Note: Descriptions are shown in the official language in which they were submitted.
CA 02642441 2008-10-30
BLOCK DRESSING MACHINE
Background
[0001] This application relates generally to machines used to fabricate
building blocks.
More particularly, this application relates to a machine for dressing
externally
viewable surfaces of blocks used to construct retaining walls, free-standing
walls,
paved surfaces, and the like.
[0002] Building blocks are widely used in a variety of applications, and can
be used to
retain soil, as fences, as structural components of buildings, as sidewalk
surfaces,
and as road surfaces. A particular style of building block that is increasing
in
popularity is the rustic or weathered look. Rustic or weathered look blocks
are
desirable for several reasons. They convey the impression of craftsmanship
that is
nowadays frequently absent. They convey a sense of security and stability.
And,
they are visually pleasing to an observer.
[0003] A variety of approaches have been used to create rustic appearing
blocks. The
most elementary and straightforward approach is to take a molded block and
hand
dress or roughen the surface using hammer and chisel. Another approach has
been
to provide a patterned mold that is able to simulate a rustic surface.
Unfortunately,
while it eliminates the step of hand dressing, a user is more-or-less stuck
with the
product as it comes from the mold. Any modification thereafter would defeat
the
purpose of such a block. Another approach is to take a molded block and place
it in
a rotatable container that tumbles it about (preferably, with other blocks or
suitable
material). The problem with this approach is that as a block is being tumbled,
all of
the exterior surfaces, including critical locater protrusions and mating
surfaces, are
being ground down. If the protrusions are knocked off or damaged during the
tumbling process, the ability to interlock and/or provide proper spacing is
compromised. Another approach attempts to form rustic surfaces by splitting a
block
into smaller segments along a predetermined plane. This creates two blocks,
each
with a front face that has the appearance of a natural split rock. While
attractive, the
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split surfaces do not convey the impression that they were hand worked. Yet
another approach uses flails to modify the externally viewable surfaces of
blocks.
Typically, the flails comprise short sections of chain one end of which is
affixed
about the perimeter of a rotatable shaft, the other end of which may be
provided with
an enlarged head of steel or other similar material. In operation, the flail
ends (with
the enlarged heads as the case may be) strike the entire front surface of a
block as
they are swung about by the rotatable shaft.
Summary
[0004] In one embodiment, a machine works externally viewable surfaces of
building blocks
so that they appear to have been hand dressed. For purposes of this
application,
the term block (or masonry block) is intended to include any naturally
occurring
material, manmade material, molded cementitious block, natural and artificial
stone
or like material that may be used for buildings, indoor walls, partitions,
facades,
retaining walls, walkways, freestanding walls or fences, capstones, pavers, or
other
similar structures, with or without the use of mortar or its functional
equivalents.
[0005] In a preferred embodiment, the machine comprises a main frame, a
transport
section, and a block modifying section. The main frame is constructed and
arranged
to support the transport section, which comprises a movable support portion
and a
stabilizer portion. The movable support portion includes an upper surface upon
which one or more blocks may be positioned. An inboard fence, located adjacent
to
one side of the movable support portion, serves as a guide for a block as it
is moved
through the transport section. Preferably, the movable support portion is
oriented so
that it is substantially horizontal. The stabilizer portion is located above
the movable
support portion and is vertically adjustable relative thereto. The movable
support
portion and the stabilizer portion are configured so that they are able to
contact
external surfaces of one or more blocks moved by the transport section.
Preferably,
the movable support portion and the stabilizer portion are configured to
contact
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opposing external surfaces of a block so as to effectively grip a block being
processed. The gripping ability of the transport section is enhanced by
providing the
stabilizer portion with one or more biasing elements that exert a force
towards the
movable support.
[0006] A block modifying section is located to one side of the transport
section and
comprises one or more primary modifiers that have one or more hammer elements.
The one or more hammer elements are configured and arranged to be actuated in
a
direction that is generally orthogonal to the side of the transport section.
Preferably,
with each primary modifier, there is a plurality of hammer elements arranged
in a
matrix or array. The hammer elements are attached to a housing so as to form a
block modifying unit or module, which is operatively connected to a platform.
The
platform may be adjustably positioned relative to the transport section.
Preferably,
there are approximately 7 to approximately 15 hammer elements in each unit or
module. Additionally, the unit or module may be angularly positioned relative
to the
transport section. Two or more units or modules may be positioned adjacent
each
other in a side-by-side relation. As will be appreciated, the two units act in
concert
with each other and are arranged so that they are in a vertically staggered
relation.
As will be appreciated, when a block of material is moved relative to the
primary
modifiers, the impact zones of the hammer elements will preferably overlap.
Preferably, one end of the platform that holds the block modifying units is
operatively
connected to either the main frame or the movable support portion, while the
other
end of the platform is operatively connected to the stabilizer portion. When
the
stabilizer portion moves vertically relative to the main frame (and the
movable
support portion connected thereto), the position of the primary modifiers is
automatically adjusted. In operation the hammer elements, which may have
independent motion, are able to strike and impact a surface of a block in a
vibratory
fashion as the block is being moved relative to the primary modifiers.
[0007] The block modifying section of the machine may also be provided with
one or more
secondary modifiers. The secondary modifiers may be used to dress the edges or
arrises of the block so as to produce irregular edges. A preferred secondary
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modifier comprises a pair of rotatable drums. Each drum is provided with a
plurality
of radially extending teeth that are spaced about the surface of the drum and
which
are rigidly attached thereto. Preferably, the teeth have at least one
impacting
surface and are arranged in one or more circumferential rows, spaced axially
from
each other along the rotational axis of the drum. Preferably, the teeth in
each
circumferential row are evenly spaced from each other. And, preferably,
adjacent
circumferential rows of teeth are offset from each other. The rotatable drums
are
operatively connected to the main frame (or the movable support portion) and
the
stabilizer portion of the transport section, so that as the stabilizer portion
is raised
and lowered the upper drum automatically maintains its position to accommodate
differently sized blocks. Preferably, the rotatable drums and are situated so
that
they may work several disparate, viewable edge sections of a block before it
reaches the primary modifiers.
[0008] Another embodiment of a secondary modifier includes one or more sub-
units or sub-
modules have one or more hammer elements. The hammer elements are
configured and arranged to be actuated in a direction that is generally
perpendicular
to the longitudinal axis of the transport section. Preferably, the hammer
elements of
each sub-unit or module are arranged in a matrix or array. The hammer elements
are attached to a housing, which is movably attached to a bracket and the
bracket
may be adjustably positioned relative to the transport section. Additionally,
the sub-
unit or module may be angularly positioned relative to the transport section.
Two or
more sub-units or modules are positioned so that they are able to work one or
more
arrises or edges of a block. In operation the hammer elements, which may have
independent motion, are able to strike and impact selected portions of a block
as it is
being moved by the transport section of the machine. Preferably, the sub-units
or
modules and are situated so that they may work several disparate, viewable
edge
sections of a block after it passes the primary modifiers. However, it will be
understood that the sub-units or modules may be positioned before the primary
modifiers, if desired.
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[0009] The machine includes an inboard fence and adjustable outboard fences.
The
inboard fence, positioned along one side of the movable support portion,
guides a
block as it moves through the machine. A preferred embodiment of an outboard
fence comprises a flexible, endless belt that is positioned about the
rotatable
elements and held in tension due to the spring-biased arms. In use, the
outboard
fence is located adjacent to and slightly above the surface of the movable
support
portion so that the belt (and the spring biased rotatable elements) is able to
contact
the rear (or non-worked) surfaces of one or more blocks as they are being
processed by the machine. Preferably, the outboard fence may be adjustably
positioned towards and away from the transport section so as to accommodate
different sized blocks.
[0010] In an alternative embodiment, the outboard fence comprises an elongated
body that
includes first and second ends, a first or horizontal wall, and a second or
vertical
wall. Preferably, the fence is movably positionable relative to the inboard
fence so
as to accommodate blocks having different depths (the z dimension in a three
dimensional coordinate system).
[0011] The machine may be provided with an optional upper outboard fence that
is
associated with the stabilizer portion of the transport section. The upper
fence
comprises an elongated body that includes first and second ends, a first or
horizontal wall and a second or vertical wall. The upper fence may include a
third
wall that is connected to the first and second walls, and which is angled
relative
thereto. The third wall presents a surface that can guide a block by
contacting an
upwardmost extending rear edge thereof. The position of the upper outboard
fence
may be adjusted in the y and z directions in a three dimensional coordinate
system
to accommodate blocks having different heights and depths.
[0012] The above machine may be used with a wide variety of preformed building
blocks
having a wide variety of sizes and surface textures. And, with a single
machine, it is
possible to work a single or multiple areas of an exterior surface. However it
is
envisioned that two single surface machines can be connected to each other in
an
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end-to-end manner so that the output end of a first machine confronts the
input end
of the second machine, and so that the block modifying section of the first
machine
and the block modifying section of the second machine face work opposite
surfaces
of a block.
[0013] The machines described here are able to dress externally viewable
surfaces of a
building block, increase the speed at which rustic masonry blocks may be
fabricated,
and use a transport section to effectively grip one or more blocks as they are
processed by the machine.
[0014] These machines have a block modifying section that includes one or more
hammer
elements that percussively engage an externally viewable surface of a block.
They
may be adjusted to provide different knapping depths, or to accommodate
differently
sized blocks.
[0015] An advantage of the machines is that externally viewable surfaces of a
block may be
randomly impacted by a plurality of hammer elements whose impact zones
overlap.
[0016] Another advantage is that various externally viewable surfaces of a
block may be
selectively processed.
[0017] A third advantage is that the machines are able to accommodate a
variety of
differently shaped blocks.
[0018] Yet another advantage of the invention is that a plurality of building
blocks may be
dressed in an expedient and efficient manner.
[0019] These and other objectives, features and advantages will appear more
fully from the
following description, made in conjunction with the accompanying drawings
wherein
like reference characters refer to the same or similar parts throughout the
several
views. And, although the disclosure hereof is detailed and exact, the physical
embodiments herein disclosed are merely examples that may be embodied in other
specific structures. While preferred embodiments have been described, the
details
may be changed without departing from the claims.
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Description of the Drawings
[0020] Figure 1 is a perspective representation of an embodiment of a block
dressing
machine;
[0021] Figure 2 is a front elevational view of the block dressing machine of
Figure 1;
[0022] Figure 3 is a left side elevation view of the block dressing machine of
Figure 1;
[0023] Figure 4 is a right side elevational view of the block dressing machine
of Figure 1;
[0024] Figure 5 is a top plan view of the block dressing machine of Figure 1;
[0025] Figure 6a is a front perspective view of the stabilizer portion and the
crossbeam or
carriage of Figure 1;
[0026] Figure 6b is a rear perspective view of the stabilizer portion and the
crossbeam or
carriage of Figure 1;
[0027] Figure 7 is a partial perspective view of the movable support portion
of the transport
section, primary and secondary block modifiers, and the outboard and inboard
fences of Figure 1;
[0028] Figure 8a is a skeletonized, front elevational view of a block
modifying section;
[0029] Figure 8b is a top plan view of Figure 8a;
[0030] Figure 9 is a front elevational view of primary modifier units attached
to a platform;
[0031] Figure 10a is a perspective view of a primary modifier;
[0032] Figure 10b is a front plan view of the primary modifier of Figure 10a;
[0033] Figure 10c is a side elevational view of the primary modifier of Figure
10a;
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[0034] Figure 10d is a top plan view of the primary modifier of Figure 10a;
[0035] Figure 11 is a perspective view of an alternative secondary block
modifiers as they
may be positioned adjacent the movable support and stabilizer portions of the
transport section;
[0036] Figure 12 is a perspective view of an embodiment of a fence; and
[0037] Figure 13 is a perspective view of another preferred embodiment.
Detailed Description
[0038] In a preferred embodiment, the machine 10 of the present invention
comprises a
main frame 20, a transport section 12, and a block modifying section 18. The
main
frame 20, as shown in Figures 1-4, includes a bed and a superstructure that
are
supported by a plurality of horizontal beams 30, 32, 34, 36, 40, 42, 44, 46
and
vertical legs 22, 24, 26, 28. The superstructure extends vertically over the
bed in a
cantilevered fashion. The transport section 12, which includes a movable
support
portion 56 with a horizontal movable surface 84 and a stabilizer portion 58,
are
connected to the bed and the superstructure, respectively. Preferably, the
stabilizer
portion 58 may be selectively positioned in the vertical direction, relative
to the
movable support portion 56. This allows the transport section 12 to
accommodate
blocks having different sizes and shapes to be processed by the machine 10.
[0039] The preferred movable support portion 56 is a conveyor that includes an
elongated
box-shaped frame 60 with an upper surface (not shown) opposite ends that
rotatably
support cylindrically shaped rollers 64, 66, and an endless belt 70 is
entrained about
the upper surface and the rollers. The movable support portion 56 is movably
powered by a conventional motive source 74 such as a hydraulic or electric
motor
and a coupler 75. The endless belt 70 is generally horizontal and is of
sufficient
width and length so as to be able to support one or more blocks placed
thereon. A
preferred inboard fence 80, located adjacent to one side of the movable
support
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portion 56, serves as a guide for a block as it is moved through the machine
10 by
the transport section 12. The inboard fence 80 comprises an elongated body 82
having planar horizontal upper surface 84 and a plurality of vertical walls
86, 88, 90,
with the walls in longitudinal alignment with each other along the elongated
body.
Between the walls 86, 88, 90 of the inboard fence 80, there are gaps 92, 94,
96 that
provide relief for portions of the block modifying section 18. As can be seen
in
Figures 8a, 8b, and 11, the gaps 92, 94, 96 enable teeth 208 of rotatable drum
204
and hammer elements 152 and 236 of impacting units 162 and 234, respectively,
to
engage selected portions of a viewable surface of a block.
[0040] The preferred stabilizer portion 58 is also a conveyor that includes an
elongated box-
shaped frame 100 with a lower surface (not shown), opposite ends that
rotatably
support cylindrically shaped rollers 110, 112, and an endless belt 114 is
entrained
about the lower surface and the rollers. The stabilizer portion 58 is movably
powered by its own conventional motive source 118 such as a hydraulic or
electric
motor that is connected to the stabilizer portion 58 by a coupler 119. In use,
the
stabilizer portion 58 is positioned vertically, relative to the movable
support portion
56 such that the outer (or bottom) surface of the belt 114 is able to contact
upper
surfaces of one or more blocks positioned on top of the movable support
portion 56.
[0041] The stabilizer portion 58 is operatively connected to a horizontally
oriented
crossbeam or carriage 120 that is movably connected to the superstructure 48
of the
main frame 20. The preferred crossbeam or carriage 120, which extends
substantially along the length of the machine 10, includes opposing ends with
vertically aligned apertures 122, 124, each of which slidingly receives a
vertical
guide column 50, 52 that is connected to the frame 20. The crossbeam or
carriage
120 is connected to a pair of vertical jack screws 130, 132 (shown covered by
flexible, protective tubes) that are rotatably mounted to the superstructure
48, and
which extend downwardly into threaded apertures 126, 128 at the ends of the
crossbeam 120. Both of the jack screws 130, 132 are operatively connected by
gearing and drive shafts 144 to a single motive source 146 such as a hydraulic
or
electric motor. In operation the motive source 146 rotates the jack screws
130, 132
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in concert, which, in turn, moves the crossbeam 120 (and the stabilizer
portion 58
connected thereto) in a vertical direction, as desired.
[0042] In operation, the movable support portion 56 and the stabilizer portion
58 are
configured to contact external surfaces of one or more blocks as they move
through
the transport section 18. Preferably, the movable support portion 56 and the
stabilizer portion 58 are configured to contact opposing external surfaces of
a block
so as to effectively grip a block being processed. The gripping ability of the
transport
section 18 is enhanced by providing the stabilizer portion 58 with one or more
biasing elements 102 that exert a force towards the movable support portion
56. A
preferred biasing element 102 is in the form of a resilient panel 104 having a
generally z-shaped cross-section, with the panel having an upper arm segment
106,
a diagonally oriented body, and a lower leg segment 108, is shown in an inset
in
Figure 6A. In use, the upper arm segment 106 is preferably connected to the
stabilizer portion 58 so that it faces the input end of the transport section
18 and the
lower leg segment 108, which bears against the inside surface 73 of the
conveyor
belt 70, faces towards the output end of the transport section 12. Preferably,
there is
a plurality of resilient panels 104, arranged in a sequential order between
the end
rollers 110, 112, which bias a significant portion of the bottom surface of
the belt 114
of the stabilizer portion 58 towards the movable support portion 56. If a
block having
a vertically extending protrusion (such as, for example, an interlocking lip
on the
bottom surface of an inverted block) passes through the transport section 12,
the
biasing elements 102 will automatically compensate for such variation, and the
belt
114 will be able to maintain contact with the block. Other types of biasing
elements
102 may be used. For example, resiliently mounted rollers. In operation, the
belts
70, 114 of the movable support portion 56 and the stabilizer portion 58
preferably
move at the same speed, which can range from about 0-to-100 feet per minute.
[0043] Generally, the block modifying section 18 is located to one side of the
transport
section 12 and comprises one or more primary modifiers 150 and one or more
secondary block modifiers 200, 230. A preferred primary modifier 150 is a
generally
rectangularly shaped housing 162 having an exterior surface 164 with a top, a
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bottom, sides, a back and a front. The rectangular housing 162 forms a
modifying
unit or module 150 that is used to work a major, viewable surface of a block.
To that
end, the modifying unit or module 150 is provided with one or more hammer
elements 152 that are movably connected thereto, and which protrude from
apertures 168 in the front 166 of the modifying unit. Preferably, there are
approximately 7 to approximately 15 hammer elements 152 in each modifying unit
or
module 150, with the hammer elements arranged into a pattern or matrix. More
preferably, each unit or module 150 includes 11 hammer elements 152 arranged
in
two offset rows.
[0044] The housing 162 is operatively connected to a frame or platform 170 so
that the
hammer elements 152 face the transport section 12. The platform 170 may be
adjusted in one of several directions, relative to the transport section 12.
That is, the
platform 170 may be adjusted so that the hammer elements 152 are able to be
repositioned towards and away from the transport section 12, as desired. A
preferred adjustment mechanism comprises a pair of jack screws that are
operatively connected to the main frame 20 and which drivingly engage the
plafform
170 so that it may move relative to the transport section 12. Preferably, the
jack
screws are connected to each other by way of sprockets 185 and a chain 187 so
that they are able to operate in concert. A motive source 189 such as a
hydraulic or
electric motor may be used to power the adjustment mechanism. As the hammer
elements 152 are moved closer to the transport section 12, the amount of block
material that can be removed increases.
[0045] Additionally, the platform 170 may be adjustably angled, relative to
the transport
section 12. To facilitate such adjustability, one end 172 of the platform 170
is
pivotally connected to a shaft 182 that extends perpendicularly from the
movable
support portion 56. The other end 172 of the platform is operatively connected
to
the stabilizer portion 58 by way of a link 184. The link 184 compensates for
changes
in the distance between the movable support portion 56 and stabilizer portions
58.
Moreover, as the stabilizer portion 58 is raised and lowered the platform 170
will
pivot about the horizontal shaft 182 and automatically position the hammer
elements
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152 relative to the transport section 12. In operation, the platform 170 has a
preferred angular range of about 0 to about 25 degrees.
[0046] Preferably, two or more units or modules 150 positioned adjacent each
other in a
side-by-side relation on the platform 170. As shown in Figure 9, the modifying
units
150 are attached to the platform 170 at different elevations. It has been
discovered
that such an arrangement enables the impact zones of the hammer element to
overlap, producing a more uniformly rustic-appearing surface. Preferably, one
of the
primary modifiers 150 is provided with spacers or blocks 178 interposed
between the
upper surface 176 of the platform 170 and the bottom surface of the primary
modifier
housing 162. The two units 150 act in concert with each other and are arranged
so
that they are in a vertically staggered relation so that the impact zones of
the
hammer elements 152 overlap.
[0047] Each preferred hammer element 152 has a shaft 154 having a diameter 155
of
about 1.00 inch (2.54 cm), and includes one end that is operatively connected
to a
drive source such as a pneumatic drive source. The other end of the shaft 154
has
a removable working end 156, which may have one of several differently shaped
impacting surfaces. For example, the impacting surface 156 may be
substantially
flat, hemispherical, or may include a plurality of projections that terminate
in flats and
points. Each hammer element 152 reciprocates, and preferably, each hammer
element has a stroke that varies by as much as 1.50 inches (3.82 cm). This
enables
the hammer elements 152 to work planar surfaces as well as surfaces that have
convexities and concavities. Preferably, each hammer element 152 has an
operational cycle or vibrational speed of approximately 1,500 to 4,000 cycles
per
minute.
[0048] In operation each hammer element 152 independently strikes and impacts
a surface
of a block being moved by the transport section 12 of the machine 10. An
advantage of such independent motion is that the hammer elements 152 are able
to
work and otherwise process block surfaces that include convex and concave
surfaces. Preferred hammer elements 152 are available through Trelawny SPT
Ltd.,
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of 13 Highdown Road, Leamington Spa, Warwickshire, CV31 1XT, United Kingdom.
It is understood, however, that other similar reciprocating devices may be
used
without departing from the spirit and scope of the invention.
[0049] The secondary modifiers 200 may dress or otherwise work the viewable
edges or
arrises of the block to produce irregular edges. A preferred secondary
modifier 200
comprises first and second rotatable drums 202, 204. More specifically, each
drum
202, 204 includes a body having a plurality of outwardly extending teeth 206,
208.
The teeth 206, 208 may be attached to the body in a conventional manner, such
as
welding, or bolting. Alternatively, the teeth 206, 208 may be integral to the
body.
The first rotatable drum 202 is operatively connected to the main frame 20 of
the
machine 10 by a shaft 210 and adjustable pillow blocks 211. Note that the
shaft 210
is substantially parallel to the longitudinal axis of the transport section
12. The first
drum 202 is connected by conventional pulleys 214 and a drive belt 218 to a
motive
source 222 such as an electric or hydraulic motor. As depicted, the first drum
202 is
adjacent the movable support portion 56 so that the teeth 206 of the first
drum
protrude into a gap 92 in the inboard fence 80. As will be understood, the
position of
the first drum 202, relative to the movable support portion 56, is adjustable
closer to
or further away from the movable support portion, which changes the extents to
which the teeth 206 protrude through the gap 92 in the inboard fence 80.
[0050] The second rotatable drum 204 is operatively connected to the crossbeam
or
carriage 120 of the machine 10, also by a shaft 212 and pillow blocks 213. As
with
the shaft 210 that supports the first drum 202, the shaft 212 that supports
the second
drum 204 is substantially parallel to the longitudinal axis of the transport
section 12.
The second drum 204 is connected by conventional pulleys 216 and a drive belt
220
to a motive source 224 such as an electric or hydraulic motor. As depicted,
the
second drum 204 is adjacent the stabilizer portion 58. Note that an upper,
inboard
fence is not needed. The pillow blocks 213 to which the shaft 212 is
connected, may
be adjustable so that the second drum 204 can be adjusted relative to the
stabilizer
portion 58. Although it is possible to arrange the first and second drums 202,
204 so
that their respective teeth are vertically aligned with each other, it is
advantageous to
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position the first and second drums so that the teeth are offset from each
other in the
longitudinal direction of the transport section 12. In operation, the second
drum 204,
which is connected to the stabilizer portion 58 of the transport section 12,
automatically adjusts to differently sized blocks as the stabilizer portion is
raised and
lowered. Preferably, the rotatable drums 202, 204 work several disparate,
viewable
sections of a block before the block reaches the primary modifiers 150. It
will be
understood, however, that the rotatable drums 202, 204 may be positioned at
other
locations on the machine 10 without departing from the spirit and scope of the
invention.
[0051] Another embodiment of a preferred secondary modifier 230 includes one
or more
sub-units or sub-modules 232, 234 that each have one or more hammer elements
236 acting generally perpendicular to the longitudinal axis of the transport
section
12. Each sub-unit or module 232, 234 includes a plurality of hammer elements
236
arranged in a matrix or array. The hammer elements 236 are attached to a
housing
246, which is movably attached to a bracket 254, 256. The bracket 254, 256 may
also be adjustably positioned relative to the transport section 12. Thus, each
sub-
unit or module 232, 234 may be positioned in a plurality of orientations and
positions
relative to the transport section 12.
[0052] Each sub-unit or module may include approximately 1 to approximately 5
hammer
elements. However, it is preferred that each sub-unit or module include
approximately 2 to approximately 4 hammer elements. As with the primary
modifiers
150 discussed above, each preferred hammer element 236 of the secondary
modifiers 232, 234 has a shaft 238 having a diameter 239 of about 1.00 inch
(2.54 cm), and includes one end operatively connected to a drive source such
as a
pneumatic drive source. The other end of the shaft 238 has a removable working
end 240, which may have one of several differently shaped impacting surfaces.
Each hammer element 236 reciprocates and preferably, each hammer element has
a stroke that varies by as much as 1.50 inches (3.82 cm). Preferably, each
hammer
element 236 has an operational cycle or vibrational speed of approximately
1,500 to
4,000 cycles per minute.
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[0053] Preferably, there are two or more sub-units or modules 232, 234 that
can be
adjustably positioned so that they are able to work one or more arrises or
edges of a
block. In operation each hammer element 236 independently strikes and impacts
a
surface of a block being moved by the transport section 12 of the machine 10.
The
sub-units or modules 232, 234 are operatively connected by way of brackets 254
to
locations adjacent the movable support 56 and stabilizer portions 58 of the
transport
section 12, respectively. Preferably, the sub-units or modules 232, 234 work
surfaces of a block after the block passes the primary modifiers 150. However,
it will
be understood that the sub-units or modules 232, 234 may be positioned before
the
primary modifiers 150, if desired. An advantage of such independent motion is
that
the hammer elements 236 are able to work and otherwise process block surfaces
that include convex and concave surfaces. Preferred hammer elements are
available through Trelawny SPT Ltd., of 13 Highdown Road, Leamington Spa,
Warwickshire, CV31 1XT, United Kingdom. It is understood, however, that other
similar reciprocating devices may be used with out departing from the spirit
and
scope of the invention.
[0054] The machine 10 may be provided with an outboard fence or fences 14 that
may be
connected to the movable support 56 and/or the stabilizer portions 58,
respectively.
In a preferred embodiment, a lower outboard fence 14 includes a plate 260 with
an
upper horizontal surface 266 having two ends 262, 264. At each end 262, 264 of
the
plate 260 there is a vertical shaft 268, 270 about which a rotatable element
272, 274
such as a wheel or pulley is mounted. In the space between the end wheels 272,
274, the plate 260 supports a plurality of horizontally oriented arms 276. One
end of
each arm 278 is pivotally connected to vertical shafts 282 extending from the
plate
260, and the other end 280 of each arm 276 is provided with a vertical shaft
284 that
supports a rotatable element 286, such as a wheel or pulley. Each arm 276 is
operatively connected to a spring element 288 that biases the arm 276 in a
predetermined direction towards one side of the plate 260. A belt 290 is
positioned
about the rotatable elements 286 and held in tension due to the effect of the
spring-
biased arms 276. In use, the lower fence 14 is positioned adjacent to and
slightly
above the horizontal surface 266 of the movable support portion 56 so that the
belt
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290 (and the spring biased rotatable elements 286) is able to contact the rear
surfaces of one or more blocks as they are being processed by the machine 10.
Note that the wheeled ends of the arms 280 preferably trail the pivoted ends
278 of
the arms 276.
[0055] The lower fence 14 may include a pair of transversely oriented,
horizontal sleeves
292, 294 that are attached to a lower surface of the plate 260. The sleeves
are
movably mounted to horizontally struts 296, 298 that extend from the movable
support portion 56 of the transport section 12. Each strut includes a jack
screw that
engages internal threads of each sleeve. The jack screws are connected to each
other by sprockets and a chain, with one of the ends of the jack screws
including a
crank arm or similar mechanism. The lower fence 14 may be moved towards and
away from the transport section 12 so as to accommodate different sized
blocks.
[0056] In an alternative embodiment, the lower outboard fence may comprise an
elongated
body that includes first and second ends, a first or horizontal wall, and a
second or
vertical wall. The outboard fence includes one or more rearwardly extending
arms
that may be operatively connected to horizontal struts 296, 298 that are
connected
to the main frame 20 through the movable support portion 56. Preferably, the
outboard fence is movably positionable relative to the horizontal struts 296,
298 so
that the distance between the lower, outboard fence and the inboard fence 80
can
be varied to accommodate blocks having different depths (the z dimension in a
three
dimensional coordinate system).
[0057] The machine may also be provided with an optional upper outboard fence
that
comprises an elongated body that includes first and second ends, a first or
horizontal wall and a second or vertical wall. The upper fence may include a
third
wall that is connected to the first and second walls, and which is angled
relative
thereto. The third wall presents a surface that can guide a block by
contacting an
upwardmost extending rear edge thereof. The upper, outboard fence includes one
or more rearwardly extending arms with upwardly extending posts that may be
operatively connected to horizontal struts by way of tubular brackets. The
horizontal
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CA 02642441 2008-10-30
struts are preferably connected to the carriage or cross beam 120, to which
the
stabilizer portion 58 of the transport section 12 is connected. The position
of the
elongated body may be adjusted in the y and z directions in a three
dimensional
coordinate system to accommodate blocks having different heights and depths.
Optionally, an adjustment mechanism comprising sprockets and a chain is
operatively connected to jack screws in the horizontal struts. This allows the
upper
fence to be moved towards and from the stabilizer portion 58 in a
substantially
parallel manner.
[0058] The foregoing is considered as illustrative only. Furthermore, since
numerous
modifications and changes will readily occur to those skilled in the art, the
exact
construction and operation shown and described is only an example of a
preferred
embodiment. The invention is defined by the following claims.
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