U.S. patent number 3,787,948 [Application Number 05/241,909] was granted by the patent office on 1974-01-29 for wire nut wrench.
Invention is credited to Charles H. Runge.
United States Patent |
3,787,948 |
Runge |
January 29, 1974 |
WIRE NUT WRENCH
Abstract
A wrench for forming pigtail splices in wire nuts between
electrical conductors. The wrench has a plastic workhead in the
form of a relatively narrow block. There is a wire nut socket
running from top to bottom through the workhead, near one end. A
thin metal handle extends downwardly from the workhead near the end
opposite its wire nut socket end. To form a pigtail splice in a
wire nut with the wrench, the wire nut is fitted into the socket in
the workhead, and the bare ends of a pair of conductors are then
inserted as far as they will go into the wire nut. These conductors
are next held tightly with one hand near the wire nut, and the
workhead is spun rapidly around the axis of the wire nut socket, by
means of the wrench handle, with the other hand. This action twists
the wire ends into a pigtail splice and tightens the wire nut
firmly in place around the splice.
Inventors: |
Runge; Charles H. (Homeland,
CA) |
Family
ID: |
22912666 |
Appl.
No.: |
05/241,909 |
Filed: |
April 7, 1972 |
Current U.S.
Class: |
81/121.1; 29/758;
D8/21 |
Current CPC
Class: |
H01R
43/00 (20130101); Y10T 29/53257 (20150115) |
Current International
Class: |
H01R
43/00 (20060101); H05k 013/00 () |
Field of
Search: |
;29/23H,23HC,23HT,23HM |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Eager; Thomas H.
Attorney, Agent or Firm: Peter H. Firsht et al.
Claims
I claim:
1. Wrench means particularly suitable for the twisting of wire nuts
onto the ends of electrical conductors to form pigtail splices
therebetween, said wrench means comprising, in its operative form:
workhead means with structure defining a socket adapted to receive
a wire nut and hold it in nonrotatable relationship with respect to
said workhead means; and elongate handle means fixedly secured to
said workhead means, in spaced apart and axially parallel
relationship with said socket, so as to extend from the workhead
means in the opposite direction to that in which the receptive
opening of said socket faces; said workhead means and said handle
means being designed and relatively positioned to cooperate in a
way to permit the formation of a pigtail splice between the bare
ends of a pair of said electrical conductors in a wire nut when
said bar ends are firmly inserted into said wire nut, the wire nut
is fitted into said socket in said workhead means, the conductors
are held tightly near said wire nut with one hand and said handle
means is turned with the other hand so as to cause rotation of said
workhead means around the axis of said socket with the wire nut and
bare conductor ends positioned therein.
2. Wrench means in accordance with claim 1 in which the structure
defining said socket also defines diametrically opposite grooves in
the socket wall adapted to receive diametrically opposite vanes of
the type found on conventional wire nuts to prevent the relative
rotation of such a wire nut with respect to said workhead means
when the wire nut is fitted into said socket.
3. Wrench means in accordance with claim 2 in which said workhead
means is of molded plastic construction, said plastic being any
plastic material of sufficient strength and toughness to permit
said socket to hold said wire nut in nonrotatable relationship with
respect to said workhead means when said bar conductor ends are
being formed into a pigtail splice in the wire nut, and said handle
means is made of a metallic material of sufficient toughness and
durability to permit it to be turned with enough force so that said
pigtail splice is formed between said conductor ends in said wire
nut seated in said socket during this turning operation.
4. Wrench means in accordance with claim 3 in which the walls
defining said socket and said diametrically opposite grooves are
designed to receive any of a plurality of differently sized and
shaped wire nuts.
5. Wrench means in accordance with claim 4 in which said handle
means comprises an elongate bolt having a loose fitting cylindrical
sleeve disposed around its shank to facilitate the turning of said
handle means when said wrench means is in use.
6. Wrench means in accordance with claim 5 in which said elongate
bolt is threaded at one end and is fixedly secured to said workhead
means by threaded engagement with a tapped bore in the latter.
7. Wrench means in accordance with claim 6 in which said workhead
means is of plexiglass construction, and the parts of said handle
means are made of stainless steel.
8. Wrench means in accordance with claim 7 in which said handle
means includes a nut screwed onto the threaded end of said bolt to
provide tightening means to aid in a firm connection between said
workhead means and said handle means.
9. Wrench means in accordance with claim 8 in which the threads of
said bolt, said nut and said tapped bore in said workhead means run
in the proper direction to have a tightening effect on said handle
means when said wrench means is in use.
10. Wrench means in accordance with claim 9 in which said socket
runs from top to bottom through said workhead means.
Description
BACKGROUND OF THE INVENTION
This invention relates generally to means for quickly and easily
forming pigtail splices between electrical conductors, and more
particularly to a wrench of unique design for use in the rapid
installation of wire nuts on the bare ends of the conductors for
the formation of such pigtail splices.
In the course of their daily work, electricians have occasion to
make thousands of splices between conductor wires. Many of these
splices are of the so-called pigtail variety. Typically, a pigtail
splice is made by manually twisting a wire nut onto the bare ends
of a pair of conductors. As any electrician is aware, a wire nut is
a type of screw-on wire connector comprising a generally elongate
shell, typically made of plastic, enclosed at one end and having a
longitudinal hollow which is divided into two sections by an
annular ring or shoulder. The innermost of these sections has a
frusto-conical wall, converging toward the enclosed end of the wire
nut hollow, sized to snugly receive, at its larger end, the
stripped ends of two conductors, and fitted with a threaded insert.
The outermost of the two sections of the hollow has either a
generally cylindrical or flaring wall, and is of large enough cross
section to easily accommodate the insulated conductors, so that the
bare or stripped ends of these conductors can be inserted into the
wire nut far enough for a portion of the wire nut shell to surround
the wires adjacent their stripped ends to afford insulation against
accidental touching of the bare wire ends, or contact of the latter
with metal, or other conductive material, in the vicinity.
Typically, the wire nut shell is of nonconductive plastic
construction (although it can be formed from any other suitable
nonconductive material), and its threaded insert is made of metal.
As those skilled in the electrical arts are aware, a wire nut is
ordinarily employed by hand screwing it tightly onto the bare ends
of a pair of conductor wires until the threads of the wire nut
insert bite into the wire ends and sqeeze them together for good
electrical contact. Some twisting of the wires is also accomplished
by this procedure, which makes for enhanced contact therebetween.
Wire nuts are available in several sizes and shapes, but each is
characterized by a pair of diametrically outstanding fins to permit
better hand purchase of the nut while it is being tightened onto a
pair of conductors.
The conventional method of installing wire nuts described above is
slow, tedious, and difficult to perform, and often hard on the
fingers. Even an experienced electrician, especially when he is on
a big construction job where a tight schedule must be followed, can
end up with sore fingers after installing a few wire nuts in this
fashion. It is unwise to attempt to eliminate this problem through
the use of pliers on the nuts, since this practice can result in
cracking of the plastic wire nut shell and a consequent risk of
short circuits.
Wire nuts have been in common usage for some time, and, once
installed, they serve their purpose well. In spite of their long
period of use and acceptability in a vitally important segment of
the building industry, however, no one heretofore, to my knowledge,
has provided means for alleviating the present difficulties of
installing these extremely useful items of hardware. Consequently,
wire nuts are still laboriously installed by hand, in spite of the
work speed-up, greater ease of installation, and other, advantages
which would accrue from the use of more efficient means to
accomplish the same end.
SUMMARY OF THE INVENTION
The wire nut wrench of this invention is a simple and inexpensive
hand tool designed to firmly hold a wire nut in position while it
is being tightened onto the bare ends of a pair of conductor wires
to splice the wires together. Because of an inherent mechanical
advantage, the tool permits the wire nut tightening procedure to be
accomplished with great ease and rapidity. In its preferred form,
the wire nut wrench consists of a somewhat elongate, relatively
narrow, block-like body (generally referred to hereinafter as a
workhead) of molded plastic construction, having a socket running
from top to bottom therethrough, near one end, and a relatively
thin handle secured to the workhead so as to depend from the
underside of that body near its other end. The handle is long
enough to be easily grasped by hand, and is disposed in parallel
relationship to the axis of the socket. The workhead is fixed at
such length that the separation between the socket and handle axes
yields adequate leverage to permit relatively easy turning, or
spinning, of the workhead around the axis of the socket, by a
cranking motion of the handle, during usage of the tool.
The socket in the workhead of the wire nut wrench has diametrically
opposite grooves in its defining wall and is shaped to receive and
hold any of a plurality of wire nuts of various shapes and sizes
against rotational movement relative to the workhead, when the
latter is turned, or spun, by means of the wrench handle. The
wrench is easily employed to tighten a wire nut on the bared ends
of a pair of conductors by first fitting the nut into the socket in
its workhead; inserting the ends of the conductor wires into the
hollow in the wire nut as far as they will go; then, while holding
the insulated wires tightly near their stripped ends with one hand,
rapidly spinning said workhead around the axis of said socket, by
means of said handle, with the other hand. The spinning is
continued until the threads of the threaded insert in the wire nut
bite into the bared wire ends and twist them into close enough
contact for good electrical connection. This can be quickly and
easily accomplished by a skilled electrician with a few deft turns
of the wrench handle, as opposed to the slow, tedious, and tiring
way of installing wire nuts by the presently conventional
installation procedure.
It is thus a principal object of this invention to provide simple
hand tool means for the quick and easy preparation of pigtail wire
splices in wire nuts.
It is a second object of the invention to provide such means of
compact and inexpensive construction.
It is another object of the invention to provide such means usable
for long periods of time with substantially no pain or discomfort
to the user.
Other objects, features and advantages of the invention will become
apparent in the light of subsequent disclosures herein.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a side view of a preferred embodiment of a wire nut
wrench in accordance with this invention, a portion of a sleeve
component of the wrench being shown partially broken away, and
certain internal details being shown in dotted lines, for better
illustrative effect; and showing, additionally, a wire nut and
fragmentary segments of a pair of conductors with their ends bared
for splicing, the wire nut and conductor segments being depicted in
positions of approaching proximity to the wire nut wrench to
illustrate the manner of usage of the wrench.
FIG. 2 is a bottom view of the FIG. 1 wire nut wrench, certain
hidden features of the wrench being shown in dotted lines.
FIG. 3 is a top view of the wire nut wrench.
FIG. 4 is a fragmentary view, mostly in section, showing the main
parts of the FIG. 1 wire nut wrench.
FIG. 5 is a side elevation of a wire nut of different shape from
the FIG. 1 wire nut.
FIG. 6 is a side elevation of another wire nut of different shape
from that shown in FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Considering now the drawing in greater detail, there is shown
generally at 10 a preferred embodiment of a wire nut wrench in
accordance with this invention. Wire nut wrench 10 has a relatively
narrow, somewhat elongate workhead 12, and a thin, sturdy handle
14. The workhead 12 is of generally block-like form, and molded
plexiglass construction, although it could, if desired, be made of
any other plastic material having sufficient strength and toughness
for the purpose. The workhead of my novel wire nut wrench need not
necessarily be made of plastic, in fact, but can be formulated from
any other suitable material, such as, for example, a metal
(preferably a lightweight metal), within the scope of my
invention.
Handle 14 is formed from an elongate bolt 15 and a metallic sleeve
22. Sleeve 22 fits loosely around the bolt for a good portion of
its shaft length, as illustrated in FIG. 1. Bolt 15 has a head 18
at one end and is threaded for a relatively short distance from the
other end, the threads being shown at 20 in FIG. 4. There is a
tapped opening 21 running from top to bottom through workhead 12,
near one end, adapted to matingly receive the threaded end of bolt
15 to permit the attachment of handle 14 to the workhead. This
attachment is accomplished with the aid of a nut 24, which is
screwed down onto the threaded end of bolt 15 as far as it will go,
after the metallic sleeve 22 has been slipped down onto said bolt.
The sleeve is long enough to occupy most of the space between the
head 18 of the bolt and the tightened nut 24. The sleeve fits
loosely on bolt 15 to permit the turning of handle 14 with minimal
difficulty during usage of the wire nut wrench in the
below-described manner.
After sleeve 22 and nut 24 are positioned on bolt 15 as described
above, the bolt is screwed tightly onto the tapped opening 21 in
workhead 12 as the final step in the installation of handle 14. Nut
24 serves as a stop for workhead 12 to make it possible to obtain a
good tight fit between the workhead and wrench handle. For obvious
reasons, the threaded parts of the wrench are designed to cooperate
in such a way that handle 14 is inherently self-tightening when the
wrench is in service. The component parts of handle 14 can be made
of any tough, durable metal or alloy, such as, for example,
stainless steel. The handle is not limited to such a material of
construction, however, and can be fashioned from any material, or
materials, metallic or otherwise, having suitable properties for
the purpose.
There is a socket 16 in workhead 12, shaped to receive a wire nut
and hold it locked in position against rotational movement,
relative to the workhead, while wrench 10 is in use. Wire nuts, as
previously indicated, come in various shapes and sizes, but all are
characterized by the presence of the pair of diametrically
outstanding vanes referred to earlier, which serve to make the wire
nuts easier to install manually. A common type of wire nut is shown
at 36 in FIG. 1. Wire nut 36 has a pair of outstanding vanes 37
with enlarged outer end segments 39 which merge into smaller
segments 41 having outer edges convergent in the direction of the
enclosed end of the wire nut. FIGS. 5 and 6 show two other types of
wire nuts, at 38 and 40, respectively, with vanes noticeably
different in appearance from those of wire nut 36.
To permit socket 16 in workhead 12 to receive any of a variety of
wire nuts, as exemplified by wire nuts 36, 38 and 40, the defining
wall of the socket is divided into a generally cylindrical upper
segment 26, with diametrically opposite slots 34 extending radially
outwardly therefrom; and a lower, frusto-conical segment 28 with a
wall indented by a pair of relatively shallow slots 44 extending
downwardly from slots 34 and having bottoms which converge toward
the axis of the socket as they approach its lower end. The lower
segment 28 terminates at an annular, inturned lip or flange 30
which defines a constrictive opening 32 in the bottom of socket 16.
The lip or flange 30 has a pair of diametrically opposite notches
or indentations 46 positioned in alignment with the slots 44, as
best seen in FIGS. 2 and 3, for a purpose hereinafter made
clear.
As previously indicated, wire nut wrench 10 is employed as a tool
for the quick and easy twisting of a wire nut onto the bared ends
of a pair of conductors to splice the conductors together. This
twisting is accomplished by first inserting the bared ends of the
conductors into the receptive hollow in the wire nut as far as they
will go, in the direction and manner made clear in FIG. 1 which
shows such a pair of conductors 48 in approaching proximity to the
hollow opening in wire nut 36. The internal configurations of wire
nuts such as those described above, and illustrated in the drawing,
are well known to those skilled in the art, hence are not
illustrated herein. Suffice it to say that each of the wire nuts
has an inner segment containing a threaded insert, that portion of
wire nut 36 containing the insert being pin-pointed by the numeral
42 in the drawing.
After the bared ends of the conductors have been inserted into the
aforesaid wire nut, the latter is, in turn, inserted into socket 16
of the workhead 12. FIG. 1 shows the wire nut 36 aligned for proper
insertion into socket 16, it being noted that vane segments 44 and
39 of vanes 37 are respectively aligned with slots 44 and 34 in
that socket, to permit mating interfit between the wire nut and
socket. After the wire nut has been fitted into socket 16, the
conductor wires (38) are firmly grasped near the wire nut (where
they are, of course, insulated) with one hand, and handle 14 is
grasped with the other hand and turned so as to cause the rapid
rotation of workhead 12 around the axis of socket 16. A few quick
turns of the wrench, in this fashion, causes the wire nut to twist
itself onto the bared ends of the conductor wires, after which the
wires are retained firmly in the wire nut by the biting threads of
its threaded insert. The interfit between the vanes on the wire nut
and the receptive slots for those vanes in socket 16 prevents
rotation of the wire nut relative to workhead 12 when the tool is
being turned as described.
It will be evident that wires can be spliced in a wire nut similar
to wire nut 38 or 40 by a procedure such as that described above
for the splicing of wires in wire nut 36. Thus, the bare wire ends
are inserted into the wire nut of either of these types, and the
latter is then fitted into socket 16 so that its vanes are
accomodated by appropriate slots in the socket wall. Workhead 12 is
then spun around the axis of socket 16, by means of handle 14,
until the wire nut is twisted onto the wires. It will be apparent
from the teachings herein, and the accompanying drawing, that wire
nuts of differing sizes, as well as shapes, can be made to fit into
socket 16 to permit use of wrench 10 for the forming of wire
splices in the above-described manner.
While my novel wire nut wrench has been herein described and
illustrated in what I consider to be a preferred embodiment, it
will be appreciated by those skilled in the art that my invention
is not limited to that particular embodiment, but is broad enough
in concept to encompass all modifications thereof incorporative of
the structural and functional essence of the invention as taught
herein. Certain of these modifications have already been mentioned,
and others will occur to those skilled in the art in the light of
present teachings. Exemplary of the latter are noncritical
variations of the shapes, sizes and relative positions of parts or
features of the illustrated wrench; the elimination of certain
features of the tool not critically essential to its proper use and
functioning; the inclusion of nonillustrated features of a useful
character, not essential to proper use and functioning of the tool,
in its design; etc. More specific examples of such modifications
include wrenches with corresponding slots in their wire nut socket
walls offset 90.degree. from slots 34 and 44 in socket 16 of wrench
10; wrenches having no sleeves corresponding to sleeve 22 on their
handles; wrenches with permanently attached, rather than removable,
handles; etc.
Finally, while I have herein stressed the pigtail splicing utility
of my novel wrench, it will be understood that the wrench is not
necessarily limited to that particular field of use, and can be
employed in any capacity to which its unique capability suits it.
It is emphasized, in final summary, that the scope of the present
invention extends to all variant forms thereof encompased by the
language of the following claims.
* * * * *