Note: Descriptions are shown in the official language in which they were submitted.
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SUSPENDED CABLE SCAFFOLD ASSEMBLY
FIELD OF THE INVENTION
The present invention relates to the field of scaffoldings and more
particularly
s concerns a versatile suspended cable scaffold assembly for use inside a
building
or a vessel, for working on the side of or under a bridge, at the construction
field of
a multi-storied building or the like.
BACKGROUND OF THE INVENTION
~o Conventional scaffoldings are erected by successively assembling pipes and
related components vertically from the ground level up, along the exterior of
a
structure such as a building. With this method, the maximum height of the
scaffolding is limited by physical factors such as weight, installation and
stability,
making any attempt to go beyond a reasonable height too costly to be realized
in
~ s practice. Another disadvantage of the conventional bottom/up method of
setting up
a scaffold is that the resulting structure occupies a lot of space to provide
proper
balance and support to the whole scaffold system, obstructing access to the
building at locations where the scaffold serves no purpose.
2o A solution to the above-mentioned issues is to suspend scaffoldings from
the top
of the building or structure it allows access to. Various hanging scaffolds
designs
are known is the art. For example, FOSTER (U.S. patent Nos. 763,274 and
763,275, both dated June 21, 1904) discloses a scaffold comprising a set of
outriggers, steel cables carried by the outriggers and platforms suitably
supported
2s by the suspending cables. Adjustment possibilities are mentioned, but no
specific
teaching is made in that regard or as to the means to clamp a scaffold to a
building. The possibility of adding levels to the scaffolding is discussed,
but not the
modification of the already mounted scaffold levels. Generally, the structure
taught
by FOSTER seems rudimentary in terms of size and no communication is
3o provided between the different stories.
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Other designs of suspended scaffolds are for example known from U.S. patent
Nos. 1,750,269 (JOHNSTON); 3,700,071 (KIKUCHI); 4,413,707 (LIENHARD Sr.);
and 4,815, 563 (PUCCINELLI et al.).
s Despite the teachings of prior art, there is still a need for a stable,
inexpensive,
semi-permanent, interconnected, multi-levelled, adjustable, light suspended
scaffold assembly.
SUMMARY OF THE INVENTION
~o Accordingly, the present invention provides a suspended scaffold assembly
for
allowing access to a structure. The assembly first includes a plurality of
cables
suspended from an elevated portion of the structure. Each cable has a
plurality of
support members rigidly affixed thereon at regular intervals therealong with a
distance between consecutive support members being selected between 250 mm
~ s and 1000 mm, the support members of neighbouring cables being in alignment
with each other.
The assembly further includes a plurality of beams, each mounted horizontally
between a pair of cables. Each beam has opposite extremities, each provided
with
2o a fastening assembly for fastening this extremity to a respective cable of
the pair
of cables. The fastening assembly is supported by one of the support members
affixed to this respective cable.
The assembly finally includes a plurality of scaffold elements mounted to the
2s beams and positioned so as to allow access to the structure.
In accordance with another aspect of the invention, there is also provided a
suspended scaffolding kit mountable to allow access to a structure. The kit
includes a plurality of cables suspendable from an elevated portion of the
3o structure, each cable having a plurality of support members rigidly affixed
thereon.
The support members are disposed along the cables at regular intervals with a
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distance between consecutive support members being selected between 250 mm
and 1000 mm. A plurality of beams are further provided, each mountable
horizontally between a pair of cables. Each beam has opposite extremities,
each
provided with a fastening assembly for fastening this extremity to a
respective
cable of the pair of cables, in a supported relationship with any one of the
support
members affixed to this respective cable. A plurality of scaffold elements,
mountable to the beams so as to allow access to the structure, is also
provided.
Advantageously, the suspended scaffold of the present invention may be mounted
~o in a limitless number of configurations to allow proper access to a
structure. The
positioning of the support members further allows to easily design and modify
these configurations before and after installation so that at all time access
to the
structure can be optimized.
~s Other features and advantages of the present invention will be better
understood
upon reading of preferred embodiments thereof with reference to the appended
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
2o FIG. 1 is a perspective view of a multi-level scaffold installed on a
structure
according to a preferred embodiment of the invention.
FIG. 2 is a partial perspective view of a multi-level scaffolding according to
a
preferred embodiment of the invention.
FIG. 3 is a partial perspective view of the top of a scaffold according to a
preferred
embodiment of the invention.
FIG. 4 is a partial side view of the top of a scaffold according to a
preferred
3o embodiment of the invention.
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FIG. 5 is a side view of an embodiment of the invention.
FIG. 6 is a detailed side view of an embodiment of the invention.
s FIG. 7 is a sectional top view of an adjustable ring of the invention.
FIG. 8 is a sectional elevation view of an adjustable ring of the invention.
FIG. 9 is a partial elevation view of an embodiment of the invention.
to
FIG. 10 is a partial perspective view of an embodiment of the invention.
FIG. 11 is a partial side view of an embodiment of the present invention.
is FIG. 12 is a partial side view of a cable of the present invention.
FIG. 13 is a partial front view of a cable of the present invention.
FIGs. 14A is a front view of a part of a scaffold assembly according to
another
2o preferred embodiment of the invention; FIG. 14B is a partial side view of
the
scaffold of FIG. 14A; and FIG. 14C is a top view of a cable clamp used in the
embodiment of FIG. 14A.
DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION
2s Referring to FIGs. 1 and 2, there is shown a suspended scaffold assembly 20
according to a preferred embodiment of the present invention. It is understood
throughout the present description that the scaffold of the invention is
intended to
provide access to any appropriate structure, may it be a building or a vessel,
for
working on the side of or under a bridge, at the construction field of a multi-
storied
3o building or any other structure which needs to be accessed by a scaffold
system,
indoors or outdoors. It is a particularly advantageous feature of the present
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invention that it provides great flexibility of design so that it may be
adapted to
structures of a wide variety of shapes and heights.
The scaffold 20 includes a plurality of supporting cables 22. The number of
cables
s in a given assembly may vary and is preferably sufficient to provide the
necessary
access to the structure. The cables are preferably made of threaded steel of
5/8"
of diameter, but could have different dimensions or be made of any
sufficiently
strong material, such as for example nylon, aluminum, stainless steel or even
be
chains of such materials.
~o
The cables 22 are solidly suspended from an elevated portion of the structure.
By
"elevated portion", it is meant that the fastening point of the scaffold to
the
structure is sufficiently high to ensure that the scaffold provides access to
the
areas of the structure which need accessing, and it is understood that this
does
i s not necessarily need to be at the actual top of the structure. Referring
more
particularly to FIG. 3, in the preferred embodiment, outriggers 24 are affixed
to a
counterweight 25 or directly to the structure by any appropriate means such as
bolts, and project horizontally therefrom. The outriggers could for example be
embodied by any I-Beam or beams of rectangular or round hollow sections, etc.
2o The cables 22 are suspended from the outriggers by solid attachment means
such
as eyebolts. In cases where the portion of the structure to which the
outriggers are
mounted is uneven, means may be provided to adjust the length of the cables to
compensate, such as a turnbuckle 23 (see FIG. 4). It is of course understood
that
any other suspension system able to suspend cables from an elevated structure
2s would still fall within the scope of the present invention.
According to a preferred embodiment of the invention, the spacing between the
cables varies from 7' to 10' apart, and the length of the cables is either 50'
or 100'.
Referring to FIGs. 12 and 13, according to another preferred feature of the
present
3o invention, a typical connection between two cables 22 and 22' is shown
attached
end to end by a loop formed at one of their respective extremities, and then
joined
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together by a bolt 21 inserted in the loop of each cable, typically of 1 '/4"
in
diameter and 4 '/2' in length.
Referring to FIG. 5, each cable 22 is provided with a plurality of support
members
s 26, rigidly affixed thereon and disposed at regular intervals along the
cable 22. By
"rigidly affixed", it is understood that the support members 26 are solidly
pre-
installed on the cables 22, before installation of the scaffold assembly, and
are not
removable therefrom. In the preferred embodiment, the support members 26 are
made of steel, have a 2" diameter and are pressed or clamped on the cables 22.
~ o Although the support members are herein shown to be cylindrical, they
could have
a different cross-section, such as rectangular, or be variable along the cable
length.
The distance between consecutive support members 26 is a fixed value selected
is between 250 mm and 1000 mm, and is preferably of about 500 mm. When the
cables 22 are suspended, the support members 26 on a given cable 22 are in
horizontal alignment with the support members 26 of the neighbouring cables
22,
so that it is possible to affix a platform, stairway, guardrail, etc., at
every support
member height. In this manner, all of the support members form a "grid" which
2o serves as the basis for the scaffold design and configuration. This feature
is
particularly advantageous in that it allows the scaffolding to be very
versatile and
adaptable to the needs of a particular job or to structures of various
configuration
or geometry. It also facilitates modifications to these configurations after
installation of the scaffold.
The scaffolding further includes a plurality of beams 36 mounted horizontally
between pairs of neighbouring cables 22. The beams 36 are preferably made of
steel but may be made of any other appropriate rigid material. They may also
be of
a telescopic construction. The opposite extremities of each beam 36 are
provided
3o with fastening assemblies 37 for fastening the corresponding extremity of
the
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beam 36 to a given cable 22, supported by one of the support members 26 on
this
cable 22.
Referring to FIGs. 9 to 11, a fastening assembly 37 according to a preferred
s embodiment is illustrated, the fastening assembly 37 at each extremity of a
given
beam 36 being provided with a pair of parallel transversally projecting arms
38
disposed so as to be supported by the top surface 39 of the corresponding
support
member. The arms 38 may be embodied by any appropriate members such as, for
example, a clip, an H-clip, or an L-shaped metallic pin. The arms 38 are
preferably
io affixed to the corresponding beam by bolts 40. A further bolt 40 is used to
bridge
the space between the arms 38 on the other side of the cable 22 to prevent the
cable 22 from slipping out of the space between the parallel arms. 1n
alternative
embodiments, the arms 38 may be welded to the beam 36 or affixed thereto by
any other appropriate means. It is understood that the above description of a
is fastening assembly is given by way of example and that the beams may be
retained to the cables in any way without departing from the scope of the
present
invention.
The suspended scaffold assembly of the present invention further includes a
2o plurality of scaffold elements mounted to the beams and positioned so as to
allow
access to the structure. The scaffold elements may be embodied by aluminum
platforms, as is well known in the art, or guard ramps or stairways, further
adding
to the versatility of the design. Referring back to FIGs. 1 and 2, there are
shown
two examples of different simple configurations which could be obtained with
the
2s present invention. FIG. 1 shows a series of platforms 42 installed so as to
surround a bridge pillar at four different levels. Guardrails 44 are also
provided. In
the embodiment of FIG. 2, four cables 22 are disposed to form a stairwell in
which
stairways 46 are mounted, allowing workers to travel conveniently from one
platform to another.
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Typically, the guardrails 44 are made of pipes of 'h" or g/" in diameter but
could
also be made of wire rope, nylon, wood, aluminum, pvc or any other appropriate
material. The guardrails 44 may be embodied by the same beams 46 used to
support the platforms and stairways, or may be of a different construction.
The
s support of each platform is preferably made of hollow structural steel (HSS)
of
2"x2" and of a length of 42" along the width of the platform. The platforms
may be
made of metal, wood or plywood, steel, duckboard, aluminum, etc. The platform
attachment means that allow the attachment of the platform to the beams
preferably include '/2' bolts with jam nuts. The stairways may be of any
appropriate
to construction and material and be provided or not with guardrails. Of
course, these
characteristics are given by way of example and are not limitative to the
scope of
the present invention.
Referring to FIGs. 6 to 8 and 14A to 14C, in accordance with another
embodiment
~ s of the present invention the scaffold assembly may be further provided
with
adjustable support members 48 removably affixed to cables 22 at intermediate
positions between the rigidly affixed support members 26 (see FIG. 14A).
Contrary
to the rigidly affixed support members 26, the adjustable support members may
be
added after installation of the scaffolding are preferably used to support
guardrails
20 only. Preferably, the adjustable support members 48 are made of two halves
28
and 30 attached together and around the cable by bolts 32, typically '/2" in
diameter for a steel cable of 5/8" in diameter. The adjustable support members
48
may be provided with a cable clamp 34 supporting it from underneath, as shown
in
FIGs. 6, 14B and 14C. In yet another embodiment, the adjustable support
2s members could be embodied by wire clips or disks such as typically found in
standard scaffoldings for fastening components together.
The present invention therefore provides a versatile scaffold assembly which
is
easy to install for one skilled in the art and may provide convenient access
to an
3o elevated structure. In a previous realisation of an embodiment of the
invention, it
was surprisingly possible to mount a forty-five-level suspended scaffold
without
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difficulty, the overall structure being very stable, and relatively
inexpensive.
Conveniently, the overall structure may be covered with a hood (not shown)
attached thereto, made for example out of plastic or strong cloth, that would
allow
workers to stay on the structure independently of bad weather or the period of
the
s year.
Advantageously, the cables with the pre-affixed support members, beams, and
scaffold elements of the present invention may be sold in the form of a kit,
which
the user may install according to his particular needs. The accompanying
to mounting components may or may not be included as part of the kit.
Of course numerous modifications could be made to the embodiments described
above without departing from the scope of the invention as defined in the
appended claims.
~s
