Self locking male and female connectors for electrical cords

An electrical connector apparatus has a male connector and a female connector. The male connector has a first housing. There is a plurality of first wiring terminals in a first wiring chamber and a plurality of prongs electrically connected to the first wiring terminals. A first T-shaped longitudinal locking foot is attached to a first outer surface of the first housing. A female connector is removably attached to the male connector. The female connector has a second housing. A second wiring chamber is in the second housing. A plurality of second wiring terminals is in the second wiring chamber. There is a plurality of prong receptors electrically connected to the second wiring terminals. These prong receptors are located in the second housing. A first T-shaped longitudinal locking channel is attached to a second outer surface of the second housing to slidingly and removably receive the first T-shaped longitudinal locking foot. A second T-shaped longitudinal locking channel is attached to the third outer surface of the first housing to slidingly and removably receive the second T-shaped longitudinal locking foot on the fourth outer surface of the second housing. A second T-shaped longitudinal locking foot is attached to the second outer surface of the second housing to slidingly and removably receive the first T-shaped longitudinal locking channel.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to electrical cord connectors, in general, and, 
specifically, to interlocking male and female connectors to reduce the 
chance of accidental separation of one from the other. 
2. Description of the Related Art 
Both homeowners and contractors have suffered from the inconvenience of 
connector separation when they try to get the electrical appliance or 
tool, plugged into either a wall plug or into one or more extension cords, 
to reach just another couple of inches only to have the appliance or tool 
shut off. Many connectors have been modified in several different ways in 
the past. They have been tied together, looped around each other, wired 
together and placed in containers that try to force the two connectors to 
remain together. 
U.S. Pat. No. 5,069,634 to M. J. Chiarolanzio on Dec. 3, 1991 for a Snap 
Lock Extension Cord and Power Tool Connector describes a female connector 
having a lip on each of two prongs that are releasably inserted into a set 
of locking slots in the male connector. 
U.S. Pat. No. 5,129,836 to N. E. Ursich on Jul. 14, 1992 for a Self-Locking 
Female Receptor for Electric Cord shows a female receptor into which a 
male receptor may be releasably locked by balls, located in the female 
receptor, biased into the holes in the male prongs. 
U.S. Pat. No. 5,139,438 to D. P. Gaffney on Aug. 18, 1992 for an Extension 
Cord Receptacle describes a female connector having legs connected in a 
"V" with the free ends springingly biased apart to frictionally grasp the 
prongs of the male connector. 
U.S. Pat. No. 5,194,013 to M. Propp on Mar. 16, 1993 for a Lock Plug shows 
a locking electrical male plug having a key to cause an end on the prongs 
to expand within a female receptor to reduce accidental removal of the 
male plug from the female receptor. 
U.S. Pat. No. 5,219,304 to C. H. Lin on Jun. 15, 1993 for an Electrical 
Plug describes a male plug that keeps the prongs and wires leading to them 
separate from each other by molded plastic channels. The plug is two-piece 
to assist in connecting the wires to the prongs. 
The present invention recognized the problem inherent in many of these 
devices. Many of them tried to restrain two linearly connected end-pieces 
from separating when a linear force was applied. They did not address the 
problem at the root of the problem which was the inadequate initial design 
of the basic connectors. The present invention redistributes the force 
vectors usually found in the common connector when its two ends are pulled 
180 degrees away from each other and is designed to cause the connectors 
to become even more secure in their connection as the opposing linear 
forces are applied. Greater resistance to disconnection must be overcome 
before the present connectors can be separated. As the electrical cords 
are pulled apart in opposite directions, the force of separation must be 
large enough to rotate the connectors and to pull the prongs out of the 
receptors from a position angular to the plane of the opposing linear cord 
forces to a position where the prongs and receptors are parallel to the 
plane of the cord forces. To supplement the resistance of connector 
separation in the present invention, there are interlocking feet and 
channels. This results in a male and female connector that will often bind 
the two connector together even tighter until a force great enough to 
completely tear the two connectors apart is reached. 
SUMMARY OF THE INVENTION 
In one aspect of the present invention, an electrical connector apparatus 
for an electrical cord has a male connector and a female connector. The 
male connector has a first housing and a plurality of first wiring 
terminals in the first housing. There is a plurality of prongs 
electrically connected to the first wiring terminals. The prongs partially 
extend outside the first housing. There is a T-shaped longitudinal locking 
foot attached to an outer surface of the first housing. A female connector 
is removably attached to the male connector. 
The female connector has a second housing and a plurality of second wiring 
terminals in the second housing. There is a plurality of prong receptors 
electrically connected to the second wiring terminals. The prong receptors 
are housed inside the second housing. There is a T-shaped longitudinal 
locking channel attached to an outer surface of the second housing to 
slidingly and removably receive the T-shaped longitudinal locking foot. 
In another aspect of this invention, an electrical connector apparatus for 
an electrical cord has a male connector. The male connector has a first 
housing and there is a first wiring chamber in the first housing. There is 
a first wiring chamber cover removably covering the first wiring chamber 
and the cover is removably connected to the first housing. A plurality of 
first wiring terminals are in the first wiring chamber. There is a 
plurality of prongs electrically connected to the first wiring terminals. 
The prongs partially extend outside the first housing. A T-shaped 
longitudinal locking foot is attached to an outer surface of the first 
housing. There is a female connector removably attached to the male 
connector; 
The female connector has a second housing. There is a second wiring chamber 
in the second housing. A second wiring chamber cover removably covers the 
second wiring chamber and is removably connected to the second housing. 
There is a plurality of second wiring terminals in the second wiring 
chamber. A plurality of prong receptors, to removably receive the prongs, 
is electrically connected to the second wiring terminals. The prong 
receptors are located in the second housing. A T-shaped longitudinal 
locking channel is attached to an outer surface of the second housing to 
slidingly and removably receive the T-shaped longitudinal locking foot. 
It is an object of this invention to provide a male and female connector 
for an electrical cord that reduces the possibility of an accidental 
disconnection of a male connector of this invention from a female 
connector of this invention. 
It is also an object of this invention to provide a female adaptor 
connector that will allow the user to connect the male connector of this 
invention to a standard female wall or similar receptacle.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to FIGS. 1 through 8, an electrical connector apparatus 10 for an 
electrical cord 100 is shown and described that has a male connector 12 
and a female connector 13. The housing and covers of the male and female 
connectors are preferably made of a molded impact resistant, 
nonconductive, insulative plastic material which may also be resilient. 
The male connector 12 has a first housing 14. There is a first wiring 
chamber 15 in the first housing 14 having a first wiring chamber cover 16 
that removably covers the first wiring chamber 15 and is removably 
connected to the first housing 14 preferably by threaded fasteners 17. 
There is a plurality of first wiring terminals 18 in the first wiring 
chamber 15 and a plurality of connector prongs 19 electrically connected 
to the first wiring terminals 18 either by conductor wires 20 or each 
terminal and associated prong may be an integral piece. The connector 
prongs 19 partially extend outside the first housing. A first T-shaped 
longitudinal locking foot 21 is attached to (preferably an integral molded 
part) a first outer surface 22 of the first housing 12. The female 
connector 13 is removably attached to the male connector 12. 
The female connector 13 has a second housing 23. There is a second wiring 
chamber 24 in the second housing 23. A second wiring chamber cover 25 
removably covers the second wiring chamber 24 and the cover is removably 
connected to the second housing 23. The cover 25 is preferably attached by 
threaded fasteners 26. There is a plurality of second wiring terminals 27 
in the second wiring chamber. These wiring terminals 27 like those wiring 
terminals 18 in the first housing 12 allow the wiring 101 from the 
electrical cord 100 to be secured by threaded fasteners. There is a 
plurality of prong receptors 28 electrically connected to the second 
wiring terminals 27. These prong receptors are located in the second 
housing 13 and removably receive the connector prongs 19. These prong 
receptors 28 are connected to the wiring terminals 27 by either by 
conductor wires or each terminal and associated prong receptor 28 may be 
an integral piece. 
The present invention 10 presents a novel way of reducing the chance of the 
first housing 14 and second housing 23 from separating at an undesired 
moment. A first T-shaped longitudinal locking channel 29 is attached to 
(usually a molded integral part) a second outer surface 30 of the second 
housing 23 to slidingly and removably receive the first T-shaped 
longitudinal locking foot 21. There is a second T-shaped longitudinal 
locking channel 31, attached to the third outer surface 32 of the first 
housing 14, to slidingly and removably receive a second T-shaped 
longitudinal locking foot 33 on the fourth outer surface 34 of the second 
housing. The second T-shaped longitudinal locking foot 33 is attached to 
the fourth outer surface 34 of the second housing 23 to slidingly and 
removably receive the first T-shaped longitudinal locking channel 21. 
The female connector 13A may be modified to allow the electrical connector 
apparatus 10A to be plugged into a wall or similar socket (not shown). The 
female connector 13A, in this embodiment 10A, (Like elements have like 
reference numbers with an "A" added thereto.) is removably attached to the 
male connector 12 as shown in FIG. 3. This female connector 13A has a 
second housing 23A similar to the second housing 23 described above but 
without the wiring chamber or cover. There is a plurality of adaptor 
prongs 35 in the second housing 23A. The adaptor prongs 35 partially 
extend outside the second housing 23A in order to be plugged into the wall 
or other electrical socket. A plurality of prong receptors 28A are 
electrically connected to the adaptor prongs 35 in the same manner as the 
receptors 28 are connected to the wiring terminals described above. The 
prong receptors 28A are located within the second housing 23A. The prongs, 
receptors and wiring terminals may be made of any suitable conductive 
material such as copper. 
In operation, the feet 21 and 33 and channels 29 and 31 of the male 
connector 12 and the female connector 13 are aligned and the feet eased 
into the channels. As the feet are fed into the channels, the connector 
prongs 19 are aligned with and started into the open end 38 of the 
receptors 28 until the male abutting surface 36 intimately abuts with the 
female abutting surface 37. As the two connectors are pulled away from 
each other, the force tends to secure the two connector even tighter until 
the force pulls the connectors in a rotative, nonlinear motion. Even then, 
the connectors will tend to bind until the force on the prongs and 
receptors are enough to pull them away from each other in almost an 180 
degree relationship. 
The foregoing descriptions and drawings of the present invention are 
explanatory and illustrative only, and various changes in shape, sizes and 
arrangements of parts as well certain details of the illustrated 
construction may be made within the scope of the appended claims without 
departing from the true spirit of the invention.