This invention relates to devices used to attenuate sound emanating from mechanical or electro-mechanical operating systems where noise, sound or vibration are a consideration for the operation of such systems.
An ongoing problem associated with mechanical and electro-mechanical operating systems is the level of noise such systems generate. With the continuous technical advances in the fields of metallurgy, electrical and mechanical engineering, manufacturers of equipment are able to minimize the physical dimensions of equipment including the thickness and mass of equipment components. Sound and improved efficiency/performance often cause conflicting results. These changes often result in increased noise pollution levels. Examples of such operating systems include, but are not limited to, HVAC units, pool pumps, gas manifolds, emergency storm generators and sump pumps.
Equipment manufacturers often are limited to installing sound blankets or lining the operating system with fiber wool to reduce the noise level emanating from the operating system. Similar principles have been adopted by the gas turbine and automotive industry using combinations of fiber, acoustic foams and composite metal combinations to address the various sound issues. Although sound cancellation schemes have been proposed, no solution has been found to satisfactorily address the broad-spectrum noise cancellation signature of a mechanical or electro-mechanical operating system. The sound blankets placed over gas valves, motors, compressor and various operating systems and provide minimal sound reduction.
Such attempts to meet consumer needs have encountered manufacturing and performance issues, produced minimum reliability performance and in some cases health hazards. As an example, fiber glass/wool materials can be a nesting area for rodents. These materials also retain moisture, which causes fungal/bacteria growth. The sound blankets typically have a vinyl jacket filled with a fiberglass material commonly known as R-19. In addition, the blanket contacts the operating system, which can reduce the overall performance and life of the operating system. The blanket acts as an insulating jacket that generates heat. Elevated temperatures with respect to a normal operating temperature places stress on components causing system failures.
Sound abatement enclosures are available for sound abatement of larger industrial operating systems. However, these enclosures are typically custom-designed for a specific application of an operating system. As such these enclosures can be extremely expensive and/or cost prohibitive. Accordingly, there remains significant room for improvement in low cost noise abatement for electrical and mechanical systems especially where the system is exposed to the outdoor environment.
The present invention for a sound attenuation enclosure comprises a plurality of panels that are supported and arranged with respect to one another to form an enclosure. At least two of the panels are supported side by side and in spaced relation to one another and one or more of these two panels have an inner chamber filled with sound retardant material. In one embodiment the least two panels are supported side by side such that the panels overlap one another.
In another embodiment each of the plurality of panels has an inner enclosed chamber filled with a sound retardant material. The panels are supported side by side so that each panel is positioned in spaced relation to an adjacent panel, and the plurality of panels are arranged to form an enclosure. In addition, the panels are arranged so that a top section or bottom section of each panel overlaps a top section or bottom section of an adjacent panel. The overlapping of the panels provides an additional barrier to emanating sound pressure waves, as opposed when panels are aligned side by side but are not overlapping. A surface of the panels that form an inner surface of the enclosure may comprise a series of adjacent cavities and protrusions, which cause viscous losses as sound pressure waves move in and out of the cavities. In addition, or alternatively the inner surface of the enclosure may be lined with sound attenuating materials that form a textured service to have the same effect as the series of cavities on sound pressure waves.
The enclosure, and components of the enclosure, is transportable in the sense that all the components can be transported to a desired site and assembled to form the enclosure. Accordingly, the enclosure includes a means, associated with the first end and the second end of each panel, for supporting the plurality of panels wherein each of the panels is positioned beside another panel forming an enclosure wherein the panels are detachable from the enclosure so the enclosure can be transported. One embodiment includes a plurality of support columns that support the panels. Each of the columns includes one or more recesses within which a first end or second end of each panel is placed in mating relationship. In one embodiment, the columns are vertically disposed and the recess is an elongated, vertically disposed channel. The panels are horizontally disposed and a first end and second end of each panel is positioned in mating relationship with a recess in a column thereby supporting the panels and forming the enclosure. The panels and columns can be easily detached from one another making the enclosure and its components transportable.
A more particular description of the invention briefly described above will be rendered by reference to specific embodiments thereof that are illustrated in the appended drawings. Understanding that these drawings depict only typical embodiments of the invention and are not therefore to be considered to be limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings.
A first embodiment of the present invention for a sound attenuation enclosure is illustrated in
Various sound retardant materials are acceptable, including, but not limited to, rubber, polymer foam, water, gravel, sand, or other dense materials used for sound attenuation. In some instances, the panels 12 and/or columns 11 may not contain the sound retardant material, and the components remain hollow. Alternatively, the panels 12 may be fabricated as a solid piece of sound retardant material, and not have a chamber 22.
The panels 12 and columns 11, and those similar components described in all embodiments discussed herein, are preferably fabricated from extrusion of known materials including aluminum, steel, rubber (neoprene, polyisoprene, natural rubber, polyurethane, viton, nitrile, silicon etc.) or a plastic material (polyvinylchloride, polyethylene, polystyrene, nylon etc.). However, other methods such as blow molding, slip casting, pressing and injection molding and materials used with such methods may be used to practice the disclosed invention.
In addition, all components described in each of the embodiments may be designed so that the enclosure, including its components, is transportable to and assembled at a desired site. If necessary, the enclosure can be disassembled, and the components moved to another site or stored. The enclosure 10 and its components may range in dimensions depending on the nature of the device to be covered. The enclosure 10 can be used to cover household devices such as pool pumps, air condition units, portable generators or any other items that generates sound at an unacceptable noise level. In addition, the enclosure 10 may have commercial applications are where a temporary sound barriers is required to lessen noise impact on the surrounding area, for example military field generators and transformers or building construction/improvement sites.
The dimensions of each of the embodiments described herein will vary in part according to the size of the operating system enclosed and the desired level of noise abatement to be achieved. For example, for a typical household HVAC unit, the interior surface of the enclosure 10 would be spaced from a surface of the HVAC about two inches to about four inches; however, the distance the enclosure may be greater or less depending in part on the size of the HVAC unit. In addition, the chamber 22 may vary in size according to the materials used to fabricate the components of the enclosure, the type of filler and the sound level generated by the HVAC unit. For example, the chamber may be about 7 mm to 9 mm thick, and wall thickness of the panel 12 may be about 3 mm to about 4 mm thick. If the panels 12 are fabricated as a solid mass loaded rubber or aerated cement/rubber mix the wall thickness may be about 10 mm to about 12 mm thick. The applications relating to larger operating devices, and/or devices that create a higher level of sound of 80 decibels or higher, the wall thickness may be about 2.5″ to about 4″.
Typical household HVAC units produce noise/sound at levels typically ranging from about 74 decibels to about 78 decibels. The enclosure 10 disclosed herein, at least with respect to use with HVAC units, may reduce the noise level emanating from an enclosed operating system by 15 decibels or to around 60 decibels.
The ends of panels 12 are closed in order to retain the sound retardant material 19 within the chamber 22. For example, if the panels 12 are formed from extrusion of a moldable material, one or both ends may be open after extrusion. An end cap (not shown) can be welded on one end of the panel 12 so that the sound retardant material can be placed in the chamber 12 from an open end, which is closed by welding another end cap on the panel 22. In an injection molding process an aperture may be formed on the panel 12, preferably on one end of the panel 12, and the sound retardant material 19 may be poured into the chamber 22 and a plug (not shown) is inserted in the aperture to encase the sound retardant material 19, within the chamber 22.
With respect to the first embodiment, each of the panels 12 is supported on the columns 11 in such a manner that each panel 12 is positioned in spaced relation to an adjacent consecutive panel 12 forming a gap 104 between the panels 12. In this manner, the enclosure 10 is ventilated for dissipation of heat generated by an enclosed mechanical or electro-mechanical operating system.
With respect to
The surface of the panels 12 facing an interior of the enclosure 10 may be textured to further enhance the sound retarding effects of the enclosure 10. For example, as shown in
With respect to
Accordingly, in practice the columns 11 and panels 12 are transported to a desired location. The columns 11 are positioned around the device to be enclosed. The ends 12A and 12B of a panel 12 are inserted into the channel 14 preferably by sliding the panel 12 from the top of the column to the bottom of the column 11. Another panel 12 is then placed in position above or beside the first panel with the spacer 28 disposed there between so the panels 12 are spaced apart. This is repeated until the enclosure 10 is formed.
The base 13 is not required to form the enclosure 10. That is, the columns 11 may be free standing without the aid of the base 13. In addition, the method or means for securing the panels 12 to the columns 11 is not limited to the elongated channel 24, but may include other securing means. For example, the columns may have holes spaced vertically spaced on the column for receiving the ends of the panels 12. Alternatively, fastening mechanism as nails, bolts, clamps etc. may be used to secure the panels 12 to columns 11.
In addition, a cover 14 may be provided to further attenuate sound and protect an enclosed system from the environment. The cover 14 may take the solid configuration shown in
As shown in
A grommet 103 is then inserted in the aperture 105 between pipe 105 and panel 12 sealing the interface between the pipe 102 and the enclosure 10. In addition, or alternatively, a grommet assembly 91 described below, and shown in
A second embodiment of the enclosure 10 illustrated in
The panels 32 shown in
With respect to
The base 33 is not required to form the enclosure 30. That is, the columns 31 may be free standing without the aid of the base 33. In addition, the method or means for securing the panels 32 to the columns 31 is not limited to the elongated channel 24, but may include other securing means. For example, the columns may have holes spaced vertically and laterally on the column for receiving the ends of the panels 32. Alternatively, fastening mechanism as nails, bolts, clamps etc. may be used to secure the panels 32 to columns 31.
The enclosure 10 of the second embodiment may also include one or more apertures (not shown) similar to the above-described first embodiment to allow parts to protrude out of the enclosure 10.
A third embodiment of the enclosure is illustrated in
As shown in
With respect to
The enclosure 10 of the third embodiment may also include one or more apertures (not shown) similar to the above-described first embodiment to allow parts to protrude out of the enclosure 10.
In an embodiment shown in
In practice of each of the above-described embodiments, the components of the enclosure including the panels 64 and columns 69, if the enclosure includes columns 69, is transported to the site of the operating system. The grommet 62 is attached to the pipe 63 preferably before the installation of panels 64. The grommet 62 may be fabricated from a rubber material having a slit 68 and is flexible enough to open the grommet 62 sufficiently to receive the pipe 63. The first member 65 is preferably positioned underneath the pipe 63, then the panels 64 are installed forming gap 67 through which the pipe 63 extends. The second member 66 is then installed on top of the grommet 62 and pipe 63 as shown in
While the preferred embodiments of the present invention have been shown and described herein, it will be obvious that such embodiments are provided by way of example only. Numerous variations, changes and substitutions will occur to those of skill in the art without departing from the invention herein. Accordingly, it is intended that the invention be limited only by the spirit and scope of the appended claims.