US3287687A - Protectors for electrical connectors - Google Patents

Description

Nov. 22, 1966 J. R. MosHER 3,287,687

\ PROTECTORS FOR ELECTRICAL CONNECTORS Filed Aug. 17, 1964 s www United States Patent O 3,287,687 PROTECTORS FOR ELECTRICAL CONNECTORS James R. Mosher, 12613 Saratoga Creek Drive,

' Saratoga, Calif. Filed Aug. 17, 1964, Ser. No. 389,836 1 Claim. (Cl. 339-36) the connector end-facesare exposed to dust and mositure causing the electrically conductive surfaces of the mating elements to suffer impaired conductivity. Moreover, the socket or pin contacts are exposed to mechanical shock during handling often resulting in misalignment of the contacts and improper mating thereafter.

In order to avoid the aforementioned problems the present invention provides a protector for protecting the exposed end-faces of termniated connectors from airborne contamination and rough handling.

It is an object, therefore, of the present invention to provide a means for protecting terminated electrical connectors from dust and moisture.

It is a further object of the present invention to provide a means for protecting terminated electrical connectors from damage due to impact.

These and other objects of the present invention will become more apparent in light of the detailed description as set forth herein below.

For a more complete understanding of the practical application of the present invention, reference is made to the [appended drawings wherein:

FIG. l is a cross-sectional view of typical mating electrical connectors of the axially connecting type;

FIG. 2 is a view, partially in cross-section, of a protective cap of the invention and the socket shown in FIG. l, p-rior to assembly of the cap and socket; and

FIG. 3 is a view similar to FIG. 2, but with the members assembled..

Referring now to the drawings, ythe reference numeral 10 designates a connector receptacle and the reference numeral designates a complementary connector plug for laxially mating with receptacle 10.

Receptacle 10 is provided with a rigid, generally cylindrical shell 11 in which la resilient dielectric body 12 is securely positioned. Body 12 can be formed by molding it in shell 11 or it may be separately molded and subsequently Iinserted into shell 11 in a conventional manner. Plug 20 is similarly provided with a generally cylindrical shell 21 in which is molded a resilient dielectric body 22.

Each of the resilient bodies 12 and 22 is provided with a plurality of parallel, longitudinally disposed bores 13 and 23, respectively of which only three are shown for the sake of clarity. Within bore 23 is pin contact 24 and within bore 13 is the mating socket contact 14.

In order to assembly receptacle 10 in plug 20 the two units are coupled by inserting the leading portion of shell 21 into annular cavity 15 defined by shell 11 and coupling nut 16. Coupling nut 16 is then turned so that threads 17 engage with threads 25. As the coupling nut 16 is tu-rned pins 24 align with sockets 14 making electrical contact thereby. The nut is turned until the end faces of bodies 12 and 22 are compression mated whereby air, moisture and dust are excluded from coming into contact with the pin and socket surfaces. Appropriate wires are soldered to solder joints 18 and 28 and conventional back shells are used to engage threads 19 Patented Nov. 22, 1966 and 29 for sealing the wire bundles from the external environmental conditions.

A problem arises, however, when the plug and receptacle are disconnected during assembly or servicing in that moisture and dust can then accumulate on the conductive contacts impairing the electrical conductivity thereof. However, by employing the connector cap 30 of the present invention as shown in FIGURE 2 the aforementioned problems of atmospheric contamination of the contacts and physical misalignment of the contacts is eliminated- This connector cap or protector can be made from any appropriate material such as silicone, urthane or neoprene and is provided with an annular portion 31 having an inside straight surface 32 and an outside tapered surface 33- however, the reverse is permissible with the inside surface being tapered. The outside surface 33 has threads 35 formed thereon for engagement with threads 17 of the receptacle. The leading edge of annular portion 31 is rounded in order that it will form a seal upon contacting ange 41 on the recepta-cle shell 11.

In order to use the connector cap of the present invention the leading edge of annular por-tion 31 is inserted into cavity 1S and coupling nut 16 is turned in order tov engage thread 17 with threads 35 thereby pulling the connector cap into the annular cavity 15. An important aspect of the present invention is the taper of annular portion 31 of the protector 30. The portion 31 has a thickness D at the base whereas the annular cavity 15 is uniformly of width d. The web thickness of the base of portion 31, D is greater than the width, d, of annular cavity 15. However the leading edge of portion 31 is somewhat smaller than d permitting ready insertion of the connector cap int-o the annular recess 15. As the coupling nut is turned and portion 31 is drawn into cavity 15, the elastic material of which the connector cap is made undergoes compression at the point where the thickness of member 31 becomes greater than d. Consequently elastic ow results causing the elastic material to ll up all voids. The protector is designed so that when the coupling nut is completely turned down and its leading edge 42 contacts lip 36 of the protector, leading portion 34 of the protector comes into contact with iiange 41 of shell 11 thereby forming a seal between 34 and 41 and between 42 and 36 of the receptacle and protector. Moreover, the threaded surfaces 17 .and 35 are engaged along their entire length forming a seal which is extremely impervious to air seepage and dust.

Referring now to FIGURE 3 the protector cap of the present invention is shown in place with the receptacle and coupling nut 16 having been completely turned down, the elastic material of the protector has flowed into all irregularities in the threads and surfaces. This forms a positive seal 51 all along the threaded surfaces and also forms an effective seal at points 52 and 53. Moreover because of the compression of the material in void 15 the elastic material forms an effective seal at contact point 54 between the inside surface 32 of the protector cap and the outside surface of shell 11. As a result the protector cap forms a seal which is impervious to dust, moisture and other contaminants. In addition portion 36 provides protector cap 30 with an overall diameter substantially greater than that of the diameter of the receptacle producing a shock absorbing surface to protect the socket contacts from injury and misalignment due to mishandling and rough treatment. Also as noted in FIGURE 3 a protrusion 37 may be provided on the connector cap which is integral thereto for the purpose of retaining a bead or link chain attachment. In this way the end cap with the receptacle attached may be tied to a location where it is out of the way during termination.

Although Various minor modications may be suggested by those versed. in the art, it should be understood that modifications and variations may be effected without departing from the scope and novel concepts of the present invention.

I claim:

An electrical connector of the axially connecting type having a shell and an outside coupling nut with inside threads which shell and nut form an annular cavity having a uniform predetermined width and a predetermined volumetric capacity in combination with a protector comprising a hollow cylinder made up of elastic material having la first open end Where the thickness of the cylinder is greater than said predetermined Width, a second open end Where the thickness of the cylinder is less than said predetermined width, an inside surface, an outside surface, a gradually tapered. wall thickness and a total volume substantiallyA equal to said volumetric capacity, a disc-shaped closure having a diameter greater than the outside diameter of said first open end, said 4 closure Ibeing integral With said first open end thereby closing it, said outside surface containing threads for threaded engagement with said coupling nut and said inside surface being substantially smooth for engaging the outside surface of said shell.

References Cited by the Examiner UNITED STATES PATENTS BOBBY R. GAY, Primary Examiner.

2() PATRICK A. CLIFFORD, Examiner.

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