Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 02501808 2005-03-22
TITLE
PRE-CAST CONCRETE CONSTRUCTION BLOCK WITH
MANIPULATION HANDLES AND METHOD OF PRODUCTION.
BACKGROUND OF THE INVENTION
The modern construction environment and growing requirements for
workplace safety and workload limits are becoming increasingly
inconsistent with the standardized pre-cast-concrete building block. This
prior art block is of generally rectangular outline and includes a trio of
l0 webs connecting the inner and outer faces. Modern construction is also
tending towards high-speed operations which limit construction time and
take advantage of just-in time availability of labour and materials. The
individual standard pre-cast standard block remains awkward and overly
heavy for manual work particularly at high rates of construction speed.
The construction worker is required to handle these heavy blocks
increasingly rapidly and over obstacles and other hindrances. Solutions
are apparent which require automation of the delivery and setup operation
within the construction site but such machinery is capital intensive,
cumbersome and difficult to use. Consequently residential construction
2o is tending to prefer poured-in-place foundations despite the tendency of
such foundations to structural cracks and the difficulty in effecting repairs
despite the relative inflexibility of such approaches.
Efforts have been directed towards automated handling machines which
are extremely expensive, require skilled labour for installation, operation
and use and also towards lighter materials which are inappropriate for
many building types and conditions.
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Many builders prefer a pre-cast concrete block foundation and rely upon
a ready supply of inventory standard blocks for successful construction.
Such inventory allows supplies to build at a consistent or determined rate
3o and achieve economies of operation and, thus, acceptable prices.
STATEMENT OF INVENTION
According to the present invention, a pre-cast-concrete building block is
provided which conveniently provides a building element readily used on
a building site which is both lighter in weight and considerably less
35 stressful to manipulate to the site of use, in setup and in installation in
either a 3-web or a 2-web configuration. Its strength is not
compromised and the block may be readily and rapidly formed on
conventional concrete block forming machinery.
Additionally, the invention provides a method of manufacture of pre-cast
40 blocks in either a 3-web or a 2-web configuration including means for
ready and efficient handling.
In particular, the invention provides a pre-cast symmetrical concrete
construction block of generally rectangular outline with an upper and a
lower surface, a pair of opposing generally planar spaced-apart first webs
45 adapted to support a structure and provide an interior and an exterior
foundation or wall surface, a plurality of spaced-apart transverse webs
interconnecting said first webs extending from said lower to said upper
surface and providing at least one void between said first webs, wherein
a pair of said transverse webs are spaced in from a respective end
50 extremity of said block, and wherein said pair of said transverse webs
include lifting means adjacent said upper surface.
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The invention also provides a handle laterally extending from said
transverse web, and, in another embodiment, a handle void in said
transverse web, adjacent the upper surface of the block.
55 A method of production of pre-cast symmetrical concrete construction
blocks of generally rectangular outline is also provided comprising the
steps of providing a two-part cavity mold, including a base portion and a
shaped mold portion, with a generally T-shaped core adjacent said base
portion, filling said mold, allowing said concrete to partially or
60 completely set up, removing said core laterally from said mold, removing
said shaped portion, and removing said setup concrete block from said
base for further cure.
DRAWINGS
In the drawings, like element designations refer to like parts throughout,
65 and:
Figure 1 provides a pictorial view of a standard 3-web pre-cast-concrete
construction block showing the standard configuration and the extended
handle of an embodiment of the invention.
Figure 2 is a cross-section of the block of Figure I taken along line A-A'
70 in Figure 1.
Figure 3 is a similar view to that of Figure 2 including a variation in the
handle of Figure 1.
Figures 4 and 5 are a plan view and an elevation of the block of Figure 3.
Figure 6 is a pictorial view of the preferred embodiment of the invention
75 in a 2-web pre-cast-concrete block.
Figure 7 is a cross-section of the block of Figure 6 taken along line B-B'
in Figure 6.
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Figure 8 is an end elevation of the block of Figure 6.
Figure 9 shows a T-shaped core section adjacent a cavity mold base plate.
80 Figure 10 shows a 2-web configuration of the block of Figure 1.
PREFERRED EMBODIMENTS
As illustrated herein, the invention may be practiced in accordance with a
first embodiment of Fig. 1.
The building block in accordance with the subject invention is generally
85 identified by the reference numeral 1. It comprises a pair of planar
vertical surfaces 2 which typically form the spaced-apart inner and outer
walls of the structure being built. Outer surfaces 2 are connected by 3
transverse webs as at 17. Upper and lower block surfaces 3 and 4 extend
between outer surfaces 2 respectively and provide the structural bearing
90 surfaces.
Webs 17 are spaced apart and provide internal voids as at 5 and 6 in
Figure 1 and are stepped in from the lateral extremities of block 1 at each
end as at 7 and 8.
In Figure I is shown a typical block construction at the left extremity of
95 block 1 and an embodiment of the invention as at handle 9 at the right
extremity. The complete embodiment would include handle 9 at end
lateral end of block 1 for balanced lifting adjacent vertical web extension
12' .
Later step 8 includes lateral vertical surfaces 10 and 11, inset surface 8a
100 and web extensions as at 12 in Figure 1.
Handle 9 is integrally formed with and into lateral web 17 during casting
and includes horizontal surface 13, generally vertical surface 14, inclined
surface 15.
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Preferably, surface 13 is formed into and provides an extension of block
105 upper surface 3.
Further preferably, inclined surface 15 provides a gripping surface for
manual or other lifting of the finished block and its installation at a
construction site. Further, since the block 1 would typically be formed in
an inverse mold, inclined surface 15 would provide for plastic flow of
0 molding material into a corresponding mold cavity so as to effectively
form handle 9.
Handle 9 may include gaps 16 between it and the vertical surface 12 as
shown in Figure 1.
In Figure 2 a cross-section of block 1 taken along line A-A' in Figure 1 is
115 shown.
In Figure 3 another embodiment of block 1 is shown in cross-section.
Handle 9' extends laterally to the edge of block 1 with enlarged surfaces
at 13' and 15' so that vertical surface 14' is aligned with vertical surfaces
and 11.
12o Figures 4 and 5 show a plan view and an elevation of the block 1
embodiment of Figure 3. Handle 9b' is formed at the opposite lateral
extremity of block 1 in the same form as handle 9a'.
In the preferred embodiment shown in Figures 6 through 8 the 3-web 17
design of Figures 1 through 5 is replaced with a 2-web design for further
125 ease in manufacture and handling.
In this embodiment the handle 9" (Figure 8) is formed integrally with the
upper surface 3 of webs 17. Each web 17 is provided with a pair of co-
operating cantilever sections as at 18 so as to form a gap 24. Opposing
vertical surfaces 19, outwardly inclined surfaces 20 and further vertical
130 surfaces 21 provide for an enlarged opening in the web suitable for a
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workman's hands or automated equipment. The gap is closed by
horizontally extending surface 22 spaced from upper surface 3.
Inclined surfaces 21 provide for smooth and ready casting of the block 1
in high-speed operations in an inverted mold (as with the block of Figures
135 1 through 5) and lifting surfaces 20 in the resulting block.
Due to the instep provided by surfaces 12 and the handle 9" a workman's
hands or other equipment may carry and place the blocks of Figure 6
through 8 in rapid and abutting succession during construction of a
foundation wall or other structure in a known manner.
140 In Figure 7 is shown a cross-section of the block of Figure 6 taken along
line B-B' which shows the extended central void 23 between webs 17.
In Figure 8 is shown an end elevation of the block of Figure 6 which
shows the load bearing inclined surfaces 20 and the gap 24 of handle 9" .
In manufacture, the handle 9" of Figure 8 may be formed by plastic flow
145 of molding material around a removable generally T-shaped insert in the
shape of handle 9" as at 25 in Figure 9. The insert 25 would bear upon
the base 26 of an inverted mold (not shown) and allow for compressive
and vibration stresses on the molding material for completion of the
cavity filling operation, settlement, removal and setting up, along with the
150 various handling operations required for high-speed molding operations.
After setting up the insert would be withdrawn laterally from the mold
prior to the extraction of the partially set and dimensionally stable block.
Figure 10 shows a 2-web configuration of the standard 3-web block of
Figure 1. In Figure 10 the block is shown with a handle of the present
155 invention at one lateral extremity which would be repeated (not shown) at
the other lateral extremity for a typical pair. Webs 17' a and 17' b
would be inset from the lateral ends of the block 1 by a greater amount as
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at 7 and 8 than would be typical of the 3-web block of Figure 1. Only a
single internal void 5' would be formed thereby making the block
160 considerably lighter in overall weight, easier to manipulate and less
likely
to fracture upon impact due to its reduced mass. The larger inset as at 8
would provide capacity for a varying width of handle and a variable
extent and slope for inclined surface 15.
The present invention includes a preferred method of molding of a pre-
165 cast concrete construction block including the steps of preparing an
inverted mold having at least 2 web spaces providing at least 1 void and
lateral insteps, providing a generally T-shaped core insert 25 extending
laterally along the base 26 of the mold inverted so as to bear upon the
narrow portion of the T as at 27 and including generally inclined surfaces
170 28 so as to facilitate plastic flow of molding material or concrete in a
high-speed manufacturing operation, adding concrete casting material to
the mold cavity, ensuring cavity fill with vibration or other compaction
means, setting up the casting material, lateral withdrawal of the insert 25,
removal of the mold and curing the finished product.
175 Although the preferred embodiments of the invention have been
illustrated and described herein, it is intended to be understood by those
skilled in the art that various modifications and omissions in form and
detail may be made without departing from the spirit and scope of the
invention as defined by the following claims.
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