Note: Descriptions are shown in the official language in which they were submitted.
CA 02622237 2014-12-29
ELECTRICAL CONNECTOR ASSEMBLY
WITH FRUSTRO-CONICAL SNAP FIT RETAINING RING
FOR ENHANCING ELECTRICAL GROUNDING OF THE
CONNECTOR ASSEMBLY TO AN ELECTRICAL BOX
AND INSTALLATION TOOL THEREFOR
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Field of the Invention
This invention is directed to a further advancement in
the field of electrical connector assemblies of the kind
utilizing a snap fit retaining ring circumscribing the
outlet end of a connector body for effecting a snap fit
connection to an electrical box of the types heretofore
described in U.S. Patent 6,860,758, and co-pending
application Serial No. 10/790,283 filed March 1, 2004 for
Snap Fitting Electrical Connector; and in a co-pending
Application Serial No. 11/028,373 filed January 3, 2005.
More specifically, this application in addition
relates to a snap fit electrical connector assembly having
a construction for facilitating the connection of the
connector assembly and associated cable, wire conductor and
the like to an electrical box. The connector assembly
includes a connector body and a readily detachable, outer
frustro-conical, snap fit retaining member or ring
circumscribing the outer surface of the outlet end of a
connector body. In one form of the invention the frustro-
conical retaining ring is formed for use with a tool to
enhance its connection to an electric box. In another
form, the frustro-conical retaining ring can be formed so
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that it can be connected to an electric box without the use
of any tool. The connector assembly may also be utilized
with or without a unidirectional cable or wire retainer
associated with the inlet end of the connector body for
positively securing a wire, cable or conductor to the inlet
end so as to prohibit any unintentional separation of the
wire, cable or electrical conductor from the connector
assembly.
This invention further contemplates a snap fit
connector assembly that utilizes a frustro-conical
retaining ring constructed so as to enhance or maximize the
electrical continuity for grounding purposes between the
electrical connector assembly and the electrical box to
which it is connected.
BACKGROUND OF THE INVENTION
Electrical connectors are commonly used for attaching
electrical conductors, cables, wires, electrical metal
tubing (EMT) or the like to an electric box, e.g. a
junction box, outlet box, switch box, fuse box, or other
similar type of electric box or an electrical mounting
panel. Such known electrical connectors are either of a
type that are secured to an electric box or electrical
panel by a threaded lock nut or by means of a circular snap
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fit retaining ring of the type disclosed, for example, in
U.S. Patents 6,860,758; 6,444,907; 5,189,258; 5,266,050;
5,171,164; 2,744,769 and 1,483,218. Reference is also made
to U.S. Patent 6,768,057 which is directed to a right angle
type connector formed of a pair of sheet metal stampings
fitted together and secured to an electrical box with a
snap fit arrangement. Connectors formed as connector caps
which are adapted to be fitted over the end of a conductor,
cable or wires, such as disclosed in U.S. Patent 4,880,387,
are also known. Various other known efforts to facilitate
the connection of an electrical conductor to an electric
box are evidenced by U.S. Patents 6,043,432; 6,080,933;
6,114,630; 6,133,529; 6,194,661; 6,335,488; 6,352,439;
6,355,884; 6,444,907; 6,555,750; 6,604,400; 6,670,553;
6,737,584; 6,682,355; 6,780,029 and 6,849,803.
While "snap fit" connectors have been in use for some
time, the attachment of such "snap-fit" connectors to an
electric box which is concealed in a finished wall is
difficult, if not impossible. This is because such "snap
fit" retaining rings are formed of spring steel so that the
locking tangs, due to the inherent nature of the spring
steel, require a good amount of force to flex the locking
tangs in order to pass through the conventional knock-out
hole to properly seat and lock the connector to a knockout
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hole of an electric box. For this reason, the installer or
user does not have generally sufficient access to the
connector assembly so as to apply the necessary force to
manually pull the leading end of the connector assembly
through the knockout hole due to the relative rigid
flexibility of the locking tangs in order to seat and lock
the connector assembly to the knockout opening. Usually,
the installer or user has to exert a severe pulling force
on the wires extending through the connector assembly to
seat and lock a snap-fit connector assembly in the knockout
hole of an electric box. Applying such pulling force
directly on the wires to lock a snap-fit connector assembly
to an electric box could seriously damage the conducting
wires.
It has also been noted that the typical metallic
electrical boxes, e.g. wall boxes, ceiling boxes, junction
boxes, electrical panels and the like, which are provided
with knock-out openings or holes for receiving an
electrical connector assembly, have varying thicknesses.
As a result, the degree of electrical grounding that can be
attained between the electrical connector assembly and an
electric box can vary from box to box. Heretofore,
electrical connector assemblies utilizing a so-called
external snap fit ring to effect a snap fit connection to
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an electric box were formed with circumferentially spaced
grounding tangs arranged to engage the internal periphery
of the knock-out opening provided in such electric boxes to
effect the required grounding. As a result, such
circumferentially spaced grounding tangs provided only a
minimum degree of contact between the electrical connector
retainer ring and the metallic electric box or panel for
effecting any electrical grounding. The amount of
electrical grounding achieved by such grounding tangs may
vary from box to box, depending upon the material thickness
of a given electric box or panel. As a result, a positive
or desired amount of electrical grounding, attained between
the connector assembly and the electric box, will vary from
installation to installation.
SUMMARY OF THE INVENTION
An object of this invention is to provide an
electrical connector with a frustro-conically shaped
retaining ring having integrally formed locking tangs and
electrical grounding tangs.
Another object of this invention is to provide an
electrical connector assembly having a snap fit retaining
ring constructed to enhance or maximize the electrical
grounding between an electrical connector assembly and an
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electric box or panel when such snap fit connector is
secured to a metallic electric box or panel.
Another object of this invention is to provide an
electrical connector with a frustro-conically shaped
retaining ring having integrally formed locking tangs and
electrical grounding tangs wherein the grounding tangs
circumscribe a major portion or the entire periphery of the
trailing end of the frustro-conical retaining ring that is
in contact with the internal periphery of a knock-out hole.
Another object of this invention is to provide for an
electrical connector assembly that includes an electrical
connector body having an outlet end with a frustro-conical
outer surface having a complementary frustro-conical
retaining ring that is readily fitted to and retained on
the outlet end portion of the connector body.
Another object is to provide a connector assembly
having an outlet end about which there is disposed a
retaining ring having an opening sized to receive the
working end of a tool functioning as a lever to transmit a
pulling force on the connector and associated retaining
ring to pull the connector and associated retaining ring
through a knockout hole to seat and lock the connector
assembly to the electric box with a minimum of effort or
force.
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,
Another object is to provide a unique tool for
engaging an enlarged retaining slot formed in the retaining
ring having laterally outwardly bent locking tangs wherein
the tool functions as a lever for exerting a pulling force
on the connector and associated retainer ring to seat and
lock the same to an electric box.
Another object is to provide a connector assembly
comprising a connector body having an outlet portion free
of any retaining flange, and an associated snap fit
retainer ring circumscribing the outlet end portion.
Another object is to provide a retaining ring having a
face portion with outwardly flaring circumscribing arms or
sides having locking and grounding tangs that are formed
out of a surface of the respective arms or sides.
Another object is to provide a retaining ring, adapted
to be fitted onto the outlet end of a connector body, and
having a frustro-conical shape with a first series of tangs
for securing the connector body relative to an electrical
box and a second series of tangs for affecting a positive
electrical ground with an associated electrical box.
Another object is to provide a frustro-conically
shaped retaining ring that can be readily formed from a
blank of spring steel.
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Another object is to provide an electrical connector
assembly having a connector body with a frustro-conical
outer retainer ring circumscribing the outer surface of the
connector body outlet end and a unidirectional retainer
ring or sleeve associated with the inlet end of the
connector body for securing an electrical wire or conductor
thereto.
Another object is to provide an electrical connector
assembly that includes an internal unidirectional sleeve
insert for frictionally retaining a wire conductor to the
connector assembly so as to prevent any unintentional
separation of a wire conductor therefrom.
Another object is to provide an electrical connector
assembly with an outer frustro-conical retainer ring for
attaching a connector assembly to an electrical box with a
snap fit and including an inner unidirectional retainer
ring or sleeve for securing a wire conductor thereto in a
manner to prohibit any unintentional separation of the wire
conductor from the connector assembly.
Another object is to provide an electrical connector
with an improved wire retainer sleeve or ring whereby a
wire conductor is positively secured thereto simply by
inserting the wire conductor into the connector so that
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unintentional separation of the wire conductor from the
connector assembly is prohibited.
Another object of this invention is to provide an
electrical connector with a wire retainer ring whereby a
helical wound wire conductor can be secured upon mere
insertion or threading the armored conductor wire into the
wire retainer ring to prohibit any unintentional separation
of the wire conductor from the electrical connector.
Another object is to provide or an electrical
connector assembly that is relatively simple to fabricate
and positive in operation.
Another object of this invention is to provide an
electrical connector assembly having an outer frustro
conical retainer ring for positively connecting the
connector assembly to an electrical box and having multiple
inlet ends, each fitted with an internal wire retainer ring
for unidirectional locking therein a wire conductor in each
of the multiple inlets.
Another object of this invention is to provide an
improved multiple cable or wire conductor connector
assembly that is relatively simple in structure, easy to
assemble and having a minimum of component parts.
Another object is to provide a connector assembly
having multiple inlet ends, each inlet end being fitted
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with internal spring steel internal retaining ring arranged
to maximize electrical conductivity or grounding.
Another object is to provide an electrical connector
assembly having an outer frustro-conical retainer ring
forming a snap fit attachment to an electric box or panel
and having an improved unidirectional wire conductor
retainer in the form of a retaining finger projecting into
the inlet end of a connector body so as to provide a snap
fit wire retention device which prohibits any unintentional
separation of the wire conductor form the connector.
Another object is to provide a relatively simple and
positive acting snap fit wire conductor retaining device
for securing and retaining a wire conductor to an
electrical connector in a manner to prohibit any
unintentional separation of a wire conductor from the
connector.
Another object is to provide a snap fit wire retainer
that extends inwardly of an electrical connector body
constructed so that the wire retainer is externally secured
to the exterior of the connector body so as to facilitate
the assembly of the associated wire retainer within the
inlet end of a connector body.
Another object is to provide an electrical connector
assembly having a wire retainer arranged to be externally
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secured to the connector body in a fixed relationship
relative to the connector body so that the free end thereof
extends into the inlet end portion of the connector body so
that a wire conductor may be unidirectionally snap fitted
thereto.
The foregoing objects and other features and
advantages are attained by an electrical connector assembly
that includes a connector body having an inlet end portion
for receiving an electrical conductor and an outlet portion
which is adapted to be inserted through a knockout hole of
an electrical panel or electric box, e.g. an electric
outlet box or the like. A radially outwardly extending
flange circumscribes an intermediate portion of the
connector body to function as a stop to limit the insertion
of the outlet end portion of the connector body through the
knockout hole of an electric box. The outlet end portion
may be provided with an outer surface that converges or
tapers inwardly toward the outlet opening thereof. Formed
on the surface of the outlet end portion are one or more
retaining lugs, which may be circumferentially spaced about
the outlet end portion. A frustro-conically shaped snap-
fit ring is fitted onto the outlet end portion.
In accordance with this invention, the outer retaining
ring is initially formed from a blank of sheet metallic
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material, e.g. spring steel, having a cruciform shape that
includes a face portion with a central opening wherein the
radiating arms of the cruciform blank are disposed about
the face portion to define a frustro-conical ring or cup.
The ring so formed is provided with blanked out or die cut
tangs to define locking tangs and grounding tangs. The
frustro-conical ring so formed also has a slot adapted to
receive the retaining lug when the retaining ring is fitted
onto the outlet end portion of the connector body so that
the free or trailing ends of the ring define grounding
tangs that engage the inner periphery of the knockout hole
of an electric box for effecting positive electrical
continuity or electrical grounding.
To form the retaining ring, the cruciform arms are
arranged to be folded relative to the front or face forming
portion of the blank, which is provided with a central
opening, to define a unitary frustro-conically shaped cup-
like member to compliment or be fitted onto the outlet end
portion of the connector body. The retaining ring thus
formed is fitted over or onto the outlet end portion
whereby the retaining slot formed in the ring is adapted to
receive the complementary retaining lug formed on the
surface of the outlet end portion for retaining the ring on
the outlet end portion of the connector body. In one form
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of the invention, as will be described herein, the retainer
ring is provided with an enlarged slot, i.e. the slot has a
width which is greater than the width of the lug to be
received therein.
In another form of the invention, the outer retaining
ring is initially formed from a blank of sheet metallic
material, e.g. spring steel which is generally circular in
shape and from which a pair of spaced locking tangs are
blanked, formed or die cut, out of the plane of the blank.
The portion of the blank extending between the opposed '
locking tangs define the opposed grounding tangs. The
arrangement is such that the grounding tangs encompass
almost the entire trailing end of the retaining ring, so as
to maximize the electrical grounding effect between the
electrical connector provided with such snap fit retaining
ring and a metallic electrical box or panel to which the
electrical connector assembly is secured.
With the construction described, the connector
assembly can be readily inserted through the knockout
opening of an electric box wherein the locking tangs will
initially be flexed inwardly to pass through the knock-out
hole of an electric box, and then spring outwardly to lock
the connector assembly to the electric box with the
grounding tangs or free ends of the retaining ring or arms
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being inherently biased or urged against the internal
periphery of the knockout hole of an electric box or panel
to effect a positive electric ground therebetween, due to
the inherent resiliency of the respective grounding tangs
and the material from which they are formed.
Because the locking tangs are formed of spring steel
and are relatively short, considerable force is required to
flex the locking tangs inwardly to overcome the inherent
spring bias of the locking tangs sufficiently to push the
connector assembly through the opening or knockout hole of
an electric box. When such electric box is concealed
within a wall, considerable difficulty has been encountered
in attaching a connector assembly provided with a "snap
fit" retainer ring to such electric box. In such
situations, electric connectors having a threaded outlet
end have been generally used, whereby such threaded
connectors could be readily secured by a lock nut from
within the electric box.
This invention further contemplates providing a tool
that will engage an enlarged slot of a modified frustro-
conical retainer ring embodiment of this invention whereby
the tool functions as a lever to transmit the necessary
pulling force on the modified connector assembly to pull
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the "snap ring" connector assembly through the knockout
opening of an electrical box with a minimum of ease.
This invention further contemplates providing the
inlet end of the connector with an inner or internal
conductor retainer ring which is uniquely formed for
positively securing thereto a wire conductor by merely
inserting the wire conductor into the inner retainer ring,
so that the wire conductor is prohibited from being
unintentionally separated therefrom. The inner retainer
ring is preferably formed of a blank of spring metal
material which is rolled to form a cylinder or sleeve
having an outer diameter which can be frictionally retained
within the inlet end of a connector, e.g. by a press or
friction fit.
A further embodiment of the disclosed invention
utilizes a simplified clamping arrangement for securing the
wire conductor to the inlet end of the connector by a mere
insertion. In the event the wire conductor has a helical
wound armored shield, e.g. a BX wire conductor, such
armored wire conductor may be alternatively secured to the
wire retainer ring or sleeve by threading the armored
conductor to the wire retainer ring or sleeve.
A further embodiment of the invention utilizes a
connector body having complementary housing or body
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sections which can be mated together and secured by a
fastener. One of the body sections is formed wih a leading
end that is provided with an outer frustro conical surface
and a trailing end having multiple chambers interconnected
to the leading end by a transition section. The other body
section defines a trailing end complementing the trailing
end portion of the other housing section. An outer frustro
conical retainer ring circumscribes the leading end of the
connector body to provide a snap fit connection for the
connector assembly to a knockout hole of an electric box.
The respective chambers, defined by the mated complementary
trailing ends of the connector, are each fitted with a
spring steel retainer sleeve to provide a snap fit
connection between a wire conductor and its corresponding
inlet end of the assembled connector body section. The
arrangement is such that each of the respective wire
retainers is securely clamped between the respective body
sections to provide a very positive surface to surface
contact between the wire retainer and the associated body
sections to enhance the electrical continuity between the
assembled connector body sections and the wire retainer
clamped therebetween.
A still further embodiment of the invention utilizes a
modified connector body provided with a frustro conical
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outlet end having a frustro conical shaped external snap
fit retaining ring by which the connector assembly can be
readily attached to an electrical panel or electrical box
by a snap fit, and having a uniquely formed wire retainer
device that clips onto the inlet end of the connector
body and is externally secured to the connector body for
enhancing ease of assembly while providing the wire
retainer to extend into the inlet end of the connector
body with sufficient flexibility and range of movement
for retaining a wire conductor or conductor sheath
within the connector body in a manner to prohibit any
Unintentional separation of the wire conductor or sheath
from the connector body.
In another embodiment of the present invention there
is provided an electric connector assembly comprising: a
connector body having an inlet end portion, and an outlet
end portion, said outlet end portion defining an outlet
opening, a radially outward extending stop flange formed
about an intermediate portion of said connector body, and
a snap fit retaining ring having a leading end and a
trailing end, and having a frustro-conical configuration
wherein the diameter of the trailing end of said frustro-
conical configuration is greater than the diameter of
said leading end thereof, said frustro-conical retaining
ring having at least one locking tang and grounding tang
formed out of the surface of said retaining ring the
grounding tang including a free end defining a
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curvilinear contact area that extends over at least 270
of the circumference of the leading end, and means for
securing said retaining ring onto said outlet end portion
of said connector body.
In a further embodiment of the present invention
there is provided an electrical connector assembly
comprising: a connector body having an inlet end
portion, and an outlet end portion, said outlet end
portion defining an outlet opening, a radially outward
extending stop flange formed about an intermediate
portion of said connector body, and a snap fit retaining
ring having a leading end and a trailing end, and having
a frustro-conical configuration wherein the diameter of
the trailing end of said frustro-conical configuration is
greater than the diameter of said leading end thereof,
said frustro-conical retaining ring having at least one
locking tang and grounding tang formed out of the surface
of said retaining ring the grounding tang including a
free end defining a curvilinear contact area that extends
over at least 270 of the circumference of the leading
end, and means for securing said retaining ring onto said
outlet end portion of said connector body, wherein said
grounding tang includes a free end defining a curvilinear
contact area that extends about the entire circumference
of said trailing end.
In another embodiment of the present invention there
is provided an electrical assembly comprising: an
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electrical panel having a knock-out hole and an
electrical connector assembly adapted to be secured to
said knock-out hole, said connector assembly including a
connector body having an inlet end, an outlet end and a
bore connecting said inlet end to said outlet end, a
radially outwardly extending stop flange circumscribing
said connector body between said inlet and outlet end,
said outlet end defining an outlet opening, and said
outlet end having an outer sloping surface between said
stop flange and said outlet opening, that slopes
downwardly toward said outlet opening, a snap fit
retaining ring having a leading end and a trailing end
defining a frustro-conical surface therebetween wherein
the diameter of said trailing end is greater than the
diameter of said leading end, means for securing said
retaining ring on said outer sloping surface of said
outlet end, a pair of opposed locking tangs formed out of
said frustro-conical surface, said pair of opposed
locking tangs being outwardly bent at an angle relative
to the surface of said frustro-conical surface, and the
remainder of said frustro-conical surface between said
leading end and trailing end forming a grounding tang for
effecting an electrical grounding effect between said
connector assembly and said electrical panel when said
connector assembly is secured to said knock-out hole of
said electrical panel the grounding tang engaging at
least 270 of the inner periphery of the knock-out hole.
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In a further embodiment of the present invention
there is provided an electrical assembly comprising: an
electrical panel having a knock-out hole and an
electrical connector assembly adapted to be secured to
said knock-out hole, said connector assembly including a
connector body having an inlet end, an outlet end and a
bore connecting said inlet end to said outlet end, a
radially outwardly extending stop flange circumscribing
said connector body between said inlet and outlet end,
said outlet end defining an outlet opening, and said
outlet end having an outer sloping surface between said
stop flange and said outlet opening, that slopes
downwardly toward said outlet opening, a snap fit
retaining ring having a leading end and a trailing end
defining a frustro-conical surface therebetween wherein
the diameter of said trailing end is greater than the
diameter of said leading end, means for securing said
retaining ring on said outer sloping surface of said
outlet end, a pair of opposed locking tangs formed out of
said frustro-conical surface, said pair of opposed
locking tangs being outwardly bent at an angle relative
to the surface of said frustro-conical surface, and the
remainder of said frustro-conical surface between said
leading end and trailing end forming a grounding tang for
effecting an electrical grounding effect between said
connector assembly and said electrical panel when said
connector assembly is secured to said knock-out hole of
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said electrical panel the grounding tang engaging at
least 270 of the inner periphery of the knock-out hole,
wherein said knock-out hole is circular, wherein said
grounding tang includes said trailing end of said
retaining ring arranged to engage the entire inner
periphery of said knock-out hole when said connector
assembly is secured in said knock-out hole.
In another embodiment of the present invention there
is provided an electrical assembly comprising: an
electric box having a knock-out hole and an electrical
connector assembly, said electrical connector assembly
including a connector body having an outlet end portion
and an inlet end portion whereby said outlet end portion
is adapted to be received within said knock-out hole,
said outlet end portion defining an outlet opening, a
snap fit retaining ring having a leading end, a trailing
end and an outer sloping surface therebetween defining a
frustro-conical configuration wherein said trailing end
has a diameter greater than that of said leading end,
means for securing said snap fit retaining ring on said
outlet end portion, a pair of locking tangs formed out of
said surface of said retaining ring, said locking tangs
being outwardly bent at an angle greater than said
sloping surface of said retaining ring, and said sloping
surface of said retaining ring extending between said
locking tangs defining a grounding tang that includes a
circumferential portion of said trailing end that extends
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through at least an arcuate portion thereof ranging
between 270' to 360.
TRE DRAWINGS
Fig. 1 is an exploded perspective view of the
electrical connector assembly.
Fig. 2 is a plan view of the blank from which the
outer retaining ring of the present invention is forwed.
Fig. 3 is a detail front view of the outer retainer
ring.
Fig. 4 is a detail top plan view of the outer
retainer ring.
Fig. 5 is a detail end view of Fig. 4.
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Fig. 6 is a sectional view of the outer retainer ring
taken along line 6-6 on Fig. 3.
Fig. 7 is a side view of the connector assembly
illustrating the alignment thereof relative to the knockout
opening of an electric box.
Fig. 8 is a section side view illustrating the
connector assembly secured to an electric box, taken along
line 8-8 on Fig. 10.
Fig. 9 is a sectional side view taken along line 9-9
on Fig. 10 and rotated 90 .
Fig. 10 is a fragmentary front view of the connector
assembly secured to an electric box as viewed from the
inside of the electrical box.
Fig. 11 is an exploded perspective view of a modified
form of the invention.
Fig. 12 is a sectional side view of the modified form
of the invention of Fig. 11.
Fig. 13 is a top plan view of the blank from which the
internal wire conductor retainer is formed.
Fig. 14 is a fragmentary top view of a portion of the
blank forming the inner retainer sleeve or ring.
Fig. 15 is an end view of the inner wire conductor
retainer ring or sleeve.
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Fig. 16 is a top view of the inner retainer ring or
sleeve of Fig. 15.
Fig. 17 is a section view taken along 17-17 on Fig.
16.
Fig. 18 is a side view of the inner retainer ring or
sleeve.
Fig. 19 is a sectional side view of still another
embodiment.
Fig. 20 is a perspective view of a further embodiment
of the invention.
Fig. 21 is an exploded perspective view of the
embodiment of Fig. 20.
Fig. 22 is a top plan view of the embodiment of Fig.
20 having parts thereof broken away.
Fig. 23 is a sectional view taken along line 23-23 on
Fig. 22.
Fig. 24 is the interior plan view of one section of
the connector housing of the embodiment illustrated in Fig.
20.
Fig. 25 is an outer end view of Fig. 24.
Fig. 26 is an end view of the connector housing
section of Fig. 24.
Fig. 27 is a sectional view of the housing section
taken along line 27-27 on Fig. 26.
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Fig. 28 is an inside plan view of the complementary
housing section of the embodiment illustrated by Fig. 20.
Fig. 29 is an end view of Fig. 28.
Fig. 30 is an inlet end view of Fig. 28.
Fig. 31 is a sectional view taken on line 31-31 on
Fig. 30.
Fig. 32 is a sectional view taken on line 32-32 on
Fig. 28.
Fig. 33 is a perspective exploded view of a further
embodiment of the invention.
Fig. 34 is a top plan view of the blank from which the
wire retainer device is formed.
Fig. 35 is a side view of the blank of Fig. 34.
Fig. 36 is a side view of the blank of Figs. 34 and 35
as formed to define wire retainer.
Fig. 37 is a top view of a slightly modified form of a
wire retainer.
Fig. 38 is a perspective view of the connector body
embodying the invention.
Fig. 39 is a side view of Fig. 38.
Fig. 40 is a top plan view of Fig. 39.
Fig. 41 is a left end view of Fig. 38.
Fig. 42 is a right end view of Fig. 38.
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Fig. 43 is a perspective view of the assembled
connector embodiment shown in Fig. 33.
Fig. 44 is a side sectional view of the connector
assembly of Fig. 43.
Fig. 45 is an exploded perspective of another modified
form of the invention.
Fig. 46 is a perspective view similar to Fig. 45
illustrated in the assembled position.
Fig. 47 is a side view of Fig. 46.
Fig. 48 is a side view of the connector assembly of
Fig. 47 in engagement with a pulling tool of the present
invention.
Fig. 49 is a bottom plan view of Fig. 48.
Fig. 50 is a side elevation view illustrating the
initial insertion of the connector assembly of Fig. 45 into
a knockout hole of an electric box.
Fig. 51 is a side elevation view similar to Fig. 50
illustrating the connector assembly fully seated and locked
in the knockout hole of an electric box which is affected
by the lever action of the operating tool.
Fig. 52 is a perspective view of the operating tool
embodiment for facilitating the locking of an electrical
connector to an electric box.
Fig. 53 is a plan view of the tool of Fig. 52.
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CA 02622237 2008-02-26
Fig. 54 is an edge view of Fig. 53.
Fig. 55 is a bottom plan view of Fig. 54.
Fig. 56 is a left end view of Fig. 55.
Fig. 57 is a perspective view of a slightly modified
tool.
Fig. 58 is a left end view of Fig. 57.
Fig. 59 is a perspective view of still another
modified operating tool.
Fig. 60 is an exploded perspective view of another
form of the invention embodying a modified frustro-conical
retaining ring for enhancing the electrical grounding
effect.
Fig. 61 is a plan view of the blank from which the
modified frustro-conical retaining ring of Fig. 60 is
formed.
Fig. 62 is a detail front view of the retainer ring
formed from the blank of Fig. 61.
Fig. 63 is a detail top plan view of Fig. 62.
Fig. 64 is a detail left end view of the retainer ring
of Fig. 63.
Fig. 65 is a sectional side view of the electrical
connector assembly of Fig. 60 connected to an electric box.
Fig. 66 is a section view taken along line 66-66 taken
on Fig. 65.
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Fig. 67 is a perspective exploded view illustrating
the connector assembly of Fig. 60 in alignment relative to
a knock-out hole of an electric box.
Fig. 68 is a plan view of a modified blank from which
another modified frustro-conical retaining ring is formed.
Fig. 69 is a front elevation view of the formed
modified frustro-conical retaining ring.
Fig. 70 is a top view of Fig. 69.
Fig. 71 is a left side view of Fig. 70.
Fig. 72 is a sectional view of an electrical connector
assembly with the modified frustro-conical retainer of Fig.
69 secured to an electrical box or panel.
DETAILED DESCRIPTION
Referring to the drawings, there is shown in Fig. 1 an
electrical connector assembly 10. The connector assembly
includes a connector body 11, which is usually formed of
metal casting, e.g. zinc or other suitable metallic alloy.
The connector body 11 is formed with an inlet end portion
11A and an outlet end portion 11B and having a bore 12
extending therethrough. Intermediate the connector body 11
or between the inlet end portion 11A and outlet end portion
11B there is provided a radially outwardly extending flange
13 which functions as a stop to limit the amount that the
24
CA 02622237 2008-02-26
connector body 11 may be inserted through the knockout hole
14 of an electric box 15, as noted in Fig. 8.
As shown in Figs. 1 and 8, the outer surface S of the
outlet end portion 11B slopes, tapers or converges toward
the outlet opening 16 whereby the outer surface S of the
outlet end portion 11B has a generally frustro-conical
configuration. Formed on the surface S of the outlet end
portion 11B is an outwardly projecting retainer lug 17. In
the illustrated embodiment, two such lugs 17 are shown
disposed 1800 apart about the outer circumference of the
outlet end portion 11B.
The connector assembly 10 also includes a snap fit
retaining ring 18. In accordance with this invention, the
retaining ring 18 is integrally formed from a blank 19 of
spring steel material. As best seen in Fig. 2, the blank
19 is initially formed or stamped to define a generally
cruciform shape. The cruciform shape is provided with a
face portion 20 having central opening or hole 20A and
having four generally radially extending arms defining two
pairs of oppositely disposed arms AA and BB.
As illustrated in Fig. 2, the opposed pair of arms AA
are each provided with a retaining slot 21. The opposed
pair of arms BB, as best seen in Fig. 8, are blanked or
formed to define a locking tang 22 and to either side
CA 02622237 2008-02-26
thereof an electrical grounding tang 23, 23. As hown, the
locking tang 22 is slightly shorter than the adjacent
grounding tangs 23, 23. The arrangement is such that the
free end of the locking tangs 22 are formed so as to engage
the inside surface of the electric box 15 in the assembled
portion, as best seen in Fig. 9, to secure the connector
assembly 10 to the electric box 15 and prohibit any
unintentional withdrawal of the connector assembly 10 from
the electrical box 15, whereas the free ends of the
grounding tangs 23 are biased in engagement with the
internal periphery of the knockout hole 14. Also, the free
ends 24, 24 of arms A, A in the assembled position will
also function as electrical grounding tangs, as noted in
Fig. 8.
In forming the retaining ring 18 from blank 19, the
respective arms A,A and B,B are subjected to a series of
progressive bending dies which will gradually bend the
respective arms about a foldline f, which defines the face
or front portion 20, whereby arms A,A and B,B form a cup
having circumscribing frustro-conical or outwardly flaring
sides to define a frustro conical ring 18 which complements
the conical surface S of the leading or outlet end portion
11B, as seen in Fig. 1. In doing so, the locking tangs 22
are outwardly and cantileverly bent or displaced relative
26
CA 02622237 2008-02-26
to the surface of the ring at a slightly greater outwardly
angle or slope than the adjacent grounding tangs 23 and the
slope of arms A,A. With the retaining ring 18 so formed,
it can be readily fitted onto the outlet end portion 113
whereby the inherent resiliency of the arms A,A will cause
the retainer slots 22 to snap fit onto the retaining lug 17
when slots 21 are placed in alignment with lugs 17. The
arrangement is such that the retainer ring 18 will be
firmly and positively secured to the outlet end portion 11B
as seen in Fig. 8. Yet, due to the inherent resiliency of
the material of the retaining ring 18, it can be easily
detached from the outlet end portion 11B when removal is
desired, without destroying the ring 18 by lifting arms A,A
free of the retaining lugs 17.
With the retainer ring 18 properly secured to the
outlet end 113 of the connector body 11, the connector
assembly 10 can be readily secured to an electric box 10 by
simply aligning the assembly 10 with a knockout hole 14, as
best seen in Fig. 7, and inserting the leading or outlet
end portion into the knockout hole 14 until the flange 13
engages the outer side of the electric box 15. In doing
so, the tangs 22, 23 and the free ends 24 of arms A,A,
respectively, will depress inwardly to permit insertion of
the assembly 10. When the assembly is fully seated in the
27
CA 02622237 2008-02-26
knockout hole 14, the locking tangs 22 will normally spring
outwardly to secure the assembly 10 to the electric box 15,
as noted in Fig. 9. The inherent resiliency of the
grounding tangs 23, 23 and the free end 24 of arms A,A are
normally biased in engagement with the internal periphery
of the knockout hole 14 to ensure a positive electrical
ground with the electric box 15. The engagement of the
free ends 24 of arms A,A against the inner periphery of the
knockout hole 14, as noted in Fig. 8, further ensures the
firm securing of the retaining slot 21 with the retaining
lugs 17, so as to prohibit any disengagement of the outer
retaining ring 18 from the connector body 11.
It will be understood that the wire conductor 25 may
be secured to the connector assembly 10 either before or
after the assembly 10 has been secured to the electric box
15. In the illustrated embodiment, the conductor wire 25
is simply inserted into the inlet end portion 11A and
secured in position by a suitable securing means. In the
illustrated embodiment of Fig. 1, the securing means is
illustrated as a set screw 26. However, it will be
understood that other forms of securing means may be used,
than the set screw 26 illustrated.
From the foregoing, it will be apparent that the
disclosed connector assembly is quite novel and simple in
28
CA 02622237 2008-02-26
construction. The snap fit retaining ring 18 can be simply
formed from a cruciform shaped blank 19 whereby the opposed
radially extending arms A,A and B,B can be readily formed
into a cup having a generally frustro-conically shaped
sidewalls complementing the slope of the outlet end portion
11A, and whereby the outer retainer ring 18 can be readily
secured to the connector body simply by the inter-
engagement of slots 21 with its complementary lugs 17.
In the assembled position, the outer retainer ring 18
is positively secured to the connector body in a manner to
prohibit any unintentional separation. Also the tangs 22
and 23, which are formed integral with ring 18, are shaped
and formed so that the locking tangs 22 secure the assembly
to an electric box 15 while the grounding tangs 23
ensure a positive electrical ground of the assembly 10 with
the associated electric box 15.
Fig. 11 illustrates a perspective view of a modified
form of the invention. As illustrated in Fig. 11, the
connector assembly 30 includes a connector body 31 which
may be formed as a casting form of a suitable metal or
alloy, e.g. zinc and the like, as hereinbefore described.
The connector body 31 includes a conically shaped outlet
end 31A similar to that described with respect to Fig. 1,
and a cylindrical inlet end 315. A circumscribing internal
29
CA 02622237 2008-02-26
shoulder 31C is formed intermediate the opposed ends of the
connector body 31. As shown in Fig. 12, the internal
shoulder 310 defines the demarcation between the bore 32A
defining the outlet end 31 and the bore 32B defining the
bore of the inlet end. Circumscribing the connector body
31 about the exterior thereof is a radially outwardly
extending stop flange 33.
The outlet end 31A of the connector body 30 is
provided with opposed retaining lugs 37 adjacent the outlet
opening 36. Circumscribing the sloping or conical surface
S of the outlet end 31A is the outer retaining ring 38,
similar to that hereinbefore described with respect to
Figs. 1 to 10.
In the embodiment illustrated in Fig. 11, the
connector assembly 30 includes an internal wire retainer 39
in the form of a ring, cylinder or sleeve which is fitted
to the bore 32B of the connector body 31, and which
retainer 39 functions as a unidirectional retainer means
arranged to permit a wire conductor to be readily inserted
and secured thereinto, and which will resist any applied
force imparted to the wire conductor in the opposite
direction to prohibit any unintentional separation of the
wire conductor from the connector body 31. Wire conductor,
as used herein, means any wire, cable, helical wound metal
CA 02622237 2008-02-26
,
covering or sheath (BX) wire, plastic sheath wire conductor
and the like.
Referring to Figs. 13 to 15, the internal retainer 39
is preferably formed from an elongated blank 40 of spring
steel. The retainer blank 40, as best seen in Fig. 13,
comprises an elongated generally rectangular blank having a
longitudinal leading edge 40A, a trailing edge 40B and
opposed end edges 40C and 40D. End edge 40C is provided
with a pair of spaced apart notches 41, 41 and a projecting
tongue 42. The other end edge 40D of blank 40 is provided
with a pair of projecting tongues 43, 43 arranged to
complement notches 41, 41 and a complementary notch 44 for
receiving tongue 42 in the formed or rolled position of the
retainer sleeve 39, as shown in Fig. 18.
Blanked, lanced, cut or stamped out of the plane of
blank 40 are one or more tangs 45. In the form of the
invention as shown in Fig. 13, tangs 45 are formed out of
the plane of the blank. The respective tangs 45 are
bifurcated to define a pair of finger tangs 45A, 45A
longitudinally spaced along the longitudinal axis of the
blank 40 at a distance, which, when the blank 40 is rolled
to form the retainer sleeve 39, the respective pairs of
finger tangs 45A are oppositely disposed, as best seen in
Fig. 15.
31
CA 02622237 2008-02-26
As shown in Figs. 15 and 18, the respective finger
tangs 45A, 45A are inwardly bent out of the plane of the
retainer sleeve 39. In the illustrated embodiment, the
respective finger tangs are provided with a pair of
intermediate transverse fold lines F1 and F2 whereby the free
end of the respective finger tangs is directed toward the
longitudinal axis of the sleeve 39, as shown in Fig. 18.
Referring to Fig. 15, it will be noted that the
retainer sleeve is provided with a flattened portion 46 on
one side thereof.
The connector body of Figs. 11 and 12 may be formed
with an internal complementary flat surface along a portion
of the inner circumference thereof. The arrangement is
such that the retainer sleeve 39, when inserted into the
inlet end 31B of the connector body, is oriented so that
the flattened surface 46 of the sleeve 39 complements the
internal flattened surface 47 of the connector body. The
orientation is such that the opposed finger tangs 45A are
oppositely disposed to firmly grip the wire conductors,
e.g. an armored conductor or other covered conductor.
The outer circumference of the inner retainer sleeve
or ring 39 is proportioned so that it can be press fitted
or frictionally fitted into the inlet end 31B of the
connector body 31 by a force sufficient to firmly secure
32
CA 02622237 2008-02-26
the inner retainer ring or sleeve 39 within the inlet end
so as to prohibit any separation of the retainer ring or
sleeve 39 from the inlet end of the connector body. The
complementary flattened surfaces 46 of the internal sleeve
39 and 47 of the inlet end of the connector body insures
proper orientation of the internal sleeve 39 within the
inlet end of the connector body.
Fig. 14 illustrates a fragmentary portion of the blank
40 to show an intermediate step in forming the tang fingers
45A, 45A so that when the formed blank 40 is rolled to form
the internal retaining sleeve, the tang fingers will be
disposed in parallel as seen in Figs. 15 and 16. This is
attained by fold line F3 which is disposed at an angle, as
noted in Fig. 14, so that when the blank is rolled to form
the internal retaining sleeve 39, the tang fingers 45A, 45A
will be disposed in parallel. The free ends 45B of the
respective fingers 45A are angularly offset to engage the
grooves of an armored conductor, as noted in Fig. 12 or
other covering sheath of a wire conductor that will resist
a force attempting to effect separation of the conductor
from the connector assembly. The respective free ends 45B
may also be laterally offset so that an armored conductor
may be threadedly connected to the internal sleeve 39, as
33
CA 02622237 2008-02-26
well as by simply inserting the armored covered conductor
into the retainer sleeve to effect a snap fit connection.
Fig. 19 illustrates a further embodiment of the
invention. The embodiment of Fig. 19 is directed to a
connector assembly 50 which is generally similar to that
disclosed in Figs. 1 to 10. The embodiment of Fig. 19
differs from that disclosed in Figs. 1 to 10 and Figs. 11
to 18 in that the connector body 51 is provided with a
slotted opening 52 in the inlet end 51A thereof positioned
adjacent to the radially outwardly extending flange 53.
Intermediate between the inlet end 51A and the flange 53,
the inlet end is provided with a tapped or threaded hole 54
for receiving a set screw 55.
In this form of the invention, the wire retainer means
comprises an inverted U shape clamp 56 having opposed leg
portions 56A, 56B and an interconnected web 560. The web
56C is provided with an aperture or hole 57 arranged to be
disposed in alignment with the tapped or threaded hole 54.
The web 56C is sufficiently wide so that one leg, e.g. leg
563, is extended through the slotted opening 52 and the
other leg 56A extends over the inlet opening 58 to the
inlet end portion 51A. The retaining clamp 56 is
adjustably secured to the connector body 51 by the set
screw 55 extending through hole 54 disposed in alignment
34
CA 02622237 2008-02-26
,
with screw hole 54. By having one leg 56B extending
through the slotted opening 52 and the other leg 56A
extending over the inlet opening 58, the clamp 56 can be
readily adjusted relative to the connector body by turning
the set screw 18 in one direction or the other. The
arrangement is such that as the set screw 55 is tightened,
the opposed and spaced apart free ends of the respective
clamp legs 56A, 56B will exert a bearing force on the wire
conductor sheath to positively secure a wire conductor to
the inlet end of the connector assembly. In all other
respects, the connector assembly of Fig. 19 is similar to
that disclosed in Figs. 1 to 10, and need not be repeated.
Figs. 20 to 32 are directed to a further modification
of the disclosed invention. As best seen in Figs. 20 and
21, the connector assembly 60 includes a housing or
connector body formed of a pair of complementary sections
or members 61 and 62. The respective complementary
sections or members 61 and 62 are preferably formed as
casting of any suitable metal or alloy material, e.g. zinc,
aluminum and the like.
As best seen in Fig. 21, one of the housing
complementary members, e.g. 61, is provided with a
projecting leading or outlet end 61A, which is adapted to
be inserted through a knockout hole 14 of an electric box
CA 02622237 2008-02-26
,
or panel 15. The leading or outlet end 61A is formed with
an annular configuration to define an outlet opening 63,
through which the conductor leads or wires 80A may extend
as noted in Fig. 20. The outer surface S of the leading
end 61A slopes or tapers downward toward the central axis
of the connector assembly to define a frustro conical outer
surface S on the leading end 61A.
The complementary member 61 also includes a trailing
or inlet end 64. As shown in Fig. 21, the trailing or
inlet end 64 is formed as a pair of semi-cylindrical
chambers 64A, 64B disposed in parallel side by side
arrangement separated by an intermediate wall or division
65. The opposed ends of the respective chambers 64A, 64B
are defined between an inturned lip 66A circumscribing the
inlet opening 66 to the respective chambers 64A, 64B and a
transverse web 67. A transition section 68 connects the
respective chambers 64A-64B to leading or outlet end 61A.
Extending through the intermediate wall 65 is a tapped
hole 68B having internal threads. Also formed on the wall
65 is an aligning depression or recess 69. Circumscribing
the leading or outlet end61A is a radially outwardly
extending flange 70 which functions as a stop to limit the
distance the connector assembly 60 can be inserted through
a knockout opening 14 of an electric box or panel 15.
36
CA 02622237 2008-02-26
The complementary housing section or member 62 is
formed with a pair of semi-cylindrical chambers 64A', 648'
disposed in parallel relationship and arranged to
complement chambers 64A, 64B in the assembled position of
the respective housing members 61, 62, as best noted in
Figs. 20 and 31. Housing member 62 is provided with a hole
71 extending therethrough which is arranged to be disposed
in alignment with the tapped hole 68B whereby the
respective housing sections 61, 62 can be secured in the
assembled position by a threaded fastening screw 72
inserted through hole 71 and threaded into the tapped hole
68 of the other housing member 61. Housing member 62 is
also provided with a transition section 68A that
complements transition section 68 of the other housing
member or section 61.
To facilitate the alignment of the two housing
sections 61 and 62 in assembling the sections 61, 62, there
are provided complementary aligning means. In the
illustrated embodiment, the aligning means comprises a
notch 73 formed at the leading end of the housing member 62
which is arranged to mate with a complementary projection
or lug 74 formed on the outlet end portion of the housing
member 61. Another alignment means includes a recess or
depression 69 formed in the dividing wall 65 of housing
37
CA 02622237 2008-02-26
member 61 arranged to be disposed in alignment with the
projection or dimple 69A formed on the dividing wall 65A of
housing member 62.
In this form of the invention, the outlet or leading
end 61A is provided with retainer lug 75 projecting
outwardly from the conical surface S of the outlet end 61A.
In the illustrated embodiment, two such retaining lugs 75
are oppositely disposed. Disposed about the outer sloping
or tapered surface S of the outlet end 61A is a frustro-
conical retainer ring 76. The conical retaining ring 76 is
formed and constructed in the manner hereinbefore described
with respect to Figs. 2 to 4 and need not be repeated. As
seen in Figs. 20 and 21, the frustro conical external
retainer ring 76 can be readily slipped onto the outlet end
61A so that upon engagement of the retainer lugs 75 with
the complementary slots 76A formed on the retainer ring 76,
the retainer ring 76 is maintained in position on the
external surface S of the leading or outlet end 61A as
hereinbefore described.
In this form of the invention, a wire conductor
retainer ring or sleeve 77 is arranged to be disposed and
clamped between the complementary chambers defined by the
respective housing sections or members 61, 62 when
assembled. The respective wire retainer rings or sleeves
38
CA 02622237 2008-02-26
77 are similar in construction and function to that
described with respect to Figs. 13 to 16, which need not be
repeated. It will be noted that dividing wall 65, 65A of
the respective housing members 61, 62 are arranged to
engage the flat area 77A of the respective wire retainer
sleeves 77 thereby functioning as a means for effecting
proper orientation of the respective wire retainer sleeves
77 within their respective chambers in the assembled
position of the housing sections or members 61, 62.
To assemble the connector 60 of Figs. 20, 21, a formed
conductor wire retainer ring 77 as hereinbefore described,
is position in each semi-cylindrical chamber defined in one
of the housing sections, e.g., as illustrated in Figs. 21
or 22; noting that the flat portion 77A of the respective
wire conductor retainer sleeves 77 are positioned against
the adjacent opposing surfaces 653 of the dividing wall 65,
as best seen in Fig. 23. In this position, the opposite
ends of the respective sleeves 77 abut the interior lip 66A
adjacent the inlet opening and the transverse web 67. With
the wire retainer rings 77 thus positioned within their
respective chamber, the other housing member, e.g. member
62, is fitted to housing member 61 whereby the respective
housing sections clamp the respective wire retaining
sleeves 77 therebetween as the fastening screw 72 is
39
CA 02622237 2008-02-26
rotated to secure the two housing sections together as
shown in Figs. 20 and 23. It will be noted that the outer
diameter (OD) of the wire retainer sleeves 77 are
substantially equal to or slightly greater than the
internal diameter of the respective chambers in the
assembly position of the housing sections 61, 62, as noted
in Figs. 20 and 23. The arrangement is such that the
respective retainer sleeves 77 are firmly secured within
their respective chamber, when assembled, so that the wire
retainer sleeves are prohibited from being separated from
the connector body or housing. With the housing members
61, 62 thus secured, the external retainer ring 76 can be
readily fitted onto the leading end 61A of the connector
body or housing, as hereinbefore described.
With the connector body of Fig. 20 thus assembled, it
will be noted that the connector assembly 60 can be readily
secured to an electric box or panel simply by inserting the
leading or outlet end 61A through a knockout hole of a
panel or electrical box so as to be readily secured thereto
with a snap fit as hereinbefore described. Also with the
arrangement described, a wire conductor or cable can be
readily attached to the trailing end of the connector
assembly 60 with a simple snap fit.
=
CA 02622237 2008-02-26
Fig. 20 illustrates a wire conductor having an
external helically wound sheath or outer covering 80 which
can be readily inserted through the inlet opening of one of
the respective chambers formed in the trailing end whereby
the gripping tangs 78 formed in the wire retainer sleeves
77, as hereinbefore described, securely grips the armored
cable or wire conductors with a snap fit, the arrangement
being such that the wire so secured is prohibited from
becoming accidentally separated from the connector body, as
hereinbefore described. While a conventional armored type
conductor 80 is illustrated in Fig. 20, it will be
understood that the described connector assembly herein can
be suitable for use with other types of wire conductors,
e.g. conductors having an external plastic or fabric like
sheath.
By simply removing the single fastening 72, the entire
assembly can be readily taken apart to effect the
separation of the wire conductor if so desired. If
desired, the transition portions 68, 68A of the respective
housing sections 61, 62 may be provided with peep holes 70
to view the individual conductor wires 80A arranged within
the connector body to facilitate an electrical
installation.
41
CA 02622237 2008-02-26
From the foregoing, it will be noted that the
connector assemblies disclosed herein utilize a frustro
conically shaped outer retainer ring which is uniquely
secured to the leading end of a connector body, with
securing tangs and grounding tangs arranged to effect both
a positive securement of the connector assembly to a
knockout hole of an electric box or panel and a positive
electrical ground. In association with an external frustro
conical retaining ring, other disclosed embodiments include
a trailing end constructed to receive one or more wire
conductors and retaining the same to the connector body
with a simple snap fit motion. While the embodiment of
Fig. 20 has been illustrated and described as having a
duplex trailing end portion, it will be understood that the
subject matter described can be utilized with one or more
chambers formed in the trailing end of the connector body
described herein, depending upon the number of wire
conductors one may wish to connect to a single connector
body.
With respect to the embodiment of Figs. 20 to 32, the
arrangement is such that the connector body, being formed
of two component housing sections, and secured together
with a fastener as described imparts a clamping force onto
the spring steel wire retaining ring or sleeve with a
42
CA 02622237 2008-02-26
surface to surface contact to enhance electrical
conductivity or grounding between the component housing
sections, and the wire retaining sleeves clamped
therebetween.
Figs. 33 to 44 illustrate a further modification of
the invention. In this embodiment, the connector assembly
80 includes a connector body 81, an outer frustro conical
external snap-fit retainer ring 82, a wire retainer device
83, and an optional plastic electrical insulating end ring
insert 84.
As shown, the connector body 81 includes an inlet
portion 81A and an outlet portion 81B, formed as a casting
of a suitable metal, e.g. zinc or other suitable metal
alloy. The inlet portion 81A, for the greater portion
thereof, is defined by a cylindrical body having a
circumference which is greater than 180 , and preferably
about 320 plus or minus a few degrees. The open portion
of the cylindrical body defining the inlet end portion 81A,
as viewed in Figs. 33 and 43, is provided with a flat
closure 85 which is integrally connected to the opposed
edges of the cylindrical body by interconnecting opposed
side walls 85A and 85B. Projecting outwardly of the flat
closure 85 is an anchoring pin or boss 86.
43
CA 02622237 2008-02-26
The outlet portion 81B comprises a frustro conical end
similar to that hereinbefore described with respect to the
embodiments of Figs. 1, 11, 19 and 21. Also, the external
snap fit ring 82 adapted to be disposed about the outlet
end portion 81B is structurally and functionally similar to
that hereinbefore described, and need not be repeated.
In the embodiment of Figs. 33 and 44, a wire retainer
or device 83 is arranged to extend into the inlet portion
81A, whereby a wire conductor 90, adapted to be inserted
into the inlet portion 81A, is retained therein merely by
inserting the wire conductor into the inlet end portion
81A. The arrangement is such that the wire conductor 90,
once inserted into the inlet portion 81A and past the free
end 83C of the wire retainer 83, positively retains the
wire conductor 90 so as to prohibit any unintentional
separation of the wire conductor 90 from the connector body
81, as best seen in Fig. 44.
The wire or conductor retainer 83 is formed from an
elongated rectangular blank 87, preferably a blank of
spring steel. The blank 87 is provided with a plurality of
longitudinally spaced apart transverse foldlines F1 to F6,
whereby the blank 87 can be readily formed to define the
spring steel retainer 83.
44
CA 02622237 2008-02-26
As shown, the elongated blank 87, intermediate the
length thereof and adjacent the longitudinal edges 87A,
87B, is provided with die cut or slit 87C to form opposed
projecting prongs 88 that are bent out or project beyond
the plane of the blank 87. The right end of the blank 81,
as seen in Fig. 35, is reversely bent or folded about
foldlines F1 and F2 so as to overlie the projecting prongs
88, as best seen in Fig. 36, whereby the reversely bent end
83A is spaced above the projecting prongs 88. Formed in
the bent end 83A is an aperture or hole 89 which is
positioned to receive anchor pin or boss 86 in the
assembled position. The portion of the blank 87 to the
left of the prongs 88 are bent about transverse foldlines
F3, F4, F5 and F6 at longitudinally spaced intervals to
configure the blank 87 with a series of angular bends, as
shown in Fig. 36. The angle of respective bends about the
respective foldlines F3 to F6 is not critical and may vary
depending upon the internal diameter of the inlet end 81A.
As shown in Fig. 44, the retainer device 83 may be
angularly bent so that the free end 83B extends to a
position sufficient to engage the wire conductor or the
wire covering or sheath 90, as noted in Fig. 44.
In the illustrated embodiment, the wire conductor, as
shown, includes a typical helically wound metallic sheath
CA 02622237 2008-02-26
,
or covering 90 that houses the conducting insulated wires
90A. To facilitate the retention of the sheath 90, the
free end of the retainer device 83 may terminate in a
curvilinear arc 83B to complement the circumference of the
sheath 90 disposed between the adjacent helical ridges as
best seen in Fig. 44.
To assemble the wire retainer 83 to the inlet portion
81A of the connector body 81, the reversely bent end
portion is fitted to or clipped onto the end of the flat
closure or top 85, as best seen in Figs. 43 and 44 so that
the anchoring pin 86 is received in the hole 89. To secure
the retainer device 83 to the connector body 80, the top of
the anchor pin is swedged so as to deform the end of the
anchor pin 86, whereby the deformation of the anchor pin 86
firmly and fixedly secures the retainer device 83 to the
connector body. In the swedging operation, the prongs 88
formed in the blank 87 are caused to "bite" into the under
surface of the flat closure or top 85, as best seen in Fig.
44, to enhance the attachment of the retainer device 83 to
the connector body 81. To complete the assembly of the
connector assembly, the frustro conical external ring 82 is
snap fitted onto the conically formed outer end portion 81B
as hereinbefore described. While the means for securing
the wire retainer 83 to the connector body portion 81A is
46
CA 02622237 2008-02-26
described by means of a swedged pin, it will be understood
that other suitable fastening means may be used, e.g.
screws, bolts, welding, solder and the like.
As will be best noted in Fig. 44, the retainer device
is so formed that the free end 83B is arranged to extend
into the inlet portion 81A of the connector body 81 and is
angularly disposed so as to enable a wire conductor or
sheathing 90 to be unidirectionally inserted into the inlet
end portion 81A so as to be retained by the free end 83A of
the retaining device 83 in a manner whereby the wire
conductor 90 is prohibited from being unintentionally
separated from the connector body.
To effect the release of the wire conductor, one need
only to insert an appropriate tool to effect displacement
of the retainer device away form the wire conductor or
covering sheath 90, to effect the withdrawal of the
conductor sheath 90.
Fig. 37 illustrates a slightly modified wire retainer
device 91. The modified wire retainer device 91 is similar
to that the wire retainer 83, herein described, with the
exception that the free end of the blank 91A is provided
with an end notch 92 to define a pair of finger portions 93
for engaging and retaining a wire conductor, as
hereinbefore described. In all other respects, the
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CA 02622237 2008-02-26
structure of embodiment Fig. 37 is similar to the wire
retainer 83 as described.
To complete the connector assembly 80, an end ring
insert 84 may be provided to protect the wire conductors
90A that extend beyond the outlet end 81B, as noted in Fig.
44. The illustrated ring inset 84 preferably formed of a
suitable plastic, comprises a ring body 84A having an
outwardly radially extending flange 84B. Blanked out of
the plane of the ring body are opposed tangs 84C which are
outwardly bent. The outer diameter of the ring body 84A is
slightly smaller than the diameter of the opening 82A
formed in the face portion of the external retainer ring
82. The arrangement is such that the ring insert 84 can be
readily snap fitted to the opening 82A of the external
retainer ring 82 and the outlet opening of the outlet end
portion 81B. The insert body tangs 84C function to enable
the ring insert 84 to be readily snap fitted to the outlet
end portion 81A, so that the ring insert 84 is prohibited
from being unintentionally separated therefrom.
Intermediate the opposed opening of the connector
body, there is provided a radially outwardly projecting
stop flange 95, which functions to limit the insertion of
the connector assembly through a knock-out hole of an
electric panel or electric box, as hereinbefore described.
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. '
Figs. 45 to 51 illustrate a further embodiment of the
invention. This embodiment of Figs. 45 to 51 is directed
to a snap-fit electrical connector assembly 100 which is
particularly suitable for attaching an electric cable or
conductor 101 to an electric box 102 which is disposed in a
finish wall structure 103.
It is frequently necessary to upgrade, repair, or add
new electric conductors or circuits to existing electric
boxes concealed within the wall of an existing structure.
In such instances, the installer is generally unable to
access a snap-fit connector so as to apply the necessary
pulling or pushing force necessary to insert and lock a
snap-fit connector assembly, e.g. 100, in a knockout
opening of the electric box 102. Heretofore, in such
situations, the installer generally utilized a connector
having a threaded outlet end which could be readily passed
through a knockout hole of an electric box, which could
then be secured by threading thereon a lock nut from within
the box opening, which is both difficult and time
consuming.
The connector assembly 100, as illustrated, includes a
connector body 104 having a leading end or outlet end 105
and a trailing or inlet end 106. The connector body may be
formed as a metal casting of a suitable material, e.g. a
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zinc alloy, having a bore 107 extending therethrough.
Circumscribing the connector body 104 between the outlet
end 105 and the inlet end 106 is a radially outwardly
extending stop flange 108. As hereinbefore described, the
outer surface S of the outlet end 105 tapers or converges
inwardly toward the central axis of the connector body 104
and the outlet opening 109.
Complementing the slope or taper of the outer surface
S of the outlet end 105 is a frustro-conical snap-fit
retainer ring 110 which is similar in structure
hereinbefore described with respect to Figs. 1 to 4, except
that the retaining slot 111 adapted to receive the
retaining lug 112 is enlarged, as compared to the retaining
slot 21 as hereinbefore described. As best seen in Figs.
47 and 48, the retaining slot 111 has a width which is
greater than the width of the retainer lug 112 adapted to
be received in slot 111 in the assembled position, as best
illustrated in Figs. 46 and 47. In all other respects, the
structure of the retainer ring 110 is similar to the
construction of retainer ring 18 hereinbefore described
with respect to the embodiments illustrated, for example in
Figs. 1 to 4, and which need not be repeated.
It will be understood that a conductor retainer means,
similar to any of those hereinbefore described with respect
CA 02622237 2008-02-26
to Fig. 8, Figs. 11-18, and Figs. 33-36 may be associated
with the inlet end 106 of the connector embodiment
illustrated in Figs. 45 to 48 for receiving and retaining
the wire conductor 101 to prohibit any unintentional
separation of the wire conductor 101 from the connector
assembly 100.
Because of the amount of force that is required to be
applied to the connector assemblies as herein described, it
has been noted that great difficulty has been encountered
in the field when installers or electricians attempted to
utilize snap-fit connectors for connecting wire conductors,
cable or the like to a knock-out opening 114 of an electric
box 102 seated within an established or finished wall
structure 103 as shown in Figs. 50 and 51. This is because
the installer had insufficient access to the connector
assembly to apply thereto the necessary pushing or pulling
force required to overcome the spring tension or deflection
of the locking tangs 113, required to seat the connector
assembly in the knockout opening 114 of the electric box
102 in a finished wall installation.
To facilitate seating and locking a snap-fit connector
assembly 100 in a knockout hole 114 of an electric box 102
supported in a finished or existing wall 103 as described
herein, this invention contemplates an installation tool
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CA 02622237 2008-02-26
120 which is designed to complement the circumference of
the outlet end 105 of the connector assembly 100. Since
the outlet end 105 and the circumscribing retainer ring 110
are frustro-conical and converge toward the outlet opening
109, the connector assembly 100, as shown in Fig. 50, can
be brought into ready alignment with the knockout opening
114. However, due to the outward flare of the locking
tangs and the trailing end of the frustro-conical retaining
ring 110, it is prohibited from being seated or locked to
the knockout hole 114, until such time that a sufficient
force is applied to effect the flexing of the locking tangs
113 and to a lesser extent, the grounding tangs 115.
As access to the connector assembly 100, as shown in
Fig. 50, is limited and prohibits an installer from
applying the necessary force to pull or push the connector
assembly 100 to seat and lock the connector assembly in the
knockout opening 114, an installation tool 120 is provided
to facilitate the seating and locking of the connector
assembly 100 to the electric box 102. As best seen in
Figs. 52 to 55, the installation tool 120 comprised simply
of an elongated flat metal plate 120A. Formed at one end
of the plate 120A is a generally U-shaped cutout 121 formed
with parallel edges 121A joined at the inner ends thereof
by an arcuate segment 121B shaped to complement the
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CA 02622237 2008-02-26
curvature or arcuate portion of the frustro-conical
retainer ring 110.
In accordance with this invention, the opposed
parallel edges 121A, 121A are sized and shaped to engage
the enlarged retaining slot 111 as the tool 120 in inserted
through the open end of the electric box 102, as best seen
in Fig. 50. It will be understood that the thickness of
the plate 120A at the parallel edges 121A, 121A of the
cutout portion 121 should be slightly less than the opposed
open area of the enlarged retaining slots 111. In the
event that the thickness of plate 120A at end 120A' is
greater than the open area of the enlarged retainer slot
111 formed in the retaining ring 110, a portion of the
plate 120A adjacent the parallel edges 121A, 121A, as best
seen in Fig. 52, may be machined away or removed as
indicated at 121C so as to reduce the thickness of the
parallel edges 121A, 121A an amount sufficient to permit
the opposed parallel edges 121A, 121A to be received in the
open or enlarged unoccupied area of the retainer slot 111.
Figs. 57 and 58 illustrate a slightly modified tool
embodiment 130. The tool embodiment 130 is similar to that
described with respect to Figs. 52-56 except that the
thickness of the plate 130A is uniform, i.e. the thickness
of the plate 130A is slightly less than the available open
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CA 02622237 2008-02-26
or unoccupied area of the enlarged retainer slot 111, which
is not occupied by the retainer lug 112 when the retainer
ring is assembled to the connector body. In tool
embodiment 130, the parallel edges 131A, 131A of cutout 131
need not require any machining or removal of any material
of the plate to size the thickness of the edges 131A, 131A,
as described with respect to tool 120.
Fig. 59 illustrates another slightly modified
embodiment of a tool 140. Tool 140 is similar to that
hereinbefore described, except that the other end of the
plate 140A is provided with a polygonic shaped cutout 142
to define an open end wrench sized and shaped to
accommodate a conventional complementary polygonic lock nut
(not shown) in the event a connector having an externally
threaded outlet end may sometimes be used to secure a wire
or cable to an electric box. Tool 140 thus has the
versatility to be used to secure either a conical snap-fit
connector assembly 100 as described herein, or a
conventional externally threaded connector assembly secured
by a lock nut, e.g. a hexagonic sided lock nut.
In operation, the connector assembly 100, with the
electrical conductor 101 attached thereto as described
herein, is disposed in alignment with a knockout hole 114
of an electrical box 102 installed in a finished wall 103.
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CA 02622237 2008-02-26
Since the connector assembly has a frustro-conical outlet
end, it can be readily positioned in a knockout hole 114
and rest therein so that the enlarged or unoccupied portion
of the retaining slot 111 is rendered accessible from
within the front opening 116 of the electric box 102, as
best seen in Fig. 50. Because of the outwardly bent
locking tangs 113, the connector assembly 100 cannot be
normally passed through the knockout hole 114 without a
pulling or pushing force being imparted onto the connector
assembly 100. Applying a pulling force on the individual
wires 101A of the conductor 101 is not advisable, as any
such pulling force may damage the insulated covering of the
individual wire conductors 101A or be pulled through the
connector assembly 100 depending upon the type or kind of
conductor retainer that is associated in the inlet end 106
of the connector body 104.
According to this invention, the locking of the
connector assembly 100 to the knockout hole 114 is
achieved, without any injury to the conducting wires,
simply by inserting the tool 120 through the open end 116
of the electric box 102 so that the parallel edges 121A,
121A of the cutout 121 engage the respective opposed
enlarged or unoccupied portion of the retaining slot 111
immediately below the retaining lugs 112, as indicated in
CA 02622237 2008-02-26
Figs. 48 to 50. This can be achieved by inserting the tool
120 into the electric box slightly below the upper end of
the electric box and substantially parallel thereto. With
the edges of the cutout 121 engaged in the opposed enlarged
or unoccupied portions of the retaining slots 111, an
upward force as indicated by the force arrow A (Fig. 51)
adjacent the outer end of the tool will cause the other end
of the tool 120 to pull the outlet end 105 through the
knockout hole 114 to seat and lock the connector assembly
100 and connected conductor or cable 101 to the electric
box with a minimum of effort quickly and simply with a
minimum of applied force. As noted in Fig. 51, the tool
120 functions as a lever that uses the corner or edge of
the electric box at the open end thereof as a fulcrum about
which the tool pivots, to pull the connector assembly
downwardly with sufficient force to flex the locking tangs
inwardly, permitting the connector assembly to pass through
the knockout hole 114, whereby the inherent spring energy
of the locking tangs causes the locking tangs to spring
outwardly and lock the connector assembly 100 in place
within the knockout hole.
Figs. 60-67 are directed to another embodiment of the
invention formed to enhance the grounding effect between
the connector assembly 200 and the electrical box or panel
56
CA 02622237 2008-02-26
,
,
201 to which the connector assembly 200 is attached. It
will be understood that the connector assembly 200 includes
a connector body similar to any of the connector body forms
herein described. For illustrative purposes, the connector
body 202 is similar to the connector body 11 illustrated
and described with respect to Fig. 1. In the embodiment
illustrated in Fig. 60, the outer frustro-conical retainer
ring 203 has been modified so as to enhance the grounding
effect between the connector assembly 200 and the electric
box or panel 201, to which the connector assembly 200 is
secured. This is attained by increasing the contact area
of the grounding tangs 207, 207A of the frustro-conical
retaining ring with the internal periphery 201A of the
knock-out hole 201, as will be hereinafter described.
In accordance with this invention, the frustro-conical
retainer ring 203 is preferably formed from a blank 204 of
a resilient type metallic material, e.g. spring steel,
which may have a generally circular configuration as shown
in Fig. 61 for illustrative purposes only. As shown, the
blank 204 is provided with a center hole or opening 205,
which defines the outlet opening 205A when the blank 204 is
formed into a frustro-conical ring, as illustrated in Figs.
60 and 62-64. Blanked, stamped or die cut out of the plane
of the blank 204 are a pair of opposed locking tangs 206,
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CA 02622237 2008-02-26
206A. The portions of the blank 204 disposed between the
opposed locking tangs 206, 206A to either side of the
locking tangs 206, 206A define the grounding tangs 207,
207A for enhancing the grounding effect when the blank is
formed into a frustro-conical ring, as shown in Figs. 65,
66.
Circumscribing the center hole 205 is a foldline f2
about which blank 204 is laterally bent, shaped or formed
to define a retainer ring a shown in Fig. 60. Such forming
may be accomplished by a progressive die or other forming
technique. In its formed state, as best seen in Figs. 60
and 65, the retainer ring 203 is provided at the leading
end thereof with a face portion 208 which circumscribes the
outlet opening 205A. The laterally outwardly sloping
grounding tangs 207, 207A define a curvilinear trailing
edge 209 having a diameter which is greater than that of
the leading edge that defines or circumscribes the face
portion 208. As shown in Figs. 60, 63 and 65, the
respective opposed locking tangs 206, 206A are angularly
bent outwardly of the ring 203 at an angle or slope which
is greater than the slope of the grounding tangs 207, 207A,
as best seen in Figs. 60, 63 and 65.
Formed in the plane of the respective grounding tangs
207, 207A is a retaining slot 210 arranged to receive a
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CA 02622237 2008-02-26
retaining lug 211 formed on the outlet end portion 212 of
the connector body 202. It will be understood that the
slot 210 may be sized as described with respect to the
embodiment illustrated in Fig. 1, or as described with
respect to the embodiment described with respect to Figs.
45-49 if the use of a tool 120, as hereinbefore described,
is required to secure the connector assembly to an electric
box or panel.
To minimize any damage to wires that are to extend out
through the outlet opening 205A, the outlet opening 205A
may be formed with a protective lip 213 to provide a smooth
surface about the outlet opening 205A through which the
conductor wire extends. It will be understood that the
protective lip 213 may be of any shape that will form a
smooth surface about the periphery of the outlet opening
205.
It is to be further understood that the frustro-
conical ring as described with respect to Figs. 60 to 67
may be utilized with any of the connector bodies herein
described.
As described, it will be noted the trailing edge 209
of the frustro-conical retaining ring 203 defines a
curvilinear trailing edge that approximates at least three
quarters or 270 of the circumference of the trailing end
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CA 02622237 2008-02-26
of the frustro-conical retainer ring 203. As the diameter
of the trailing edge 209 is formed slightly greater than
the diameter of the knock-out hole adapted to receive the
same and together with the inherent resiliency of the
spring metal grounding tangs, there is produced an inherent
spring bias whereby the grounding tangs are normally biased
outwardly to ensure positive engagement of the grounding
tangs 207, 207A with the internal periphery 201A of the
knock-out hole 201. Because of the approximately 270 or
extended contacting surface of the grounding tangs with the
internal peripheral surface of the knock-out hole and
coupled with inherent spring force or bias of the grounding
tangs to maintain the grounding tangs 207, 207A in positive
contact with the internal periphery of the hole 205, the
electrical grounding effect therebetween is substantially
enhanced and assured. In all other respects, the connector
assembly 200 functions as hereinbefore described.
Figs. 68 to 72 illustrate a further modified
embodiment of a frustro-conical retainer ring 220 which is
capable of further enhancing the grounding effect between a
connector assembly 221 and a knock-out hole 222 in an
electric box or panel 223. In this form of the invention,
the connector body 224 may be similar to any of the various
connector bodies hereinbefore described. Generally, the
CA 02622237 2008-02-26
connector body includes an inlet end portion 224A and a
frustro-conical outlet end portion 224B similar to that
hereinbefore described.
In this form of the invention, the connector body 224
is provided with a further modified frustro-conical
retainer ring 225. The frustro-conical ring 225 is formed
with a grounding tang 226 that has a circumference of 3600
that defines the trailing end 225A of the frustro-conical
ring 225. The modified retaining ring 225 may be formed
from a blank 230 of a resilient or spring metal, e.g.
spring steel, as shown in Fig. 68. The blank 230 includes
an outer circumference that defines the trailing edge 225A
of the retaining ring 225 in its fully formed state as
shown in Figs. 69-72. A center hole 230 is formed in the
blank 226 which defines the outlet opening 227A through
which a wire conductor may be extended. As shown in Fig.
68, a pair of opposed locking tangs 228, 228 are formed in
the plane of the blank 230, which are arranged to be
outwardly bent from the plane of the blank as the blank 230
is progressively worked to form the retainer ring into its
finally formed state as shown in Figs. 69 to 70.
In this form of the invention, the outer free ends
228A of the locking tangs 228 are disposed inwardly of the
outer edge 225A of the blank 225. As a result, the
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CA 02622237 2008-02-26
trailing outer edge 225A of the fully formed frustro-
conical retaining ring 225 defines a grounding surface
about the entire circumference of the frustro-conical
retaining ring 225 at its trailing edge.
Oppositely disposed and off-set approximately 900 from
the respective locking tangs 228, 228, the blank 230 is
formed with opposed slots 229, 229, which are sized and
arranged to receive the retaining lugs formed on the outlet
end portion 2243 as hereinbefore described with respect to
Fig. 1 or as described with respect to Figs. 45-51 for
accommodating a tool 120.
It will be understood that the blank 230 is
transformed into a ring shape by subjecting the blank 230
through progressive dies whereby the portion of the blank
230 circumscribing the central opening or hole 227 is
laterally and outwardly sloped, bent, or formed into a
frustro-conical ring as illustrated in Figs. 69-71. In its
formed state, the frustro-conical ring includes a face
portion 225B which defines the leading end of the retainer
ring 225 having a diameter which is less than the diameter
defined by the trailing edge 225A.
In this form of the invention, it will be noted that
the grounding tang is defined by the sloping surface S1 of
the frustro-conical ring 225 which, at the trailing edge
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CA 02622237 2015-09-14
225A, defines a contact surface about the entire
circumference of the retainer ring 225, i.e. 360 .
As noted in Fig. 72, the entire circumference of 3600
is biased in direct contact with the internal periphery of
the knock-out hole 222 of the electric box or panel 223.
The inherent spring bias of'the sloping surface SI that
defines a grounding tang assures a positive electrical
grounding between the retainer ring 225 and the electric
box or panel 223. In all other respects, the embodiment of
Figs. 68-72 functions as hereinbefore described.
The enhanced contact surface at the trailing edge of
the respective frustro-conical retainer rings 203 and 225
with the inner periphery surface of a knock-out hole of an
electric box or panel assures that the desired grounding
effect is achieved when used with thin walled boxes or
panels.
While the present invention has been described with
respect to several embodiments, it will be understood that
various modifications may be made without departing from
the scope of the invention.
63
