ACOUSTICAL SUPPORT PANEL

PANNEAU SUPPORT INSONORISANT

English Abstract

The acoustical support panel according to the invention comprises a
membrane of resilient material, such as one obtained with shredded used tires,
which is laminated on a base of compression resistant cellulose fibers. This
panel has shown a noted increase of insulation from impact and aerial noises.
It has an excellent dimensional stability and high resistance to
compression.

Claims

CLAIMS
1. An acoustical support panel comprising
a membrane of resilient material, and
a base of compression resistant cellulose fibers,
said membrane being laminated on said base under conditions to
constitute said panel.
2. Acoustical support panel according to claim 1, wherein said membrane
is made of resilient rubber material.
3. Acoustical support panel according to claim 2, wherein said resilient
rubber material comprises recycled tire material.
4. Acoustical support panel according to claim 1, wherein said membrane
of resilient material has a thickness between about 0.1 and 0.25 inch.
5. Acoustical support panel according to claim 4, wherein said membrane
of resilient material has a thickness of about 0.14 inch.
6. Acoustical support panel according to claim 1, wherein said membrane
of resilient material has a density between 18 and 30 lbs./ft3.
7. Acoustical support panel according to claim 6, wherein said membrane
of resilient material has a density of about 22 lbs./ft3.
8. Acoustical support panel according to claim 1, wherein said membrane
of resilient material has a retention (50 Kpa load) according to ASTIM D-1055
of about 50% and a retention (100 Kpa load) according to ASTM D-1055 of
about 40%.
9. Acoustical support panel according to claim 1, wherein said base is
made of wood fibers.
10. Acoustical support panel according to claim 1, wherein said base has a
thickness between about 0.3 and about 1.0 inch.
11. Acoustical support panel according to claim 10, wherein said base has
a thickness of about 0.4 inch.
12. Acoustical support panel according to claim 1, wherein said base has a
compression strength at 10% deformation of about 45 lbs./in2.
13. Acoustical support panel according to claim 1, wherein said base has a
linear expansion of about 0.08%. and a water absorption of about 5% P/V..
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14. Acoustical support panel according to claim 1, wherein said base has a
transverse load at rupture of about 12 lbs
15. Process for the manufacture of an acoustical support panel which
comprises providing a membrane of resilient material, providing a base of
compression resistant cellulose fibers, and laminating said membrane on said
base under conditions to constitute said panel.
16. An acoustical system for mounting a wood flooring over a structure
consisting of joist means, board means over said joist means, a layer of
concrete over said board means, an acoustical support panel according to
claim 1 over said concrete, wooden joists over said support panel, and said
wood flooring mounted over said wooden joists.
17. An acoustical system for mounting a wood flooring over a concrete
base, which comprises an acoustical support panel according to claim 1
mounted with the membrane of resilient material at the bottom, wooden laths
spacedly distributed in parallel fashion over said support panel, longitudinal
members made of same material as said acoustical support panel and aligned
over said support panel between said laths, and adapted to receive said wood
flooring.
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Description

CA 02363828 2001-11-23
ACOUSTICAL SUPPORT PANEL
The present invention relates to a panel, and more particularly to an
acoustical support panel and a process for manufacturing same. More
specifically, the present invention is concerned with an acoustical support
panel which can be obtained by laminating a membrane of resilient material
such as rubber, on a base of compression resistant cellulose fibers, and the
use
of said panel to provide a specific support for the mounting of a wood
10 flooring, tile, vinyl, carpet or installing a rug, for example.
(b) Description of Prior Art
In modern construction, especially in homes and apartment buildings
as well as in office buildings, no efforts should be spared to ensure that the
floors and ceilings are acoustically insulated. In practice, a slab of
concrete
15 with a substantial thickness can provide some acoustical insulation,
however
this is far from being satisfactory and economical.
A number of U.S. Patents describe acoustical materials which are
capable of absorbing sounds, however to Applicants knowledge none of them
teach an acoustical support panel which absorbs sounds with a high degree of
20 satisfaction and at a reasonable cost.
U.S. 2,542,428 describes a sound-deadening structure including a sheet
of rubber material formed with projections on one face thereof, and a layer of
flowable setting material having the projections embedded therein.
U.5. 2,802,764 is concerned with an acoustical material consisting of a
25 slab of glass fibers covered with an impervious resinous membrane which
shrinks when subjected to heat.
U.S. 2,874,796 describes a method of fabricating a sound absorbing
unit having artificial openings therein, by applying a boric acid solution to
a
surface of the formed body.
30 U.S. 3,961,682 describes a sound-absorbing wall element including a
plurality of layers, one of them being made from shredded used tires. The
other layer may include a sound absorbing material such as mineral wool.
1

CA 02363828 2001-11-23
U.S. 4,253,543 describes a device for the absorption of airborne sound
which includes an air permeable base layer and an impervious membrane
applied to the base layer. This patent does not disclose a rubber membrane
laminated on a cellulose base.
U.S. 4,570,748 discloses a volume-changing resonator in the form of a
sound silencer which has a surface made of rubber.
U.S. 4,709,781 concerns a sound-damping and heat-insulating
composite plate which includes a porous core made of rubber granules or
scrap, which is disposed between two layers of metals.
U.S. 4,989,688 describes an acoustical panel consisting of a rigid
frame in which there is an insulation medium, such as fiberglass, cellulose,
and the like. The outer surfaces of the cell grid are covered with a skin or
screen mesh for confining the loose discrete insulation.
It will therefore be seen that the prior art does not teach an acoustical
support panel which is easy and inexpensive to produce, and which at the
same time is highly efficient.
It is an object of the present invention to provide an acoustical support
panel which is specifically designed for mounting wood floorings, ceramic,
tile, carpet and the like.
It is another object of the present invention to provide an acoustical
support panel which shows a noted increase of insulation from impact noises
and aerial noises.
It is another object of the present invention to provide a simple method
for preparing acoustical support panels which can be used in the construction
of homes, office buildings and the like.
These and other objects of the present invention may be achieved by
providing an acoustical support panel which comprises a membrane of
resilient material, and a base of compression resistant cellulose fibers, the
membrane being laminated on the base under conditions to constitute the
panel.
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CA 02363828 2001-11-23
The membrane is preferably made of resilient rubber material. In
practice, it has been found that a membrane consisting of shredded used tires
is entirely satisfactory.
The membrane may be of any suitable thickness as will be appreciated
5 by one skilled in the art. However, in practice it has been found that the
membrane may be between about 0.1 and 0.25 inch, preferably 0.14 inch, it
being understood that any value outside the above range would be acceptable,
without departing from the scope and spirit of the present invention, provided
the desired insulation can be obtained.
Another property of the membrane is its density. It has been found that
it is highly desirable, although not essential, that the density be between
about
18 and 30 lbs./ft3, preferably about 22 Ibs./ft3.
In accordance with another embodiment, the membrane of resilient
material should preferably have a retention (50 Kpa load) according to
ASTMD-1055 of about 50% and a retention (100 Kpa load) according to
ASTMD-1055 of about 40%.
The base of compression resistant cellulose fibers is preferably made
of wood fibers. Although its thickness may vary to a large extent as will be
appreciated by one skilled in the art, it is normally between about 0.3 and
about 1.0 inch thick, preferably about 0.4 inch.
A preferred property of the base is a compression strength at 10%
deformation of about 45 lbs./in2, although this value may vary to a large
extent
again as will be appreciated by one skilled in the art.
Another property is the water absorption of the base which may be set
at about 5% P/V although any other suitable value below 10% P/V is within
the scope of the present invention.
Another preferred property is the linear expansion of the base which
may be set at about 0.08% although any other suitable value is within the
scope of the present invention.
30 Finally, another preferred property of the acoustical support panel
according to the invention is a transverse load rupture which should be about
12 lbs.
3

CA 02363828 2001-11-23
In accordance with another embodiment, the acoustical support panel
according to the invention may be manufactured by providing a membrane of
resilient material, providing a base of compression resistant cellulose
fibers,
and laminating the membrane on the base under conditions to constitute the
panel.
The invention is illustrated by means of the annexed drawings in which
FIGURE 1 is a cross-section view of an acoustical support panel
according to the invention;
FIGURE 2 is a schematic illustration of the mounting of a hardwood
flooring utilizing an acoustical support panel according to the invention; and
FIGURE 3 is a schematic illustration of another possible arrangement
for a hardwood flooring provided with an acoustical support panel according
to the invention.
FIGURE 4 is an enlarged view of a resilient channel to mount the I-
beams illustrated in FIGURE 2.
As shown in FIGURE l, an acoustical support panel according to the
invention comprises a membrane a of shredded used tires which is laminated
on a base b of compression resistant wood fibers. Lamination is of course
achieved by using a glue, the choice of which is entirely left to one skilled
in
the art.
With reference more particularly to FIGURE 2, which illustrates a
hardwood floor mounting according to the invention, it will be seen that there
is first provided a plurality of I-beams 3 or other joists type, two of which
are
shown in the drawings, and each is 14 inch high. Of course, the structure and
size of the I-beams or other joists type can vary depending on the choice of
the
designer of the floor structure.
Underneath the beams, there are mounted two sheets of gypsum 7, 9,
5/8 inch thick each. These two sheets may constitute the ceiling of a room
below. Between the base of I-beams 3 and the two sheets of gypsum 7,9, there
are provided resilient channel bars 10 which are fixed by means of a screwing
device 10a extending through gypsum sheets 7,9 into I-beams 3 at the base
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CA 02363828 2001-11-23
thereof. These channel bars 10 are used to hold I-beams 3 and to absorb
shocks produced by sonic vibrations.
Above beams 3, there is first provided a board 11 of Aspenite~ for
example, or tongue and groove plywood, 5/8 inch thick, a layer of concrete 13,
S 1 %z inch thick, an acoustical support panel 1 S according to the invention,
bearing joist 17 and finally floorboards 19. Finally, it will be realized that
a
cellulose, glass, or rock wool or the like insulating material 21 well known
to
those skilled in the art, fills the space between I-beams 3 above sheets of
gypsum 7,9 and below the board of Aspenite ° . This arrangement is of
course
10 mounted in a manner well known to those skilled in the art.
It was found that with the insertion of an acoustical support panel 15
according to the present invention, there is a noted increase of the
insulation
capacity from impact and aerial noises to FIIC = SS, as compared to known
insulation techniques.
15 Turning now to FIGURE 3, it will be seen that the acoustical panel
according to this embodiment is intended to be mounted on a base 23 of light
concrete, preferably 8 inches thick. The acoustical panel 25 is the same as
the
one illustrated in Figure 1, except that the order is reversed in that
membrane a
of shredded used tires is at the bottom and is placed directly on light
concrete
20 base 23, while layer b of wood fibers is at the top as shown. Laths 27,
preferably 7/16 inch thick (slightly less thick than panel 25) are placed 6
inches apart over panel 25 as shown. Then pieces of panel 25, 6 inches wide,
referred to as members 29, with layer a oriented at the top, are glued in
known
manner over panel 25 between laths 27, as shown. This arrangement gives a
25 FIIC of 56. The same results have been noted as in the arrangement of
FIGURE 2, with respect to impact and aerial noises.
A typical acoustical panel according to the invention is described in the
following table, wherein the panel is 4' x 8' x 17/32".
S

CA 02363828 2001-11-23
PHYSICAL PROPERTIES
Method norm Value
Rubber
S 1 Composition :
recycled tires
1 Thickness ASTM D-1037 0.138"
1 Density ASTM D-1037 22 lbs./ft3
1 Retention
(load of 50 Kpa) ASTM D-1055 50
(load of 100 Kpa) ASTM D-1055 40
Wood fiber panel
1 Composition : wood
fiber
1 Thickness ASTM D-1037 0.409"
1 Water
absorption ASTM C-209 5 % P/V max
1 Compression strength
atl0% deformation ASTM C-165 451bs./in2
1 Linear
expansion ASTM C-209 0.08
1 Transverse
load at rupture ASTM C-209 12 lbs.
The above invention is not limited to the above embodiment except as
defined in the appended claims.
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Representative Drawing