Patent Application
20060246799
The present invention relates generally to vehicles and, more particularly, to trim components utilized within vehicles.
It is generally considered desirable to reduce the level of noise within a vehicle passenger compartment. External noises, such as road noise, engine noise, vibrations, etc., as well as noises emanating from within passenger compartments, may be attenuated through the use of various acoustical materials. Accordingly, sound attenuating materials for vehicles, such as automobiles, are conventionally used in the dashboard, in conjunction with carpeting for floor panels, in the wheel wells, in the trunk compartment, under the hood, and as part of the headliner.
The attenuation of external noise is conventionally referred to as sound transmission loss (STL). The attenuation of internal noise is conventionally referred to as sound absorption. The acoustic impedance of a material is defined as material density times acoustic velocity, and is expressed in units of Rayls (Newton-seconds/meter3). Acoustic impedance defines how easy it is for air to move through a material. Thus, for fibrous materials, acoustic impedance depends upon the density of the fibrous material and fiber diameter. Generally, the heavier the blanket and the finer the fibers, the higher the acoustic impedance. Moreover, thicker layers typically have more acoustic impedance than thin layers. The ability of a material to attenuate noise is conventionally defined by the material's STL, acoustic impedance, and absorption characteristics.
Carpeting used to cover the floor areas of vehicles, such as automobiles, is conventionally molded into a non-planar three dimensional contoured configuration which conforms to the contours of the vehicle floor so as to fit properly. In order to make the carpeting moldable and shape-sustaining, it is conventionally provided with a backing of thermoplastic polymer composition. The thermoplastic polymer backing also serves as a barrier to improve the sound deadening properties of the carpet assembly.
Dash insulators are often mounted to a vehicle firewall which separates the passenger compartment from an engine compartment. Dash insulators are designed to reduce the transmission of noise and heat from the engine compartment into the passenger compartment. Conventional dash insulators consist of an acoustical absorber such as an open-cell polyurethane foam or a resinated fiber pad which faces the fire wall, and a barrier sheet such as a heavily filled thermoplastic material. Dash insulator barriers are conventionally produced in a compounding process followed by an extrusion or calendaring process or by an injection molding process to achieve a barrier sheet of desired thickness and width.
Conventional carpet systems and dash insulators typically include an ethylene-vinylacetate (EVA), polyethylene (PE), or polyvinylchloride (PVC) layer which serves as a barrier sheet. Unfortunately, there are several drawbacks associated with the use of EVA, PE, and PVC layers in these vehicle applications. For example, EVA, PE, and PVC are non-porous materials which can be relatively heavy when applied to carpeting, dash insulators, and other interior trim components. In addition, EVA, PE, and PVC are conventionally applied in layers have a non-varying thickness. As such, some material may be wasted in areas where sound transmission is not problematic, thereby increasing weight unnecessarily.
Various sound attenuating materials have been developed for use in reducing noise levels within passenger compartments of vehicles. For example, U.S. Pat. No. 4,851,283 to Holtrop et al., proposes a thermoformable laminate for use in headliners. The headliner comprises a non-woven fabric bonded to a foamed polymer sheet. The fabric is formed from a blend of low melting staple fibers and high melting staple fibers.
U.S. Pat. No. 5,298,694 to Thompson proposes a non-woven acoustical insulation web. The web comprises thermoplastic fibers, and particularly a blend of melt-blown microfibers and crimped bulking fibers.
U.S. Pat. No. 5,677,027 to Masuda et al., proposes a sound insulating structure comprising a covering layer, a panel, and a cushioning layer. The cushioning layer comprises a first fiber such as polyethylene terephthalate (PET) and a second fiber that is of a shell-core construction wherein the majority of the core is PET.
U.S. Pat. No. 5,817,408 to Orimo et al., proposes a sound insulating structure which includes low and high density thermoplastic fibers. PET is preferred as a thermoplastic synthetic fiber.
U.S. Pat. No. 4,529,639 to Peoples, Jr. et al. proposes a molded foam-backed carpet assembly which includes a carpet layer, a moldable thermoplastic polymer layer and one or more foam pads fusibly bonded to the thermoplastic layer and extending over less than the entire surface of the thermoplastic polymer layer to provide desired cushioning and sound and thermal insulation only in preselected areas of the carpet.
In general, the ability of conventional materials to attenuate sound increases as the amount of material increases. Unfortunately, increased materials often increases the weight of sound attenuating material, which may be undesirable. Accordingly, there is a continuing need for acoustical insulation materials for use within vehicles that exhibit superior sound attenuating properties, while also being lightweight and low in cost.
In view of the above discussion, sound attenuating and/or absorption laminates for use within vehicles such as floor coverings and other interior trim components, and methods of producing same, are provided. According to embodiments of the present invention, a sound attenuating laminate configured to be attached to an article, such as a vehicle panel, includes a substrate having a shape of the article, and polyurethane attached to selected portions of the substrate. The polyurethane is non-porous and serves as a barrier to attenuate sound passing through the substrate. Additional non-porous polyurethane may be added to one or more selected portions of the polyurethane layer to enhance sound attenuation characteristics in the one or more selected portions. According to embodiments of the present invention, one or more of the substrate surfaces may have recessed portions formed therein, and additional non-porous polyurethane may be applied in the one or more recessed portions to further enhance sound attenuation characteristics. According to embodiments of the present invention, one or more secondary articles (e.g., plastic pass-throughs, etc.) may be molded-in with the substrate and additional non-porous polyurethane may be applied over the one or more molded-in articles to further enhance sound attenuation characteristics.
According to embodiments of the present invention, a sound absorption laminate configured to be attached to an article, such as a vehicle panel, includes a substrate having a shape of the article, and breathable polyurethane attached to selected portions of the substrate. The polyurethane serves as an absorber of sound (e.g., sound generated within a vehicle compartment). Additional breathable polyurethane may be added to one or more selected portions of the polyurethane layer to enhance sound absorption characteristics in the one or more selected portions. According to embodiments of the present invention, one or more of the substrate surfaces may have recessed portions formed therein, and additional breathable polyurethane may be applied in the one or more recessed portions to further enhance sound absorption characteristics.
According to embodiments of the present invention, a porous, breathable carpet assembly (or dash insulator) for use in vehicles, is provided and includes a substrate and a porous carpet layer secured to the substrate. The substrate has opposite first and second surfaces and the porous carpet layer is adhesively secured to the substrate via a breathable polyurethane layer. The substrate first surface is configured to be attached to a vehicle panel in contacting face-to-face relationship therewith. The substrate may be formed into the shape of a vehicle floor panel (or vehicle firewall) such that the substrate first surface attaches to the vehicle floor panel (or firewall) in contacting face-to-face relationship therewith.
Breathable polyurethane may be applied onto the substrate second surface in one or more areas to enhance sound absorption characteristics of the carpet assembly. Alternatively, or in addition to, non-porous polyurethane may be applied onto the substrate second surface in one or more areas to enhance sound attenuation characteristics of the carpet assembly (or dash insulator).
Sound attenuating and/or absorption laminates, sound absorbing carpet assemblies, and sound absorbing dash insulators, according to embodiments of the present invention, can provide desired sound deadening and absorption properties in selected vehicle locations, such as floor pans, door panels, firewalls, headliners, spare tire covers, etc. Moreover, sound attenuating and/or absorption laminates according to embodiments of the present invention may have reduced overall weight without sacrificing soundproofing properties.
The accompanying drawings, which form a part of the specification, illustrate key embodiments of the present invention. The drawings and description together serve to fully explain the invention.
The present invention now is described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.
In the drawings, the thickness of lines, layers and regions may be exaggerated for clarity. It will be understood that when an element such as a layer, region, substrate, or panel is referred to as being “on” another element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being “directly on” another element, there are no intervening elements present. It will be understood that when an element is referred to as being “connected” or “attached” to another element, it can be directly connected or attached to the other element or intervening elements may also be present. In contrast, when an element is referred to as being “directly connected” or “directly attached” to another element, there are no intervening elements present. The terms “upwardly”, “downwardly”, “vertical”, “horizontal” and the like when used herein are for the purpose of explanation only.
Embodiments of the present invention provide sound attenuating and/or absorbing laminates and carpet assemblies for use in various applications, particularly automotive applications. Exemplary automotive applications within which sound attenuating and/or absorbing laminates and carpet assemblies according to embodiments of the present invention may be utilized include, but are not limited to, floor coverings, door panels, dash insulators, trunk liners headliners, various interior trim components, etc.
Referring to
The polyurethane barrier layer 16 has a density of about 1.0 to 3.0 pcf and a thickness of about 15 to 30 mm. The polyurethane barrier layer 16 comprises an isocyanate, a polyol and various additives such as crosslinking agents, catalysts, blowing agents and the like, the selection of which will be within the skill of one in the art. For example, the isocyanate component of the polyurethane includes one or more compounds selected from the group-consisting of diphenylmethane-4,4′-diisocyanate, diphenyldimethylmethane-4,4′-diisocyanate, phenylene-1,4-diisocyanate, 2,2′,6,6′-tetramethyldiphenylmethane-4,4′-diisocyanate, diphenyl-4,4′diisocyanate, diphenylether-4,4′-diisocyanate or its alkyl-, alkoxy- or halogen-substituted derivatives, toluylene-2,4- and -2,6-diisocyanates or their commercially available mixture, 2,4-diisocypropylphenylene-1,3-diisocyanate, m-xylylenediisocyanate, and p-xylylenediisocyanate.
Further, in the practice of the present invention, any desired types of polyester polyols and polyether polyols may be used as a polyol component of the polyurethane prepolymer solution. Examples of the crosslinking agent usable in the present invention include trifunctional or more functional polyisocyanate or hydroxyl compounds, for example, one or more compounds selected from the group consisting of ethylene glycol, propylene glycol, butane-1,4-diol, hexane-2,5-diol, 2,2-dimethylpropane-1,3-diol, hexane-1,6-diol, 2-methylhexane-1,6-diol, 2,2-dimethylhexane-1,3-diol, p-bishydroxymethyl cyclohexane, 3-methylpentane-1,4-diol, 2,2-diethylpropane-1,3-diol and the like. As the catalyst, tertiary amines, organic tin compounds, organic lead compounds and the like may be used. As the solvent capable of dissolving polyols and isocyanates, methyl ethyl ketone, ethyl acetate, toluene, xylene, dimethylformamide, methyl isobutyl ketone, butyl acetate, acetone or the like may be used alone or in combination. The polyurethane barrier layer 16 can be in the form of a slab foam, cast foam or a thermoformable foam.
According to embodiments of the present invention, the polyurethane may include a filler, such as calcium carbonate, calcium hydroxide, aluminum trihydrate, talc, bentonite, barytes, silica, clay and mica.
An exemplary unfilled polyurethane barrier material that may be used in accordance with embodiments of the present invention is Bayer Elastomer (Bayer AG, Pittsburgh, Pa.). An exemplary filled polyurethane barrier material that may be used in accordance with embodiments of the present invention is Huntsman Rimline SH 80309 (Huntsman Corporation, Salt Lake City, Utah).
The substrate 14 may be formed from any type of material including, but not limited to foam (e.g., polyurethane foam, thermoplastic foam, etc.), massback, and other thermoformable fibrous materials including those derived from natural and synthetic fibers. Massback is a relatively dense material, normally impermeable to air and thermoformable. Massback can be formed from virtually any plastic or rubber material which contains a high-mass filler material. An exemplary massback includes ethylene-vinylacetate (EVA) copolymer, polyethylene, or polyvinyl-chloride (PVC), and a high-mass filler material, such as glass, calcium carbonate or barium sulfate, added to increase the mass. Other suitable materials for the substrate include thermoformable stiff thermoplastic materials such as polystyrene, polyphenyl sulfide and polycarbonate, fiber-reinforced thermoplastics and fiber-reinforced thermosets such as epoxies, phenolics and the like.
The substrate 14 may be formed into a three-dimensional shape of the article 12 such that the substrate first surface 14a attaches to the article 12 in contacting face-to-face relationship therewith. The substrate 14 can have form retention characteristics such that it maintains a form imposed upon it. Alternatively, the substrate 14 may have elastic memory such that it is unable to maintain an unassisted non-flat configuration. For substrate materials having elastic memory, the polyurethane barrier layer 16 also serves the function of a binder such that the substrate 14 can maintain a shape imposed upon it via molding and other operations.
The article 12 may be virtually any type of vehicle panel (e.g., floor panel, firewall, door panel, wheel well, trunk compartment panel, etc.). For example, a sound attenuating laminate 10 according to embodiments of the present invention may be utilized as a dash insulator when attached to a vehicle firewall, may be utilized as a floor covering when attached to vehicle floor panels, and may be utilized as virtually any type of vehicle interior trim component.
Vehicle panels to which sound attenuating laminates according to the present invention may be attached may have various shapes, configurations, and sizes, and may be formed of various materials including, but not limited to metals, polymers, and combinations thereof. For example, a vehicle panel may be sheet metal having a three-dimensional configuration. Alternatively, a vehicle panel may be a substantially flat piece of sheet metal.
Referring to
Referring to
Referring to
Sound attenuating laminates according to embodiments of the present invention illustrated in
Referring to
A polyurethane barrier layer 16 is applied to the substrate second surface 14b such that it overlies the molded-in secondary article 23 and surrounding area. The polyurethane barrier layer 16 is a non-porous polyurethane and is configured to attenuate sound passing through the article 12 and through the substrate 14. The additional polyurethane 16 enhances sound attenuation characteristics of the sound attenuating laminate 410 in the area of the molded-in secondary article 23. Secondary articles molded-in with substrates according to embodiments of the present invention can have various sizes, shapes, and configurations.
Referring now to
A substrate configured to be attached to the article in face-to-face contacting relationship is formed into a shape corresponding to that of the article (Block 1010). Areas of the substrate in which apertures are to be formed therethrough may be identified (Block 1020). Polyurethane is then applied (e.g., via spraying or other application techniques) to the substrate in areas identified as requiring enhanced sound attenuation characteristics (Block 1030). Areas of the substrate in which apertures are to be formed therethrough are preferably avoided during the application of the polyurethane barrier layer. Additional polyurethane may be added to areas identified as requiring additional sound attenuation characteristics (Block 1040). This may encompass applying additional polyurethane directly onto an existing polyurethane barrier layer and/or into one or more recessed portions formed within the substrate.
According to embodiments of the present invention, various ones of the operations illustrated in
Furthermore, operations represented by Blocks 1030 and 1040 may be performed substantially simultaneously. For example, additional polyurethane can be added by adjusting processing speeds and/or by adjusting dispensing pressure, as would be understood by those skilled in the art.
Referring now to
The breathable polyurethane layer 46 has a density of about 1.0 to 3.0 pcf and a thickness of about 15 to 30 mm. The breathable polyurethane layer 46 comprises an isocyanate, a polyol and various additives such as crosslinking agents, catalysts, blowing agents and the like, the selection of which will be within the skill of one in the art. For example, the isocyanate component of the polyurethane includes one or more compounds selected from the group consisting of diphenylmethane-4,4′-diisocyanate, diphenyldimethylmethane-4,4′-diisocyanate, phenylene-1,4-diisocyanate, 2,2′,6,6′-tetramethyldiphenylmethane-4,4′-diisocyanate, diphenyl-4,4′diisocyanate, diphenylether-4,4′-diisocyanate or its alkyl-, alkoxy- or halogen-substituted derivatives, toluylene-2,4- and -2,6-diisocyanates or their commercially available mixture, 2,4-diisocypropylphenylene-1,3-diisocyanate, m-xylylenediisocyanate, and p-xylylenediisocyanate.
Further, in the practice of the present invention, any desired types of polyester polyols and polyether polyols may be used as a polyol component of the polyurethane prepolymer solution. Examples of the crosslinking agent usable in the present invention include trifunctional or more functional polyisocyanate or hydroxyl compounds, for example, one or more compounds selected from the group consisting of ethylene glycol, propylene glycol, butane-1,4-diol, hexane-2,5-diol, 2,2-dimethylpropane-1,3-diol, hexane-1,6-diol, 2-methylhexane-1,6-diol, 2,2-dimethylhexane-1,3-diol, p-bishydroxymethyl cyclohexane, 3-methylpentane-1,4-diol, 2,2-diethylpropane-1,3-diol and the like. As the catalyst, tertiary amines, organic tin compounds, organic lead compounds and the like may be used. As the solvent capable of dissolving polyols and isocyanates, methyl ethyl ketone, ethyl acetate, toluene, xylene, dimethylformamide, methyl isobutyl ketone, butyl acetate, acetone or the like may be used alone or in combination. The breathable polyurethane layer 46 can be in the form of a slab foam, cast foam or a thermoformable foam.
According to embodiments of the present invention, the breathable polyurethane layer 46 may include a filler such as calcium carbonate, calcium hydroxide, aluminum trihydrate, talc, bentonite, barytes, silica, clay and mica.
An exemplary breathable polyurethane material that may be used in accordance with embodiments of the present invention is Bayer Baypreg SA (Bayer AG, Pittsburgh, Pa.).
The substrate 44 may be formed from any type of material including, but not limited to foam (e.g., polyurethane foam, thermoplastic foam, etc.), massback, and other thermoformable fibrous materials including those derived from natural and synthetic fibers. Massback is a relatively dense material, normally impermeable to air and thermoformable. Massback can be formed from virtually any plastic or rubber material which contains a high-mass filler material. An exemplary massback includes ethylene-vinylacetate (EVA) copolymer, polyethylene, or polyvinyl-chloride (PVC), and a high-mass filler material, such as glass, calcium carbonate or barium sulfate, added to increase the mass. Other suitable materials for the substrate include thermoformable stiff thermoplastic materials such as polystyrene, polyphenyl sulfide and polycarbonate, fiber-reinforced thermoplastics and fiber-reinforced thermosets such as epoxies, phenolics and the like.
The substrate 44 may be formed into the shape of the article 42 such that the substrate first surface 44a attaches to the article 42 in contacting face-to-face relationship therewith. The substrate 44 can have form retention characteristics such that it maintains a form imposed upon it. Alternatively, the substrate 44 may have elastic memory such that it is unable to maintain an unassisted non-flat configuration. For substrate materials having elastic memory, the layer of breathable polyurethane 46 also serves the function of a binder such that the substrate 44 can maintain a shape imposed upon it via molding and other operations.
As illustrated in
As illustrated in
According to embodiments of the present invention, the sound absorbing laminates of
The article 42 to which sound absorbing laminates 40, 140, 240 according to the embodiments of
Referring to
Referring now to
A substrate configured to be attached to the article in face-to-face contacting relationship is formed into a shape corresponding to that of the article. (Block 2010). Areas of the substrate in which apertures are to be formed therethrough may be identified. (Block 2020). Breathable polyurethane is then applied (e.g., via spraying or other application techniques) to the substrate in areas identified as requiring enhanced sound absorption characteristics. (Block 2030). Areas of the substrate in which apertures are to be formed therethrough are preferably avoided during the application of the polyurethane barrier layer. Additional polyurethane may be added to areas identified as requiring additional sound absorption characteristics (Block 2040). This may encompass applying additional breathable polyurethane directly onto an existing layer of breathable polyurethane and/or into one or more recessed portions formed within the substrate.
According to embodiments of the present invention, various ones of the operations illustrated in
Furthermore, operations represented by Blocks 2030 and 2040 may be performed substantially simultaneously. For example, additional polyurethane can be added by adjusting processing speeds and/or by adjusting dispensing pressure, as would be understood by those skilled in the art.
Referring now to
The substrate first surface 54a is configured to be attached to a vehicle floor panel 52 in contacting face-to-face relationship therewith. The substrate 54 may be formed from any type of material including, but not limited to foam (e.g., polyurethane foam, thermoplastic foam, etc.), massback, and other thermoformable fibrous materials including those derived from natural fibers, man-made fibers, and/or blends of natural fiber and man-made fibers.
The substrate 54 may be formed into the shape of a vehicle floor panel 52 such that the substrate first surface 54a attaches to the vehicle floor panel 52 in contacting face-to-face relationship therewith. The substrate 54 can have form retention characteristics such that it maintains a form imposed upon it. Alternatively, the substrate 54 may have elastic memory such that it is unable to maintain an unassisted non-flat configuration. For substrate materials having elastic memory, the breathable polyurethane layer 56 also serves the function of a binder such that the substrate 54 can maintain a shape imposed upon it via molding and other operations.
An exemplary porous, breathable carpet assembly 50 is illustrated in
Referring to
An exemplary porous, breathable dashboard insulator 80 is illustrated in
Referring now to
Breathable polyurethane may be applied onto the substrate second surface in one or more areas to enhance sound absorption characteristics of the carpet assembly (Block 3060). Alternatively, or in addition to, non-porous polyurethane may be applied onto the substrate second surface in one or more areas to enhance sound attenuation characteristics of the carpet assembly (Block 3070).
Sound attenuating laminates and sound absorbing laminates according to the various embodiments of the present invention facilitate acoustical “tuning” wherein acoustical “hot spots” can be identified and additional material (i.e., non-porous polyurethane to provide a barrier to sound, and/or breathable polyurethane to absorb sound) can be added to attenuate sound. Sound attenuating laminates according to embodiments of the present invention can be “tuned” to provide desired sound attenuating characteristics in selected vehicle locations, such as floor panels, firewalls, door panels, wheel wells, trunk compartment panels, etc. The term “tuned” means that portions of a sound attenuating and/or absorbing laminate can be formed to have a specific acoustic impedance designed to attenuate sound in one or more frequencies or frequency bands, and/or to have a specific absorption characteristic designed to absorb sound in one or more frequencies or frequency bands. Moreover, sound attenuating/absorption laminates according to embodiments of the present invention may have reduced overall weight compared with conventional sound proofing materials, and without sacrificing sound attenuation properties.
The foregoing is illustrative of the present invention and is not to be construed as limiting thereof. Although a few exemplary embodiments of this invention have been described, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention as defined in the claims. Therefore, it is to be understood that the foregoing is illustrative of the present invention and is not to be construed as limited to the specific embodiments disclosed, and that modifications to the disclosed embodiments, as well as other embodiments, are intended to be included within the scope of the appended claims. The invention is defined by the following claims, with equivalents of the claims to be included therein.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 09990115 | Nov 2001 | US |
| Child | 11475333 | Jun 2006 | US |
