch arms being flexible laterally towards said forward end of housing to permit engagement and disengagement of said free ends of said arms with said receptacle whereby, adjacent plugs mated with said receptacle in the same orientation will have said grooves opposite to each other to provide passageways extending towards said forward ends of said plugs, said passageways permitting entry of an extraction tool to capable of flexing said latch arms to disengage an individual plug from said receptacle.