Electrical connector protective device

A protective cover for a standard multiple-pin electrical connector receptacle of the type used to connect a trailer and a prime mover vehicle, the receptacle having a generally cylindrical body having at least one longitudinally extending orientation key protruding outwardly from the cylindrical body and a generally flat end having multiple electrical connecting elements recessed therein and an additional terminal protruding therefrom. The cover is comprised of a cup-shaped housing having an open end and a closed end and a cylindrical wall therebetween, the cylindrical wall having an inner surface and an outer surface, the diameters of the inner surface of the cylindrical wall and the cylindrical body being so related so that when assembled a friction fit exists therebetween to provide the principal means for retaining the cover in assembled relation to the receptacle. There is a longitudinally extending slot in the inner surface of the cylindrical wall of the housing for receiving the orientation key when the cover is assembled with the receptacle.

FIELD OF THE INVENTION 
The present invention relates generally to standard electrical connector 
receptacles used to electrically interface between a prime mover vehicle, 
such as a car or truck, and a towed vehicle, such as a trailer. More 
particularly, the present invention relates to a unitary, molded plastic 
protective cover for electrical connector receptacles which, when the 
receptacle is not engaged with the associated plug, provides protection to 
the receptacle from environmental conditions. 
BACKGROUND OF THE INVENTION 
The general idea of protecting disengaged electrical connectors and 
receptacles from environmental conditions is well known. Prior art 
solutions typically have focused on providing either a friction fit cover 
or a cover for wall mounted receptacles with rather complex locking means. 
None of the prior art solutions, however, address the problem of a 
protective cover for standard multiple-pin electrical connector 
receptacles of the type used in towing operations. Thus, there remains a 
need for a simple, inexpensive cover that will provide protection from 
environmental conditions for such standard electrical connector used in 
towing operations when the receptacle is disengaged for the associated 
plug. 
SUMMARY OF THE INVENTION 
Generally, the present invention is a protective cover for a standard, 
multiple-pin electrical connector receptacle of the type used to connect a 
trailer and a prime mover vehicle, wherein the receptacle includes a 
generally cylindrical body having at least one longitudinally extending 
orientation key protruding outwardly from the cylindrical body and a 
generally flat end having multiple electrical connecting elements recessed 
therein and an additional terminal protruding therefrom. The cover is 
essentially a cup-shaped housing having an open end and a closed end and a 
simple cylindrical wall therebetween. The cylindrical wall has an inner 
surface and an outer surface. The diameters of the inner surface of the 
cylindrical wall and the cylindrical receptacle body are so related so 
that when assembled a friction fit exists therebetween. A longitudinally 
extending slot in the inner surface of the cylindrical wall of the housing 
receives the orientation key when the cover is assembled with the 
receptacle. The cover further includes a plurality of the spaced tabs 
adjacent to the open end of the housing and extending outwardly from the 
outer surface of the cylindrical wall for aiding in the assembly and 
disassembly of the cover and the receptacle. There is preferably a hole in 
at least one of the plurality of space tabs for attaching a tether. One 
end of the tether is connected to the tab of the cup-shaped housing and 
the other end is connected in any convenient manner to the trailer to 
maintain the receptacle above the ground and out of the mud and dirt. The 
cover may further include a recess protruding outwardly from the closed 
end of the housing for receiving the additional protruding terminal of the 
receptacle when the cover is assembled with the receptacle. 
It is the primary object of the present invention to provide a cover for a 
standard electrical connector receptacle used in towing operations that 
will provide protection from environmental conditions when the receptacle 
is disengaged from the associated plug. 
It is another object of the present invention to provide an electrical 
connector receptacle cover that is simple in design and therefore easily 
manufactured in a reasonably inexpensive manner, is reliable in use, and 
is easily manipulated as part of the normal cover to receptacle mounting 
procedures to effect its secure retention thereto. 
These and other aspects of the present invention will become apparent to 
those skilled in the art after a reading of the following description of 
the preferred embodiment when considered with the drawings.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT 
In the following description, like reference characters designate like or 
corresponding parts throughout the several views. Also in the following 
description, it is to be understood that such terms as "forward," 
"rearward," "left," "right," "upwardly," "downwardly," and the like are 
words of convenience and are not to be construed as limiting terms. 
Referring now to the drawings in general and FIG. 1 in particular, it will 
be understood that the illustrations are for the purpose of describing a 
preferred embodiment of the invention and are not intended to limit the 
invention thereto. FIG. 1 illustrates the problem of an exemplary standard 
multiple-pin electrical connector receptacle 11 that is disengaged from 
the associated plug and is exposed to environmental conditions. Such 
exposure to environmental conditions can result in moisture entering the 
metal recesses of the receptacle 11 and corroding the recesses, and/or the 
accumulation of debris in the recesses of the receptacle 11, either of 
which can cause a failure of the receptacle 11 when engaged with the 
associated plug. 
FIGS. 2 and 3 show the preferred embodiment of the protective cover 10 in 
association with the exemplary receptacle 11. The exemplary connector or 
receptacle 11 is of a type available from Joseph Pollack Corporation of 
Boston, Mass. as Trailer End Plug Model Nos. 12-702 and 12-706. The 
receptacle 11 has a generally cylindrical body 2 with a flat end 
containing a plurality of spaced recesses 8 for receiving the 
corresponding pins of the associated electrical plug. An additional 
terminal 6 is provided that protrudes outwardly from the flat end of the 
body 2 and is for an auxiliary electrical circuit. A longitudinally 
extending orienting key 4 on the body 2 is provided for correctly 
orienting the alignment of the spaced recesses 8 with the corresponding 
pins of the associated electrical plug when the plug is inserted into the 
receptacle 11. The receptacle 11 is a standard electrical component known 
in the art, and is not, per se, part of the present invention. Other 
conventional connectors and receptacles of this general type may include 
more or less pins and recesses, but are included within the scope of the 
invention. 
A tether 22 is provided for suspending the cover 10 about the ground when 
the cover is assembled with the electrical connector receptacle 11. 
FIGS. 4 and 5 show the improved protective cover 10 that is made of a 
unitary, molded plastic cup-shaped housing 12. Such a construction allows 
for easy and inexpensive construction of the protective cover 10. The 
housing 12 has generally cylindrical inside walls that correspond in size 
and shape to the generally cylindrical body of the receptacle 11. The 
inside diameter of the housing 12 is approximately the same as the outside 
diameter of the receptacle 11 so that a friction fit is achieved when the 
cover 10 and the receptacle 11 are assembled. 
As best seen in FIG. 4, a slot or keyway 14 in the inner wall of the 
housing 12 extends longitudinally from the open end of the housing 12 to 
the integral closed end of the housing 12. The slot 14 receives the 
corresponding orientation key on the receptacle 11 when the protective 
cover 10 and the receptacle 11 are assembled. A plurality of tabs 16 
extend outwardly from the circumference of the open end of the housing 12. 
The tabs 16 allow for grasping the protective cover 10 when assembling or 
disassembling the protective cover 10 and the receptacle 11. At least one 
of the tabs 16 contains hole 20 for receiving one end of the tether 22. In 
the preferred embodiment, the tether 22 is connected at one end to the 
protective cover by inserting the first end of the tether 22 through the 
hole 20 and tying the first end so that the tether is secured to the 
protective cover 10. Other conventional means of securing the first end of 
the tether 22 to the protective cover 10 may be used. The second end of 
the tether 22 is secured by any conventional means to any object on the 
trailer that can support the weight of the receptacle 11 and the 
protective cover 10 so that the tether 22 can be easily secured and 
released. In the preferred embodiment, the second end of the tether 22 is 
releasably attached to the trailer hitch assembly. 
As best seen in FIGS. 5 and 6, the closed end of the housing 12 has a small 
recess 24 in the inside of the closed end of the housing 12 to receive a 
corresponding additional terminal 6 protruding from the electrical 
connector receptacle 11. The size and location of the recess 24 
corresponds to the size and location of the receptacle's 11 additional 
terminal 6 protruding nub so that the terminal 6 seats in the recess 24 
when the cover 10 and the receptacle 11 are assembled. 
In operation, when the receptacle 11 is disengaged from the associated 
electrical plug connected to the prime mover vehicle, such as a car or a 
truck, the open end of the protective cover 10 is simply fitted over the 
receptacle 11. The open end of the protective cover 10 must be oriented 
relative to the receptacle 11 so that the slot 14 is in alignment with the 
corresponding orientation key 4 of the receptacle 11. The receptacle 11 is 
then axially inserted into the protective cover 10 so that the slot 14 
receives the orienting key 4 and the recess 24 receives the terminal 6. 
The user may grasp the tabs 16 to aid in the insertion or withdrawal of 
the receptacle 11 into or from the cover 10. Once assembled, the friction 
fit between the cover 10 and the receptacle 11 prevents unintentional 
disengagement of the cover 10 and the receptacle 11. 
To further prevent the exposure of the receptacle 11 to environmental 
conditions, the first end of the tether 22 is connected to the cover 10. 
In the preferred embodiment, the tether 22 is attached to the cover 10 by 
inserting the first end of the tether 22 through a hole 20 on one of the 
tabs 16 and tying the tether 22 to the tab 16. The tether 22, however, can 
be secured to the cover 10 by any conventional means. The second end of 
the tether 22 is then releasably secured to the hitch assembly of the 
trailer so that the assembled cover 10 and receptacle 11 is suspended 
above the ground thereby preventing moisture and other foreign objects 
from entering the recesses 8 of the receptacle 11. 
Certain modifications and improvements will occur to those skilled in the 
art upon a reading of the foregoing description. By way of example, any 
conventional means can be used to attach the tether 22 to the assembled 
cover 10 and receptacle 11 and to the trailer hitch assembly. The tether 
22 also can be secured to any nearby stationary object that is capable of 
supporting the weight of the assembly of the cover 10 and the receptacle 
11. The cover 10 can be made of any material that is capable of protecting 
the receptacle 11 from environmental conditions. 
It should be understood that all such modifications and improvements have 
been deleted herein for the sake of conciseness and readability but are 
properly within the scope of the following claims.