Note: Descriptions are shown in the official language in which they were submitted.
CA 02425108 2003-04-10
1
RATCHET-LIKE SYSTEM FOR VIIINDING A ROLf ING DOOR ASSEMBLY
Field of the invention:
The present invention relates to a ratchet-like system. More particularly,
the present invention relates to a ratchet-like system for winding a rolling
door
assembly, such as mini-warehouse doors, commercial rolling steel doors, and
the
like, for example. The present invention also relates to a rolling door
assembly
provided with such a ratchet-like system and to a kit for assembling the
ratchet-like
system. The ratchet-like system is namely intended to adjustably control the
rotation of the overhead shaft of the rolling door assembly during the winding
thereof.
Background of the invention:
Rolling door assemblies, such as mini-warehouse doors, commercial
rolling steel doors, and the like, are very well known in the art.
These rolling door assemblies typically comprise an overhead shaft
which is mounted onto a fixed structure, a drum mounted about the overhead
shaft, and a door curtain foldable (i.e. wound, coiled-up, etc.) about the
drum and
unfoldable from the same via a rotation of the drum so as to alternatively
lower
and raise the curtain, i.e. operate the door. Generally, these rolling door
assemblies also generally comprise at least one, but typically a pair of,
counterbalancing springs) having ends operatively connected to corresponding
parts of the assembly for providing the same with a suitable counterbalancing
force. This counterbalancing force is used in order to decrease force required
to
open the door and also facilitate its closing.
Also known in the art are two main types of rolling door assemblies,
namely "dead shaft°' rolling door assemblies and "live shaft'°
rolling door
assemblies.
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A °'dead shaft" rolling door assembly is one in which, after
proper
installation thereof, the overhead shaft is securely fixed and tightened onto
the
support structure by means of brackets and corresponding fasteners, and thus
does not rotate during normal operation of the rolling door assembly. In
contrast, a
"Live shaft" rolling door assembly is one in which, after proper installation
thereof,
the overhead shaft is pivotally connected to the fixed structure and rotates
thereabout during normal operation of the rolling door assembly.
In the case of a "dead shaft°' rolling door assembly, the drum is
pivotally
mounted about the overhead shaft and rotates thereabout, and each
counterbalancing spring typically has first and second ends mounted onto the
shaft and drum respectively so as to be wound and unwound accordingly,
depending on the operation of the door assembly, so as to provide a
corresponding counterbalancing force thereto.
In the case of a "live shaft" rolling door assembly, the drum is securely
mounted about the overhead shaft and rotatable therE;with with respect to the
fixed
structure, and each counterbalancing spring typically has first and second
ends
mounted onto the drum and the fixed structure respectively so as to be wound
and
unwound accordingly, depending on the operation of the door assembly, so as to
provide a corresponding counterbalancing force thereto.
It is also known in the art that with "dead shaft" rolling door assemblies
for example, the winding thereof needs to be property calibrated in order to
ensure
a suitable operation of the door assembly. Typically, an installer must
untighten
the brackets so as to untighten the overhead shaft of the assembly from its
fixed
structure, and rotate said shaft with respect to the drum by means of a tool,
such
as a pipe wrench for example, in order to provide the counterbalancing spring
with
a suitable load, such that the latter may offer a corresponding suitable
counterbalancing force. A problem associated with this type of winding is that
it is
carried out at elevated heights, typically using a ladder, given the fact that
the
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3
overhead shafts of roiling door assemblies are generally located well above
ground level or well out of human reach. Another problem associated with this
type
of winding is that an installer must typically use both hands to secure
movements
of the assembly and also operate the pipe wrench in order to secure movement
of
the overhead shaft with respect to the drum. Another problem associated with
the
above-mentioned type of winding is that the rolling door assembly and the
parts
thereof are generally quite heavy, and thus a considerable effort is required
from
the installer to carry out the above-mentioned maneuvers, often causing him to
force onto the parts and causing him also to undertake very precarious
movements and/or positions, which can be very dangerous. Another problem
associated with this type of winding is that if the rolling door assembly is
not
property held into place by the installer during the winding phase, the shaft
may
start to roll and thus the door assembly may fall to the ground, which is very
disadvantageous. The above-discussed problems have been known to give rise to
substantial damages to property andlor serious injuries to people.
Hence, in light of the aforementioned, there is a need for an improved
system and/or method for winding a rolling door assembly which would be able
to
overcome some of the aforementioned problems,
Summary of the invention:
The object of the present invention is to provide a system which, by
virtue of its design and components, satisfies some of the above-mentioned
needs
and is thus an improvement over other known devices andfor methods in the
prior
art.
The present invention is particularly advantageous in that it is intended
to adjustably control the rotation of the overhead shaft of the rolling door
assembly
during the winding thereof.
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In accordance with the present invention, the above object is achieved
with a ratchet-like system for winding a rolling door assembly having an
overhead
shaft mounted about a fixed structure and rotatable thereabout slang opposite
first
and second directions, a drum mounted about said overhead shaft, a door
curtain
foldable about the drum and unfoldable from the same via a rotation of the
drum,
and a counterbalancing spring operatively connected between the overhead shaft
and the drum for counterbalancing the rolling door assembly when the overhead
shaft is secured to the axed structure, the ratchet-like system comprising;
at least one support bracket;
at least one cam pivotally mounted about the at least one support
bracket and positioned adjacent to a portion of the overhead shaft, said at
least
one cam being shaped and sized to cooperate with said portion of the overhead
shaft between a first position, where the at least one cam allows rotation of
the
overhead shaft along the first direction, and a second position, where the at
least
one cam has a surface engaged with the overhead shaft and where further
rotation of the overhead shaft along the second direction is blocked by the at
least
one cam; and
biasing means for urging the surface of the at least one cam onto the
overhead shaft.
According to another aspect of the present invention, there is also
provided a ratchet-like system for winding a rolling door assembly having an
overhead shaft mounted about a fixed structure and rotatable thereabout along
opposite first and second directions, the ratchet-like system comprising;
at least one support bracket;
at least one cam pivotally mounted about the at least one support
bracket and positioned adjacent to a portion of the overhead shaft, said at
least
one cam being shaped and sized to cooperate with said portion of the overhead
shaft between a first position, where the at least one cam allows rotation of
the
overhead shaft along the first direction, and a second position, where the at
least
one cam has a surface engaged with the overhead shaft and where further
CA 02425108 2003-04-10
rotation of the overhead shaft along the second direction is blocked by the at
(east
one cam; and
biasing means for urging the surface of the at least one cam onto the
overhead.
According to yet another aspect of the present invention, there is also
provided a kit for assembling a ratchet-like system for winding a rolling door
assembly having an overhead shaft mounted about a fixed structure and
rotatable
thereabout along opposite first and second directions, a drum mounted about
said
overhead shaft, a door curtain foldable about the drum and unfoldable from the
same via a rotation of the drum, and a counterbalancing spring operatively
connected between the overhead shaft and the drum for counterbalancing the
rolling door assembly when the overhead shaft is secured to the fixed
structure,
the kit comprising:
a support bracket; and
a cam pivotally mountable about the support bracket and positionable
adjacent to a portion of the overhead shaft, said cam being shaped and sized
so
that, once the ratchet-like system assembled, the corn cooperates with said
portion of the overhead shaft between a first position, where the cam allows
rotation of the overhead shaft along the first direction, and a second
position,
where the cam has a surface engaged with the overhead shaft and where further
rotation of the overhead shaft along the second direction is blocked by the
cam.
The objects, advantages and other features of the present invention will
become more apparent upon reading of the following non-restrictive description
of
preferred embodiments thereof, given for the purpose of exemplification only
with
reference to the accompanying drawings.
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Brief description of the drawings:
Figure 1 is a perspective view of a ratchet-Like system according to a
first preferred embodiment of the invention, said ratchet-like system being
shown
mounted onto a fixed structure.
Figure 2 is another perspective view of what is shown in Figure 1.
Figure 3 is an exploded view of the ratchet-like system of Figure 1, said
ratchet-like system being shown in relation to a rolling door assembly and a
fixed
structure.
Figure 4 is an assembled view of what is shown in Figure 3, the
overhead shaft of the rolling door assembly being shown adjusted by means of a
pipe wrench.
Figure 5 is a front plan view of the ratchet-Bike system of Figure 4
cooperating with the overhead shaft of the rolling door assembly, the overhead
shaft being shown rotated along a first direction.
Figure 6 is another front plan view of what is shown in Figure 5, the
overhead shaft being now shown blocked by a cam when rotated along a second
direction.
Figure 7 is an exploded view of a ratchet-like system according to
another preferred embodiment of the invention.
Figure 8 is a top plan view of the ratchet-tike system of Figure 7 shown
in an assembled configuration.
Figure 9 is a side elevational view of what is shown in Figure 8.
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Figure 10 is a cross-sectional view taken along line X-X of the ratchet-
like system shown in Figure 9.
Figure 11 is a cross-sectional view taken along line XI-XI of the ratchet-
s like system shown in Figure 9.
Figure 12 is a perspective view of a ratchet-like system according to yet
another preferred embodiment of the invention, said ratchet-like system being
used as a winding tool.
Figure 13 is a perspective view of the ratchet-like system of Figure 12,
said ratchet-like system being shown cooperating with an overhead shaft when
rotated along a first direction.
Figure 14 is another perspective view of the ratchet-like system of
Figure 12, the ratchet-like system being shown cooperating with an overhead
shaft, said overhead shaft being shown blocked by a cam when rotated along a
second direction.
Detailed description of a preferred embodiment of~ the irdvention:
In the following description, the same numerical references refer to
similar elements. The embodiments shown in the figures are preferred.
In the context of the present description, the expression "rolling door
assembly" includes various types of rolling door assemblies, such as mini-
warehouse doors, commercial rolling steel doors, and the like. Although the
present invention was primarily designed for a dead shaft rolling door
assembly, it
may be used with other kinds of rolling door assemblies, such as fire doors or
shutters, or with any other door assemblies using an overhead shaft, whether
"dead" or "live", as apparent to a person skilled in the art. For this reason,
the
expression "dead shaft" and/or "roiling door assembly" should not be taken as
to
CA 02425108 2003-04-10
limit the scope of the present invention and includes all other kinds of doors
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'°, "curtain'" and "door", "counterbalancing shaft"
and
"overhead shaft", "system" and "device", 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 "plate"
and
"bracket" far 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 an orifice, fasteners, a safety device, a spring, a lever arrn, a knurled
surface, a
second cam, etc., and although the preferred embodiment of ratchet-like system
1
and corresponding parts of the present invention a s shown consists of certain
geometrical configurations as explained and illustrated 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 well
as
other suitable geometrical configurations may be used for the ratchet-like
system 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 ratchet-line system 1 according to the present
invention, as exemplified in the accompanying drawings, is a ratchet-like
system 1
devised to facilitate the winding of a rolling door assembly 3, such as mini-
warehouse doors, commercial rolling steel doors, and the like, but may also be
used for other types of installations where a torque must be applied onto a
shaft 5
and where said torque must be maintained.
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The ratchet-like system 1 according to the present invention is
particularly useful for winding a rolling door assembly 3 having an overhead
shaft
mounted about a fixed structure 7 and rotatable thereabout along opposite
first
and second directions. The rolling door assembly 3 generally further comprises
a
5 drum 9 mounted about the overhead shaft 5 and a door cu~~tain 11 foldable
about
the drum 9 and unfoldable from the same via rotation of the drum 9. The
rolling
door assembly 3 may also comprise a counterbalancing spring (not shown)
operatively connected between corresponding parts of the assembly 3 for
counterbalancing the same. In the case of a "dead shaft" rolling door assembly
3
for example, the counterbalancing spring is operatively connected between the
overhead shaft 5 and the drum 9 for counterbalancing the rolling door assembly
3
when the overhead shaft 5 is secured to the fixed structure, typically by
means of
U-shaped brackets and corresponding fasteners for example. It is worth
mentioning that, instead of using a counterbalancing spring, the rolling door
assembly 3 according to the present invention rnay be counterbalanced by other
suitable means, such as counterweights for example, as apparent to a person
skilled in the art.
According to the present invention, and as better shown in Figures 1-6,
the ratchet-like system 1 comprises at least one support bracket 13, at least
one
cam 15, and biasing means 17. As better shown in Figures 3-5, the support
bracket 13 is preferably securely mountable onto the fixed structure 7 of the
corresponding rolling door assembly 3 by means of suitable fasteners 19, but
may
also consist of a movable support bracket 13, in which case the ratchet-like
system 1 is used as a winding tool, as better shown in Figures 12-14. When the
ratchet-like system 1 is used as a winding tool, the support bracket 13 is
preferably
provided with an actuating arm 14.
The cam 15 according to the present invention is pivotally mounted
about the support bracket 13 and positioned adjacent to a portion of the
overhead
shaft 5. The cam 15 is shaped and sized to cooperate with said portion of the
overhead shaft 5 between a first position, where the c:am 15 allows the
rotation of
CA 02425108 2003-04-10
the overhead shaft 5 along a first direction 21, as better shown in Figures 5
and
13, and a second position, where the cam 15 has a surface 23 engaged with the
overhead shaft 5 and where further rotation of the overhead shaft 5 along a
second direction 25, opposite to the above-mentioned first direction 21, is
blocked
5 by the cam 15, as better shown in Figures 6 and '14. Hence, as can be easily
understood, the cam 15 of the ratchet-like system 1 is preferably devised to
enable
a user thereof to adjustably control the rotation of the overhead shaft 5 of
the
rolling door assembly 3 during the winding thereof. Namely, the ratchet-like
system
1 according to the present invention is preferably intended to allow rotation
of the
10 overhead shaft 5 in one direction 21, but preferably devised to impede
rotation
thereof along a opposite second direction 25, so as to facilitate manipulating
of the
rolling door assembly 3 and corresponding parts during the winding thereof.
The biasing means 17 are preferably devised fog- urging the surface 23
of the cam 15 onto the overhead shaft 5 so as to preferably ensure a
substantial
and/or continuous contact between the cam 15 and the surface of the overhead
shaft 5, as shown in Figures 5 and 6, and thus ensure a fairly rapid blocking
of the
overhead shaft 5 when the latter is rotated along the second apposite
direction 25,
as apparent to a person skilled in the art.
As also better shown in Figures 5 and 0, the biasing means 17 are
operatively connected between the support bracket 13 and the cam 15 so as to
exert a biasing force for biasing the surface 23 of the cam 15 towards the
overhead shaft 5. The biasing means 17 preferably comprise a loaded spring
member 27, capable of storing potential energy via deformation so as to
provide a
potential force, the spring member 27 having a first end operatively connected
to
the support bracket 13 and a second end operatively connected to the cam 15.
It
is worth mentioning however that other suitable biasing mdeans 17 which do not
use potential energy for providing a biasing force may be used according to
the
present invention, so long as these biasing means 17 are capable of biasing
the
surface 23 of cam 15 in a suitable way towards the overhead shaft 5, as
apparent
to a person skilled in the art.
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11
As better shown in Figures 5, 9, and 12, the cam 15 is preferably an
oval-shaped (e.g. round, ellipse, etc.) cam 15 being eccentrically mounted
onto the
support bracket 13. It is worth mentioning though that other suitable
geometries
and dispositions can be used for the cam 15 and corresponding support bracket
13 so as to ensure a rotation of the overhead shaft 5 along a first direction
21 but
also prevent the latter from being rotated when rotated in a second opposite
direction 25.
Preferably, as aforementioned, the biasing means 17 comprise a
loaded spring 27 being operatively connected between the support bracket 13
and
the cam 15. Preferably also, the spring member 2~7 has first and second ends
operatively connected to the support bracket 13 and the cam 15 respectively,
as
better shown in Figures 1-6. Once again, it is worth mentioning that the
biasing
means 17 may have other suitable dispositions on the ratchet-like system 1 so
as
to ensure a corresponding biasing force on the cam 15 towards the overhead
shaft
5. Indeed, for example, as better shown in Figures 7-8, the biasing means 17
may
comprise a spring member 27 having first and second ends operatively connected
to the support bracket 13 and a pin 29 about which the cams 15 are mounted. It
is
also worth mentioning that, according to the present invention, the spring
member
27 is not absolutely necessary for proper operation of the ratchet-like system
1.
indeed, the biasing means 17 may simply consist of the effect of gravity
acting on
the cams) 15, in which case, the cams) 15 would' be positioned, shaped, and
sized onto the support bracket 13 so that, by virtue of the effect of gravity
acting
thereon, it would have a surface 23 in physical contact with the overhead
shaft 5,
as apparent to a person skilled in the art.
As better shown in Figures 1-6, the support bracket 13 preferably has
an opening 31 through which extends the overhead shaft 5, and the fixed
structure
7 about which the support bracket 13 is mounted preferably has corresponding
supporting lips 33 about which the overhead shaft 5 may be rested.
Alternatively,
the support bracket 13 preferably comprises an orifice 35 through which
extends
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12
the overhead shaft 5, as better shown in Figures 7-14. It may be appreciated
that
a support bracket 13 with such an orifice 35 is substantially more rigid sound
than
a U-shaped bracket 13, as shown in Figures 1-6, and that the orifice 35 of
said
support bracket 13 may be used as a guiding and support device for the
overhead
shaft 5.
Although not absolutely necessary for proper operation of the ratchet-
like system 1 according to the present invention, the latter preferably
comprises a
safety device 37 being mounted about the support bracket 13 and being movable
with respect to the same, the safety device 37 having an end 39 adjacent to a
contact point on the overhead shaft 5, and this end 39 of the safety device 37
being operable between a first position where said end is away from the
contact
point of the overhead shaft 5, and a second position, where the end 39 is
secured
against the contact point of the overhead shaft 5 for immobilizing the
overhead
shaft 5 from being rotated along either direction with respect to the support
bracket
13 of the ratchet-like system 1. Indeed, once the rolling door assembly 3 has
been
properly wound (i.e. adjusted, calibrated, counterbalanced, etc.}, the ratchet-
like
system 1 according to the present invention and corresponding cams} 15 prevent
adverse rotation of the overhead shaft 5 along a second opposite direction 25,
and
thus acts as a stopper for such a rotation. As a protective measure, the
ratchet-like
system 1 may comprise the above-mentioned safety device 37 for maintaining the
overhead shaft 5 in a stable and fixed configuration, upon proper winding of
the
rolling door assembly 3, so as to not have to rely entirely on the ratchet-
like
system 1. Thus, as can be easily appreciated, the safety device 37 of the
ratchet-
like system 1 is not an essential feature thereof but provides the same with
substantial advantages. Preferably, as better shown in Figures 7-9, the safety
device 37 may consist of a suitable fastener 41 threadedly engaged into a
corresponding nut 42 of the ratchet-like system 1, arid being adjustably
screwed or
unscrewed so as to selectively secure the same against the outer surface of
the
overhead shaft 5, and selectively, block rotation thereof. indeed, the safety
device
37 preferably consist of a simple fastener 41 hawing a first portion
threadedly
engaged onto the support bracket and/or a piece thereof, such as a flange as
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13
shown in Figure 1, and an end 39 cooperable with the overhead shaft 5 in the
manner discussed above.
As can be easily understood when referring to Figures 1-9, the support
bracket 13 of the ratchet-like system 1 according to the present invention is
preferably securely mountable onto the fixed structure by means of
corresponding
suitable fasteners 19, and the support bracket 13 preferably comprises
corresponding recesses 43 for receiving the fasteners 19. The fasteners 19 may
consist of a bolt combined with other suitable complementary pieces, such as a
nut 42, a washer, a spacer, and/or the Like, as exemplified in Figure 7 and as
apparent to a person skilled in the art.
Preferably also, as better shown in Figures 7-11, the cam 15 is provided
with a lever arm 45 for allowing a user of the ratchet-like system 1 to urge
the cam
15 away from the overhead shaft 5, so as to enable rotation of the overhead
shaft
5 along the second direction 25, during unwinding of the rolling door assembly
3, if
required.
Preferably also, as better shown in Figures 7-9, the support bracket 13
comprises protective flanges 47 shaped, positioned, and sized so as to cover a
substantial portion of the cams) 15, and prevent the cams) 15 from being
accidentally tampered with.
It is worth mentioning though that, according to the present invention,
the safety device 37 may be disposed otherwise on support bracket 13 and/or on
other parts of the ratchet-like system 1, as briefly described hereinbelow and
as
apparent to a person skilled in the art.
According to another aspect of the present invention, there is also
provided a kit comprising some or several of the preferred components
constituting the ratchet-like system 1 according to the present invention, as
exemplified in Figure 7, so that a user may employ these components and
CA 02425108 2003-04-10
14
assemble them so as to obtain a ratchet-like system 1 having the structural
components and displaying the features described hereinabove.
According to another aspect of 'the present invention, there is provided
a rolling door assembly 3 provided with the above-mentioned ratchet-like
system
1.
The ratchet-like system 1 and corresponding parts (support bracket 13,
cam 15, etc.) are preferably made of substantially rigid materials, such as
metallic
materials (steel, etc.), hardened polymers, composite materials, and/or the
like, so
as to ensure a proper operation thereof depending on the particular
applications
for which the ratchet-like system 1 is intended and the different parameters
in
cause (counterbalancing force in the spring, weight of the door, number of
cycles,
etc.), as apparent to a person skilled in the art.
Following is a typical use of the present ratchet-like system 1 intended
for winding a rolling door assembly 3. The shaft 5 of the assembly 3 which is
typically connected to a counterbalancing spring, as aforernentioned, is
preferably
placed on a fixed structure 7, such as wall brackets for example. Preferably
also,
the brackets 13 of the rolling door assembly 3 are then bolted to the
corresponding
wall brackets around the shaft 5. The system is then operational. A garage
door
installer can then turn the shaft 5 with a pipe wrench or a special tool, and
the
eccentric cam 15 will open and let the shaft 5 turn freely, as better shown in
Figures 5 and 13. When the installer stops turning the shaft, the shaft being
now
under tension created by the torque spring on the door assembly 3, said torque
is
maintained by the cam effect which blocks the overhead shaft 5 from being
rotated
along a second opposite direction 25, in any position under tension, as better
shown in Figures 6 and 14. When the required torque is reached, as apparent to
a
person skilled in the art, the fasteners 19 are then tightened to block any
movement of the overhead shaft 5 and ensure the normal operation and safety of
the rolling door assembly 3. More specifically, Figure 5 shows the shaft 5
after
having been rotated in a clockwise direction. This rotation forces the cam 15
to
CA 02425108 2003-04-10
rotate in a counterclockwise direction. If the overhead shaft 5, by virtue of
the
tension torque present on the counterbalancing spring, attempts to lower its
torque
by turning counterclockwise, the cam 15 simply rotates clockwise by an amount
sufficient for friction means to interact, such as a knurled portion or teeth
of the
5 surface 23 of the cam 15, as illustrated in Figure 6, engaging the shaft 5
and thus
preventing further rotation thereof.
It is to be understood that several modifications could be made to the
present ratchet-like system 1 according to the present invention without
departing
10 from the scope of the present invention. Indeed, as aforementioned, the
cam{s) 15
may be shaped, positioned, and sized in such a way that the effect of gravity
will
act to replace the biasing force of a spring member 27. Moreover, the
counterbalancing spring may be direct to the shaft 5 but also be installed
directly
on the wall bracket as in the case with commercial garage doors and
residential
15 doors. In such cases, some modifications would have to be made, but the
general
principles of the present ratchet-like system 1 allowing the overhead shaft 5
to be
rotated along one direction 21, but preventing the rotation thereof in a
second
opposite direction 25, will still be possible to use. Moreover, according to
the
present invention, the ratchet-like system 1 may cornprise a plurality of cams
15,
such as a pair of cams 15, as better shown in Figures 7-9. In such case, the
ratchet-like system 1 is preferably devised to be symmetrical, so that either
side
may be used on a corresponding end of the overhead shaft 5. It is also worth
mentioning that the cam 15 may or may not be provided with a teeth to increase
friction between the shaft 5 and the cam 15. Alternatively, as also apparent
to a
person skilled in the art, the cam surface 23 may be provided with other
suitable
friction means for ensuring a proper engagement between the cam 15 and the
overhead shaft 5 when the latter is rotated along the second direction 25.
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 3 or existing door assemblies
3.
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16
In such cases, the present invention is devised to securely control rotation
of the
overhead shaft 5 of the rolling door assembly 3 during winding thereof and
thus
prevent significant damages to property and serious personal injuries to
people.
The present invention is a compact, reliable, easy to use, easy to maintain,
and
cost effective system for winding rolling door assemblies 3. Moreover, the
present
ratchet-like system 1 provides an easier and safer way of winding rolling door
assemblies 3 than what is passible with the devices andlor method available in
the
prior art. Furthermore, the present invention may be used with other kinds of
door
assemblies 3, such as fire doors and/or shutters for example, or with any
other
items provided with a shaft requiring to be properly adjusted, rotation-wise,
as
aforementioned and as apparent to a person skilled in the art.
Of course, numerous modifications could be made to the above
described embodiments without departing the scope of the invention, as defined
in
the appended claims.
