Note: Descriptions are shown in the official language in which they were submitted.
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BLOCK SPLITTING ASSEMBLY AND METHOD
This application is being filed as a PCT international patent
application in the name of Anchor Wall Systems, Inc., a U.S. national
corporation,
on 19 October 2001, designating all countries except the U.S.
Field of the Invention
The invention relates generally to manufacture of masonry block.
More specifically, it relates to equipment and processes for the creation of
decorative faces on masonry block. Even more specifically, the invention
relates to
equipment and processes for producing irregular textures and the appearance of
weathered or rock-like edges on masonry block, as well as to masonry blocks
that
result from such equipment and processes.
Background of the Invention
It has become rather common to use concrete masonry blocks for
landscaping purposes. Such blocks are used to create, for example, retaining
walls,
ranging from comparatively large structures to small tree ring walls and
garden
edging walls. Concrete masonry blocks are made in high speed production
plants,
and typically are exceedingly uniform in appearance. This is not an
undesirable
characteristic in some landscaping applications, but it is a drawback in many
applications where there is a demand for a "natural" appearance to the
material used
to construct the walls and other landscaping structures.
One way to make concrete masonry blocks less uniform, and more
"natural" appearing, is to use a splitting process to create a "rock-face" on
the block.
In this process, as it is commonly practiced, a large concrete workpiece which
has
been adequately cured is split or cracked apart to form two blocks. The
resulting
faces of the resulting two blocks along the plane of splitting or cracking are
textured
and irregular, so as to appear °°rock-like". This process of
splitting a workpiece into
two masonry blocks to create a rock-like appearance on the exposed faces of
the
blocks is shown, for example, in Besser's U.S. Patent No. 1,534,353, which
discloses
the manual splitting of blocks using a hammer and chisel.
Automated equipment to split block is well-known, and generally
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includes splitting apparatus comprising a supporting table and opposed,
hydraulically-actuated splitting blades. A splitting blade in this application
is
typically a substantial steel plate that is tapered to a relatively narrow or
sharp knife
edge. The blades typically are arranged so that the knife edges will engage
the top
and bottom surfaces of the workpiece in a perpendicular relationship with
those
surfaces, and arranged in a coplanar relationship with each other. In
operation, the
workpiece is moved onto the supporting table and between the blades. The
blades
are brought into engagement with the top and bottom surfaces of the workpiece.
An
increasing force is exerted on each blade, urging the blades towards each
other. As
the forces on the blades are increased, the workpiece splits (cracks),
generally along
the plane of alignment of the blades.
These machines are useful for the high-speed processing of blocks.
They produce a rock-face finish on the blocks. No two faces resulting from
this
process are identical, so the blocks are more natural in appearance than
standard,
non-split blocks. However, the edges of the faces resulting from the industry-
standard splitting process are generally well-defined, i.e., regular and
"sharp", and
the non-split surfaces of the blocks, which are sometimes in view in landscape
applications, are regular, "shiny" and non-textured, and have a "machine-made"
appearance.
These concrete masonry blocks can be made to look more natural if
the regular, sharp edges of their faces are eliminated.
One known process for eliminating the regular, sharp edges on
concrete blocks is the process known as tumbling. In this process, a
relatively large
number of blocks are loaded into a drum which is rotated around a generally
horizontal axis. The blocks bang against each other, knocking off the sharp
edges,
and also chipping and scarring the edges and faces of the blocks. The process
has
been commonly used to produce a weathered, "used" look to concrete paving
stones.
These paving stones are typically relatively small blocks of concrete. A
common
size is 3 3/a inches wide by 7 3/a. inches long by 2 ~/2 inches thick, with a
weight of
about 6 pounds.
The tumbling process is also now being used with some retaining
wall blocks to produce a weathered, less uniform look to the faces of the
blocks.
There are several drawbacks to the use of the tumbling process in general, and
to the
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tumbling of retaining wall blocks, in particular. In general, tumbling is a
costly
process. The blocks must be very strong before they can be tumbled. Typically,
the
blocks must sit for several weeks after they have been formed to gain adequate
strength. This means they must be assembled into cubes, typically on wooden
pallets, and transported away from the production line for the necessary
storage
time. They must then be transported to the tumbler, depalletized, processed
through
the tumbler, and recubed and repalletized. All of this "off line" processing
is
expensive. Additionally, there can be substantial spoilage of blocks that
break apart
in the tumbler. The tumbling apparatus itself can be quite expensive, and a
high
maintenance item.
Retaining wall blocks, unlike payers, can have relatively complex
shapes. They are stacked into courses in use, with each course setback a
uniform
distance from the course below. Retaining walls must also typically have some
sheax strength between courses, to resist earth pressures behind the wall. A
common
way to provide uniform setback and course-to-course shear strength is to form
an
integral locator/shear key on the blocks. Commonly these keys take the form of
lips
(flanges) or tongue and groove structures. Because retaining wall blocks range
in
size from quite small blocks (e.g. about 10 pounds and having a front face
with an
area of about'/a square foot) up to quite large blocks having a front face of
a full
square foot and weighing on the order of one hundred pounds, they may also be
cored, or have extended tail sections. These complex shapes cannot survive the
tumbling process. Locators get knocked off, and face shells get cracked
through.
As a consequence, the retaining wall blocks that do get tumbled are typically
of very
simple shapes, are relatively small, and do not have integral locator/shear
keys.
Instead, they must be used with ancillary pins, clips, or other devices to
establish
setback and shear resistance. Use of these ancillary pins or clips makes it
more
difficult and expensive to construct walls than is the case with blocks having
integral
locators.
Another option for eliminating the sharp, regular edges and for
distressing the face of concrete blocks is to use a hammermill-type machine.
In this
type of machine, rotating hammers or other tools attack the face of the block
to chip
away pieces of it. These types of machines are typically expensive, and
require
space on the production line that is often not available in block plants,
especially
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older plants. This option can also slow down production, if it is done "in
line",
because the process can only move as fast as the hamrnermill can operate on
each
bloclc, and the blocks typically need to be manipulated, e.g. flipped over
and/or
rotated, to attack all of their edges. If the hammermill-type process is done
off line,
it creates many of the inefficiencies described above with respect to
tumbling.
Accordingly, there is a need for equipment and a process that creates
a more natural appearance to the faces of concrete retaining wall blocks, by,
among
other things, eliminating the regular, sharp face edges that result from the
industry-
standard splitting process, particularly, in such a manner that it does not
slow down
the production line, does not add costly equipment to the line, does not
require
additional space on a production line, is not labor-intensive, and does not
have high
cull rates when processing blocks with integral locator flanges or other
similar
features.
Summary of the Invention
In accordance with a first aspect of the invention, there is provided a
masonry block that results from a splitting operation on a molded workpiece by
at
least one splitting assembly in a block splitter having a splitting line. The
at least
one splitting assembly includes a plurality of proj ections disposed on at
least one
side of the splitting line and positioned to engage the workpiece during the
splitting
operation. The resulting masonry block comprises a block body including a top
surface, a bottom surface, a front surface extending between the top and
bottom
surfaces, a rear surface extending between the top and bottom surfaces, and
side
surfaces between the front and rear surfaces. In addition, the block includes
a
locator protrusion formed integrally with the block and disposed on the top or
bottom surface thereof. The intersection of the front surface and the top
surface
defines an upper edge, and the intersection of the front surface and the
bottom
surface defines a lower edge, and the front surface and at least a portion of
one of
the upper edge and the lower edge are irregular as a result of the plurality
of
projections engaging the workpiece during the splitting operation.
In the preferred embodiment, the locator protrusion is preferably
disposed on the bottom surface. The irregular edge portion of the block is
distressed
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so as to not appear as sharp with well-defined, regular edges, but, rather, to
appear to
have been weathered, tumbled, or otherwise broken, irregular and worn.
In accordance with a second aspect of the invention, there is provided
a wall that is formed from a plurality of the masonry blocks.
In accordance with another aspect of the invention, there is provided
a masonry block formed from a molded workpiece. The masonry block comprises a
block body that includes a top surface, a bottom surface, a front surface
extending
between the top and bottom surfaces, a rear surface extending between the top
and
bottom surfaces, and side surfaces between the front and rear surfaces. A
portion of
at least one of the surfaces is textured as a result of at least one channel
provided in a
wall of the workpiece-forming mold.
In another aspect of the invention, a masonry block is provided that is
produced from a molded workpiece that is split in a block splitter having a
splitting
line. The block splitter comprises a first splitting assembly that includes a
plurality
of projections disposed on at least one side of the splitting line. The
projections are
positioned so that they engage the workpiece during the splitting operation,
whereby
the masonry block includes at least one irregular split edge and surface
produced by
the first splitting assembly.
In accordance with another aspect of the invention, a method of
producing a masonry block having at least one irregular split edge and surface
is
provided. The method comprises providing a masonry block sputter having a
splitting line with which a masonry workpiece to be split is to be aligned,
with the
block splitter including a first splitting assembly that includes a plurality
of
projections disposed on at least one side of the splitting line. The
projections are
positioned so that they engage the workpiece during the splitting operation. A
masonry workpiece is located in the masonry block splitter so that the
workpiece is
aligned with the splitting line, and the workpiece is split into at least two
pieces
using the splitting assembly.
In another aspect of the invention, a masonry block is provided
having at Ieast one irregular split edge and surface that is produced when a
molded
workpiece is split in a block splitter comprising a first splitting blade
assembly
having a first splitting blade connected to a first blade holder. The first
blade holder
includes a blade holder surface extending away from the first splitting blade
on at
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least one side thereof. The blade holder surface is disposed at an acute angle
relative
to horizontal, and the blade holder surface is engageable with the workpiece
during
the splitting operation. The irregular split edge and surface is at least
partially the
result of the contact of the blade holder surface with the workpiece.
In still another aspect of the invention, a splitting assembly for use in
a block splitter is provided. The splitting assembly comprises a splitting
blade, and
a plurality ofprojections positioned adjacent to the splitting blade on at
least one
side thereof. The projections and the blade are fixed relative to each other
during a
splitting operation whereby the projections and the blade move simultaneously
during the splitting operation.
In still another aspect of the invention, a mold for producing at least
one masonry unit with a texture on at least one surface is characterized by a
plurality
of side walls defining a mold cavity open at its top and bottom to allow
masonry fill
material to be introduced into the mold cavity by way of its open top and to
discharge molded fill material in the form of a molded masonry unit by way of
its
open bottom. At least one surface texturing channel is formed in the face of
at least
one the side walls of the mold, with the channel extending across the face of
the side
wall in a direction not parallel to the direction of stripping of the mold.
The channel
has a height of less than about 0.75 inches and a depth of less than about
0.50
inches, and at least a portion of the channel is spaced from the top of the
wall in
which it is formed by a distance that is more than about 40% of the distance
from the
top of the side wall to the bottom of the side wall. In addition, a ratio of
the total
projected area of the side wall provided with the channel to the total
projected area
of all channels is more than about 2:1.
In still another aspect of the invention, a masonry block splitter
having a splitting line with which a workpiece is aligned for splitting the
workpiece
into at least two pieces is provided. The block splitter comprises a first
splitting
assembly that includes a plurality of proj ections disposed on at least one
side of the
splitting line. The projections are positioned so that they travel into the
workpiece
as it is split into the at least two pieces by the block splitter, whereby the
first
splitting assembly contributes to the formation of at least one irregular
split edge and
surface on at least one of the split pieces.
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These and various other advantages and features of novelty which
characterize the invention are pointed out with particularity in the claims
annexed
hereto and forming a part hereof. However, for a better understanding of the
invention, its advantages and objects obtained by its use, reference should be
made
to the drawings which form a further part hereof, and to the accompanying
description, in which there is described a preferred embodiment of the
invention.
Brief Description of the Drawings
Figure 1 is a partial perspective view of a block splitting machine
using the block sputter blade assembly of the invention.
Figure 2A is a top plan view of one portion of a splitting blade
assembly in accordance with the invention.
Figure 2B is a top plan view of one portion of a splitting blade
assembly also showing projections of various diameters positioned in a random
manner.
Figure 2C is a top plan view of one portion of a splitting blade
assembly in accordance with a further alternative embodiment of the invention
comprising projections which are random connected and unconnected panels.
Figure 3 is a side elevational view of an alternative embodiment of a
projection in accordance with the invention.
Figure 4A is a side elevational view of a further alternative
embodiment of a projection in accordance with the invention.
Figure 4B is a side elevational view of another alternative
embodiment of the invention depicting projections of varying heights.
Figure 5 is a perspective view of a split workpiece (forming two
masonry blocks), which was split using the sputter blade assembly of the
invention.
Figure 6 is a top plan view of a masonry block split using the splitter
blade assembly of the invention.
Figure 7 is a front elevational view of the masonry block depicted in
Figure 6.
Figure ~ is a partially sectioned end view of an alternative
embodiment of a top splitter blade assembly.
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Figure 9 is a partially sectioned end view of an alternative
embodiment of a bottom splitter blade assembly.
Figure 10 is a top plan view of a portion of the bottom splitter blade
assembly of Figure 9 with one arrangement of projections, shown in relation to
a
workpiece.
Figure 11 is a partially sectioned end view of another alternative
embodiment of a bottom splitter blade assembly.
Figure 12 is a top plan view of a gripper assembly according to the
present invention and a portion of the bottom splitter blade assembly of
Figure 11
with another arrangement of projections, shown in relation to a workpiece.
Figure 12A is an exploded view of the portion contained within Iine
12A in Figure 12.
Figure 13 is a top view of a mold assembly for forming the
workpiece illustrated in Figure 12.
Figure 14 is a perspective view of a masonry block that is split from a
workpiece using top and bottom splitting blade assemblies of the type
illustrated in
Figures 8 and 1 I.
Figure 15 is a bottom plan view of the masonry block in Figure 14.
Figure 16 is a side view of the masonry block of Figure 14.
Figure 17 is a perspective view of an alternative embodiment of a
masonry block that has been split according to the present invention.
Figure 18 illustrates a wall constructed from differently sized bloclcs
that have been split according to the invention.
Figure 19 is a front view of a mold wall in which a single horizontal
groove or channel has been cut in the wall close to the bottom of the wall.
Figure 20 is a sectional view of the mold wall shown in Figure 19
taken at line 20-20 to show the cross section of the groove.
Figure 21 is a top view of a hopper and partition plate for swirling the
colors of the fill material.
Figure 22 is a front view of a mold wall in which multiple shallow
diagonal grooves or channels have been cut in the wall at an angle to the
horizontal.
Figure 22A is a sectional view of the mold wall shown in Figure 22
taken at line 22A-22A to show the cross section of the grooves.
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Figure 23 is a front view of a mold wall in which a single horizontal
groove or channel has been cut in the wall close to the bottom of the wall.
Figure 23A is a sectional view of the mold wall shown in Figure 23
taken at line 23A-23A to show the cross section of the groove.
Figure 24 is a front view of a mold wall in which multiple, shallow,
diagonal grooves or channels have been cut in the wall at an angle to the
horizontal
of about 45 degrees to provide a "criss-cross" pattern.
Figure 25 is a sectional view of a mold wall showing the cross
section of multiple horizontal grooves or channels cut in the mold wall,
extending
from near the bottom of the mold wall to near the top of the mold wall.
Figure 26 is a sectional view of a mold wall showing the cross
section of a v-shaped groove.
Figure 27 is a front view of a wall of a mold in which a serpentine
groove or channel has been cut.
Detailed Description of the Preferred Embodiment
Attention is now directed to the figures where like parts are identified
with like numerals through several views. In Figure 1, a conventional block
splitting machine modified in accordance with the invention is depicted, in
part,
showing in particular the block splitter assembly 10. Generally, block
splitting
machines suitable for practicing the present invention may be obtained from
Lithibar
Co., located in Holland, Michigan and other equipment manufacturers. In
particular,
the Lithibar Co. model 6386 was used in practicing the invention. The block
sputter
assembly 10 generally comprises a support table 11, and opposed first 12 and
second
22 splitting blade assemblies. The first splitting blade assembly 12 is
positioned at
the bottom of the block splitter 10 and, as depicted, includes a splitting
blade 14
projecting from a blade holder 15 and a number of projections 16 positioned on
the
blade holder 15 on either side of and adjacent to the blade. In this case, the
proj ections 16 are generally cylindrically-shaped pieces of steel, having
rounded or
bullet-shaped distal ends. The first splitting blade assembly 12 is adapted to
move
upwardly through an opening in the support table 11 to engage the workpiece
40,
and to move downwardly through the opening so that a subsequent workpiece can
be
positioned in the splitter.
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The invention may be used with any variety of blocks molded or
formed through any variety of processes including those blocks and processes
disclosed in U.S. Patent No. 5,827,015 issued October 27, 1998, U.S. Patent
No.
5,017,049 issued May 21, 1991 and U.S. Patent No. 5,709,062 issued January 20,
1998.
An upper or second splitting blade assembly 22 may also be seen in
Figure 1. The second splitting blade assembly 22 also includes a splitting
blade 24
and a plurality of projections 26 located on either side of the blade 24. The
second
splitting blade assembly may be attached to the machine's top plate 30 through
a
blade holder 28. The position of the workpiece 40, (shown in phantom), within
the
block splitter may be seen in Figure 1, in the ready-to-split position.
As can be seen in Figure 2A, the splitting blade assembly 12 is
generally comprised of a number of projections 16 positioned adjacent to the
blade
14 and on either side of the blade 14. As shown, the proj ections 16 on the
first side
of the blade are staggered in relationship to the projections 16' on the
second side of
the blade. The projections on either side of the blade may also be aligned
depending
upon the intent of the operator.
As can be seen in Figure 2B, the projections 16 may be used without
a splitting blade. The projections 16 may also be varied in diameter or
perimeter, (if
not round), and placed randomly on the splitting assembly 12. Any number of
ordered or random patterns of proj ections 16 may be created using regular or
irregular spacing depending on the effect to be created in the split block.
Figure 2C shows a further alternative embodiment of the invention
where plates 16" are attached to either, or both, assemblies 12 and 22. As can
be
seen, these plates may be configured in random order and left unconnected
across
the surface of the assembly 12. The invention has been practiced using steel
plates
about four inches long welded to the assembly to provide a number of partially
connected projections 16" about two inches high.
In splitting assemblies in which splitting blades are used, such as the
splitting blades 14, 24, the splitting blades are arranged in coplanar
relationship, and
so as to engage the bottom and top surfaces of the workpiece 40 in a generally
perpendicular relationship. The splitting blade 14 (and likewise the splitting
blade
24) define a splitting line SL, shown in Figure 2A, with which the workpiece
40 is
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aligned for splitting. When splitting blades are not used, such as shown in
Figure
2B, the workpiece 40 is still aligned with the splitting line SL which is
illustrated as
extending generally through the center of the assembly 12. In either event,
block
splitters conventionally have a splitting line SL, defined by splitting blades
when
used, with which the workpiece is aligned for splitting.
As shown in Figures 1, 2A and 2B, the proj ections 16 and 16' may
have a rounded shape. However, the shape of the projections may also be
pyramidal, cubic, or pointed with one or more points on the top surface of the
projection. In Figures 2A, 2B and 2C, the relative position of the workpiece
40 is
shown again in phantom outline.
Generally, the projections may have a diameter of about 1/2 to about 1
1/4 inches and may be attached to the blade assembly by welding, screwing or
other
suitable means. The height of the projections may be about 1 ~/a inches and
varied
about 3/a. of an inch shorter or taller depending upon the affect to be
created in the
block at splitting. Attaching the protrusions by threading or screwing, see
Figures 8-
9 and 11, allows easy adjustment of projection height.
The relative height of the proj ection and blade may also be varied
depending upon the effect that is to be created in the block that is split
from a
workpiece according to the invention. Specifically, as can be seen in Figure 3
the
relative height of the blade 14 may be less than the relative height of the
proj ection
16. Alternatively, as can be seen in Figure 4A the relative height of the
blade 24
may be greater than the height of the projections 26. For example, we have
found
with the first splitting blade assembly 12 that X may range from about 1/8 to
about
3/8 of an inch below or beyond the first blade 14. With regard to the second
splitting blade assembly 22, X' may range from about 1/16 to about 1/8 of an
inch
beyond the height of the plurality of the proj ections 26.
Projections 16 such as those depicted in Fig. 2A have been found
useful having a diameter of about l and 1/4 inches and, when used with a blade
14,
having a height of about 1/8 of an inch below the blade in the first or lower
assembly
12 and about 1/8 of an inch below the blade 24 in the second or upper assembly
22.
Overall, the height of the projections on either the lower assembly 12 or
upper
assembly 22 may vary up or down as much as about 3/8 of an inch relative to
the
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height of the blade in either direction relative to the top of the blade, with
the top of
the blade being zero.
In operation, the workpiece 40 is generally centered in the block
splitter and aligned with the splitting line SL according to known practices
as seen in
Figures 1 and 2A, B and C. The block splitter is then activated resulting in
the first
and second opposing splitting blade assemblies 12, 22 converging on, and
striking,
the workpiece 40. In operation, the first and second splitting blade
assemblies may
travel anywhere from about 1/4 to about one inch into the top and bottom
surfaces of
the workpiece. The workpiece 40 is then split resulting in an uneven or
irregular
patterning on the split edges 46a, 46b and 46a', 46b' of the respective
resulting
blocks 42 and 44, as illustrated in Figure 5. As depicted, the workpiece 40 is
split in
two. However, it is possible and within the scope of the invention to split
the
workpiece into more than two pieces. It is also possible and within the scope
of the
invention to split the workpiece into a usable masonry block and a waste
piece.
The distance traveled by the projections 16, 26 into the workpiece
may be varied by adjusting the limit switches on the block splitting machine
and, in
turn, varying the hydraulic pressure with which the splitting assemblies act.
Generally, the splitting assemblies act on the block with a pressure ranging
from
about 600 to about 1000 psi, and preferably about 750 to about 800 psi.
As will be well understood by one of skill in the art, the splitting
machine may include opposed hydraulically activated side knife assemblies (not
shown) which impinge upon the block with the same timing and in the same
manner
as the opposed top and bottom assemblies. Projections 16, 26 may also be used
to
supplement or replace the action of the side knives, as discussed below with
respect
to Figure 12. For example, side knives similar to the upper splitting blade 24
shown
in Figure 8 can be employed.
Closer examination of block 44 after splitting (see Figures 6 and 7)
shows the formation of exaggerated points of erosion in the front, split,
irregular
surface 47 of the block 44. With the block 44 depicted, both the first and
second
blade assemblies 12 and 22 comprised projections 16 and 26, respectively. As a
result, depressions 48 and 50 were formed at the upper and lower edges 46a,
46b of
the front, split surface 47 of the block 44, at the intersection with the
upper 52 and
lower 54 respective surfaces of the block 44.
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The magnitude of the indentations, 48 and 50, or points of erosion is
far greater than that which is caused by conventional splitting blades and may
be
varied by varying the prominence of the projections 16 and 26, (height and
size),
relative to the height and thickness of the blade. In one embodiment of the
invention, masonry block may be split with only a row or rows of projections
16 and
26 without a blade I4 and 24.
Referring to Figures 8 and 9, alternative embodiments of a top
splitting blade assembly 22' and bottom splitting blade assembly 12',
respectively,
are shown. It has been found that more massive blade assemblies 12', 22'
having
projections 16, 26 thereon create a more desirable block face appearance.
Blade
assemblies 12,' 22' include blade holders 15', 28' having blades 14', 24' that
include
central cutting edges 21, 31, respectively. The blade holders 15', 28' include
surfaces 19, 29 extending outwardly from the blades 14', 24'. The cutting
edges 21,
31 define the splitting line along which the workpiece will be split. Surfaces
19, 29
extend away from the blades 14', 24' at relatively shallow angles, so that, as
the
blade assemblies converge during splitting, the surfaces 19, 29 will engage
the split
edges of the workpiece. This engagement breaks, chips, distresses, or softens
the
split edges in an irregular fashion, and the distressing action can be
enhanced by
placing projections on the surfaces 19, 29, as desired. The surfaces 19, 29
are
preferably at an angle a between about 0° and about 30° relative
to horizontal, most
preferably about 23°.
Blade assemblies 12', 22' include projections 16, 26 that are
adjustable and removable. In this way, the same blade assembly can be used for
splitting different block configurations by changing the number, location,
spacing
and height of the projections. Projections 16, 26 are preferably threaded into
corresponding threaded openings 17, 27 for adjustment, although other height
adjustment means could be employed. However, during a splitting action, the
proj ections, the blades and the blade holders are in a fixed relationship
relative to
each other, whereby as the blade holder moves, the projections associated with
the
blade and blade holder move simultaneously therewith.
The projections 16, 26 in this embodiment are preferably made of a
carbide tipped metal material. In addition, the top surface of the projections
16, 26
is jagged, comprising many pyramids in a checkerboard pattern. Projections
such as
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these can be obtained from Fairlane Products Co. of Fraser, Michigan. It will
be
understood that a variety of other projection top surface configurations could
be
employed. The height of the top surface of the projections is preferably a
distance
X' below the cutting edge 21, 31 of the blades 14', 24', most preferably 0.040
inch
below. As discussed above with respect to other embodiments, the projections
may
extend further below, or some distance above, the top of the blade, within the
principles of the invention. The projections shown are about 3/4 inch diameter
with
a 10 thread/inch pitch, and are about 1.50 inches Long. Diameters between
about
0.50 and about 1.0 inch are believed preferable. The loose block material from
the
splitting process entering the threads, in combination with the vertical force
of the
splitting strikes, are considered sufficient to lock the projections in place.
However,
other mechanisms could be used to lock the projections in place relative to
the
blades during the splitting process.
As should be apparent from the description, the blades 14', 24' and
the proj ections 16, 26 are wear locations during the splitting process. The
removable mounting of the projections 16, 26 permits the projections to be
removed
and replaced as needed due to such wear. Tt is also preferred that the blades
14', 24'
be removable and replaceable, so that as the blades wear, they can be replaced
as
needed. The blades 14', 24' can be secured to the respective blade holders 1
S', 28'
through any number of conventional removable fastening techniques, such as by
bolting the blades to the blade holders, with each blade being removably
disposed
within a slot 25 formed in the respective blade holder as shown in Figure 11
for the
blade 14'.
The preferred top blade assembly 22' is about 2.5 inches wide as
measured between the side walls 28a, 28b of the blade holder 28'. The
projections
26 extend perpendicularly from the surfaces 29 and therefore strike the
working
piece at an angle.
The preferred bottom blade assembly 12' is about 4.0 inches wide as
measured between the side walls 15a, 15b of the blade holder 15'. The
projections
16 extend upwardly from shoulders 23 on opposite sides of the surfaces 19.
This
configuration breaks away more material and creates a more rounded rock-like
top
edge of the resulting split block (the workpiece is typically inverted or
"lips up"
during splitting because the workpiece is formed in a "lips up" orientation
that
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allows the workpiece to lay flat on what is to be the upper surface of the
resulting
block(s)).
The preferred bottom blade assembly 12' also includes adjustable and
removable proj ections 16 extending upward from the surfaces 19, as shown in
Figures 11 and 12. In this case, the projections 16 extend perpendicular to
the
surfaces 19 and strike the workpiece at an angle. The projections 16 extending
upward from the surfaces 19 and the projections extending upward from the
shoulders 23 can be of different sizes as shown in Figure 11, or of the same
size as
shown in Figure 12.
The angling of the projections 16 on the surfaces 19 of the blade
holder 15', and the angling of the projections 26 on the surfaces 29 of the
blade
holder 28', allows the projections 16, 26 to gouge into the workpiece and
break away
material primarily adjacent the bottom and top edges of the resulting block,
however
without breaking away too much material. As described below in more detail
with
1 S respect to Figure 12, the bottom blade assembly typically contacts the
workpiece
after the top blade assembly has begun its splitting action. The initial
splitting
action of the top blade assembly can force the resulting split pieces of the
workpiece
away from each other before the bottom blade assembly 12' and the angled
projections 16 can fully complete their splitting action. The vertical
projections 16
on the surfaces 23 of the blade holder 15' help to hold the split pieces in
place to
enable the angled projections 16 to complete their splitting action. The
vertical
projections 16 also break away portions of the split pieces adjacent the
bottom edges
of the resulting block(s). Thus, the angled and vertical projections 16 on the
bottom
blade holder 1 S' function together to preduce a rounded bottom edge on the
resulting
block, while the angled projections 26 on the blade holder 28' function to
produce a
rounded top edge on the resulting block.
In operation, the blade assemblies of Figures 8 and 11 are preferably
used together to split a workpiece, using the same cutting depth and hydraulic
pressures described above. It will be understood that the bottom blade
assembly
could be used on top, and the top blade assembly could be used on the bottom.
Referring now to Figure 10, a blade assembly 12' according to Figure
9 is depicted in position for striking a workpiece S8. The workpiece S8
comprises
portions which will result in small 60, medium 62 and large 64 blocks. The
1S
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projections 16 are preferably placed at appropriate locations on the blade
holder 15'
to create the three blocks 60, 62, 64 when the workpiece 58 is split. For
example,
the projections 16 can be located as shown in Figure 10. The upper blade
assembly
of Figure 8, which can be used in conjunction with the blade assembly of
Figure 9 to
split the workpiece 58, has similarly oriented projections except that they
are closer
to the.splitting line SL defined by the cutting edge 31. In this way, more
rounded,
rock-like edges on the resulting masonry blocks are formed in the splitting
process.
The positioning of the projections on the blade holders 15', 28' can be
used in conjunction with mold configurations that pre-form the workpiece 58 at
pre
determined locations to better achieve rounded, rock-like corners. For
example, the
walls of the mold that are used to form the workpiece 58 in Figure 10 can
include
suitable contoured portions so as to form the contoured regions 59a, 59b, 59c
in the
workpiece 58. The contoured regions 59a, 59b, 59c contribute to the formation
of
the rounded, rock-like corners when the workpiece 58 is split. Further
information
on the mold configuration that is used to create the workpiece 58 can be found
in co-
pending U.S. Patent Application Serial No. 09/691,931, filed on October 19,
2000,
which is herein incorporated by reference in its entirety.
Referring now to Figure 12, a gripper assembly 70 is shown in
conjunction with a preferred workpiece 68 for use in forming a pair of blocks
according to the invention. A bottom splitting blade assembly 12' according to
Figure 11, which is preferably used in combination with the top splitting
blade
assembly of Figure 8 to split the workpiece 68, is also shown in relation to
the
workpiece 68. Figure 12A illustrates the portion contained within line 12A in
Figure 12 in greater detail. The workpiece 68 is illustrated in dashed lines
for
clarity.
Gripper assembly 70 is employed to assist with splitting certain types
of larger block units. It is mounted via mounting head 71 on the existing side-
knife
cylinders of the splitting machine. Rubber shoes 72 are configured to conform
to the
corresponding outer surface of the workpiece 68. Each gripper assembly 70
moves
in and out laterally, as indicated by arrows, in order to grip the workpiece
68 from
both sides. In the preferred design, assembly 70 is about 3.0 inches high and
rubber
shoes 72 are 50-100 Durometer hardness. The pressure applied by the hydraulic
cylinders is the same as that for the upper and lower blades.
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One benefit of this gripper assembly is improving the formation of
rounded edges of a workpiece made by a bottom splitting blade assembly. A
workpiece 68 is moved along the manufacturing line by positioning bar 80 in
the
direction of the arrow shown. During splitting, while the rear portion of the
workpiece 68 is held in place by the bar 80, the forward portion is free to
move
forward. Many splitting machines have a splitting action whereby the bottom
blade
assembly moves to engage the workpiece after the top blade assembly has
touched
the top of the workpiece. The initial cutting action of the top blade assembly
can
begin to move the forward portion forward before the bottom blade assembly has
an
opportunity to fully form a rounded edge on the forward block with for example
projections 16 and/or surfaces 19. The bottom blade assembly can also lift the
workpiece 68, which is undesirable for a number of reasons. By holding the
workpiece 68 together during splitting, these problems are prevented.
tripper assembly 70 can optionally include projections 16, as shown
in Figures 12 and 12A. Projections 16 are preferably positioned slightly
inside the
top and bottom edges of the workpiece 68 (four proj ections for each gripper
assembly 70) so when they strike the side of the workpiece 68, more rounded
block
corners will be formed. The assembly 70 can also include a side knife
contained
within its central cavity 73, having a blunt blade such as those described
hereinabove, for forming rounded, rock-like side edges of the split blocks. It
may be
necessary to include an appropriate strength spring behind the side knife in
order to
get the desired action from the gripper and knife.
The preferred workpiece 68 is also formed to include contoured
regions 74, 75, 76, 77 at pre-determined locations to better achieve rounded,
rock-
like comers. For example, the walls of the mold that are used to form the
workpiece
68 in Figure 12 can include suitable contouring so as to form the contoured
regions
74-77,in the workpiece 68 (see Figure 13). The contoured regions 74-77
contribute
to the formation of the rounded, rock-like corners when the workpiece 68 is
split.
The contoured regions 74-77 preferably extend the entire height of the
workpiece
from the bottom surface to the top surface thereof.
The contoured regions 74, 75 are best seen in Figure 12A. It is to be
understood that the contoured regions 76, 77 are identical to the regions 74,
75 but
located on the opposite side of the workpiece 68. The contoured regions each
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include a convex section 78 having a radius R and a linear section 79 that
transitions
into the side surface of the workpiece 68. The shape of the contoured regions
is
selected to achieve satisfactory radiused corners on the block once the
workpiece 68
is split. Satisfactory results have been achieved using a radius R of about
1.0 inch, a
distance dt between the intersection of the convex section 78 with the linear
section
79 and the edge of the projection 16 of about 0.25 inches, a distance d2
between the
intersection of the convex section 78 with the linear section 79 and the
center of the
projection 16 of about 0.563 inches, and a distance d3 between the closest
points of
the convex sections 74, 75 of about 0.677 inches. Other dimensions could be
used
depending upon the end results sought.
Figure 13 illustrates a mold 84 that is used to form the workpiece 68.
The mold 84 is provided with two mold cavities 86a, 86b to permit simultaneous
formation of a pair of workpieces 68 and ultimately four blocks. Other mold
configurations producing a greater or smaller number of workpieces could be
used
as well. The walls of the mold 84 in each mold cavity include regions 88-91
that are
shaped to produce the contoured regions 74-77, respectively, on the worlcpiece
68.
A masonry block 100 that results from a splitting process on the
workpiece 68 using the splitting assemblies 12' and 22' of Figures 11 and 8,
respectively, is shown in Figures 14-16. The masonry block 100 includes a
block
body with a generally flat top surface 102, a generally flat bottom surface
104, side
surfaces 106, 108, a front surface 110 and a rear surface 112. The words "top"
and
"bottom" refer to the surfaces 102, 104 of the block after splitting and after
the bloclc
is inverted from its lips-up orientation during splitting. In addition, the
front surface
110 of the block 100 is connected to the side surfaces 106, 108 by radiused
sections
114, 116. The radiused sections 114, 116 have a radius of about 1.0 inch as a
result
of the contoured regions 74-77 on the workpiece. In addition, due to the
positioning
of the projections 16 on the blade assembly 12' shown in Figure 12, and the
similar
positioning of the projections 26 on the blade assembly 22', the upper left
and right
corners and the lower left and right corners of the block 100 at the radiused
sections
114, 116 are removed during the splitting process.
The radiused sections 114, 116 serve several purposes. First, they
present a more rounded, natural appearance to the block, as compared to a
block in
which the front face intersects the sides at a sharp angle. Second, in the
case of the
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sharply angled block, the splitting/distressing action produced by the
splitting blade
assemblies described here can break off large sections of the corners, which
can
create fairly significant gaps in the walls. Contact between adjacent blocks
in a wall
is often sought in order to act as a block for back fill material, such as
soil, that may
seep through the wall, as well as to eliminate gaps between adjacent blocks
which is
generally thought to detract from the appearance of the wall. If suitable
precautions,
such as the placement of filter fabric behind the wall, are not used, the fme
soils
behind the wall will eventually seep through the wall. The use of radiused
section
114, 116 appears to minimize the corner breakage to an acceptable degree, so
as to
preserve better contact or abutment surfaces with adjacent blocks in the same
course
when the blocks are stacked to form a wall.
In the blocks of Figures 14-16, the top and bottom surfaces 102, 104
do not have to be completely planar, but they do have to be configured so
that, when
laid up in courses, the block tops and bottoms in adjacent courses stay
generally
parallel to each other. Further, the front surface 110 of each block is wider
than the
rear surface 112, which is achieved by converging at least one of the side
surfaces
106, 108, preferably both side surfaces, toward the rear surface. Such a
construction
permits inside radius walls to be constructed. It is also contemplated that
the side
surfaces 106, 108 can start converging starting from a position spaced from
the front
surface 110. This permits adj acent blocks to abut slightly behind the front
face,
which in turn, means that it is less likely that fine materials behind the
wall can seep
out through the face of the wall. Such a block shape is shown in Figure 17.
The front surface 110 of the block has an irregular, rock-like texture.
In addition, an upper edge 118 and a lower edge 120 of the front surface 110
are also
irregular as a result of the projections 16, 26 on the splitting blade
assemblies 12',
22'. As a result, the front surface 110 and the edges 118, 120 are provided an
irregular, rock-like appearance. Further, the entire front surface 110 is
slightly
rounded from top to bottom when viewed from the side. The edges 118, 120 are
also rounded.
Figures 14 and 16 also illustrate the radiused sections 114, 116 and at
least a portion of the side surfaces 106, 108 as being lightly textured. The
light
texturing is achieved using a horizontal groove or channel that is formed in
the mold
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walls at the locations where light texturing on the workpiece and resultant
block is
desired.
Figure 19 illustrates a portion of a mold wall 117 from the mold 84 in
Figure 13 having a generally horizontal channel or groove 119 provided in the
wall
close to the bottom of the wall. Figure 20 is a cross sectional view of the
wall 117
showing the shape of the channel 119. The mold wall 117 corresponds to one of
the
surfaces of the block that is to be lightly textured, such as the side surface
106. The
channel 119 is illustrated as extending along a portion of the wall 117, in
which case
light texturing of only a portion of the corresponding surface of the
workpiece will
occur. However, the channel 119 can extend along the entire length of the wall
117
if light texturing is desired along the entire corresponding surface.
The channel 119 is illustrated as being rectangular in cross section.
However, other shapes can be used such as semi-circular (see Figures 23 and
23A),
v-shaped (see Figure 26), or ear-shaped, and multiple grooves or channels (see
Figures 22, 22A, 24 and 25) can be used. These multiple grooves or channels
can be
at the same or different heights on the mold wall. The channels may be
generally
parallel to the bottom of the mold (see Figure 25) or they may be skewed (see
Figure
22) or even non-linear such as serpentine (see Figure 27). Criss-cross
patterns can
be used (see Figure 24). The grooves) may extend partly or entirely across the
mold wall. For reasons not presently understood, some of the channel patterns
(e.g.
criss-cross) tend to be repeated or mirrored in the surface of the finished
masonry
units, which produces interesting visual effects when the masonry units are
assembled into a wall or other structure.
The channel 119 in Figures 19 and 20 preferably has a height of
about 0.50 inches, a depth of about 0.060 inches, and the channel I 19 begins
about
0.090 inches from the bottom of the wall 117. Other channel dimensions, in
addition to channel shapes, could be used, with variations in the resulting
light
texturing that is produced.
For example, Figure 22 is a front view of a mold wall 200 in which
multiple shallow diagonal grooves or channels have been cut in the wall at an
angle
to the horizontal of about 30 degrees. With reference to Figure 22A, a typical
size
for the channels is about 0.25 inches wide G, about 0.03 inches deep D, and a
space
S of about 0.25 inches between channels. Alternatively, the grooves or
channels can
CA 02426192 2003-04-17
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be cut in the wall at an angle to the horizontal of about 45 degrees, and be
about 0.5
inches wide G, about 0.03 inches deep D, and be spaced S about 0.50 inches
apart.
Figure 22A is a sectional view of the mold wall 200 shown in Figure 22 to show
the
shallow, rectangular cross section of the grooves.
Figure 23 is a front view of the mold wall 200 in which a single
horizontal groove or channel has been cut in the wall close to the bottom of
the wall.
A suitable size for the channel, which is semi-circular in cross-section, can
be about
0.375 inches diameter (dimension G in Figure 23A) and the channel is within
about
0.1 inches of the bottom of the wall. Alternatively, the channel could be
rectangular
in cross-section.
Figure 24 is a front view of the mold wall 200 in which multiple
diagonal grooves or channels have been cut in the wall at an angle to the
horizontal
of about 45 degrees to provide a "criss-cross" pattern. The channels are about
0.5
inches wide, about 0.03 inches deep, and are spaced about 0.5 inches apart.
Figure 25 is a cross-sectional view of the mold wall in which multiple
horizontal grooves or channels have been cut in the wall, extending from near
the
bottom of the mold wall to near the top of the mold wall. The channels are
about
0.1875 inches wide, about 0.09 inches deep and spaced about 0.1875 inches
apart
starting about 0.050 inches from the bottom of the wall.
Figure 26 is a cross-sectional view of the mold wall in which a single
horizontal groove or channel has been cut in the wall close to the bottom of
the wall.
The channel is preferably about 0.500 inches wide, about 0.020 inches deep,
and
starts about 0.050 inches from the bottom of the mold wall. It is V-shaped in
cross
section.
Figure 27 illustrates a serpentine groove or channel in the mold wall.
The channels) shown in Figures 22-27 can be used with the mold
wall 117 in Figure 19, in addition to being used on other walls of the mold
84, as
well as being used on walls of other masonry unit molds, such as a mold wall
for a
brick mold. The preferred arrangement is to form a single, shallow, horizontal
channel near the bottom edge of the mold wall. By "°shallow" it is
meant that the
ratio of the width G of the channel (see Figure 22A) to the maximum depth D of
the
channel is at least about 1:1, and is often greater than 1:1 (e.g. at least
about 2:1).
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It has been discovered that the provision of the channel 119 causes
texturing of the corresponding surface of the molded workpiece as it is
discharged
from the mold. Although not wishing to be bound to any theory, it is believed
that
some of the fill material used to form the workpiece temporarily resides in
the
channel 119 during the molding process. This is referred to as "channel fill
material". As the compressed and molded fill material is discharged from the
mold
cavity, this channel fill material begins to be disturbed or disrupted by the
movement
of the workpiece within the mold cavity and the channel fill material is
caused to
tumble or roll against the passing surface of the workpiece, imparting a
slightly
rough texture to it. It seems likely that the channel fill material is
constantly being
changed/replenished as the workpiece passes by the channel during discharge of
the
workpiece from the mold. Regardless of the mechanism, the surface of the
passing
workpiece is given a slightly rough texture by this process. This effect can
be
achieved by means of a single channel, or by means of a series of channels. At
least
one of the channels will be oblique (preferably perpendicular) to the
direction of
stripping the workpiece from the mold. This is important so that one does not
merely create a vertical stripe or series of vertical stripes on the
corresponding face
of the block.
The depth and height of each channel will be selected to provide the
optimum or desired surface texturing for the intended application, taking into
consideration the mix design for the fill material, which includes aggregate
size and
distribution. It has been noted that if the channel is too large, some large
aggregate
can be held within the channel during the block making process, and the larger
aggregate held in the channel may cause the face of the workpiece to be scored
so
that it is readily visible when looking at the finished block or other masonry
unit
(usually an undesirable result).
For most applications, it has been found that the height of the channel
(e.g. dimension G of Figure 22A) will be less than about 0.75 inches, and
usually
less than about 0.6 inches. Channel heights of from about 0.15 to about 0.6
inches
are particularly useful. Channel depths (dimension D of Figure 22A) are
usually
less than about 0.5 inches and usually less than about 0.35 inches. Depths of
about
0.1 to about 0.25 inches are quite desirable. In general, if the channel is
made wider,
it should also be made shallower so that the amount of channel fill material
is not
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too great, and large aggregate will not be held in the channel. When the
masonry
unit is discharged from the mold cavity, any channel fill material remaining
in the
channels) will tend to fall out of the channel, especially during the
vibration of the
mold. In this sense, the preferred mold designs are self cleaning, and it is
not
necessary to interrupt production to clear the mold wall of compacted fill
material.
By making the channels shallow, fill material is not retained in the channels
from
cycle to cycle so that it can harden. This is undesirable and will defeat the
desired
goal of having fresh, uncured, soft fill material tumble or roll against the
passing
surface of a concrete masonry unit being discharged from the mold cavity.
As shown in Figure 23, the wall has a height H and a width W for a
total projected surface area equal to HxW. In a similar fashion, the channel
has a
height G for a total projected surface area equal to GxW. The ratio of HxW
divided
by GxW is a useful measure of how much channeling has been done to the surface
of the mold wall. In practice, this ratio of total projected area of the mold
wall to the
total projected area of the channels) will usually be more than about 2:1 and
preferably more than about 4:1. Ratios of about 10-50:1 are usually optimum.
This
means that the desired surface texturing can be obtained with only a modest
amount
of channeling. This simplifies construction of the mold. For many
applications, it is
preferred to use a single horizontal channel located within about 0.5 inches,
and
usually less than about 0.1 inches, of the Iower edge or bottom of the wall,
and
extending substantially completely across the wall.
Typically, at least one of the channels will be spaced from the top of
the wall by more than 40% of the distance H from the top to the bottom of the
wall
and more usually, at least one of the channels will be at or below the mid-
point of
the wall (50 % of H). Placing at least one of the channels further down the
wall (e.g.
at least 60% of the way down and preferably at least 75% of H) will provide
more
desirable surface texturing for most applications. In this regard, the
location of the
channel determines where on the workpiece the texturing begins, since the face
of
the molded workpiece below the lowest channel is not affected by the action of
the
channel and will retain its natural surface finish. Where it is desired to
achieve
surface texturing of alinost the entire corresponding surface of the
workpiece, at
least one channel should be placed as close to the bottom of the wall as is
practical.
Typically this will be within about O.I inch of the bottom of the wall. By
contrast,
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moving the lowest channel up the wall will result in a portion of the face of
the
molded workpiece being textured and a portion will not be textured. This
cosmetic
look (partially textured and partially smooth surface) may be desired for some
applications.
In addition, a channel could vary in height and/or depth over its
length which could lead to different surface texturing effects on the
corresponding
surface of the workpiece, which may be a desired cosmetic look for some
applications.
The use of a channel or groove in a mold wall can be used to produce
a light, modest or fine textured surface on blocks, as well as on bricks,
payers and
other molded masonry units. The texturing is achieved without using protruding
lips, wall projections, or grates (as found in U.S. Patents 3,940,229;
5,078,940;
5,217,630; 5,879,603; and 6,113,379), although such features could be used to
supplement the action described herein. However, the rapid wear problems
associated with thin protruding lips can be minimized, as can damage to
protruding
lips resulting from head misalignment. In addition, the channels) can be
provided
on other shaping surfaces of a mold, including surfaces that are not planar.
Further details on molds and grooves or channels in mold walls to
achieve texturing can be found in co-pending U.S. Patent Application Serial
Nos.
091691,931 and 09/691,898, each of which was filed on October 19, 2000, and
which are incorporated herein by reference in their entirety.
Preferably, at least the radiused sections 114, 116 and the front
portion of the side surfaces 106, 108 are lightly textured. This is important
because
the irregularities produced by the projections 16, 26 can expose portions of
the block
sides when the blocks are laid up in a wall. The texturing of these side
surfaces has
the effect of disguising the manufactured appearance of the exposed portions
of the
blocks. If no texturing is employed, then the generally smooth, somewhat shiny
sides of the blocks tend to look very manufactured. It is preferred that the
texturing
be produced along about 3.0 to about 8.0 inches of each block side, extending
over
each radiused portion and a portion of each side surface, as measured from the
front
surface of a 12 inch long block. However, it is contemplated and within the
scope of
the invention to texture more of the side surfaces than just the front
portions thereof,
including the entirety of the side surfaces, and to texture the rear surface
112.
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The material used to form the masonry block 100 is preferably a
blended material to further add to the natural, weathered rock-like
appearance. As
is known in the art, f 11 materials that are used to make blocks, bricks,
pavers and the
like, contain aggregates such as sand and gravel, cement and water. Fill
materials
may contain pumice, quartzite, taconite, and other natural or man-made
fillers. They
may also contain other additives such as color pigment and chemicals to
improve
such properties as water resistance, cure strength, and the like. The ratios
of various
ingredients and the types of materials and sieve profiles can be selected
within the
skill of the art and are often chosen based on local availability of raw
materials,
technical requirements of the end products, and the type of machine being
used.
Preferably, the fill material that is used to form the block 100 is
formulated to produce a blend of colors whereby the resulting front face 110
of the
split block 100 has a mottled appearance so that the front of the block
simulates
natural stone or rock. For instance, as shown in Figure 14, the front face 110
has a
mottled appearance produced by a plurality of colors 122, 124. One or more
additional colors could be added in order to alter the mottled appearance.
However,
in instances when a mottled appearance is not desired, a single color fill
material or
a natural aggregate mix could be used.
When a mottled appearance is sought, the fill material that is used to
form the workpiece and thereby the resulting blocks) is preferably introduced
into
the mold using a divided gravity hopper and a feedbox, which are known in the
art,
above the mold. Figure 21 shows a top view of a hopper 170 and a partition
plate
172 that is mounted in the hopper 170 to help produce a swirling of colors in
the fill
material. The partition plate 172 extends across the width of the hopper 170,
with
the edges of the plate 172 being removably disposed within channels 174, 176
formed on the hopper to enable removal of the plate 172. The plate 172 also
extends
vertically within the hopper 170.
The plate 172 is comprised of an arrangement of baffles 17~ that are
intended to randomly distribute each fill material color as it is poured into
the
hopper 170. Each fill material color is poured separately into the hopper,
with the
plate 172 randomly distributing each color onto any material previously poured
into
the hopper. The sucking action of the feedbox on the hopper as fill material
is
discharged into the feedbox further contributes to a random distribution of
the
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various colors in the fill material. Moreover, an agitator grid, which is
known in the
art, is present in the feedbox for leveling the fill material. The action of
the agitator
grid also contributes to the swirling of the colors in the fill material.
The fill material with the randomly distributed or swirled colors is
then transferred from the feedbox into the mold to produce the workpiece. The
swirling of the colors in the fill material produces the mottled appearance on
the
front surface of the block 100 once the workpiece is split. The swirling
produced by
the plate I72, the sucking action of the feedbox, and the agitator grid is
random, so
that the swirling of colors in each workpiece and the resulting mottled
appearance on
each block, is generally different for each workpiece and block formed. In
addition,
the mottled appearance of the front surface will vary depending upon where the
workpiece is split due to the random swirling of the colors in the workpiece.
An example of a composition, on a weight basis, of one fill material
that can be used to produce a mottled appearance using a 3-color blend is as
follows:
Gray (1/2 batch) Charcoal (1/2 batch) Brown 1/2 Batch)
Sand 2500 2500 2500
Buckshot 1000 1000 1000
Cement 275 275 275
F'lyash 100 100 100
Additives:
RX-901 19oz. RX-901 I 9oz. RX-901 19oz.
Color:
No color added Black 330 3.75 lbs. Red 110 5.10 lbs
Black 330 S.lOlbs
RX-901, manufactured by Grace Products, is a primary efflorescence
control agent that is used to eliminate the bleeding of calcium hydroxide or
"free
lime" through the face of the block.
~ther fill material compositions could be used as well depending
upon the desired mottled appearance of the block front face, the above listed
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WO 02/40235 PCT/USO1/50186
composition being merely exemplary. For instance, a two-color fill material
could
be used.
Once the fill material has been prepared, it is transported to the block
forming machine, and introduced into the mold in the commonly understood
fashion. The block forming machine forms "green", uncured workpieces, which
are
then transported to a curing area, where the workpieces harden and gain some
of
their ultimate strength. After a suitable curing period, the workpieces are
removed
from the kilns, and introduced to the splitting station, adapted as described
above,
where the workpieces are split into individual blocks. From the splitting
station, the
blocks are transported to a cubing station, where they are assembled into
shipping
cubes on wooden pallets. The palletized cubes are then transported to an
inventory
yard to await shipment to a sales outlet or a jobsite.
The block 100 also includes a locator lip or flange 126 formed
integrally on the bottom surface 104 adj acent to, and preferably forming a
portion
of, the rear surface 112. The lip 126 establishes a uniform set back for a
wall
formed from the blocks 100, and provides some resistance to shear forces. In
the
preferred configuration, the lip 126 is continuous from one side of the block
100 to
the other side. However, the lip 126 need not be continuous from one side to
the
other side, nor does the lip 126 need to be contiguous with the rear surface
112. A
different form of protrusion that functions equivalently to the lip 126 for
locating the
blocks could be used.
The block shape shown in Figures 14-I6 is preferred. However, it is
contemplated and within the scope of the invention to utilize the concepts
described
herein, including the irregular edges produced by the projections 16, 26,
and/or the
texturing of the side surfaces, and/or the mottled appearance of the front
surface, on
other block shapes. In addition, the block 100 could be formed with internal
voids
to reduce the weight of the block 100.
For example, Figure 17 illustrates a block 150 that is provided with
an irregular front face 152 with irregular edges 152a, 152b, texturing of a
portion of
side surfaces 154, 156 (only one side surface 154 and the texturing thereon is
visible
in Figure 16), and a mottled coloration of the front face 152. Like the block
100, the
entirety of the side surfaces 154, 156, as well as a rear surface 158, could
be
textured. The block 150 is preferably split from a suitable workpiece using
the
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WO 02/40235 PCT/USO1/50186
splitting assemblies 12' and 22' of Figures 11 and 8, respectively. The
general shape
of the block 150 is similar to that disclosed in Figures 1-3 of U.S. Patent
5,827,015.
Other block shapes could be provided with one or more of these features as
well.
In the preferred embodiment, the block 100 is one of a pair of blocks
that results from splitting a workpiece, such as the workpiece 68 in Figure
12, using
splitting blade assemblies of the type illustrated in Figures 8 and 11.
Different block
sizes can be formed by reducing or enlarging the size of the workpiece from
which
the blocks are produced. However, as discussed above with respect to Figure
10, the
workpiece 58 could be formed and then split to produce three different block
sizes,
each of which is similar to the block 100. In addition, it is contemplated and
within
the scope of the invention that a single one of the blocks 100 could be formed
from a
workpiece that, after splitting, results in a waste piece in addition to the
block 100.
Figure 18 illustrates a wall constructed from three differently sized
blocks, with each block having a configuration similar to the block 100.
There may be instances when it is satisfactory that a block be
provided with only one irregular edge on the front face. Therefore, it is
contemplated and within the scope of the invention that a workpiece could be
split
using a single one of the splitting assemblies described herein. Further, a
splitting
assembly could have projections that are disposed on only one side of the
splitting
line.
The above specification, examples and data provide a complete
description of the manufacture and use of the composition of the invention.
Since
many embodiments of the invention can be made without departing from the
spirit
and scope of the invention, the invention resides in the claims hereinafter
appended.
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