Note: Descriptions are shown in the official language in which they were submitted.
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PLUG WITH HOLDING MEANS FOR COUNTERBALANCING MECHANISM,
DOOR ASSEMBLY INCLUDING THE SAME AND METHOD OF INSTALLING
ASSOCIATED THERETO
Field of the invention:
The present invention relates to a plug, also known as a cone, an anchor, or a
collar, as used in counterbalancing mechanisms of door assemblies, such as
garage doors and the like. The present invention is particularly advantageous
in
that it enables to facilitate the installation of a plug onto a torsion spring
of a
counterbalancing mechanism, for operatively connecting the torsion spring onto
a
corresponding component of the counterbalancing mechanism, so as to or allow
a proper torque transfer between the torsion spring and the corresponding
component. The present invention has been namely developed in order to ease
the installation of torsion springs used to counterbalance garage doors and
the
like, as well as truck door weights, in the truck door industry for example.
The
present invention may also be used in other situations requiring the
attachment of
a torsion spring onto a corresponding component of another type of mechanism
or assembly.
Backctround of the invention:
It is known in the art that most garage doors currently used are
counterbalanced
by different suitable means. Some doors are counterbalanced by means of a
counterweight and other doors are counterbalanced by means of an energy-
storing device, such as a spring under traction or torsion for example. These
counterbalancing systems are typically used to ease the force required by a
user
or a motorized door system to raise and lower the door. In order to put a
spring
under tension, an installer typically must wind the spring and maintain a
given
torque or tension in the spring by different methods and apparatuses.
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It is also known in the art that the most common way to wind a spring within a
counterbalancing mechanism is to use a device known as a "plug", or "cone",
which is typically inserted into a corresponding torsion spring by friction.
The plug,
or cone, generally has holes which are used to wind the spring with an
appropriate winding tool, such as a winding bar, when the system is installed
into
place.
Known in the art are also the numerous problems associated with conventional
plugs. A first problem resides in the spring insertion onto the so-called
plug, as
the plug must be maintained during spring insertion, a special jig has to be
thus
created. Another resulting problem occurs during installation, particularly in
the
truck door industry, where the space around the plug is very limited, thus
making
it difficult to move the winding bar required to wind the plug. Furthermore,
another
resulting problem resides in that, once again, typically in the truck door
industry,
when the system is wound, usually the so-called plug is screwed against the
shaft
but a conventional plug has only two screws which thereby limits the plug
position
in terms of counterbalancing possibilities.
Hence, in light of the aforementioned, there is a need for an improved plug
which,
by virtue of its design and components, would be able to overcome some of the
aforementioned problems.
Summary of the invention:
The object of the present invention is to provide an improved plug which
satisfies
some of the above-mentioned needs and which is thus an improvement over
other related plugs known in the prior art.
In accordance with the present invention, the above object is achieved, as
will be
easily understood, with a plug such as the one briefly described herein and
such
as the one exemplified in the accompanying drawings.
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According to the present invention, there is provided a plug, substantially
cylindrical in shape and having a longitudinal central axis, for use with a
counterbalancing mechanism of a door assembly, the counterbalancing
mechanism including a shaft and a torsion spring mounted coaxially about the
shaft, the torsion spring having a plurality of coils, and opposite first and
second
ends, the plug being mountable about the shaft and used for operatively
connecting one of the ends of the torsion spring onto said shaft of the
counterbalancing mechanism for allowing a torque transfer between the torsion
spring and the shaft, the plug comprising:
a first portion extending about the longitudinal central axis of the plug,
said first portion being provided with connecting means for removably
connecting
the plug onto said one of the ends of the torsion spring;
a second portion also extending about the longitudinal central axis of
the plug, adjacent to the first portion and operatively connected thereto, the
second portion being provided with at least one hole for receiving a winding
tool
for winding the plug about the shaft; and
a third portion also extending about the longitudinal central axis of the
plug, adjacent to the second portion and operatively connected thereto, the
third
portion being provided with affixing means for securely affixing the plug onto
the
shaft ounce wound.
Preferably, the connecting means comprise threading provided about the first
portion for threadedly engaging the plug onto corresponding coifs of said one
of
the ends of the torsion spring.
Preferably also, the affixing means comprise at least one set screw theradedly
movable within an orifice and having a tip operable between a locked
configuration where the tip is away from the shaft, thereby enabling the plug
to
rotate about the shaft, and an unlocked configuration where the tip is forced
against the shaft for preventing the plug from rotating about said shaft.
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Preferably also, the third portion of the plug is provided with holding means.
Preferably, the holding means comprise at least one embossment.
Preferably also, the first, second and third portions of the plug are made
integral
to each other.
According to another aspect of the invention, there is also provided a
counterbalancing mechanism provided with the above-mentioned plug.
According to yet another aspect of the invention, there is also provided the
garage door provided with the above-mentioned counterbalancing mechanism.
According to yet another aspect of the invention, there is also provided a
method
of installing the above-mentioned plug onto a counterbalancing mechanism.
The objects, advantages and other features of the present invention will
become
more apparent upon reading of the following non-restrictive description of a
preferred embodiment thereof, given for the purpose of exemplification only
with
reference to the accompanying drawings.
Brief descriation of the drawings:
Figure 1 is a perspective view of a plug according to the prior art.
Figure 2 is another perspective view of the plug shown in Figure 1.
Figure 3 is a perspective view of a plug according to the preferred embodiment
of
the present invention, said plug being shown provided with setscrews.
Figure 4 is a perspective view of the plug of Figure 3 shown installed onto a
corresponding counterbalancing mechanism of a door assembly, the plug being
shown with a winding tool inserted into a corresponding hole thereof.
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Detailed description of a preferred embodiment of the invention:
In the following description, the same numerical references refer to similar
5 elements. The embodiments shown in Figures 3 and 4 are preferred.
In the context of the present description, the expression "door assembly"
includes
various types of door assemblies, such as rolling door assemblies (e.g. mini-
warehouse doors, truck door assemblies, commercial rolling steel doors, etc.)
and the like. Although the present invention was primarily designed for a
garage
door assembly, it may be used with other kinds of assemblies, such as fire
doors
or shutters, or with any other door assemblies provided with counterbalancing,
winding, and/or controlling mechanisms requiring a torsion spring to be
connected to a corresponding component, as apparent to a person skilled in the
art. For this reason, the expression "counterbalancing" andlor "door assembly"
should not be taken as to limit the scope of the present invention and
includes all
other kinds of assemblies or items with which the present invention may be
used
and could be useful.
Moreover, in the context of the present description, the expressions "door"
and
"assembly", "plug" and "collar", "counterbalancing" and "controlling",
"mechanism" and "system", "winding" and "counterbalancing", as well as any
other equivalent expressions andlor compound words thereof, may be used
interchangeably. The same applies for any other mutually equivalent
expressions,
such as "winding tool" and "winding bar" for example, as apparent to a person
skilled in the art.
In addition, although the preferred embodiment of the present invention as
illustrated in the accompanying drawings comprises various components such as
hole(s), threading, setscrew(s), embossment(s), etc., and although the
preferred
embodiment of the plug 1 and corresponding parts of the present invention as
shown consists of certain geometrical configurations as explained and
illustrated
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herein, not all of these components and geometries are essential to the
invention
and thus should not be taken in their restrictive sense, i.e. should not be
taken as
to limit the scope of the present invention. It is to be understood, as also
apparent
to a person skilled in the art, that other suitable components and
cooperations
thereinbetween, as welt as other suitable geometrical configurations may be
used
for the plug 1 according to the present invention, as will be briefly
explained
herein and as can be easily inferred herefrom, without departing from the
scope
of the invention.
Broadly described, the present invention, as shown in the accompanying
drawings, relates to a plug 1 with holding means for use with a
counterbalancing
mechanism, and also relates to a door assembly including the same, as well as
a
method of installing the plug 1 onto the counterbalancing mechanism.
As better shown in Figure 3, the plug 1 is preferably substantially
cylindrical in
shape, and has a longitudinal central axis 3. The plug 1 is typically for use
with a
counterbalancing mechanism of a door assembly, such as garage door, a truck
door, and the like. As better shown in Figure 4, the counterbalancing
mechanism
typically includes a shaft 5, and a torsion spring 7 mounted coaxially about
the
shaft 5, the torsion spring 7 having a plurality of coils 9, and opposite
first and
second ends. As also better illustrated in this figure, the plug 1 is
mountable
about the shaft 5 and used for operatively connecting one of the ends of the
torsion spring 7 onto said shaft 5 of the counterbalancing mechanism for
allowing
a proper torque transfer between the torsion spring 7 and the shaft 5, as is
known
in the art, and as apparent to a person skilled in this field.
Referring back to Figure 3, the plug 1 preferably comprises a first portion
11, a
second portion 13, and a third portion 15. The first portion 11 preferably
extends
about the longitudinal central axis 3 of the plug 1, and is provided with
connecting
means 17 for removably connecting the plug 1 onto a corresponding end of the
torsion spring 7, as better shown in Figure 4.
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The second portion 13 also preferably extends about the longitudinal central
axis
3 of the plug 1, is preferably adjacent to the first portion 11 and
operatively
connected thereto, and is also preferably provided with at least one hole 19
for
receiving a winding tool 21 for winding the plug 1 about the shaft 5, as also
better
shown in Figure 4.
The third portion 15 of the plug 1 also preferably extends about the
longitudinal
central axis 3, adjacent to the second portion 13 and operatively connected
thereto, and is also preferably provided with affixing means 23 for securely
affixing the plug 1 onto the shaft 5 once wound, as can easily be understood
when referring to Figure 4.
As better shown in Figure 3, the connecting means 17 preferably comprise
threading 25 provided about the first portion 11 of the plug 1 for threadely
engaging the plug 1 onto corresponding coils 9 of the corresponding end of the
torsion spring 7.
As also shown in this figure, the affixing means 23 preferably comprise at
least
one setscrew 27 threadely moveable within an orifice and having a tip operable
between a locked configuration where the tip is away from the shaft 5, thereby
enabling the plug 1 to rotate about the shaft 5, and an unlocked configuration
where the tip is forced against the shaft 5 for preventing the plug 1 from
rotating
about the shaft 5.
Preferably also, as shown in Figure 3, the third portion 15 of the plug 1 is
provided with holding means, these holding means preferably comprising at
least
one embossment 29. This special embossment 29 is preferably used to block the
plug 1 onto the spring insertion machine. Preferably also, six winding holes
19
are provided about the second portion 13, at 60° from each other, to
increase
possibilities of adjustment. Preferably also, the plug extension (third
section 15) is
used to place preferably four setscrews 27 all around the plug 1 to give
access to
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at least two screws 27 in any plug position around the shaft 5, as can be
easily
understood when referring to Figure 4.
In its normal use, the plug 1 is preferably inserted into a jig adapted to
receive the
plug embossment 29 and then, the spring 7 is wound all around the threaded
plug 1 section. As can be easily understood, the above-described and
illustrated
embossments allow a fast and easy installation.
In the field or work site, when the system is installed around the shaft 5,
the
installer uses a winding bar 21 inserted into the winding holes 19 to wind the
plug
1 around the shaft 5 as is the case with an ordinary plug, but the preferred
six
winding holes 19 make the operation a lot more easier by allowing more room
for
the installer to turn the plug 1 around the shaft 5.
When the required torsion torque is reached in the spring 7, two screws 27 are
still accessible to be screwed to hold the torque against the shaft 5.
It is worth mentioning that according to the present invention, the plug 1
need not
be substantially symmetrical andlor cylindrical in order for it to carry out
its proper
functions. Indeed, the plug 1 according to the preferred embodiments of the
present invention is preferably made substantially cylindrical in order to
substantially match the corresponding conventional shape of the torsion spring
7
into which the first portion 11 is inserted, but it is worth mentioning that
the plug 1
may take on various other suitable cross-sectional configurations so long as
it is
provided with the above-described components and the holding means, in order
to enable the plug 1 to be installed onto the end of the torsion spring 7 in
an
easier manner, as above-discussed, and as apparent to a person skilled in the
art.
Preferably, the various components of the plug, such as the first, second and
third sections 11, 13, 15 threading 25, embossments 29, etc., are made of one
single piece and of one single material. Various manufacturing processes
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(molding, casting, and the like) and various suitable corresponding materials
may
be used for fabricating the plug 1 according to the present invention, as
apparent
to a person skilled in the art. Preferably, the plug 1 is made of a suitable
rigid
material, such as a metallic material (e.g. steel, etc.), or a hardened
polymer,
although other suitable materials, such as composite materials, etc., may be
used
depending on the particular applications for which the plug 1 is intended, and
the
loads it is subject to, as also apparent to a person skilled in the art.
According to another aspect of the present invention, there is also provided a
counterbalancing mechanism provided with the above-described plug 1.
According to yet another aspect of the present invention, there is also
provided a
door assembly having a counterbalancing mechanism provided with the above-
described plug 1. According to yet another aspect of the present invention,
there
is also provided a method of installing the above-described plug 1 onto
corresponding components of a counterbalancing mechanism .
As may now be better appreciated, the present invention is a substantial
improvement and presents several advantages over devices and/or methods
known on the prior art. Indeed, the present invention may be used in the
garage
door industry, with new door assemblies or existing door assemblies. The plug
1
according to the present invention is particularly advantageous in that, by
virtue of
its design and components, as explained hereinabove, the plug 1 may be
mounted onto the end of the torsional spring 7 in an easier and faster manner,
which reduces the installation time and physical requirements which would
likely
to be needed otherwise with conventional plugs such as the ones illustrated in
Figures 1 and 2. Hence, in view of the above, it may now be appreciated that
the
present invention represents an important advantage over previous devices
known in the prior art, in terms of safety, time, performance and costs.
Of course, numerous modifications could be made to the above-described
embodiments without departing from the scope of the invention as apparent to a
person skilled in the art.
