US 3725845 A
A multicontact connector intended primarily for geophysical surveying work is made totally hermaphroditic so that the entire connector can function either as a male or as a female member whereby the connector can be connected to its identical counterpart. Also disclosed is a connector insert from which hollow posts extend to individually enclose half of the contacts anchored in the insert, the posts being distributed in a pattern such that, when two such inserts are face to face and properly indexed, their respective arrays of posts clear one another.
Claims available in
Description (OCR text may contain errors)
United States Patent 1191 Moulin 1 1 Apr. 3, 1973 s41 ENVIRONMENT PROOF CONNECTOR 2,606,224 8 195; Modrey 1....339 49 R Inventor: Robert L. Moulin Placemia Calm 3,271,726 9/1966 Pfendler ..339/49 R I  Assignee: Hughes Aircraft Company, Culver FOREIGN PA 0R APPLICATIONS 799,317 8/1958 Great Britain ..339/186 M  Filed: Mar. 30, 1971 v Primary Examiner-Marvin A. Cham ion ] Appl' 1294l0 Assistant ExaminerTerrell P. Lewis Att0rneyW. H. MacAllister and Joseph E. Szabo  U.S.'Cl. ..339/49 R, 339/89 M, 339/184 M  Int. Cl. ..H0lr 13/64, HOlr 25/10 57 ABSTRACT  Field of Search ..339/47-49, 75,
339/89 R 89 M, 94 R, 94 M, 103 R 103 M i A multlcontact connector intended primarily for 176 M, 184 R, 184 M 186 R, 186 M 184 geophysical surveying work is made totally her- 186 maphroditic so that the entire connector can function either as a male or as a female member whereby the 5 References Cited connector can be connected to its identical counter- I part. Also disclosed is a connector insert from which UNITED STATES PATENTS hollow posts extend to individually enclose half of the 3,070,769 12/1962 contacts anchored in the insert, the posts being dis- 3,112,975 12/1963 tributed in a pattern such that, when two such inserts 2,962,688 11/1960 are face to face and properly indexed, their respective 3,129,993. 4/1964 arrays of posts clear one another. 3,564,709 2/1971 v v 4/1959 Archer et a1. ..339/89 M X 3 Claims, 10 Drawing Figures PATENTEUAPR3 I975 3,725,845
SHEET 10F 5 Norbert L. Moulin,
I PATENTEUAPRB I975 725, 45
SHEET 5 BF 5 Fig. IO.
ENVIRONMENT PROOF CONNECTOR ln geophysical mapping of terrain, frequently for oil,
geophones are distributed over the terrain in a pattern, each of them being connected through an individual cable to a central multiconductor cable which may be a mile long and which leads to an instrument truck. Terrain characteristics are determinted by detonating an explosive charge and recording in the truck electrical signals produced by the geophones in response to earth vibrations induced by the explosive.
Due to the extremely difficult terrain, which may be either a marsh subject to inundation or a parched desert, the long central cable cannot usually be laid by mechanical means such as a cable laying truck. Instead, it must be placed in short sections by a team of laborers. Typically each laborer is given a load of 100 pounds, which will include a secton of cable terminating in connectors at its opposite ends. In laying the cable, the first man in the team will take his 100 pound load of cable and connectors off the truck and will string it from the truck in the direction to be surveyed. The next man will take his section of cable, connect it at one of its ends to the end of the just laid first cable section and will then lay the remainder of the second cable section in the same direction as the first cable section. Successive cable sections are similarly connected to the free end of the previously laid cable section until the necessary length of cable has been laid. 7
Usually locally available laborers are recruited for laying the cable and these laborers will in most, instances be totally unskilled and unfamiliar with electrical connectors and with the method of their assembly. For example, they may not know the difference betweena male and a female connector and if they do know the difference, they will be prone to lay two cable sections end to end so that connectors of the same sex, both male or both female, end up next to one another. Therefore, it has been found desirable to eliminate this possible source of error by making the connectors at both ends of the cable sections identical so that it does not matter which end of the cable section is grabbed hold of when an attempt is made to connect it to the previously laid cable secton. Another desirable feature for geophysical connectors is to make them capable of engaging an identical counterpart in either of two positions so as to reverse the circuit connections made through them. Thus having connected the system and made one reading, any one of its pairs of engaged connectors may be reengaged in their second mode of eng'agement, a second charge exploded, and a second set of readings taken, the two sets of readings having the effect of canceling errors. I
After the first explosive charge, or pair of charges,
-has been detonated and readings recorded, the
geophones will be repositioned in a second pattern further along the direction in which mapping is to be carried out. Consequently, additional sections of cable must be carried from the truck and successively connected to the previously laid sections of cable until it has been sufficiently extended to reach the newly positioned geophones. Since the exploration will typically progress in a long substantially straight pattern, there will come a point where the cable cannot be extended any further by adding additional sections. At this point the truck is driven ahead and a portion of the initially laid sections of the cable are disconnected, picked up and carried downstream from the last laid cable sections where they are connected thereto so as to further extend the cable in the direction in which the surveying operation is to progress. Thus, it may be seen that in the process of geophysical exploration, cable sections have to be connected and disconnected several times each day. Due to the large amount of handling to which the connectors are subject, they are susceptable to damage. This is aggravated by the fact that cable sections may be left in the field, as well as on the truck, unconnected to other cable sections for extended periods of time so that, unless means are provided to protect their contacts, they are subject to corrosion, abrasion and other damage.
One approach which has been used to make the cable sections reversible has been to use a pair of connectors at each of its ends, one of them being male and the other female. This clearly accomplishes the intended purpose but at the expense of requiring four connectors for each cable section.
Another approach has been to use identical connectors at opposite ends of the cable section, each connector having its contacts divided into two groups and containing equal numbers of male and female contacts. This approach is believed to have two disadvantages. Firstly, while the female contacts are fully recessed in the connector and are therefore relatively well protected, the male contacts are exposed pins which are, at best, protected only by a single wall which surrounds them. Thus, they are protected only collectively rather than individually and may therefore be damaged, particularly bent, by a hard object being carelessly pulled across them. Another disadvantage of the last type of connector is that, because they are identical, no way has been found to so engage them to one another as to seal out the elements without the provision of some external means such as short length of hose pulled over a pair of such connectors after they have been engaged. Yet another disadvantage inherent in the type of connector just described is that there is only one position in which they are capable of engaging one another. In other words, all of the male connectors in one such connector must be aligned with all of the female connectors in the other such connector. As mentioned previously, there is a demand for a connector which can be engaged with its identical counterpart in either one of two positions so as to permit connectionsto be reversed thus allowing certain errors which might have been made during one reading to be cancelled during the next reading.
Accordingly, it is a principal object of the present invention to provide a truly hermaphroditic connector which canbe securely engaged with its identical counterpart, preferably in either one of two positions without any external fastening devices.
It is a related object of the invention to-provide an insert which will support and protect all of a set of con tacts in such a manner that they will all engage an identically supported array of contacts in another such insert. 7
Yet another object of the invention is to provide an improved cover for protecting such a connector from damage when'it is not engaged to another connector, and further to protect the cover itself from damage when it is not being used.
second coupling means secured to the connector shell and movable thereon between a first position and a second position so that the secondcoupling means of either of a pair of such connectors in its first position is operative. to engage the first coupling means of the other of such connectors whose second coupling means is in its first position. More specifically, the first coupling means on the connector shell may be a series of threads formed thereon while the second coupling means may be a coupling ring having a matching set of internally running threads formed thereon. Each coupling ring is movable upon its connector shell between a forward position, in which the coupling ring is operative and a retracted position in which the coupling ring is inoperative and the external threads on the connector shell are exposed and operative. Given a pair of .such connectors, they may be secured to one another by placing the coupling ring on one of them in its forward position and the coupling ring on the other, connector in its retracted position, whereupon the two connectors'are secured to one another by threadably engaging the forwardly located coupling ring with the exposed external threads of the connector whose coupling ring is in its retracted-position.
In accordance with another featureof the invention there is provided an insert for anchoring and protecting substantially all of an array of electrical contacts. The insert basically includes a block defining a plurality of openings arranged in an ordered array of columns and rows for anchoring'a corresponding plurality of contacts and a set of hollow posts extending from alternate rows of those openings, each post serving to protect a contact'mounted in and extending from a respective one of the openings in those altemate rows while respective pairs of rows of posts serve to protect the contacts mounted in and extending from the row of openings between them.
In further keeping with this aspect of the invention, the openings and their associated posts are so arranged that when a pair of such inserts are placed face to face and turned substantially 90 relative to one another, the' posts on one of the inserts fit between the posts on the other.
In further keeping with the invention, a dust cover and a protective cap therefor are provided to prevent contamination of the connector contacts when the connector is not connected to another connector. Specifically, the dust cover of the present invention is cylindrical and threaded at one end to be threadable into the coupling ring of the connector when the coupling ring is in its extended position. Additionally, the dust cover is also threaded at its opposite end on which it normally carries a cap threaded thereon. The dust cover and the cap are both attached to the connectorby a chain or similar means to prevent their loss. When the connector is to be engaged to another connector, the dust cover is unscrewed and disengaged therefrom and the dust cover cap is switched from the back end of the dust cover where it normally resides to its front end, to protect the threads which have just been engaged with the coupling ring from contamination. Thus, the next time the connector is disengaged and needsv to be sealed, the dust cover cap is removed from the front end of the dust cover to its back end and the front end of the dust cover may again be screwed into the coupling ring.
Yet another advantageous optional feature of the present invention is the provision of latching means to v facilitate the disengagement of one connector from another. In accordance with this feature of the invention, the latching means is operative selectively to lock the coupling ring in its forward position so that when the coupling ring is being turned to disengage the connector of which it is a part from another connector, the coupling ring will exert an axial force tending I to separate the two. connectors.
The invention will be described in greater detail with reference to the drawings in which FIG. 1 is a cross section through a connector incor porating features of the invention and through its associated dust cap and dust cap cover.
FIG. 2 illustrates a pair of connectors of the type shown in FIG.- 1 engaged to one another, with the coupling" ring of one of them in its retracted position and the coupling ring of thefothe r connector in its forward,'or operative, position.
FIG. 3 is an exploded perspective view of the connector illustrated in FIG. 1.
FIG. 4 is a partially cutaway side view of an alternative embodiment of the connector shown in FIG. 1.
FIG. 5 is a perspective view of an insert suitable for use in the connectors of FIG. 1 and FIG. 4 and having a plurality of hollow posts which rise around half of the contacts anchored in the insert in such a manner as to protect substantially all of them.
FIG. 6 is a side view of the insert illustrated in FIG. 5.
FIG. 7 is a partial cross section along lines 77 of FIG. 5, illustrating the manner in which individual contacts are anchored in the insert.
FIG. 8 is an enlarged bottom view of a portion of the insert shown in FIG. 5, illustrating the configuration of the openings in which its contacts are anchored.
FIG. 9 is a top view of a pair of inserts of the type shown in. FIG. 5, placed side by side but oriented 90 relative to one another, to illustrate the manner in which their hollow posts clear one another when the in-.
' sertsare placed face to face. i
FIG. 10 is an end view of the connector shown in FIG. I to illustrate the arcuate tangs which extend from the end of the connector shell around the insert and its contacts so as to provide, in combination with the corresponding tangs of another connector, a complete protective wall around the contacts when the connectors are engaged to one another.
Referring now to the figures, particularly to FIGS. 1, 2 and 3, an exemplary connector 11 is illustrated in FIG. 1, together with a dust cover 13 and dust cover cap 15 attached thereto. Referring first to the connector II, it is principally comprisedof a cylindrical con nector shell 17 having external threads 24 at its forward end, an array of contacts 20 (see FIG. 7) mounted in an insert 19 at the forward end of the shell 17 and a coupling ring 21 having internal threads 25 at its forward end and mounted upon the connector shell 17 to be axially movable between an extended position, shown in FIG. 1, and a retracted position. In keeping with a principal feature of the invention, the internal and external threads 25 and 24 match one another so that when the coupling ring 21 of a given connector 11 is in its forward position, it is operative to engage the external threads 24 of its identical counterpart connector whose coupling ring 21 is in its retracted position so as to couple the two connectors to one another. The
1 manner in which a connector 11 may be connected to its identical counterpart 11a is illustrated in FIG. 2 where a pair of connectors 11 and 11a are shown at the ends of a pair of cable sections 26. The coupling ring 21 of the first electrical connector 1 l is pushed into its forward position in which its internal threads 25 are exposed and operative to engage the external threads 24 of the other connector 11a. The coupling ring 21a is pushed back into its retracted position in which its internal threads 25 are out of the way and inoperative. Since the connectors 11 and 11a are identical, it does not matter whose coupling ring is used to engage them to one another, so that if desired, in the situation depicted in FIG. 2, the connectors could be equally well engaged by placing the coupling ring 21 in its rearward inoperative position and using the coupling ring 21a to fasten the two connectors to one another. Thus, it may be seen that by the provision of the axially slidable coupling ring 21, the connector 11 is made truly her-- maphroditic, in that it can serve either as a male member (with its coupling ring 25 pushed back) or as a female member (with its coupling ring 21 in its forward position).
As it may be seen from FIGS. 5 and 7, the connector 1 1 contains a large number of contacts 20, so that when a pair of such connectors are engaged in the manner just described, there is a considerable frictional force between their respective sets of contacts, tending to hold them together. To make it easier to uncouple such a connector from its counterpart, it may be provided with a latch 27 anchored in the connector shell 17 immediately behind the coupling ring 21 when the latter is in its forward position. The latch 27, of which there will typically be two, serves to prevent the coupling ring 21 from travelling axially backward on the shell 17 as the ring is being unscrewed from the threads 24 of the connector to which it has been engaged. Consequently, referring to FIG. 2, the connectors there shown may be conveniently disengaged by grabbing the shell portion of the connector 11a and turning the coupling ring 21 of the other connector 11. By virtue of the action of the latch 27, as the coupling ring 21 is being unscrewed, it exerts an axial force against the shell of the connector 11a and is operative to disengage the connectors from one another.
In order to permit the coupling ring 21 to be moved from its forward position to its rearward position, the latch 27 is provided with a spring 29, both of them being retained in a slot 31 in the side of the connector shell 17. As seen in FIG. 3, the slot 31 and the latch 27 are keyed so that once the latch 27 is slipped into the slot it cannot pop out, although it is urged axially outwardly by the spring 29. A latch retaining spacer 33 is slipped into the slot 31 behind the latch 27 to hold it in place therein. The trailing edge of the latch 27 is tapered at 35 so that when the coupling ring 21 is turned from its rearward position to its forward position, it earns the latch 27 inward against the pressure of the spring 29 and rides over the latch into its forward position. The ring 21 is stopped in its forward position on the shell 17 by the cooperative action of a shoulder 10 onthe shell and a rim 14 on the ring.
As a further protective measure for the contacts in the connector, a pair of radially opposed arcuate tangs 35 extend axially forward from the front end of the connector shell 17 (FIGS. 1, 3 and 10). Each of the tangs 35 extends substantially circurnferentially around the insert 19 and the contacts held therein, so that when the electrical connector is engaged with its identical counterpart as in FIG. 2, their tangs 35 together define a substantially continuous protective wall around the contacts. The connector shell 17 is also provided with a pair of diametrically opposed arcuate slots 37 to provide clearance for the arcuate tangs 35 of the other connector to which it is engaged. The tangs 35 also serve a keying function to insure that whenever a given connector 11 is engaged with its identical counterpart connector, their respective shells 17 will be rotated 90 relative to one another. As will become more apparent in connection with the more detailed description of the insert 19, the reason why this is desirable is that the particular insert 19 which is preferred for use in the connector 11 is so arranged that it is engageable with its identical counterpart only when the inserts are turned 90 relative to one another. Naturally, other keying means may also be used to achieve the 90 relationship and, conversely, where a different type of insert is used, and where the protective function of the tangs 35 is not necessary, the tangs may be dispensed with entirely.
An approach often used with connectors intended for a wet environment is to provide a seal between each of the contacts and the, insert in which they are anchored. This approach has the disadvantage of making it difficult to remove the contacts from the insert. A different approach is pioneered in the connector of the present invention. In particular, no attempt is made to provide a seal between the individual contacts of the connector and the insert 19 in which they are anchored. Indeed, as may best be seen in FIG. 7, each of the contacts is anchored in an opening which extends clear through the insert. This has the advantage 4 that any dirt which may accidentally enter the opening will not be captured therein but will fall through it and into the relatively large space 39 which remains inside the connector shell 17. Instead of trying to provide a seal between the contacts and the insert 19, provision is made to insure that moisture will be kept out of the connector both when it is engaged with its identical counterpart and when it is not so engaged. To keep moisture out when the connector is engaged with its counterpart, it is provided with a moisture-sealing ridge 39 at the front end of the connector shell 17 and extending entirely around the insert l9 so that when the connector is engaged with its counterpart, their respective moisture-sealing ridges sealingly abut one another. Preferably the moisture sealingridge 39 includes an O ring seal 41. The back of the connector shell 17 is sealed by means of a cap 43 having a radially extending disk portion 45 and an axially extending front cup portion 47 having a circumferential slot 49 with an O ring seal 51 therein. Thus, when the connector 11 is engaged to its counterpart, it is sealed both at the front and at the back. As a result of the face to face engagement of the rings 41 of the pair of connectors 11, when the coupling ring 21 of one of them is tightened around the shell 17 of the other, a seal can be attained even under 100 ft. of water.
To provide a moisture seal at the front end of the connector 11 when it is not engaged with another connector is the function of the dust cover 13 As illustrated in FIGS. 1 and 3, it is a short cylindrical cup-like member whose front end is made to resemble that of the connector 11. Consequently the dust cover 13 is fastened to the front end of the connector 1 l in exactly the same manner in which another connector would be fastened thereto. More specifically, the front end of the dust cap 13 includes an external thread 53 which matches the internal thread of the coupling ring 21, an O ring seal 54 of the same size as the connector shell forward 0 ring seal 41, and a pair of diametrically opposed .arcuate tangs 55 extend axially, with slots 57 between them so as to receive the arcuate tangs 35 of the connector 11. The dust cover 13 is secured to the connector 11 by a short length of cable 59, whose opposite end is secured to the connector cap 43 by means of a screw 60.
Provision is also made to prevent the dust cover threads 53 from being damaged or soiled when it is not in engagement with its associated connector 11. Toward this end it is provided with a dust cover cap having matching threads 61 and 63 to permit the cap to be screwed onto the back of the dust cover. When the dust cover 13 is not in use, its cap 15 is unscrewed from the back threads 61 and is screwed onto the front threads '53. An 0 ring seal 65, extending around the cap 15, serves to insure that moisture does not reach its front threads 53 nor any of the other portions of the front end of the dust cover 13. The cap 15 is attached to the connector 1 l by means of a cable 67, whose opposite ends are anchored to the cap 15 by means of a screw 69 and to the connector rear cap 43 by means of the screw 60.
As mentioned previously, it is desirable to have the insert 19 of a given connector 11 engage the insert 19 of another such connector with which the fist connector is engaged so that the two inserts are turned 90 degrees relative to one another. Consequently, it is necessary to key the insert 19 so that its orientation within the shell 17 is precisely determined. For this purpose, the connector shell 17 is provided at its front end with a radially inwardly extending ledge 71 having a pair of diametrically opposed slots 73 therein (see FIGS. 1 and 10)]The' insert 19 is provided with a pair of axially extending diametrically opposed keying bosses 75 which fit snugly into the keying slots 73. A pair of circumferentially running ledge portions 77 extend clockwise from each of the keying bosses 75 and serve as stop surfaces to hold the insert 19 injplace against the ledge 71. A pair of arcuate spacers 77 which together define a thin cylinder hold the insert 19 in place within the connector shell 17 and against its ledge 71. Thespacers 71 are in turn held securely in place *against axial movement along the shell 17 by means of the forwardly extending cup portion 47 of the connector rear cap 43. To aid in the assembly of the connector 11, each of the spacers 77 is provided with a keying tang 79 and 81 at its front and back end, respectively. The front keyingtangs 79 fit between the ledge portions 77 of the insert 19 while the rear tangs 81 fit into a pair of diametrically opposed arcuate slots 83 in the front cup portion 47 of the rear cap 43. Thus, the spacers 77 can be used as fingers between which the insert 19 may be grabbed, with the rear ends of the fingers being engaged by the cap 43 so that the spacers 77 and the insert 19 held between them may be pushed into the shell 17 and turned by means of the cap 43 until the insert 19 drops into place at the front end of the shell. When the cap 43 is pushed all the way into the shell 17, its disk portion 45 abuts against the rear end of the shell and closes the slots 31 thereby capturing the latch 27 and the latch retaining spacer 33 therein. The cap 43 is held in place by a set of screws, of which the screw is one, threaded into the wall of the connector shell 17.
In addition to serving to seal the back end of the connector shell 17, and to hold the spacers and the latches 27 in place, the cap 43 also serves the additional important function of securely anchoring the end portion of the cable 26 to the connector. With this regard, it should be realized that the connector 11 is designed to withstand a pull of several thousand pounds against the cable without damage. The coupling of the cable 26 to the cap 43 is achieved in the exemplary connector 11 by means of a strain relief bushing 87, a compression nut 89, and a thrust washer 91 The bushing 87 is long and flexible, and has an internal diameter designed to snugly fit around the cable 26 and has an outwardly flared end 93. The cap 43 has a rearwardly extending internally threaded cup portion which receives the externallyvthreaded. front end of the compression nut 89. When the compression nut-89 is turned into place in the cup 95 of the cap 43, it clamps the flared end 93 of the bushing 87 into the cap 43, and secures the bushing 87, as well as the cable therein, against being pulled out of the connector 11.
An alternative connector incorporating some of the features of the present invention, while eliminating others for the sake of simplicity, is illustrated in FIG. 4. Since the connectors of FIG. 4 and FIG. 1 are quite similar, only their differences will be explained in detail. The basic combination of the connector of FIG. 4 is the same as that of FIG. 1 and includes a connector shell 96, a coupling ring 103 movable between an extended and a retracted position upon the shell 95, and
an insert 97 seated at the front end of the shell 96 and held there by a pair of spacers 99 retained by means of a cap 101. The connector of FIG. 4 differs from the connector 11 in -that the latches 27 have been eliminated. Another simplification is that the two-piece cap 13 and 15 of FIG. 1 has beenreplaced by a onepiece dust cover having external threads 107 adapted to be received in matching internal threads 109' at the front end of the coupling ring 103 when the latter is in its extended position.
Another modification of the connector of FIG. 4 is at its rear end where an improved provision is made for securely attaching a cable to the connector. In particular, the cap 101 has a rearwardly extending cup portion 1 11 similar to the corresponding portion 95 of the connector 11. Seated at the bottom of the cup portion 111 is a rigid cup-shaped compression ring 113 having a radially inwardly sloping cam surface 115. A flexible gland seal 117 is seated next to the compression ring 113 and has a front surface 119 sloped generally parallel to the surface 115 of the ring 113. The flared end 121 of the bushing 123 is compressed between the gland seal 117 and a thrust washer 125 which is pressed against the flared bushing end 121 by a compression nut 127 similar to the compression nut 89 of FIG. 1. As the threaded end of the compression nut 127 is screwed into the matchingly threaded rear end of the cap 101, the front portion of the gland seal 1 17 is pressed against the cam surface 1 of the compression ring 113 and is cammed radially inwardly, thereby becoming squeezed onto the cable which runs through its center. In this way, the cable is grabbed very securely by the gland seal 117 and would require a very great axial force to rip it from the connector.
Referring now to FIGS. 5-10, the insert 19 preferred for use in the exemplary connector, comprises a block 16 defining, or having therein, a plurality of openings 22 arranged in an ordered array of columns and rows 26 and 28 for anchoring a corresponding plurality of contacts 20. In accordance with the invention, a set of hollow posts 23 extends from alternate ones of the columns 26 and from alternate ones of the rows 28 of the openings 22, each post 23 serving as a socket to protect a contact mounted in an extending from a respective one of the openings 22 in the aforesaid alternate columns and alternate rows 26 and 28. Moreover, respective pairs of the columns of posts 26 serve to protect the contacts 20 mounted in and extending from the columns 26 of openings 22 between them and similarly, respective pairs of rows 28 of posts 23 serve to protect the contacts 20 mounted in and extending from the rows of openings 22 between them.
Naturally, if the contacts 20 and the insert 19 did not have to engage a corresponding set of contacts ina similar insert, it would be desirable to have a hollow protective post 22 extend around each one of them. This, of course, is not possible, because if each of the contacts in a given insert were surrounded by a protective post 23, none of them would be accessible by contacts in the insert. It is a particular advantage of the insert of the present invention that a sufficient number of protective posts 23 are provided to effectively protect all of the contacts which are anchored in the insert, yet at the same time permitting all of the contacts to engage ehtir counterparts in another similar, or even identical, insert. How this is achieved is shown in FIG. 9 by illustrating on the left a first insert 190 with its columns 26 of posts 23 oriented vertically, and by showing to its immediate right, an identical insert 191] rotated 90 counterclockwise, so that its columns 26 and posts 23 extend horizontally. A comparison of the connectors 19a and 19b in FIG. 9 will reveal that when they are turned 90 relative to one another as shown in FIG. 9, one of them will have a post 23 at every opening 22 where the other one does not. Stating it differently, the geometrical arrangement of openings and posts is such that when a pair of inserts 19 are turned by 90 relative to one another, their posts complement one another and mesh perfectly when the inserts are placed face to face. If, for example, the inserts 19a and 19b which are shown side by side in FIG. 9 with their faces up, are turned so that their hollow posts 23 extend toward one another, each hollow post on one insert will be in line with a post-less opening in the other. Note for example the posts 23-1 and 23-2 at the left edge of the insert 19a in FIG. 9 which, when the insert 19a is turned over and against the insert 19b, will be against the openings 22-1 and 22-2 of the latter. It will also be observed that the pair of identical inserts 19a and 19b will fit or intermesh not only in the position shown in FIG. 9, but also in a second relative position in which the insert 19b is turned I relative to the position in which it is shown in FIG. 9. The simplest way to appreciate the reason for this is that the insert 19b, as well as the insert 19a of course, is symmetrical about the diameter 30 which extends through the longitudinal axis 32 of the insert 19, about which it is turned into its second engaging position with the insert 19a.
The preferred insert illustrated in FIG. 9 may also be viewed as having its openings 22 distributed in an array of equispaced columns and rows 40 and 42, as shown for the connector 19b in FIG. 9, with the rows and the columns being located in pairs equidistantly about the axis 32 of the insert. With reference to the columns 40 and 42, it will be observed that a hollow post 23 extends from alternate openings in each of the columns and each of the rows in a checkerboard pattern, so that as with a checkerboard, a rotation ofoneinsert relative to the other about its axis 32, causes unlike elements, e.g., an opening with a post versus an opening without a post, to occupy corresponding positions.
Although the particular geometry of the insert 19, illustrated in FIGS. 5-9, is desirable for use in the exemplary connector herein described, where engageability in two different positions of a pair of connectors is desired, the basic feature of the insert 19, whereby hollow protective posts extend from less than all of the openings in the insert to afford effective protection from damage to essentially all of the contacts mounted therein, has broader applicability and may be incorporated into inserts which are differently configured and whose openings 22 are differently laid out than illustrated in FIG. 9. Moreover, although the insert 19 is shown to be removable from the shell 17, it could also be made to be an integral part thereof. Therefore, the word insert as used herein should be understood to include a contact supporting body, whether it is truly a separate insert, as shown herein, or is an integral part of a connector shell;
Turning now to the manner in which contacts may be mounted in the openings 22 of the insert 19, reference should be made to FIGS. 7 and 8, which illustrate the openings 22 as anchoring identical hermaphroditic contacts 20 having a bifurcated blade 32 such that a pair of identical contacts 20 will engage one another when their shanks are in axial alignment but turned about their axes 90 degrees relative to one another, with the bifurcated blades 32 of each contact 20 sliding between the bifurcated contacts of the other. To securely retain the contact 20, the openings 22 are provided with two pairs of diametrically opposed ridges 34, with each pair of ridges forming between them a slot 36, which are so spaced as to receive and snugly engage between them the shank of the contact. A rearwardly extending blade 50 on the contact snaps in place over a ledge 52 in the opening 22 to keep the contact in place therein.
While the primary utility of the exemplary connector disclosed herein is as a hermaphroditic connector, it should be understood that it has sufficient advantages in terms of ruggedness and freedom from damage, both during and between use, as to make it also adaptable to use as a sexed connector in which all of its contacts are either male or female. For example, if such were the case, all of thefemale contacts could be located in those openings from which a hollow post 23 extends, and all of the male contacts, typically pins, would extend from the post-less openings, which would nevertheless be protected by the array of posts rising around them.
In FIG. 10, an insert of the type illustrated in H6. 9, is shown in place, with its axis 32 lying on the longitudinal axis 12 of the connector. As explained previously, the tangs 35 and the slots 37 between them, serve to insure that when the connectors are face to face with their axes colinear, their respective shells will be turned substantially 90 degrees relative to one another about their axes, so that their respective inserts will intermesh. Optionally, a set screw 44 may be located in one of the slots 37 and a slot 46 may be cut in one of the arcuate tangs 35, the set screw 44 and the slot 46 being located 90 apart on the arc of a common circle, centered on the axis of the connector shell 17, so as to permit a pair of connectors to mate in only one of their two possible mating positions. If it is desired that a pair of connectors be permitted to mate in the other of their two possible mating positions, the set screw 44 may be located in a position diametrically across from its position shown in FIG. 10, and to facilitate a changeover, a tapped hole 48 may be provided in the other slot 37 for this purpose. Where a set screw 44 is thus provided, the connector can be quickly converted to engage in either a first position only, or a second position only, or in either of two positions.
A connector substantially as shown in the figures was constructed with a shell diameter of about 2% inches and with a shell length of about v2. inches. It was found that the connector could be made superior to those having metal shells in terms of freedom from binding if the connector were made to have a plastic shell as well as a plastic coupling ring. Indeed, in the connector thus built, the only metal parts were the contacts, the set screw 44, and the fastening screws 60. The connector shell 17, coupling ring 21, latch 27, latch retainer 33, end cap 43, compression nut 89, compression ring 119, were all fabricated from Arylon T, a brand of Polyaryl Ether of Uniroyal Chemical, a Division ofUniroyal, Inc. This type of plastic was chosen because of its high strength and low coefficient of expansion, the latter being particularly important in preventing binding between parts which are threaded into one another and which. are subjected to great variations in ambient temperature.
Noryl GFNZ, a brand of modified phenylene oxide made by the General Electric Company was selected as the material for the insert 19, while the bushing 87 and the gland seal 1 17 were molded from Kraton types 3302 and 3226, respectively both being a brand of styrene-butadiene block copolymer, made by the Shell Chemical Company.
From the foregoing, itmay be seen that a connector having many advantages over those presently existing has been contributed to the art of connectors by the present invention. Thus, a connector has been shown capable of engaging its identical counterpart, in either one of two alternative positions, if desired, yet each connector has been made capable of protecting itself from the environment, both when it is so connected and when it is not. And, by virtue of a novel type of insert, greatly improved protection has been provided for individual contacts which heretofor were subject to damage during periods when the connector was neither coupled to another connector nor otherwise capped.
What is claimed is:
1. An electrical connector engageable with its identical counterpart comprising in combination:
a. a connector shell having a longitudinal axis;
b. a connector insert'mounted at the forward end of said shell and having an axis of symmetry extending across said longitudinal shell axis in a plane normal to said shell axis;
. a plurality of openings in said insert, each extending parallel to said longitudinal shell axis and at least some of them supporting the shanks of contacts therein, said openings being distributed in an array of equispaced columns and rows, said columns being located in pairs equidistantly about said axis of symmetry;
. a hollow post extending integrally from said insert at openings in alternate ones of said columns in a checkerboard pattern symmetrical about said axis of symmetry so that, when a pair of said'connectors are face-to-face, with the axes of their respective connector shells collinear, and the axes of symmetry of their respective inserts turned substantially 90 with respect to each other, their inserts intermesh; and v means for coupling said connector to its identical counterpart with the longitudinal shell axis of said connector being collinear with the corresponding axis of its counterpart and with the axis of symmetry of its insert turned substantially 90 relative to the corresponding axis of the insert of its counterpart about said collinear axes.
2. The electrical connector of claim 1 characterized further in that said connector shell is tubular and said connector insert is disk shaped.
3. The connector of claim 1 characterized further in that said means for coupling said connector to its identical counterpart is operative to interlock said connector to its identical counterpart in either one of two diagonally opposite positions in each of which the axis of symmetry of the insert of said connector is at substantially 90 relative to the corresponding axis of the insert of its counterpart.