Note: Descriptions are shown in the official language in which they were submitted.
2g3~
~ETHOD AND APPARATUS FOR T~E ASSEMæLY AND
DISASSEMBLY ~F TEfflPORARY STRUCTURES
The present invention relates to b~ilding construction techniques and, in
particular, to a ~ethod and apparatus for the erection and demolition of
temporary structures.
Most construction projects require the erection and demolition of one or
more types of temporary structures for their completion. In order to proceed
efficiently with a construction project, temporary structures rnust be
demoll~hed or quickly a~ possible after the completion of the stage of the
project for which they were required. Examples of temporary structures which
are particularly well adapted for assembly with the apparatus in accordance
wlth the invention are concrete forms, barriers, and temporary scafold
platforms. Such temporary structures have traditionally been assembled using
boards or plywood which are fastened together with planks or similar bracing
and driven fastener3 such as nails. Such temporary structures are
disassembled manually using handtools such as wrecking bars. Thls method is
time consuming and contributes to the safety hazards of the work environment.
It is an object of the present invention to overcome the drawbacks described
above. In accordance with the invention, a method and apparatus is provided
for assembling and rapidly disassembling temporary structures. The apparatus
in accordance with the invention comprises a connector element which includes
an elongated channel having opposed longitudinal coplanar flanges provided
with spaced apart holes adapted to accommodate driven fasteners. The
connector element further includes an elongated inflatable tube which is
placed inside the channel before or after a temporary structure is assembled.
When the temporary structure is to be disasse~bled, the elongated tube is
pressurized so that it expands along it~ length to withdraw the fasteners
driven along the opposed sides of the connector element. Thus, dlsassembly of
the temporary structure ls effected very qulckly, efficiently and safely. The
connector elements are, of course, repeatedly reu~able. Other components of
the temporary structure are also reusable so long as they contlnue to hold
driven fasteners reliably.
The inventlon will now be described by way of example only and with
reference to the appended drawings, wherein:
Fig. 1 is a perspective view of a portion of a platform constructed in
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accordance with the method and apparatus of the invention;
Fig. 2 is a cross-sectional view of the platform of Fig. l: and
Fig. 3 is a cross-sectional view of the disassembly of the platform shown in
Fig. 1.
Figs. 1 and 2 show a platform which may be used, for example, as a concrete
form in which the components, such as the boards 1 which are placed side by
side, are ~oined together hy means of an elongated connector element 2. The
connector element 2 is attached to the boards in a direction transverse to the
longitudlnal dimenslon o~ the boards. As seen in Figs. 1-3, the connector
element 2 is advantageously an elongated profile made of plate-like material
such as sheet iron. The cross-sectional profile of the connector includes a
central channel portion 3 having a general U-shape and, along each side of the
central channel portion 3, flanges 4 having a generally planar form. The
inner surfaces 4' of the flanges 4 face towards the boards 1 which are
attached thereto by means of spikes 5 that project perpendicularly from the
surface 4'. The flanges 4 are substantially coplanar and ~hey are parallel
with the planar bottom of the U-shaped central channel portion 3.
The combination of the boards 1 and the central channel portion 3 of the
connector element 2 define an elongated trapezoidal space in which an
inflatable tube 6 is arranged. The inflatable tube 6 has a narrow elongated
shape and is preferably substantiall~ identical in length to the connector
element. The inflatable tube 6 is closed on each end and at least one end is
provided with a valve or connector for introducing a pressuri~ed fluid into
the tube. The inflatable tube 6 is ~lattened during the assembly of a
temporary construction so that its inner surfaces are ad~acent each other.
The outer surfaces of the inflatable tube contact both the boards 1 and a
filler element 7 which is placed inside the U-shaped central channel portion
3. The purpose of the flller element 7 is to fill the elongated space wlthin
the central channel portion 3 to an extent that the flattened inElatable tube
6 substantially fills the remainder of the space. The cross-section of the
central channel portlon 3 must be constructed so that the connector element 2
has the desired rigidity, especially longitudinal stiffness. This means that
the cross-sectional area of the elongated space i9 in most cases too large for
the inflatable tube to release the connector properly. In order to provide
the required rigidity in the connector element 2 while restricting the space
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required to acco~odate the flattened inflatable tube 6, a filler element 7 is
used. As the opposed ends of the connector element 2 are open, the inflatable
tube 6 and the optional filler element 7 may also be inserted inside the
connector element 2 after the platform has been assembled. 0 course, the
installation of those components may also be effected during conRtruction.
In order to disassemble the platform shown in Fig. 1, the infl~table tube is
filled with a pressurized fluid and the pressure causes the tube to expand,
whereby the connector element 2 is separated from the board9 1, as shown in
Fig. 3. Due to the expansion force 9 which acts against board 1 and the
counterforce 10 which acts against the surface of the filler element 7, the
spikes 5 are withdrawn from the boards 1 and the connector element i9
simultaneously removed from each board.
The inflatable tube 6 is preerably constructed from one of a group of
elastic materials having both sufficient flexibility and good puncture
resistance, one such material being rubber. The walls of the inflatable tube
6 should be tough enough to prevent punctures resulting from contact with
spikes 5, nails or splinters and the like. It is, of course, advantageous
that inflatable tube 6 fill to a substantial extent the elongated space
between the filling element 7 and boards 1, so that loosening of the
attachment between the connector element 2 and the boards l starts immediately
upon the injection of a pressurized fluid into the inflatable tube. It is
further advantageous that the inflatable tube 6 return to a flattened
conditlon when the pressure in the tube is released.
Any fluid medium may be used to inflate the infl~table tube 6. Preferred
mediums are gases such as compressed air, oxygen or carbon dioxide and liquids
such as water or oil. The pressure required for detaching the boards 1 from
the connector element 2 does not have to be too great because of the even
distribution o pressure along the entire length of the connector element.
For instance, in most cases the pressure of a water supply line (40-60 pounds)
is sufficlent to detach the connector element from softwood boards or plywood.
After disassembly o a temporary construction, in most cases the various
parts o the construction may be reused because the parts remain essentially
undamaged during dlsassembly.
For those skilled in the art, it ls apparent that the scope of the invention
should not be limited to the embodiment described hereinbefore. The shape of
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the connector element 2 is not restricted in any way to the U-shape disclosed
in Figs. 1 through 3. The important feature of a connector element 2 is that
it includes a central channel which can accept either directly or indirectly
the counterforce 10 rom an inilatable tube to release the connector 2 from at
least one building component such as a board 1. The connector element may
likewise be straight or curved in its longitudinal dimension. The actual
ad~oinment of the connector element to a building component may be made by
means of the spikes shown in Figs. 1 - 3 which are punched from the material
of the flanges 4 and/or by means of separate nails, or the like which are
driven through holes provided in the flanges 4.
Although the only application herelnbefore described related to the
connection of boards to a connector element 2, the apparatus and method are
equally applicable to any material which accepts and retains driven
fasteners. Thus, in addition to boards, the invention may be used in
con~unction with sheet materials constructed from a wood or plastic base. One
of the most important applications of the apparatus and method is the assembly
of temporary structures used for concrete forms or or barriers, but the
method and apparatus may also be applied to other temporary structures which
must be disassembled once the pro~ect for which they are required is
completed. The requirement for quick disassembly is also evident, for
instance, in army engineering works.
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