IL23630A - Electrical connectors - Google Patents

Description

PATENTS AND DESIGNS ORDINANCE SPECIFICATION Electrical connectors I (we) AMPHEN01 CORPORATION, a corporation of the State of Delaware,, of 2801 South 25th Avenue, Broadview, Illinois U.S.A. do hereby declare the nature of this invention and in what manner the same is to be performed, to be particularly described and ascertained in and by the following statement: — This invention relates to electrical connectors. It is the general aim of the invention to provide an improved electrical connector suitable for atomic missile usage and having all of the. advantages of earlier types relating to resistance to adverse environmental conditions, ruggedness of construction, compactness, and ease of servicing, yet having greatly increased reliability.

It is a specific object of the invention to provide a connector of the general type wherein the individual contacts may be affixed to their conductors prior to assembly in the plug or receptacle of the connector and may thereafter be quickly, easily and conveniently mounted in operating position in the plug or receptacle of the connector and as easily removed therefrom for inspection or replacement, yet with a mechanical arrangement of parts such that any malfunctioning due to misalignment of the contacts is almost entirely eliminated, and by a design wherein so-called "false checkouts" are eliminated.

It may be explained that in some prior types of connectors, particularly when subjected to misuse or abuse, it is possible for the plug and receptacle of the connector to be improperly coupled to each other, yet in a condition that may function intermittently in a manner not always detected by circuit tests but with latent defects that can be catastrophic in actual operation.

Obviously, the accomplishment of the foregoing objects requires the development of a connector having a large number of features that are individually recognized as. being desirable, but and environmental factors that have heretofore been believed to be impossible of simultaneous accomplishment, or at least so antagonistic to each other as to preclude successful combination.

As a solution to this generally recognized dilemma, the present invention proposes utilization of a plug and receptacle wherein both sets of contacts are individually removable by application of properly designed removal tools inserted from the front face of the connector, yet with the plug body being of the so-called "hard front, closed entry" type wherein the plug contacts are housed in hard, rigid dielectric material with openings sized to exclude oversize or misaligned pins, so that the likelihood of misalignment of the connector contacts during engagement of the plug and receptacle is minimized. The present invention further proposes a relationship of parts such that, should any significant misalignment occur, it will infallibly prevent completion of the current path through the connector parts in a manner to be instantly and unquestionably apparent in the pre-flight testing of the missile circuitry.

The present preferred embodiment of the invention specifically designed for the control circuitry of an atomic missile is illustrated in the drawings of this application, . wherein: Figure 1 is a greatly enlarged quarter-sectional view through a multiple contact connector of the pin-and-sleeve type; Figure 2 is a fragmental front elevational view of the front face of the plug body of the connector shown in Figure 1; Figure 3 is a detail perspective of a latch release member utilized in the illustrated connector; Figure 4 is a perspective view of contact removal tool adapted to be utilized with the sleeve contacts used in the plug of the connector; Figure 5 is a greatly enlarged central sectional view of a contact retention clip as used in both the plug and receptacle showing its operating relationship with a latch release tube of the plug; ' Figure 6 is a similarly enlarged detail sectional view of a contact retention clip, taken substantially on the plane of the line 6-6 of Figure 5i Figure 7 is a fragmental sectional view taken through a contact cavity of the plug and showing the mode of operation of the contact latch releasing means therefor; and Figure' 8 is a fragmental sectional view similar to Figure 7 but showing the manner of removal of the sleeve contact from the plug body.

With reference now to Figure 1 particularly, the connector receptacle 10 and plug 11 each have an exterior tubular metal shell 12, 13, having the forward ends arranged to telescope within each other and to provide a peripheral seal for the interior of the connector by an "0" ring 14, carried in the internal groove 15 of the receptacle shell 12. The forward end of the receptacle shell 12 is threaded at 16 to receive a threaded coupling collar 17 having an internal spring ring l8 seated in an internal groove 19 adapted to bear against the flange 20 of the plug shell 13 to removably draw the plug and shell into coupled relation. As shown, the receptacle shell is of the plug shell has a corresponding key or keys 22 to maintain the desired angular relationship between the plug and its receptacle and to thus properly polarize the various individual contacts therein. As illustrated, the receptacle and plug each have a cable support nut 23, 24 threaded to the rearmost end of the shells 12 and 13, with rearwardly extending arms 25 and 26 to support cable clamps (not shown) in the conventional manner.

The plug and receptacle each have a multi-part dielectric insert in which the individual contacts are supported. In the receptacle 10, this insert includes a thin, flat, rigid disc 27, generally referred to as an anti-deflection disc, transversely disposed in the shell 12 and carrying one or more contact retention clips 28 to support the individual pin contacts of the receptacle. The disc 27 is also preferably provided with a resilient sealing member 29 bonded to its forward face and, as shown, has a resilient grommet 30 similarly bonded on its rearward face. The parts 27, 29 and 30 are all locked in the shell 12 by a spring ring 31 and each of these parts have aligned apertures in registry with each of the contact retention clips 28, to provide an elongated longitudinal contact cavity 32 running entirely through the insert at the location of each contact. The rearward ends of each of these cavities, in the area of the resilient grommet- 30, have a plurality of sealing risers 33 formed integrally with the grommet.

In the connector illustrated, the receptacle portion 10 carries the male contacts which, as shown, include a cylindrical sleeve 34 adapted to receive the insulating layer 35 of a flexible conductor 36 which extends into a sleeve portion 37 of the contact wherein it is held by any conventional means, such as crimping.

The contact Illustrated has a positioning shoulder 38 from which a shank portion 39 extends forwardly to a taper 4l terminating in a reversely facing shoulder 42 on the head portion 3 of the contact, which carries the forwardly projecting cylindrical contact pin 44.

The connector plug 11 also Includes a multi-part dielectric insert including an anti-deflection disc 51 held within the connector shell by a locking ring 52, with a resilient sealing grommet 53 bonded to the rear face of the disc and a sealing member 54 similarly bonded on its front face, but in the plug there is also provided a so-called "hard front" body member 55 formed of hard, rigid, smooth-surfaced insulating material. As shown, the body 55 is of generally cylindrical shape, and extends from a generally flat front face 56 to a rearward face 57 which may bear against or be bonded to the sealing member 54. As illustrated the body member 55 has a rearwardly and outwardly extending flange 58 engaging a rearwardly facing shoulder 59 on the inside of the plug shell 13 so that the parts 51, 54 and 58 may be held clamped in pressure relationship by the locking ring 52.

The anti-deflection disc 51 of the plug is also provided with one or more contact retention clips 6l . These clips may be identical to the clips 28 of the receptacle and are best illustrated in Figures 5 and 6, wherein it will be seen that each individual clip 6l consists essentially of a short tubular sleeve 62 having a segmental mounting flange.63 adapted to be molded into the anti-deflection disc 51 or 27 or secured between plural laminations thereof as shown in Figure The sleeve 62 Is longitudinally split, preferably by four or five slots 64 which extend from a point near the mounting flange to the forward end of the sleeve. These slots divide the sleeve into several independently flexible segments 65, each of which is provided with an Inwardly inclined latch tooth 66 to engage a coacting shoulder of a contact, as later described. Each of the segments 65 of the clip has a forwardly extending operating member or trigger 67, preferably having a cam surfaced tip inclined outwardly, as will hereinafter appear.

As best seen in Figure 1 , the several parts of the dielectric insert of the plug are apertured in alignment with each of the contact retention clips 6l to provide elongated contact cavities 71 extending from the wire-sealing risers 72 longitudinally through the parts 53> 51 * 54 and 55 of the insert, except that in the case of the plug, the forward end of each contact cavity 71 has a restricted limiting orifice 73 dimensioned to receive the pin 44 of the male contact, but to encircle it so closely as to preclude insertion of an oversize pin. The orifice 73 is provided, however, with a tapered mouth 74, the angular walls of which act as a guide or funnel to facilitate insertion of the pin contacts into the receptacle. The walls of the mouth portions of each contact cavity also intersect the smooth, flat front face 56 of the body member 55 in a manner to provide peripheral ridges 76 surrounding each of the contact cavities. It will thus be seen that when the connector is coupled, the pressure exerted by the screw-threaded coupling ring 17 will press the body member 55 tightly against the resilient sealing element 29* establishing an overall seal acros the front face of the lu bod w th nd du peripheral sealing ridges around each of the individual j contact cavities. A peripheral seal around the entire contact assembly is also provided by a small forwardly projecting peripheral flange 77 at the outer edge of the face 56 of the body member 55.

Immediately behind the limiting orifice 73 of each contact cavity, the body 55 is provided with a counter-bore 8 to house* the sleeve-type contacts of the plug. These sleeve contacts of the plug are similar to the pin contacts of the receptacle in that they have a rearward sleeve 8l to receive the insulating layer 82 of the individual flexible conductors 83 which extend into and are secured within the sleeve 84 at a point behind the collar 85. The shank 86 and taper 88 of the sleeve contact are also similar to the correspondin parts of the pin contact, to provide a rearwardly facing shoulder 89 similar to the rearwardly facing shoulder 42 and arranged to be engaged by the several latching teeth 66 on the contact retention clip 6l . Thus, the forward cylindrical portion 90 of the sleeve contact may be any one of several types, so long as the forward end thereof is apertured to receive the pin 44.

The counterbores 78 of the plug body are of considerably larger diameter than the forward sleeve portions 90 of the individual contacts used therein, so that each cavity has a longitudinal slideway or channel 91* adapted to loosely receive a tubular release member 92 having a tapered rearward end 93 underlying each of the several trigger portions 67 on the contact retention clip 6l .

The forward end of each release tube 92 normally assumes a position as shown in Figure 1, where it lies immediately behind, but outside of the dimensional limits of the restricted orifice 73 of the contact cavity. The tapered mouth 7 of .each contact cavity is, however, provided with one or more latch release keyways, preferably in the form of radial slots 94 (Figure 2) comprising extensions of the latch release channel 91. In the preferred form of the invention illustrated these keyways are of width sufficiently less than the diameter of the pins 44 and corresponding apertures 73 as to preclude acceptance of an oversize pin, and are sized to extend radially at least beyond the inner diameter of the release tube 92, so that any individual tube may be selectively forced rearwardly by insertion of a properly shaped contact removal tool. A simple form of such a tool is shown in Figure 4, wherein the tool 95 is provided with a multiplicity of fins 97 corresponding in dimensions and orientation to the slots 94. Preferably, however, the tool is also provided with a slideable center pin 96 having an operating collar 98 so that, when the tool is properly inserted in the contact cavity, the fins 97 function to force the sleeve 92 rearwardly until its cam surfaces 93 expand the retention clips and simultaneously release the several latch teeth 66 thereof from the contact shoulder 89. This leaves the entire contact assembly free to move rearwardly, either by pulling on the individual conductors 83 or preferably by operating the collar 98 to force the pin 9 into the sleeve of the contact and push the contact rearwardly, as best shown in Figure 8. κ It is believed obvious that with the form of connector illustrated, the contacts of both the plug and the receptacle may be put in place individually from the rear of each connector insert and may likewise be individually removed, by access to the front of the insert only. In the case of both the plug and the receptacle, mounting of the contacts is easily accomplished simply by inserting the leading end of each contact into a cavity in the rear grommet of the plug or receptacle and sliding the contact forward with an appropriate tool (not shown) until the plural latch teeth of the collet-type contact retention clip snap into position behind the locking shoulder of the contact. In the case of the plug contacts, this action carries the release tube 92 to its forwardmost position due to a light friction drag existing between the sleeve portion 90 of the contact and the release tube. This friction may be created in any convenient way, as by a spring finger 99 pierced from the wall of the tube and biased inwardly to bear against the cylindrical surface of the contact sleeve (Figure 3) .

Removal of any individual contact is equally simple. In the case of the receptacle, it is only necessary to slip a sleeve-like tool (not shown) on the contact pin 44 and slide it back over the head portion 43 of the contact, so that the leading edge of the tubular tool engages the several triggers 67 of the contact retention clip and flexes them outwardly in a manner to release the latch teeth 66 thereof and allow the contact to be drawn rearwardly from the connector insert.

In the case of the connector plug, the restricted pin-limiting apertures 73 and tapered mouth portions 7 of the "hard front" plug body 55 are so formed as to permit easy insertion of properly sized pin contacts 44 and, in fact, to guide the forward tips of such contacts into perfectly mating alignment with the sleeves 90 as the plug is coupled to the receptacle. The apertures 73 are sized to prevent insertion of an oversize pin in the contact sleeves 90, however, as seen in Figure 2, from which it is apparent that the dimensional limits of the apertures (the inner diameter of the arcuate portions forming the orifice 73) corresponds to the maximum diameter of the contact pin, although the radial keyway slots 94 extend beyond these dimensional limits to permit actuation of the sleeve 92 by insertion of a properly keyed latch release tool. Thus, the latch release tool 95 and the latch release tube 92 coact to form latch releasing instrumentalities extending from the forward face 56 of the dielectric insert to the latching means comprising the teeth 66 of the contact retention clips 6l.

The mechanical advantages of the connector outlined above are accomplished in the present invention, however, without sacrifice of electrical excellence, and by an arrangement that provides unusually great reliability in operation. It should first be observed that while the dielectric inserts of both the plug and receptacle consist of several individual parts, these coact in a manner whereby the interfacing surfaces may be permanently bonded to each other so that the resilient grommet and resilient sealing members positioned on the opposite sides of each of the anti-deflection discs 27 and 51 coact to encapsulate the retention clips and latching mechanisms surrounding each individual contact so that all contacts are effectively isolated from each other without air voids permitting the formation of electrical leakage paths.

Upon coupling of the plug and receptacle the contact pins are normally guided in a manner to enter the sleeves of the contacts in accurate alignment, but the arrangement is such that, should one or more of the pin contacts be so deformed as to fail to enter its proper aperture, it cannot possibly establish an intermittent connection. It follows that any defects will invariably be detected during preflight check-out of the circuitry, assuring what has come to be known as "go-no-go" reliability.

It will also be seen (Figure l) that the face portion and tapered mouth apertures of the connector plug are formed so that, as the plug is tightened into the receptacle, concentration of pressure occurring at the peripheral ridges J6 surrounding each of the contact apertures accomplishes an effective vapor seal whereby each contact cavity and its keyways are electrically isolated from all other contacts. Similarly, the marginal flange 77 of the hard front dielectric is embedded into the sealing member 2 to isolate the entire group of contacts from the connector shell.

Having thus described the invention, what I claim as new and desire to protect by Letters Patent is:

Claims (1)

1. CLAIMS In an electrical connector, a dielectric body portion having a front face thereon consisting of hard, rigid insulating material, with at least one contact cavity in said body, with contact latching means in said body spaced rearwardly of the aforesaid front face, and an electrical contact removably latohed within the aforesaid cavity; said front face having a limiting aperture of fixed dimensions substantially smaller than the c vity and in operating alignment with the aforesaid contact} at least one keyway adjacent said limiting aperture but outside of the dimensional limits thereof and with at least one dimension of said keyway being less than the corresponding dimension of the limiting aperture; with a channel in, the body portion extending from the keyway in the aforesaid front face of the dielectric body to the aforesaid latching means, whereby latch releasing means may be extended through a keyway in the front face of the body to release the latching means, and permit removal of the contact from the cavity* 2· In an electrical connector/ a dielectrio body . . . " ■ portion aoeording to Claim i wheroin there is formed a channel in the body portion adjaoent the periphery of the contact sleeve and extending from the keyway in the aforesaid front face of the dielectric body to the aforesaid latching means in the contact cavity thereof, whereby latoh releasing means may be extended through a keywa In the front face of the body to release the latching means and permit withdrawal of the contact from the cavity. 3· In an electrical connector, a dielectric body pin-limiting aperture, 4· In an electrical connector, a dielectric body according to any one of the preceding claims wherein each said cavity has a tapered mouth at the forward end thereof leading to a restricted orifice of fixed dimensions: said cavity also having an enlarged counterbore extending rearwardly from said orifice with at least one narrow radial keyway slot extending outwardly from said restricted orifice and entering said counterbore. 5· In an electrical connector, a dielectric body according to Claim 4, said counterbore in said body containing a sleeve contact therein, with said sleeve contact having a shoulder adapted to be engaged by the aforesaid latching means, and being of substantially smaller diameter than the counterbore to provide a slldeway channel therebetween* 6· In an electrical connector a dielectric body according to any one of the preceding claims in combination with a plug and receptable, each having a tubular metal shell adapted to couple in telescoping relation with the other; said plug and receptable each having a dielectric insert including a relatively thin, rigid disc with at least one retention clip for mounting telescoping pin and sleeve contacts uniting the plug and the receptable; with a yieldable resilient grommet on the rearward face of eaoh of said discs and a yieldable resilient sealing member on the forward face of eaoh of said discs co-acting to encapsulate the retention clips thereon.