U.S. patent application number 11/589457 was filed with the patent office on 2008-05-01 for acoustic insulator and method of manufacturing same.
This patent application is currently assigned to Lear Corporation. Invention is credited to Terence Connelly, Edward Simon.
Application Number | 20080099278 11/589457 |
Document ID | / |
Family ID | 39328791 |
Filed Date | 2008-05-01 |
United States Patent
Application |
20080099278 |
Kind Code |
A1 |
Simon; Edward ; et
al. |
May 1, 2008 |
Acoustic insulator and method of manufacturing same
Abstract
An acoustic insulator includes a first layer having an outer
surface and an inner surface and a second layer having an outer
surface and an inner surface. The outer layer of the second layer
is disposed adjacent to and engaging the inner surface of the first
layer. The first layer and the second layer form at least one
protrusion extending outwardly from the acoustic insulator.
Inventors: |
Simon; Edward; (Canton,
MI) ; Connelly; Terence; (Plymouth, MI) |
Correspondence
Address: |
INTERNATIONAL AUTOMOTIVE COMPONENTS GROUP, LLC;c/o MACMILLAN, SOBANSKI &
TODD, LLC
ONE MARITIME PLAZA, FIFTH FLOOR, 720 WATER STREET
TOLEDO
OH
43604
US
|
Assignee: |
Lear Corporation
|
Family ID: |
39328791 |
Appl. No.: |
11/589457 |
Filed: |
October 30, 2006 |
Current U.S.
Class: |
181/293 |
Current CPC
Class: |
B32B 27/12 20130101;
G10K 11/172 20130101; B32B 3/28 20130101; B60R 13/0815
20130101 |
Class at
Publication: |
181/293 |
International
Class: |
E04B 1/82 20060101
E04B001/82 |
Claims
1. An acoustic insulator comprising: a first layer having an outer
surface and an inner surface; and a second layer having an outer
surface and an inner surface, said outer layer of said second layer
disposed adjacent to and engaging said inner surface of said first
layer, said first layer and said second layer having a protrusion
extending outwardly from said acoustic insulator.
2. The acoustic insulator according to claim 1, wherein said first
layer and said second layer have a plurality of protrusions
extending outwardly from said acoustic insulator.
3. The acoustic insulator according to claim 2, wherein said
protrusions are spaced evenly apart from one another throughout the
extent of said acoustic insulator.
4. The acoustic insulator according to claim 1, wherein said
protrusion is shaped generally in the shape of an inverted
bell.
5. The acoustic insulator according to claim 1, wherein said first
layer is a needled non-woven fiber pad.
6. The acoustic insulator according to claim 1, wherein said first
layer is formed from at least one of cotton, hemp, wool, silk,
jute, polyester, polypropylene, nylon, glass, ceramic, and
polyethylene terephthalate.
7. The acoustic insulator according to claim 1, wherein said first
layer is formed of a combination of polyethylene and polyethylene
terephthalate fibers
8. The acoustic insulator according to claim 1, wherein said second
layer is generally air impermeable.
9. A combined acoustic insulator and supporting component
including: a supporting component having a surface; and an acoustic
insulator including a first layer having an outer surface and an
inner surface and a second layer having an outer surface and an
inner surface, said outer layer of said second layer being disposed
adjacent to and engaging said inner surface of said first layer,
said first layer and said second layer having a protrusion
extending outwardly from said acoustic insulator into engagement
with said surface of said supporting component.
10. The acoustic insulator according to claim 9, wherein said
supporting component is a vehicle dash panel.
11. The acoustic insulator according to claim 9, wherein said
supporting component is a vehicle wheel well.
12. The acoustic insulator according to claim 9, wherein said first
layer and said second layer have a plurality of protrusions
extending from said acoustic insulation panel into engagement with
said surface of said supporting component.
13. The acoustic insulator according to claim 12, wherein the size,
shape and quantity of said plurality of protrusions is selected so
as to cancel specific frequencies of noises and vibrations
generated by said supporting component.
14. The acoustic insulator according to claim 12, wherein said
protrusions are spaced evenly apart from one another throughout the
extent of said acoustic insulation panel.
15. The acoustic insulator according to claim 9, wherein said
protrusion is shaped generally in the shape of an inverted
bell.
16. The acoustic insulator according to claim 9, wherein said first
layer is a needled non-woven fiber pad.
17. The acoustic insulator according to claim 9, wherein said first
layer is formed from at least one of cotton, hemp, wool, silk,
jute, ramie, sisal, polyester, polypropylene, nylon, glass, and
polyethylene terephthalate.
18. The acoustic insulator according to claim 9, wherein said first
layer is formed of a combination of polyethylene and polyethylene
terephthalate fibers
19. The acoustic insulator according to claim 9, wherein said
second layer is generally air impermeable.
20. A method of manufacturing an acoustic insulator-comprising the
steps of: (a) providing a fiber layer; (b) extruding a film layer
onto the fiber layer; and (c) molding the fiber layer and film
layer to form an acoustic insulator having at least one protrusion
extending outwardly therefrom.
Description
BACKGROUND OF THE INVENTION
[0001] This invention relates in general to acoustical insulators,
such as for use in vehicles. In particular, this invention relates
to an improved structure for such an acoustical insulator and to a
method of manufacturing same.
[0002] Acoustic insulators are used in many different applications
for reducing the amount of airborne noise that is transmitted to
the interior of the vehicle from one side of the panel to the other
and reducing noise generated from vibration of the panel. For
example, acoustical insulators are often used in a variety of
vehicles, including automobiles, airplanes, trains, and the like,
to minimize the amount of exterior noise that is transmitted to the
interior of the vehicle. Similarly, acoustical insulation panels
are often used in a variety of buildings and other static
structures to minimize the amount of ambient noise that is
transmitted to the interior of the building.
[0003] A variety of acoustical insulators structures are known in
the art. In many instances, the acoustical insulators are formed
from laminates and laminated composites. It is usually desirable
that such acoustical insulators have relatively high strength and
rigidity characteristics and be relatively resistant to degradation
from exposure to heat and moisture. When such acoustical insulators
are used in vehicle applications, it is further desirable that they
be relatively inexpensive and lightweight. Thus, it would be
desirable to provide an improved structure for an acoustical
insulator, and a method of manufacturing same, that satisfies all
of these desirable characteristics.
SUMMARY OF THE INVENTION
[0004] This invention relates to an improved structure for an
acoustical insulator and to a method of manufacturing same. The
acoustic insulator includes a first layer having an outer surface
and an inner surface and a second layer having an outer surface and
an inner surface. The outer layer of the second layer is disposed
adjacent to and engaging the inner surface of the first layer. The
first layer and the second layer form at least one protrusion
extending outwardly from the acoustic insulator.
[0005] This invention also relates to a combined acoustic insulator
and supporting component including a first layer having an outer
surface and an inner surface and a second layer having an outer
surface and an inner surface. The outer layer of the second layer
is disposed adjacent to and engaging the inner surface of the first
layer. The first layer and the second layer form at least one
protrusion extending from the acoustic insulator such that the at
least one protrusion engages a surface of the supporting
component.
[0006] The invention further relates to a method of manufacturing
an acoustic insulator including providing a fiber layer and
extruding a film layer onto the fiber layer. The fiber layer and
film layer are then molded to form an acoustic insulator having at
least one protrusion extending outwardly therefrom.
[0007] Various objects and advantages of this invention will become
apparent to those skilled in the art from the following detailed
description of the preferred embodiment, when read in light of the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a perspective view of a prior art acoustic
insulator and a supporting component.
[0009] FIG. 2 is an enlarged sectional elevational view of portions
of the prior art acoustic insulator and the supporting component
illustrated in FIG. 1.
[0010] FIG. 3 is a perspective view of an acoustic insulator and a
supporting component in accordance with this invention.
[0011] FIG. 4 is an enlarged sectional elevational view of portions
of the acoustic insulator and the supporting component illustrated
in FIG. 3.
[0012] FIG. 5 is a schematic elevational view of an apparatus for
manufacturing the acoustic insulator illustrated in FIGS. 3 and 4
in accordance with the method of this invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0013] Referring now to the drawings, there is illustrated in FIG.
1 a portion of an acoustic insulator, indicated generally at 10,
that is conventional in the art. The prior art acoustic insulator
10 is shown adjacent to a supporting component 12, which may be any
vehicular component, such as a dash panel, wheel well, roof,
package shelf, door panel, trunk floor, engine compartment wall,
and the like. As illustrated, the supporting component 12 is a
passenger side dash panel, and the prior art acoustic insulator 10
is disposed adjacent to a side of the passenger side dash panel
such that the prior art acoustic insulator 10 is hidden from view
from the interior of the vehicle by the instrument panel. The
illustrated prior art acoustic insulator 10 and the supporting
component 12 have a planar contour, but can be formed having any
desired non-planar contour. The illustrated prior art acoustic
insulator 10 can be molded to have a contour that corresponds to
the contour of the supporting component 12, as shown.
[0014] The structure of the prior art acoustic insulator 10 is
illustrated in detail in FIG. 2. As shown therein, the prior art
acoustic insulator 10 includes a first layer 14 having an outer
surface 16 and an inner surface 18. The first layer 14 may be any
needled non-woven fiber pad and may be formed of cotton,
polyethylene, or any combination thereof.
[0015] The prior art acoustic insulator 10 also includes a second
layer 20 having an outer surface 22 and an inner surface 24. As
best shown in FIG. 2, the outer surface 22 of the second layer 20
is disposed adjacent to and engages the inner surface 18 of the
first layer 14. The second layer 20 may be formed from any desired
material that functions as a barrier layer that does not allow the
flow of air therethrough. For example, the second layer 20 may be
formed from a polymer material, such as polyethylene.
[0016] The prior art acoustic insulator 10 also includes a third
layer 26 having an outer surface 28 and an inner surface 30. As
best shown in FIG. 2, the outer surface 28 of the third layer 26 is
disposed adjacent to and engages the inner surface 24 of the second
layer 20. The inner surface 30 of the third layer 26 is disposed
adjacent to and engages the outer surface of the supporting
component 12. The third layer 26 is preferably a fiber pad and may
be formed of cotton, polyethylene, or any combination thereof and
may include resinated fiber. The third layer 26 is air permeable
and supports the first layer 14 and the second layer 20 on the
supporting component 12 in a spaced apart manner. Supporting the
first layer 14 and the second layer 20 in a spaced apart manner is
desirable because contact between the second layer 20 and the
supporting component 12 may produce additional noise and
vibration.
[0017] Airborne noise may be transmitted through supporting
component 12 from the exterior of the vehicle due to noise radiated
from the engine, exhaust and tires. Noise may also be generated by
vibration of the supporting component 12 transmitted from any other
portion of the vehicle (not shown). The sound waves from the noise
sources may be attenuated by the first layer 14 and the second
layer 20 and the third layer 26. The third layer 26 may also reduce
such vibration from transferring to the first layer 14 and the
second layer 20, such that the acoustic insulator 10 does not
amplify such vibration.
[0018] Referring now to FIG. 3, there is illustrated a portion of
an acoustic insulator, indicated generally at 40, in accordance
with this invention. The acoustic insulator 40 is shown adjacent to
a supporting component 42, which may be embodied as any component
provided on or within a conventional structure. For example, the
supporting component 42 may be a vehicular component, such as a
dash panel, wheel well, roof, package shelf, door panel, trunk
compartment or floor, engine compartment wall, and the like.
Alternatively, instead of being positioned adjacent to the
supporting component 42 as shown, the acoustic insulation panel 40
may be positioned within some or all of the supporting component
42. For example, the acoustic insulation panel 40 may be positioned
within a headliner, package shelf covering, door panel lining or
covering, non-load bearing trunk compartment liner, engine
compartment liner, and the like. Furthermore, the supporting
component 42 may be embodied as a portion of a building or other
static structure. The illustrated acoustic insulator 40 and the
supporting component 42 have a planar contour, but can be formed
having any desired non-planar contour. The illustrated acoustic
insulator 40 can be molded to have a contour that corresponds to
the contour of the supporting component 42, as shown in FIG. 3 and
described in detail below.
[0019] In the illustrated embodiment, the supporting component 42
is a passenger side dash panel, and the acoustic insulator 40 is
disposed adjacent to the interior side of the passenger side dash
panel such that the acoustic insulator 40 is hidden from view from
the interior of the vehicle by the instrument panel and console.
Alternatively, the supporting component 42 can be embodied as a
rear wheel well, and the acoustic insulator 40 can be disposed
adjacent to the interior surface of the rear wheel well such that
the acoustic insulator 40 is hidden from view by trunk compartment
side walls or rear quarter panel trim. However, it will be
appreciated that this invention may be used in any desired
environment for the purposes described below.
[0020] The structure of the acoustic insulator 40 is illustrated in
detail in FIG. 4. As shown therein, the acoustic insulator 40
includes a first layer 44 having an outer surface 46 and an inner
surface 48. The first layer 44 may be formed from any desired
material. In the illustrated embodiment, the first layer 44 is
formed from a fiber material. For example, the first layer 44 may
be formed from natural and/or synthetic fibers, such as cotton,
hemp, wool, silk, jute, ramie, sisal, polyester, polypropylene,
nylon, glass, polyethylene, or any combination thereof. It will
also be appreciated that the fiber material may include additional
materials and/or binding agents, although such is not required. In
a preferred embodiment, the first layer 44 is a needled non-woven
fiber pad. However, it will be appreciated that the fibers of the
first layer 44 may be arranged or oriented in any suitable
arrangement, including randomly oriented fibers. In a further
preferred embodiment, the first layer 44 is formed of a combination
of polyethylene and polyethylene terephthalate fibers. In a
preferred embodiment, the first layer 44 has a thickness in the
range of from about three millimeters to about ten millimeters in
thickness and a surface density in the range of from about three
hundred to about eleven hundred grams per square meter. However,
the first layer 44 may be formed having any desired thickness or
density.
[0021] The acoustic insulator 40 also includes a second layer 50
having an outer surface 52 and an inner surface 54. As best shown
in FIG. 4, the outer surface 52 of the second layer 50 is disposed
adjacent to and engages the inner surface 48 of the first layer 44.
The second layer 50 may be formed from any desired material.
Preferably, the second layer 50 is formed from a material that
functions as a barrier layer that does not allow the flow of air
therethrough. For example, the second layer 50 may be formed from a
polymer material, such as polyethylene. In a preferred embodiment,
the second layer 50 has a surface density in the range of from
about two hundred and fifty to about six hundred grams per square
meter. However, the second layer 50 may be formed having any
desired thickness or density.
[0022] The acoustic insulator 40 includes at least one protrusion
56 that extends into engagement with a surface of the supporting
component 42. In the illustrated embodiment, the acoustic insulator
40 has a plurality of such protrusions 56 provided therein, and
each of such protrusions 56 extends into engagement with the
surface of the supporting component 42, as shown in FIG. 3.
Preferably, the protrusions 56 are spaced evenly apart from one
another throughout the extent of the acoustic insulator 40,
although such is not required. Each of the illustrated protrusions
56 includes a contact surface 60 that is defined by that portion of
the inner surface 54 of the second layer 50 that engages the
vehicle panel 42. The remaining portions of the inner surface 54 of
the second layer 50 are spaced apart from the vehicle panel 42. As
a result, at least one recessed area 58 is defined between the
inner surface 54 of the second layer 50 and the adjacent surface of
the supporting component 42. Therefore, the protrusions 56 support
the acoustic insulator 40 on the supporting component 42 such that
the areas of the contact portions 60 that engage the surface of the
supporting component 42 are relatively small in comparison to the
overall area of the acoustic insulator 40 and the supporting
component 42. Thus, the protrusions 56 cause most of the acoustic
insulator 40 to be spaced apart from the supporting component 42,
while minimizing the areas of the contact portions 60 of the
acoustic insulator 40 that engage the supporting component 42. It
will be appreciated that the shapes of one or more of the
protrusions 56 can be varied to maximize the area of the at least
one recessed area 58 and to maximize the communication between the
at least one recessed area 58.
[0023] In the illustrated embodiment, each of the protrusions 56 is
formed generally in the shape of an inverted bell having a
relatively gently curved end portion that engages the surface of
the supporting component 42. Alternatively, each of the protrusions
56 may be formed generally in the shape of an inverted cone having
a relatively sharply pointed end portion that engages the surface
of the supporting component 42. However, it will be appreciated
that the protrusions 56 may be formed having any desired shape or
combination of shapes. As illustrated, the protrusions 56 may be
shaped such that the at least one recessed area 58 is a single
recessed area, although such is not required.
[0024] In a manner similar to that described for the prior art,
noise may be transmitted through the supporting component 42 or may
be generated by vibration of supporting component 42 from any other
portion of the vehicle (not shown). The sound waves from this noise
may be transmitted through the at least one recessed area 58 formed
by the protrusions 56 and may be attenuated through the first layer
44 and the second layer 50 within the at least one recessed area
58. As the insulator may be used in a partial or fully enclosed
location within the vehicle, the sound transmitted through the
insulator may be reflected from the enclosing surfaces back to
insulator 40 where it may be absorbed. The at least one recessed
area 58 also may reduce such vibration from transferring to the
first layer 44 and the second layer 50, such that the acoustic
insulation panel 40 does not amplify such vibration. It will be
appreciated that it may be desirable to minimize the areas of the
contact portions 60 to further reduce such vibration from transfer
or amplification by the acoustic insulator 40.
[0025] If desired, the size, shape, and quantity of the protrusions
56 may be selected so as to cancel specific frequencies of noises
and vibrations that are generated by the supporting component 42.
For example, the supporting component 42 may be an instrument panel
or dashboard, and the protrusions 56 may be shaped to have varying
features in various portions of the acoustic insulator 40 such that
the noises and vibrations generated by the supporting component 42
are reduced by the acoustic insulator 40 when the vehicle is
operated.
[0026] Referring now to FIG. 5, there is illustrated an apparatus,
indicated generally at 100, for manufacturing the acoustic
insulation panel illustrated in FIGS. 3 and 4 in accordance with
the method of this invention. In the illustrated apparatus 100, the
fiber layer 44 is initially fed from a spool 110 onto a conveyor
belt 112. The fiber layer 44 may be fed in a continuous strip as
illustrated or, alternatively, may be fed in the form of a series
of discrete blanks. The film layer 50 is, in the illustrated
embodiment, extruded from a press 114 onto the fiber layer 44.
Alternatively, the film layer 50 may be applied onto the fiber
layer 44 by a knife-over-roller, a curtain, a spray, or by any
other conventional means. When using these alternative applicators,
it is desirable (but not required) that the polymer be applied at a
rate that is sufficient to maintain a small layer of polymer on the
rollers, knife, or curtain to evenly coat the fiber layer 44.
[0027] The combined fiber layer 44 and film layer 50 then pass
through a cutter 116, where it is cut to a desired length. The cut
fiber layer 44 and film layer 50 are then conveyed to an oven 118.
The oven 118 is preferably heated to a temperature sufficient to
melt the film layer 50. It will further be appreciated that the
oven 118 may be heated to a temperature sufficient to cure a liquid
adhesive (not shown) of the fiber layer 44 and bind it to the
sizing on the fibers of the fiber layer 44, although such is not
required.
[0028] The combined fiber layer 44 and film layer 50 are then
conveyed to a mold 120. The mold 120 is conventional in the art and
is provided with an internal configuration that is designed to
re-shape the combined fiber layer 44 and film layer 50 so as to
form the protrusions 56 therein. This can be accomplished by
causing the mold 120 to compress the combined fiber layer 44 and
film layer 50 to conform to the internal configuration of the mold
120. It will be appreciated that the combined fiber layer 44 and
film layer 50 may also be molded to provide a desired contour,
either planar or non-planar as described above. For example, the
combined fiber layer 44 and film layer 50 may be molded to have a
curved shape corresponding to a curved supporting component, such
as a rear wheel well. The combined fiber layer 44 and film layer 50
may be molded to a desired contour and may be molded to include the
protrusion or protrusions 56 in a single molding operation,
although such is not required. The molded combined fiber layer 44
and film layer 50 may then be cut as desired, for example, to form
a completed acoustic insulator 40 by final trimming operations
indicated at 122 to remove excess material, cut outs for
pass-throughs, clips, etc., the structure of which is also known in
the art.
[0029] In accordance with the provisions of the patent statutes,
the principle and mode of operation of this invention have been
explained and illustrated in its preferred embodiment. However, it
must be understood that this invention may be practiced otherwise
than as specifically explained and illustrated without departing
from its spirit or scope.
* * * * *