US2892991A - Electrical connector - Google Patents

Description

June 30, 1959 F. L. BEEBEE my 2,892,991

ELECTRICAL CONNECTOR Filed Dec. .29, 1955 INVENTORS. FFiDi/(A z. aria: mwm/ a. MIA/05450 United States Patent ELECTRICAL CONNECTOR Frederick L. Beebee, La Canada, and Marvin B. Mendelson, West Los \Angeles, Calif., assignors to The Deutsch Company, a corporation of California Application December 29, 1955, Serial No. 556,220

3 Claims. (Cl. 339--91) The invention relates to electrical connectors of the sectionalized detachable type commonly using axially engageable pin and socket contacts and relates also to this general type of connector which is specially constructed to provide a sealed or environmental-proof chamber for the contacts.

Connectors to which the present invention relates are commonly composed of telescopically arranged sections which carry at their confronting end faces a plurality of pin and socket contacts which are aligned for endwise sliding engagement upon movement of the sections to an attached position and are arranged for disengagement upon reverse movement of the sections to a detached position. The sealed type of electrical connector is required in some installations to protect the integrity of the electrical connections against Weather, moisture, altitude, pressure and temperature changes, etc., all of which may cause the drawing of air and moisture through the unit and result in corrosion or other deterioration of the contacts. The sealed units are sometimes referred to as environmental-proof connectors. Heretofore sealing has been obtained by an end-to-end or face-to-face contact between the two sections and the use of a screw type connection capable of applying sufficient clamping pressure to the confronting end faces to effect a seal. Normal manufacturing and molding tolerances will result in irregularities on these confronting faces which require a relatively great pressure to flatten out and seal. Such screw type clamping means is comparatively slow and awkward to use.

There have also developed in the art similar types of connectors of the quick disconnect type and which use only. lateral locking detents such as ball and sockets, etc. to hold the sections against separation when the sections are moved to attached position. While such detents render the quick detachable connector most convenient to use, they are incapable of applying axial pressure to the confronting end faces, and thus are not used in the sealed type of connector.

It is accordingly an object of the present invention to provide in an electrical connector of the character described a sealing means which functions with but slight pressure readily applied by manually engaging the sections, so as to permit the use of the quick disconnect construction in a sealed environmental-proof connector.

Another object of the present invention is to provide a connector of the character described which will afford a sealed construction without relying upon the end-t0- end' contact of the sections, thus rendering the normal manufacturing and molding tolerances at the confronting faces unimportant, and likewise making the integrity of the seal unaffected by the presence of dirt or foreign matter which normally accumulate on these faces as the sections are connected and disconnected in use.

The quick disconnect type of connector has been favored in aircraft construction so as to minimize the delay and tying up of costly aircraft equipment for instrument repairs and changes. However with-the-advent of 2,892,991 Patented June 30, 1959 transistors and other advances in construction and wiring of the electrical instruments and their components, the instruments have been made smaller and smaller. Accompanying miniaturization, however, of the connectors has been obtained only by the giving up of the quick disconnect features which have heretofore involved rather bulky parts and the going to a more simple threaded or bayonet type of connection. It is accordingly a further object of the present invention to provide an electrical connector of the character described having an improved design and arrangement of the quick disconnect elements which make possible the utilization of this desired construction in an electrical connector of miniature size.

The invention possesses other objects and features of advantage, some of which, with the foregoing, will be set forth in the following descriptions of the preferred form of the invention which is illustrated in the drawings accompanying and forming part of the specification. It is to be understood, however, that variations in the showing made by the said drawings and description may be adopted within the scope of the invention as set forth in the claims.

Referring to said drawings:

Figure 1 is an exploded view partly in elevation and partly in section, of an electrical connector constructed in accordance with the present invention.

Figure 2 is an end view of one of the connector sections as indicated by the plane of line 22 of Figure 1.

Figure 3 is an end view of the other connector section as indicated by the plane of line 3-3 of Figure 1.

Figure 4 is an enlarged fragmentary cross-sectional view of one of the detent means.

Figure 5 is an enlarged fragmentary cross-sectional view similar to Figure 4 but showing the parts in another position.

Figure 6 is an enlarged fragmentary cross-sectional view taken substantially on the plane of line 6-6 of Figure 3.

The electrical connector of the present invention is composed, briefly, of a pair of sections 11 and 12 having telescopically arranged internal and external peripheries 13 and 14 and confronting end walls 16 and 17 defining, in assembled position as seen in Figure 4, an interior chamber 18, electrical contacts 21 and 22 mounted in the chamber 18 for engagement and disengagement upon endwise movement of the sections 11-12 between closed and open positions respectively an annular shoulder 23 provided on one of the peripheries 13-14 (here periphery 14) and preferably formed of yieldable resilient material and dimensioned for sliding sealed engagement with the other periphery so as to seal chamber 18 during the aforementioned movement and in closed position, and manually'operable fastening means 24 for holding the sections in closed position.

Preferably the contacts 21 and 22 are carried by the end walls 16-17 which are here perpendicularly related to the longitudinal axes of the sections and the contacts are thus oriented into axial alignment for engagement upon movement of the sections to closed position. Contacts 21 are here illustrated as a plurality of pins which are molded or otherwise supported in a core piece 26 which is, in turn, molded or otherwise mounted and sealed in an annular outer wall 27 of the section 11. The core 26 may be composed of natural or synthetic rubber or of thermoplastic material providing a firm sealed support for the pins 21. The outer wall 27 is preferably of metal such as aluminum or magnesium in the interests of machinability and lightness in weight, and in the pres ent case provides the smooth interior cylindrical surface 13 which is adapted to receive and seal with the annular shoulder 23. The wall 27 may be provided with an external shoulder 28 and an adjacent clamping nut 29 threaded onto an externally threaded portion 31 of the wall to provide for chassis mounting of the section 11 and leaving a forwardly projecting cylindrical end portion 32 adapted to receive and mate with the other section 12.

Section 12 is similarly composed of an internal solid core 36 of natural or synthetic rubber or thermoplastic material capable of providing a firm, sealed support for the contact sockets 22 and for the core piece itself within an annular outer wall 37 preferably of aluminum or magnesium in the interests of lightness and machinability. The core 36 here provides the inner telescopic section and the external periphery 14 above referred to, and desirably the scaling shoulder 23 is molded integrally with the core. The internal periphery 38 of wall 37 is enlarged so as to surround the core periphery 14 and shoulder 23 in spaced relation defining an annular space 39 dimensioned for receipt of the forward wall portion 32 of section 11.

Preferably and as an important feature of the present invention the shoulder 23 is formed with a convex outer surface desirably semicylindrical in cross-section so as to accomplish its scaling function in the manner of the highly efficient O-ring, thus affording a very good seal with but slight pressure. As will be observed from Fig ures l, 4 and 5, the forward extremity of the internal periphery 13 is divergently tapered as at 41 so as to facilitate the entry of the end 17 and shoulder 23 of the male section. As entry is effected, as observed in Figure 4, the O-rinr shoulder 23 moves into sealed engagement with the internal periphery 13 so as to seal the interior contact chamber 18 and to maintain such seal as the sections are moved to a closed position as seen in Figure 5. As will be further observed, the seal is accomplished with but slight longitudinal pressure easily applied manually in the sliding of the sections together and is obtained without dependence in any way on establishing sealed contact of the end faces 1617. The seal is thus unaffected by normal manufacturing and molding tolerances at such faces or by the presence of dirt or foreign matter thereon which is bound to collect when the sections are disconnected.

The sealing construction as above described, and particularly the absence of required large axial compressive forces, makes possible the adaptation and use in the pres ent connector of quick disconnect latch type holding means for the sections which are capable of holding the sections in closed position against separation but incapable of supplying any appreciable axial compressive force. In the present construction radially displaceable ball detents are used, and the forward portion 42 of wall 37 is provided with a plurality of circumferentially spaced outwardly diverging conical openings 43 which are dimensioned for receipt and support of detent balls 44 and which extend to the interior surface 38 to permit the balls 44 to project interiorly of surface 38 and into engagement with the exterior surface 46 of wall portion 32. The latter surface is here formed with a plurality of recesses or indentations 47 which are positioned in alignment with the balls 44 and dimensioned to receive and interlock with the balls in the closed position of the sections as seen in Figure 5. An external sleeve 48 is mounted on the wall 37 for manual engagement and axial reciprocation between terminal positions as defined by the engagement of an external shoulder 49 on wall 37 with the opposite ends of an elongated annular cham ber 51 provided in the sleeve 48. As will be best seen in Figures 4 and 5, the sleeve 43 is provided with a cam face 52 adjacent its forward extremity and which is arranged to engage the balls 44 upon movement of the sleeve lengthwise in the direction of the open end of section IZF-Which may be denoted for convenience as a first or normal or closed terminal position of the sleeve andwhich is illustrated in dotted lines in Figures 4 and Sleeve 48 is normally spring biased to its normal closed terminal position so as to hold the sections in attached and interlocked relation while at the same time permitting easy and convenient manual engagement and displacement of the sleeve to its reverse or open terminal position which releases the balls for outward movement in their sockets 43 and out of engagement with the indentations 47. As an important feature of the present construction, the spring means for so biasing the sleeve 48 is incorporated in the structure without requiring an enlarging of the structure. As Will be best seen from Fig ure 6, the forward portion 42 of wall 37 and the sleeve 43 are formed to cooperatively define a plurality of circumferentially spaced axially extending elongated spring chambers 53. In the present construction the wall portion 42 is provided with a plurality of circumferentially spaced milled or otherwise formed slots which are radially aligned with milled or otherwise formed slots at the interior of sleeve 48 so as to provide opposed spring retaining chamber walls. Mounted in each of the chambers is an elongated helical spring 54 which is normally compressed between one side of shoulder 49 on wall 37, and an internal shoulder 56 provided at the forward extremity of each of the sleeve slots so that the sleeve will thus be constantly urged by the springs to its first or normal closed position. The springs 54 and balls 44 are preferably formed of stainless steel or the like: to prevent corrosion of the locking mechanism. A shoulder 57 at the rear end of the sleeve 48 moves into engagement with the shoulder 49 to define the maximum extent of forward movement of the sleeve. Shoulder 57 may be spun or pressed over or otherwise formed in the manufacturing of the section after assembly of the internally contained springs 54. The springs mounted in the cooperating slots in the wall 42 and sleeve 48 function also as keys to prevent relative rotation of the sleeve 48 on the section.

To attach the sections, the sleeve 48 is first drawn back against the resistance of springs 54 to its open terminal position as illustrated in Figures 4 and 5, and the tapered end 41 of section 11 is slipped into the annular space 39 of section 12, thus placing the annular shoulder 23 in sealing contact with the internal periphery 13 of section 11 as above explained. At the same time the outside periphery 46 picks up the balls 44 and lifts them outwardly into an annular enlargement 58 provided at the forward end of the sleeve adjacent the cam face 52, thus permitting the cylindrical wall 32 to slide into the annular space 39. In this operation the pins 21 are placed in slid ing axial engagement with the sockets 22 and electrical contact is established. As the sections are moved to closed position, as seen in Figure 5, the balls 44 move into registration with the indentations 47 thus permitting an inward displacement of the balls into an interlocking position with the indentations by cam face 52 as the sleeve 48 moves endwise to its closed position under the urge of springs 54. In this position the interior surface of the sleeve rides over and covers the outer periphery of the balls and thereby locks them in the indentations 47. To open the sections the sleeve 48 is manually d'isplaced to its open position which permits the balls to be ejected from the indentations 47 upon manual withdrawal of the sections. A color band 50 may be provided on the outside wall 37 of section 12 so as to afford instantaneous visual inspection to determine that the sleeve 48 is in closed locked position. If the sections are not pressed home, the sleeve 48 will be held in an open position as indicated in Figure 4, wherein the sleeve will cover and conceal the band 50, thus indicating faulty connection.

Miniaturizing of the unit is assisted by the use of relatively small indentations 47 which consist merely in rather small dimples placed in the periphery 46 of wall 32. The use of a few circumferentially spaced dimples in the wall periphery enables the use of a thin wall section while maintaining adequate strength. The dimples also interlock with the balls to hold the sections against relative rotation and thus reinforce other elements against rotative shearing action when the sections are in connected position, thereby similarly permitting the miniaturizing of other portions of the connector.

To insure proper rotative alignment between the sections and thus proper engagement of the electrical contacts 21 and 22, wall 42 is formed with an axially extending keyway 61 which is adapted to receive a key 62 formed on the wall 32. In the present construction four ball detents are used and are spaced equally about the circumference of section 12 at positions 63, 64, 65 and 66 as seen in Figure 3. Similarly, four spring chambers 53 and springs 54 are provided so as to afford diametrically opposed and circumferentially balanced spring pressures. The spring chambers are located circumferentially between the ball detents as denoted at positions 68, 69, 70 and 71 on Figure 3. The keyway 61 is located between one of the ball detents and one of the springs and, as here shown in Figure 3, between circumferential positions 64 and 69. In this manner all of the operating elements are assembled on wall 42 without interference to provide a most compact miniaturizable arrangement. The tongue and groove relationship is reversed in the present construction from normal practice so as to obtain a contiguous and uninterrupted inside peripheral surface 13 for sealing purposes as above discussed.

As will be observed from Figure 1, the electrical contacts 21-22 are extended completely through their respective core members 26 and 36 and project therefrom into end chambers defined by overhanging extremities 73 and 74 of the walls 27 and 37, where the contacts may be formed as solder lugs, as here shown, to facilitate the connection of electrical conductors 75 thereto. If desired these chambers may also be sealed. This may be accomplished by filling the chambers with potting compound, or, as a feature of the present invention, they may be sealed by compressible sealing grommets or plug members 76 and 77, as here provided. The grommets are formed with a plurality of openings 78 and 79 arranged to slip over the conductors and the solder lugs and are made of soft, compressible material such as natural or synthetic rubber for squeezing down upon the conductors and lugs as by means of clamp nuts 81 and 82 threaded into internally threaded portions on the wall portions 73 and 74. The grommets also act as wire combs and insulators for Wires and provide mutual support for the wires in bundle form;

As another feature of the present construction, generally cylindrical collars 83 and 84, preferably of smooth thermoplastic material such as nylon, are inserted between the grommets 76 and 77 and the clamp nuts 81 and 82 so as to permit ready turning of the nuts to compress the grommets without stretching, distorting or applying peripheral twisting force to the grommets, which in turn might convey such force and strain to the wire connections. The grommets are formed with smooth frustoconical external walls as best seen in the case of grommet 77 and are inserted into the end chambers with their larger end innermost. The collars are formed with reduced outer end portions 86 and 87, which are arranged to grip and displace the frusto-conical exterior walls of the plug members upon axial displacement of the collars into the chambers. Such axial displacement is effected by the provision of internal shoulders 88 and 89 on the clamp nuts 81 and 82 and which engage external shoulders provided on the collars 83 and 84.

As a further feature of the present invention, the openings or bores 79 in the plug members 76 and 77 are each formed with an internal annular O-ring type shoulder 91, which is dimensioned to slidably embrace one of the wires 75 upon assembly and which functions upon compression of the plug member to flow longitudinally of the wire and in sealed engagement there- 6 with as seen in the case of plug memlber76 at the left hand side of Figure 1. Where all of the bores 78--79 of the plug members are not filled with wires, they may be filled with a pin or the like so that a sealed construction results.

We claim:

1. An electrical connector comprising, inner and outer telescopically engageable sections movable axially between open and closed positions and defining an internal chamber, electrical contacts mounted in said chamber for engagement and disengagement upon movement of said sections to closed and open positions respectively, means sealing said chamber during said movement and in said closed position, a wall mounted on and surrounding said inner section in spaced relation and dimensioned to receive said outer section, said wall being formed with a plurality of circumferentially spaced openings, a plurality of balls mounted in said openings for projection interiorly of said wall, said outer section being formed with a plurality of recesses positioned in align ment with said balls and dimensioned to receive and interlock with said balls in said closed position, an external sleeve mounted on said wall for manual engagement and axial reciprocation and being engageable with said balls upon movement in one direction to displace and hold said balls in their interiorly projected position, said wall and sleeve being formed to provide a plurality of circumferentially spaced axially extending elongated spring chambers spaced circumferentially between said openings, and a plurality of elongated helical springs mounted in said chambers in compression between said wall and sleeve and urging said sleeve in said direction, said sleeve being formed to release said balls for outward movement in said openings upon manual movement of said sleeve in a reverse direction against the resistance of said springs so as to thereby permit disengagement of said outer section and movement of said sections from closed to open position.

2. An electrical connector comprising, a pair of inner and outer cylindrical sections having telescopically arranged exterior and interior peripheries and confronting end walls defining an interior chamber, axially extending pin and socket electrical contacts carried by said end walls for engagement and disengagement upon axial movement of said sections between closed and open positions respectively, said inner section being composed of a core of resiliently compressible material and being formed with an integral annular shoulder on said exterior periphery and having a convex outer surface dimensioned for sliding sealed engagement with said interior periphery so as to seal said chamber during said movement and in said closed position, a cylindrical wall mounted on said inner section in spaced concentric relation to said exterior periphery and having an interior surface dimensioned to receive an external surface of said outer section, said cylindrical wall being formed with a plurality of circumferentially spaced openings extending to said interior surface, a plurality of balls mounted in said openings and dimensioned to project interiorly of said interior surface, said external surface of said outer section being formed with a plurality of recesses positioned in alignment with said balls and dimensioned to receive and interlock with said balls in said closed position, an external sleeve mounted on said cylindrical wall for manual engagement and axial reciprocation between first and second terminal positions, said sleeve being provided with a cam face engageable with said balls upon movement to said first terminal position to displace and hold said balls in their interiorly projected position, said cylindrical wall and sleeve being formed to provide a plurality of axially extending elongated spring chambers spaced circumferentially between said ball openings, a plurality of elongated helical springs mounted in said spring chambers in compression between said cylindrical wall and sleeve and urging said sleeve to said first terminal position, said 0am face being formed to release said balls for outward movement in said openings upon manual movement of said sleeve to said second terminal position against the resistance of said springs so as to thereby permit disengagement of said outer section and movement of said sections to open position, said cylindrical wall being formed with an axially extending key way spaced circumferentially between one of said openings and one of said spring chambers, and a key formed on said external surface between a pair of said recesses and engageable in said key way so as to orient and hold said sections in an aligned position of said balls and recesses during said movements.

3. An electrical connector comprising, inner and outer telescopically engageable sections movable axially be tween open and closed positions, a wall mounted on and surrounding in spaced relation said inner section to define an annular space receiving said outer section, said wall being formed with a plurality of circumferentially spaced openings, a plurality of ball detents mounted in said openings for movement intoposition of inter- References Cited in the file of this patent UNiTED STATES PATENTS 2,037,630 Hudson Apr. 14, 1936 2,311,427 Winkelmeyer Feb. 16, 1943 2,662,219 Hennessey Dec. 8, 1953 2,735,993 Humphrey Feb. 21, 1956 2,758,291 Richards Aug. 7, 1956

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