Electrical Cable Connector And Grounding Means

Abstract

An electrical cable connector for attachment with a shielded, conductor cable, the connector having a coupling means, a sizing shell releasably secured to the coupling means, and a housing clamp releasably secured to the sizing shell. A separable ring is seated and confined against a shoulder inside the sizing shell by securing the housing clamp to the sizing shell, the housing clamp also serving to jam an expanded portion of the shielding of the cable between a split ring and a ferrule or ring, internally causing partial or 360.degree. peripheral electrical continuity between the cable shielding and the sizing shell which, in turn, electrically and mechanically, peripherally connects to the external portion of the connector providing overall shielding to the connector contacts. Upon removal of the housing clamp, the split ring may be separated and removed so that the sizing shell may be moved rearwardly from the coupling means to expose the point of connection of the cable conductors to the electrical contact elements. Thus, both the grounding means and the electrical connection means of the connector are exposed for convenient inspection, repair or initial assembly.

Description

BACKGROUND AND GENERAL DISCUSSION

Commonly, a pair of detachable connectors are used to connect groups of electrical conductors at selected locations, as in electrical cables used with ground support equipment for testing aircraft, for example.

An electrical cable of the above type undergoes severe flexing and bending in connection with its storage when attached to and detached from test equipment and aircraft. Hence, breakage is not uncommon. The adapters and connectors of the cables are often multitudinous and quite expensive. To provide the necessary reliability and protection, connectors and adapters have been potted or molded to the cable proper. The means heretofore available for attaching cables to their connectors are bulky, unreliable and do not provide means enabling convenient inspection of the electrical and shielding terminations prior to assembly.

The individual adapters and connectors on such cables are relatively expensive and, as they are frequently potted to the cable, are nonrepairable in that if one wire or one of the adapters or connectors is damaged, which frequently happens, the entire cable assembly becomes unusable. It is advantageous to be able to replace an individual adapter or connector or to be able to make rapid inspection or repair of these cables in the field. It is particularly advantageous to be able to inspect the means used for grounding the cable shielding, particularly in military applications where protection is required against radiofrequency interference, especially radar. Previously known devices have not had convenient means for accomplishing such inspections in connectors having the cable shield internally grounded.

One of the problems with previously known connectors arises because of the difficulty of inspecting the electrical connection of each conductor to its receiving solder cup or pin. In the event of malfunction in one of the electrical components in an associated system, it is advantageous to be able to make rapid connector inspection and repair. In addition, it is advantageous to be able to rapidly inspect the means used for grounding the coupling to the cable shielding, the use of which is especially important in many military applications for protecting against radio frequency interference, especially radar. Previously known devices have not had convenient means for accomplishing such inspections.

Accordingly, I originated a connector for securing a plurality of individual electrical conductors to receiving solder cups or connection pins, the connector having a housing consisting of a coupling means with multiple contact elements on a front portion thereof, a sizing shell that may be axially separated from the coupling means to expose the connection of the electrical conductors with the solder cups or pins, and a housing clamp axially releasable from the sizing shield to expose a separable ring surrounding the cable and being seated against a shoulder at the rear of the sizing shell. A ferrule is confined on the cable to urge a radially expanded portion of the shielding toward the split ring. Preferably, a backup ring is urged by an insulating grommet sleeve against the ferrule, and a multifingered ring is jammed between the expanded portion of the shielding of the cable and the separable ring. As a consequence, the shielding is securely confined to the coupling means in a manner enabling convenient interior inspection of the connector by removal of the housing clamp, division of the split ring, and subsequent axial removal of the sizing shell.

DESCRIPTION OF THE FIGURES OF THE DRAWING

FIG. 1 is a side elevation view, partially in section, illustrating an electrical connector embodying the principles of my invention;

FIG. 2 is an end view of the apparatus shown in FIG. 1;

FIG. 3 is a perspective view of a preferred embodiment of the separable ring used in the apparatus of FIGS. 1 and 2;

FIG. 4 is a perspective view of an alternate embodiment of the separable ring;

FIG. 5 is a fragmentary side elevation view, partially in section, of a modified form of my invention;

FIG. 6 is a perspective view of a preferred embodiment of the multifingered ring used in the connector shown in FIG. 1;

FIGS. 7 and 8 are fragmentary side elevation views, partially in section, of alternate forms of the connector, especially of the ferrule and means for attaching it to the cable shielding.

DESCRIPTION OF PREFERRED EMBODIMENTS

The numeral 11 in the drawing designates the coupling means of an electrical conductor, such means being generally cylindrical and including multiple contact elements 13 (see FIG. 2) extending through a front portion 15 of the coupling means, each contact element adapted to register with a receiving contact element (not shown) of a mating coupling means (not shown). For the purpose of simplifying the location and movements of the a of the connector, the word "front" or "forward" means toward the left of the view shown in FIG. 1 and the words "rear" or "rearward" refer to the right of the view seen in FIG. 1. In addition, the coupling means includes an annular coupling nut 17 having interior threads 19 for securement with the mating coupling means. Preferably, the coupling nut is rotatably confined to the remainder of the coupling means 11 through engagement of a radially extending shoulder 21 with a lip 23 extending radially outward from the front portion 15 of the coupling means.

A rear portion 25 of the coupling means has extending from its rearmost surface one or more connector pins 26, each of which is secured with one of the previously mentioned contact elements 13. Preferably, the connector pins of the solder or crimp type receive the uninsulated ends 27 from a cable having exterior insulation 29, an outer shielding 31 of braided metal fibers, and a plurality of individual electrical conductors having the previously mentioned uninsulated ends 27 extending from individual insulation 33.

An annular sizing shell 35 has an interior portion threaded as indicated by the numeral 37 to register with mating threads on the back and exterior of the coupling means 11. Further, a back portion of the sizing shell is threaded as indicated by the numeral 39 to engage mating threads of an annular housing clamp 41. As a consequence, the annular sizing shell is releasably secured to a back portion of the coupling means 11 to enclose the connector pins 26. And, in addition, the housing clamp 41 is releasably secured to the sizing shell and may be removed rearward therefrom. O-rings 38, 40 may be provided to effect a fluid seal between the coupling means, sizing shell and housing clamp.

A separable ring 42 has an outermost diameter smaller than the interior diameter of the housing clamp 41 and engages a shoulder 43 on a rear portion of the sizing shell 35. Preferably, the separable ring has the form illustrated in FIG. 3 such that it has an outward, radially extending portion 45 connected with an axially extending center 47 and an inward, radially extending portion 49. Also, it has notched portions, as illustrated, such that it may be divided into two or more, but preferably two, portions to enable rearward movement of the sizing shell 35 and internal inspection of the connector as will be explained subsequently.

Extending around the shielding 31 of the cable is a ferrule 50 having an axially extending front portion 51 and a radially extending rear portion 53. The word "ferrule" as used here includes generally ringlike devices. The radially extending portion resides behind an expanded or frayed portion 30 of the end of the shielding 31 as shown in FIG. 1. In addition, a multifingered ring 55 (see especially FIG. 6) has an exterior, smooth portion 54 having a diameter large enough to jam against the rear and inner radially extending portion 49 of the separable ring 42 shown in FIG. 3. The multifinger ring is designed such that it may grip shielding of unequal thickness. The multifingers have little or no airgap radially to prevent the thin shielding wires from extending between the multifingers. Hence the inner portion 49 of the separable ring 42 and the multifingered ring confine the expanded portion of the shielding 31. Improved confinement and restriction of the shielding 31 of the cable is provided through utilization of a multifingered ring 55, especially because of the inwardly extending fingers 56 that engage the enlarged portion of the shielding.

Axial force to confine the expanded portion 30 of the shielding between the ferrule 50 and the separable ring 42 is provided in this instance through utilization of a backing ring 57 that engages a rear portion of the ferrule 50 as shown in FIG. 1. Application of force to the backing ring 57 is provided by an insulating grommet 59 having an exterior portion surrounded by a grommet sleeve 61 confined by an inwardly extending shoulder 63 on the housing clamp 41.

An alternate form of separable ring 65 is illustrated in FIG. 4 in which the ring illustrated is preferably fabricated of a flexible material such as resilient beryllium copper having overlapping ends capable of separation to enable insertion of the ring over the cable and confinement against shoulder 43 of the sizing shell 35 in the same manner as the ring shown in FIG. 3 Such ring 65 has sufficient radial thickness to both seat adjacent shoulder 43 and retainer ring 55 of the FIG. 1 apparatus.

In operation, the grommet sleeve 61, insulating grommet 59, backing ring 57, ferrule 50, multifingered ring 55, and separable ring 42 are inserted over the end of the shielded cable. The uninsulated ends 27 of the electrical conductors of the shielded cable are connected as by soldering, for example, to the connector pins 26 and then the sizing shell 35 is rotated until it is secured by means of the threads 37 to the rear portion of the coupling means 11. After the shielding 31 of the cable has been expanded or frayed, the separable ring 42 of Fig. 3, or 65 of FIG. 4, is inserted against the shoulder 43 of sizing shell 35. The multifingered ring 55 is at that stage already forced in position against the separable ring 42 and engages the expanded or frayed portion 30 of the shielding. The ferrule 50, the backing ring 57, and the insulating grommet 59 are forcibly urged forward upon threading the housing clamp 41 on the threads 39 and the sizing shell 35. As a consequence, the grounding shielding of the cable is securely fastened in an electrically conductive manner to the connector.

To inspect the securement of the shielding to the connector, the housing clamp 41 is rotated until the threads 39 on the sizing shell 35 become separated. Then, the housing clamp may be moved rearward, as may the grommet sleeve 61, the insulating grommet 59, the backing ring 57, and the ferrule 50. To inspect the connections of the uninsulated ends 27 of the electrical conductors with the connector pins 26, the separable ring 42 is divided (it previously having been weakened by the notched portions shown in FIG. 3). Such rings may be divided permanently or may utilize a hinge arrangement rather than having the form shown in FIG. 3. Consequently, the interior of the sizing shell 35, having a diameter larger than the exterior diameter of the multifingered ring 55 or the ferrule 50, is free to move backward, thus exposing the connector pins 26. If flexible separable ring 65 of FIG. 6 is used, its ends are separated until it may be removed by helical movement from the shielded cable to achieve the same result as the separable ring 42 of FIG. 3. Upon completing inspection, the apparatus may be reassembled by threading the sizing shell 35 on the rear of the coupling means 11, placing the ends of the separable ring 42 of FIG. 3 together (or overlapping the ends of the ring 65 of FIG. 4) in position against the shoulder 43 of the sizing shell 35, and by arranging the multifingered ring 55, ferrule 50, backing ring 57, insulating grommet 59, and grommet sleeve 61 in position as previously explained.

An alternate form of my invention is illustrated in FIG. 5, which includes the sizing shell 35 and the housing clamp 41 mutually threaded for engagement at 39. The shoulder 43 of the sizing shell 35 engages a separable ring 71 having in this instance an L configuration as seen in longitudinal section. A ferrule 73 is square as seen in the half-section of FIG. 5, with the expanded or frayed portion 30 of the shielding wrapped essentially 360.degree. around the ferrule. The backing ring 57 is urged against the folded shielding and ferrule 73, with assistance from the insulating grommet 59 and grommet sleeve 61, which is urged forward by the housing clamp 41 when attached to the sizing shell 35. This form of the invention eliminates need for the multifingered ring 55 shown in FIG. 6.

In FIG. 7 is shown an L-shaped ferrule 75 having the expanded or frayed portion 30 of the shielding of the cable folded backward over a horizontally extending leg 77 of the ferrule. Alternatively, the expanded portion 30 of the shielding can be placed without folding over the horizontally extending leg 77 of the ferrule 75 if the leg is oriented as shown in FIG. 8. Thus, the shield may be secured to the ferrule by soldering, welding, crimping, or held with a band 79 as shown in FIG. 7.

While I have shown my invention in only a few of its forms, it should be apparent to those skilled in the art that it is not so limited but is susceptible to various changes and modifications without departing from the spirit thereof.

Claims

I claim:

1. An electrical connector having a separable housing for confining a multiconductor, shielded cable, said connector comprising:

a coupling means including multiple contact elements extending through a front portion and adapted to register with receiving contact elements of a mating coupling means;

a plurality of electrical conductor connector pins secured respectively to said contact elements and extending rearward from the coupling means;

a sizing shell releasably secured to a back portion of the coupling means to enclose the connector pins and having a rearwardly facing shoulder;

a housing clamp releasably secured to the sizing shell;

a separable ring seated against said shoulder in the rear of the sizing shell;

a ferrule adapted to receive said cable;

a multifingered ring jammed against a rear surface of the separable ring by the housing clamp to confine an expanded portion of the shielding of the cable against a front surface of the ferrule.

2. The apparatus defined by claim 1 which further comprises:

a backing ring engaging a rear portion of the ferrule;

an insulating grommet engaging a rear portion of the backing ring and extending rearward and between the housing clamp and the cable.

3. The apparatus defined by claim 1 wherein the separable ring comprises a rigid metal ring having a notched portion to weaken it to enable convenient separability.

4. The apparatus defined by claim 1 wherein the separable ring comprises a flexible metal ring having overlapping ends capable of convenient separation.

5. An electrical connector having a separable housing for confining a multiconductor, shielded cable, said connector comprising:

A coupling means including multiple contact elements extending through a front portion and adapted to register with receiving contact elements of a mating coupling means:

a plurality of electrical conductor connector pins secured respectively to said contact elements and extending rearward from the coupling means:

a sizing shell releasably secured to a back portion of the coupling means to enclose the connector pins and having a rearwardly pacing shoulder;

a housing clamp releasably secured to the sizing shell;

a separable ring radially removable and seated against said shoulder in the rear of the sizing shell;

a ferrule confined on the cable and being connected with the shielding thereof to urge an expanded portion of said shielding into confinement against the rear surface of the separable ring.

6. The apparatus defined by claim 5 which further comprises:

a backing ring engaging a rear portion of the ferrule;

an insulating grommet engaging a rear portion of the backing ring and extending rearward and between the housing clamp and the cable.

7. The apparatus defined by claim 5 wherein the separable ring comprises a rigid metal ring having a notched portion to weaken it to enable convenient separability.

8. The apparatus defined by claim 5 wherein the separable ring comprises a flexible metal ring having overlapping ends capable of convenient separation.

9. For use with an electrical connector having a separable housing for confining a multiconductor, shielded cable, and including a coupling means having multiple contact elements extending through its front portion and connected with a plurality of electrical conductor connector pins extending rearward from the coupling means, the combination of:

a sizing shell releasably secured to a back portion of the coupling means to enclose the connector pins and having a rearwardly facing shoulder;

a housing clamp releasably secured to the sizing shell;

a separable ring seated against said shoulder the the rear of the sizing shell;

a ferrule adapted to receive said cable;

a multifingered ring jammed against a rear surface of the separable ring by the housing clamp to confine an expanded portion of the shielding of the cable against a front surface of the ferrule.

10. The apparatus defined by claim 9 which further comprises:

a backing ring engaging a rear portion of the ferrule;

an insulating grommet engaging a rear portion of the backing ring and extending rearward and between the housing clamp and the cable.

11. For use with an electrical connector having a separable housing for confining a multiconducter, shielded cable, and including a coupling means having multiple contact elements extending through its front portion and connected with a plurality of electrical conductor connector pins extending rearward from the coupling means, the combination of:

a sizing shell releasably secured to a back portion of the coupling means to enclose the connector pins and having a rearwardly facing shoulder;

a housing clamp releasably secured to the sizing shell;

a separable ring radially removable and seated against said shoulder in the rear of the sizing shell;

engaging means for engaging the shielding of said cable for coupling said shielding electrically to the rear surface of said separable ring.

12. The apparatus defined by claim 11 wherein: said engaging means includes a ferrule confined on the cable and being connected with the shielding thereof to urge an expanded portion of said shielding into confinement against the rear surface of the separable ring;

a backing ring engaging a rear portion of the ferrule;

an insulating grommet engaging a rear portion of the backing ring and extending rearward and between the housing clamp and the cable.