Note: Descriptions are shown in the official language in which they were submitted.
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METHOD OF MANUFACTURING COMPOSITE BOARD
The present invention concerns a method of manufacturing composite board.
Austrian Patent No. 242,581 discloses a method of manufacturing composite
boards
with cores of expanded material. The cores are positioned and introduced
horizontal and coated with soft mortar. The mortar is compacted with a
pivoting
cylinder. Downstream of the cylinder glass cloth is removed from a roll,
forced
down against the top of the mortar, and entrained by the advancing web.
Farther
downstream another coating of mortar is applied loosely to the first coating
and the
glass cloth and compacted with another pivoting cylinder.
The two coats of plastic over the expanded-material core of a composite
manufactured by the method disclosed in Austrian Patent No. 242,581 are
together
much thicker than their framing. They are heavy and inappropriate for such
interior
structures as tiled walls. Such composites are accordingly primarily employed
on
flat roofs and facades. In other words, much more mortar is used to embed and
attach the glass cloth than is needed for interior construction.
German Patent No. 3 423 006 discloses a method of manufacturing light-weight
structural boards. A woven or knitted fabric is stretched tight over an
expanded-
material component and covered with a thin coating of water-resistant mortar.
The
CA 02125557 2004-O1-19
mortar is then smoothed and adheres tight to the fabric. One drawback is that,
while the fabric is being stretched, forces can be exerted between it and the
plastic
that tend to separate the two. Another drawback is that each board is
separately
covered with fabric and coated with mortar. Such discontinuous production is
expensive.
A method of manufacturing similar boards is known from British Patent No.
1,459,575. A mixer pours a base onto a belt that advances at a constant speed.
A
doctor distributes the material to a prescribed thickness. A sealant is
similarly
applied to the base and a surface to the sealant. One drawback to this
approach is
that the thickness of each layer depends on the speed of the belt and on the
skill of
the personnel.
German Patent No. 3 136 935 describes a method of manufacturing board. The
core
of the board essentially comprises layers of adjacent and parallel mineral
fibers. The
fibers are oriented at an angle of 10 to 60° to the surface of the
board. A sheet of
r
aluminum or plastic is applied to the layers of fiber and a coating of
fireproof mortar
to the aluminum or plastic.
One drawback to method is that the board is flexible and accordingly
appropriate
only for wrapping pipes or covering flat and even surfaces.
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German Patent No. 3 444 881 discloses a method of manufacturing board. The
core
is a layer of mineral fiber, glass staple or wadding for example. The core is
more or
less compacted to a fraction of the thickness of the final board. A layer of
mortar is
applied to each side of the core. Glass fibers have been blended into the
mortar.
This board is not very strong and is appropriate only for surfacing solid
concrete
walls.
There is a need therefore, for a method of manufacturing composite board that
will
provide satisfactory insulation of both noise and heat, that will have
satisfactory
mechanical properties, that will be relatively light in weight, smooth, and
flat, and
that is comprised of little material.
Accordingly, the invention relates to a method of producing composite boards,
wherein a core web is coated in a continuous process with a layer of mortar
reinforced with glass fibre fabric or the like, the core web, which is of
plastic foamed
material and/or fibres, balls, chips, strips or pieces of organic and/or
inorganic
materials, being supplied horizontally in the form of an endless web and
hardening
mortar flowing in a liquid state and being distributed on the side of the core
web for
coating, characterised in that a glass fibre fabric web is laid sufficiently
tightly on the
surface of the core web to leave just one adhesive layer between the glass-
fibre fabric
web and the core web, a stripper distributes the mortar so that the layer of
mortar
embeds the web of glass fibre fabric and the still-wet mortar layer then dries
and
sets.
A method of manufacturing composite board comprising a substantially planar
core
having opposite flat sides, a coat of solidified, cement-like mortar disposed
on at
least one of said sides and a layer of cloth embedded within said mortar, said
mortar
and said cloth forming a reinforcement for said core and providing a
supporting
surface for a covering material, said method comprising the steps of
continuously
introducing said core into manufacturing apparatus in a horizontal direction;
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dribbling said mortar in a fluid condition onto one side of said core and
distributing
said mortar over said one side to form a layer; applying an endless web of
cloth in a
substantially tension free condition to said layer of mortar at a speed which
is the
same as a speed of movement of said core in said horizontal direction;
impressing
and embedding said endless web into the mortar layer to provide reinforcement;
wiping off, with a doctor, the mortar which exceeds a prescribed layer
thickness,
thereby forming a lip of mortar upstream of the doctor; sensing the quantity
of
mortar contained in the mortar lip; controlling the rate of mortar dribbled
onto the
core in dependence upon the sensed quantity; cutting a still moist mortar
layer and
embedded cloth to selected lengths; and drying and solidifying the mortar
layer
with the embedded cloth.
Some of the present invention s advantages will now be described. The core can
be
of expanded material alone or of expanded material with a layer of fibers,
glass
wadding for example, with a layer of beads, chips, flakes, fragments, etc. of
organic
or inorganic materials, or with an extruded layer of more expanded material.
Since
the core is in the form of a web and the mortar is preferably dribbled onto it
at a rate
that matches the speed it is advancing at, the
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t. glass cloth can be embedded in the mortar while it is still
2 moist and there will be no internal stress to buckle the
3 board. Once the mortar is dry, accordingly, the board will
4 be strong and will satisfactorily insulate both heat and
noise. It can be employed not only to surface existing
6 walls, but as a wall in its own right. It can also be
7 plastered, papered, or tiled.
8
9 One particular advantage is that a layer of reinforced mortar
can be applied to the smooth surface of the core to produce
11 boards that are especially practical in the construction
12 industry, for erecting partitions for example. Such
13 partitions will be strong enough to support tiles,
14 coverings, and fixtures.
16 It is of essential significance that, although the mortar on
17 one side of the core is very fluid while. it is being applied
18 and accordingly very thin, it will dry extremely strong. Tt
19 has been demonstrated practical for the mortar to be applied
fluid enough to spread 22 to 28 cm as measured with the
21 Wicker cup in accordance with DIN 1060.
22
23 It is practical in the foregoing event for the liquid mortar
24 to flow onta the core between two close-together cylinders
that preferably rotate in the same sense. The cylinders keep
26 the mortar homogeneous enough to harden uniformly and only
27 once it has spread. The cylinders can also be spaced and
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212ja~7
rotated to precisely regulate the flow of the mortar.
3 The flow of mortar can for example be regulated by opening
4 and closing a device that comprises the aforesaid cylinders.
6 Compacting the layer of beads, chips, flakes, fragments, etc.
7 of organic or inorganic materials is also practical. This
8 procedure will result in a core essentially as thick as the
9 finished board and strong enough to be exposed to static or
dynamic stress of the extent to be expected when employed for
11 the purposes discussed herein.
12
13 It is of advantage when the layer of beads, chips, flakes,
14 fragments, etc. of organic or inorganic materials is coated
with an expanded extrudate for the extrudate to permeate or
16 bind the beads etc. The result will be a core or sandwich of
17 organic or inorganic materials wherein at least one surface
18 of the mineral fibers, which are not particularly strong
~I9 mechanically, will be in contact with the more durable and
homogeneous expanded extrudate.
21
22 The expanded extrudate can be polystyrene or glass, a
23 recycled bulk or expanded extrudate, or a wood-bonding sheet.
24 Other similar materials can also be employed. Some examples
are recycled bulk or expanded and compressed recycled
26 materials, expanded polyurethane, and such solid blends as
27 wood-bonding and similar materials. It is essential in this
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event as well for the expanded-material core to be provided at some point with
a
rigid and reinforced sandwich structure that will render it not only fireproof
but also
able to have tiles for example cemented or otherwise fastened to it or to be
plastered,
wallpapered or painted.
It is of advantage for the layer of reinforced mortar to be very thin, as thin
as 0.2 mm
for example. There is on the other hand essentially no upper limit.
To ensure relaxed but uniform embedding of the glass cloth, it can be
introduced by
way of a tension equalizer.
The glass cloth can be woven or non-woven. Fabrics of aramid, polyester, and
similar materials can also be employed when sufficiently stable. Metal gauze,
copper or stainless steel for example, can also be employed.
Embodiments of the present invention will now be specified by way of example
with reference to the drawings, wherein
Figure 1a illustrates a production line for manufacturing a continuous core,
Figure 1b illustrates another version of a production line for manufacturing a
continuous core,
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2~2 ~~5 i
a- Figure 2 illustrates machinery for manufacturing board out of
2 a continuous core,
3
4 Figure 3a is a cross-section through a section of board with
a core of expanded material,
6
7 Figure 3b is a cross-section through a section of board with
8 a core of mineral staple or wadding,
9
Figure 3c is a cross-section through a section of another
11 type of board with a core of mineral staple or wadding, and
12 Figure 3d is a cross-section through a section of still
13 another type of board with a core of mineral staple or
14 wadding.
16
17 The creation of a continuous core 2 will now be discussed
18 with reference to Figure la. An extruder 31 extrudes a layer
19 of expanding extrudate 21 onto a
roller pavement 30. A fiber distributer 32 deposits staple '
21 or wadding 22 or 22' onto the advancing expanding extrudate
22 21. The staple or wadding can be mineral or plastic fiber,
23 sheep's, llama's, or other animal wool, fiber from recycled
24 clothing etc. or a combination thereof. Fiber distributer 32
can deposit staple or wadding 22 or 22' onto expanding
26 extrudate 21 loose or tight.
27
-
The core can be a core 2 "' with two layers instead of a
2 core 2 with one layer. Core 2 " ' can comprise a layer of
3 expanding extrudate 21 and a layer of staple or wadding 22 or
4 22'. Another layer of expanding extrudate 21 can be extruded
over staple or wadding 22 or 22', producing a core 2 " " in
6 the form of a sandwich with a layer of staple or wadding
7 between two outer layers of expanding extrudate.
8
9 Another type of core is illustrated in Figure lb. Mineral
or animal staple or wadding 22 or 22' is compressed into a
11 web by a fiber compactor 32'. Upon leaving the compactor,
12 staple or wadding 22 or 22' will be relieved of pressure and
13 expand again, and individual fibers will project out of the
14 upper surface of the core. When an extruder or extruders
31' and 32' extrude expanding extrudate 21 onto this loosely
16 compacted core of staple or wadding 22 or 22', the projecting
17 fibers enter into an intimate bond with the extrudate. The
I8 result is a continuous core 2 " " that rests on pavement 30'
19 and exhibits the positive properties of a hardened expanding
extrudate 21 in conjunction with staple or wadding 22 or 22','
21 specifically satisfactory insulation of noise and heat along
22 with static and dynamic endurance.
23
24 Fiber distributer 32 or fiber compactor 32' can also compact
the staple or wadding 22 or 22'in a core 2 " or 2 " ' until
26 the surface is smooth and resistant.
27
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222W 7
'~ Core 2, 2 " , 2 " ', or 2 " " can be further processed in the
2 equipment illustrated in Figure 2. Composite board can be
3 produced therein from a continuous core 2. The core is
4 deposited on a driven roller pavement and can be trimmed into
separate panels or sections. A mortar hopper 3 is positioned
6 above a colander 4. Between colander 4 and the surface of
7 core 2 is a flow regulator 5. Flow regulator 5 comprises two
~8 narrowly separated cylinders 105 and 106 that rotate in the
9 same sense. Cylinders 105 and 106 are jacketed with water-
repellent rubber with a Shore hardness of W 1357. Their
11 diameter is approximately 200 mm. They are synchronized by a
I2 variable-speed motor.
13
14 The viscosity of the mortar flowing out of hopper 3 and
through colander 4 and flow regulator 5 is extremely
16 critical. The mortar is a shallow-bed mortar based on cement
17 and containing plastic to render the hardened mortar more
18 elastic. The mortar also contains fillers to improve its
19 thixotropic properties, which must be maintained precisely
constant. Especially appropriate for this purpose are
21 powdered quartz or chalk for example. Recipes for various
22 purposes can be obtained from specialized firms.
23
29 The spread of the mortar is measured in a frustroconical
Wickert ring 40 mm high and with an ugper inside diameter of
26 79 mn and a lower inside diameter of 65 mm resting on a
27 Hegmann surface in accordance with DIN 1060 (EN 196). The
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212557
~w diameter of the pancake should range between 22 and 28cm and
2 preferably between 23 and 27cm.The thready consistency of the
3 mortar is homogenized or maintained by the rotation of
4 cylinders 105 and 106. The mortar flows onto core 2 through
the gap between the cylinders and is evenly distributed over
6 the surface of the core by a doctor 6 downstream of the
7 cylinders.
8
9 Downstream of doctor 6 a continuous web 7 of woven or non-
woven glass cloth is introduced practically free of stress,
11 subject, that is, only to its_own weight and advancing at the
12 same speed as core 2. The cloth is obtained from a roll 18
13 and travels through a tension equalizer 19 of a type in
14 itself known from textile engineering. A beam 8 lays web 7
just (approximately 2 mm) above core 2 and accordingly
16 slightly embeds it in layer 9 of mortar. The mortar is
17 forced against the bottom of the web and between its
18 interstices, ensuring satisfactory adhesion in that the
19 distance from web 7 of woven or non-woven glass cloth is
such that precisely one more layer of adhesive is maintained
21 between the cloth and the upper surface of the web.
22
23 Another doctor 10 scrapes excess mortar off the upper
24 surface of the cloth and smoothes it into a layer that not
only embeds web 7 of woven or non-woven glass cloth but also
26 rises slightly above it, leaving the cloth as a
27 reinforcement in the still wet mortar 9, which nevertheless
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contacts the surface of the web only by ~ ~ ~of~a thin layer
2 of mortar. The excess mortar 11 scraped off by second doctor
3 10 creates a downstream demarcation in the form of a lip 12
4 that can be detected by an optico-electronic or capacitative
sensor 13.
6
7 When lip 12 moves too far from second doctor 10, sensor 13
8 emits a signal to a data processor 14, which reduces the flow
9 through flow regulator 5 by decelerating cylinders 105 and
106.
11
12 When lip 12 moves back toward second doctor 10., data
13 processor 14 will reestablish the speed of the cylinders, and
14 flow regulator 5 will emit more mortar.
16 The layer 9 of mortar on care 2 downstream of second doctor
17 10 is accordingly highly uniform.
18
19 Core 2 now arrives below a lengthing position 15, where a
knife blade 15' cuts through the still moist layer 9 of
21 mortar and its reinforcing web 7 of woven or non-woven glass
22 cloth and optionally through core 2 " , 2 "'. or 2 " " as
23 well, creating an edge at regular intervals for edge-to-edge
24 modular mounting or at other convenient points when the board
is to be continuous. Core 2 is now dried and solidified
26 along with its glass-reinforced layer 9 of mortar in a kiln
27 16. The reinforced layer 9' of mortar is accordingly firmly
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21~~5~ r~
anchored into 2' , 2" , 2" ' , or 2" " . If the core is to be
2 coated on only one surface, the composite board can be
3 employed as is. Usually, however, the core is coated on both
4 sides. The core coated on one side is accordingly returned
upside-down to the upstream end of roller pavement 1, and the
6 aforesaid procedure is repeated. Composite board with a core
7 of mineral fiber or of any other organic or inorganic
8 materials can be produced as hereintofore specified.
9 Appropriate are various in-themselves known mixtures of
cement, water, and plastic that can be made into shallow-bed
11 mortars. Although their recipes could be specified, they
12 will not be herein because they do not constitute part of the
13 invention. Such shallow-bed mortars resemble the usually
14 water-resistant mortars employed for laying tile.
16 The thickness of the core is relatively uncritical. It can
17 be between a few millimeters and a few centimeters, between
18 20 and 100 mm for example, depending on its purpose. Layer 9
19 of mortar will generally be applied as economically as
possible, just enough to cover the glass cloth.
21
22 Figures 3a through 3c illustrate various composite boards of .
23 types that can be produced in accordance with the present
24 invention.
26 The core 2' of expanded extrudate 21 illustrated in Figure 3a
27 has a layer 9' of mortar reinforced with an embedded web 7 of
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1 r non-woven glass cloth on each s~~~ ~ ~
woven o
2
3 The board illustrated in Figure 3b on the other hand has a
4 core 2" of mineral or animal staple or wadding 22 or 22'
with a layer 9' of mortar reinforced with an embedded web 7
6 of woven or non-woven glass cloth on each side.
7
8 The core 2 " ' illustrated in Figure 3c combines mineral or
9 animal staple or wadding 22 or 22' with a layer of expanded
extrudate. It is also coated on each side with a layer 9' of
11 mortar reinforced with an embedded web 7 of woven or non-
12 woven glass cloth.
13
14 The core 2" " of the composite board illustrated on Figure
3d is particularly practical. A layer of mineral or animal
16 staple or wadding 22 or 22' is sandwiched between two coats
17 of expanded extrudate 21. The fibers project like those
18 illustrated in Figure 3c into each coat of extrudate. The
19 result is a very intimate and solid bond between mineral or
animal staple or wadding 22 or 22' and the coats of expanded
21 extrudate 21. The two coats prevent the fibers from
22 escaping.
23 .
24 Escape can be further inhibited by mixture with wool or by
wool alone.
26
27 It is also possible to chemically coat or impregnate each
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r
~-~~~ individual fiber. Board made of chemically treated fiber
2 does not need to be coated with expanded extrudate, mortar,
3 or cloth. A coat 9' of mortar reinforced with an embedded
4 web 7 of woven or non-woven glass cloth can also be applied
to each side of such a highly stable core 2 " "
6
7 One particular advantage of all four composite boards
8 specified herein is the common interface between the mortar
9 and the glass cloth. This common interface ensures that the
glass cloth will be intimately secured to the care by the
11 mortar and that the mortar will have a surface appropriate
12 for papering, tiling, etc.
13
14
16
17
18
19
21
22
23
24
26
27
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