Cleanroom Suspended Ceiling Molding Having a Gasket

The invention relates to suspended panel ceilings located in a cleanroom, specifically to a wall molding that supports the ends of the beams that abut the walls surrounding such ceilings that when installed provide a seal between the walls and the molding and the ceilings panels and the molding to maintain the environmental integrity of the cleanroom.

Cleanrooms are areas in which particle concentration and environmental conditions are controlled within specified limits. The limits of the particle concentrations are normally set by the requirements of the process occurring within the space so that contamination of people, processes and equipment can be mitigated.

A suspended ceiling system is commonly used in cleanrooms to provide access to utility lines, ductwork, and other infrastructure components above the ceiling while maintaining the environmental integrity of the engineered space below. These ceiling systems include metal beams or runners forming a grid system adapted to receive lay in ceiling tiles that are supported by the grid system. These grid systems can have a plurality of metal or plastic main beams and a plurality of metal or plastic cross members that span the gaps between the main beams to form a grid into which panels are laid.

Where a suspended ceiling meets a wall, it is customary to provide a sheet metal wall molding. This molding serves to support the edges of ceiling panels or tiles and the ends of grid runners and to conceal normal gaps between these edges and ends and the wall. Walls conventionally constructed of drywall are often not flat because of the presence of corner bead, taped joints, and other disturbances. These irregularities create gaps between the wall and the molding allowing untreated air from above the ceiling to migrate to the engineered space below, which negatively impacts the environmental integrity of the engineered space below.

Existing solutions for maintaining the seal between the wall molding and the wall to which the molding is attached have limitations. Sealants, such as caulk, are commonly used, but they are often messy, time-consuming to apply, and lack flexibility for installing, repositioning, or replacing moldings.

Accordingly, there is a need for a solution that provides a secure and reliable means of sealing the molding of a suspended ceiling panel that is easy to install and remove without affecting the environmental integrity of the engineered space. The disclosed invention is specifically designed to address the unique requirements and challenges with maintaining the environmental integrity of engineered spaces.

The invention provides a wall molding for suspended ceiling systems that is capable of conforming to ordinary deviations from a flat plane in the surface of a wall against which it is mounted. The inventive wall angle, in various embodiments, has a gasket on the wall side of a vertical leg that, in a free state, projects outward from the wall side of the molding toward the wall. When the gasket of the molding is drawn against the wall surface, the gasket contacts the surface of the wall forming an air-tight seal around the exterior of the suspended ceiling system. This seal occurs regardless of whether the wall surface bulges or recedes from a flat plane, the gasket remains extended towards the wall. Consequently, the environmental integrity of engineered spaces below the ceiling is maintained.

The wall molding includes a vertical leg connected to a horizontal leg at a substantially ninety-degree angle. The vertical leg has top end and opposite bottom end along with a polygonal shape forming an apex on one surface of the vertical leg and void or indent on the opposite surface. The apex may be a point or flat. A wall gasket adapted to create an air-tight seal between the wall molding and the wall when the wall molding is attached to the wall which projects outward from the vertical leg in a direction away from the horizontal leg. The horizontal leg has a top surface, opposite bottom surface, and terminal end opposite the end connected to the vertical leg. In certain embodiments, the vertical and horizontal legs may be formed of folded sheet metal.

In certain embodiments, the wall gasket is a sheet, semi-circular shape, finger, L-shape, or combination thereof. For example, the wall gasket may be a combination of a sheet and finger wherein the sheet portion of the wall gasket is located above the finger which projects outward from within the void. In other embodiments, the gasket may be comprised of two or more projections. For example, an L-shaped element may project outward from the top of the void whereas a finger projects outward from the bottom of the void. In addition, the wall gasket may be a compressible polymer.

In certain embodiments, the void may be located closer to the bottom end than the top end of the vertical leg.

In certain embodiments, the wall molding further includes a beam gasket projecting upward from the top surface. Such a beam gasket may also be a sheet, semi-circular shape, finger, or combination thereof. For example, the beam gasket may be a combination of a sheet and finger wherein the sheet portion of the wall gasket is located closer to the vertical leg than the finger which projects outward from the top surface in a direction away from the vertical leg. In such an embodiment, a portion of the gasket may be adapted to fold over another portion to provide added sealing functionality.

In certain embodiments, the beam gasket may be a compressible polymer.

It is to be understood that both the foregoing general description and the following detailed description are exemplary, but are not restrictive, of the invention.

The features and benefits of the disclosed molding, beams, and ceiling system are illustrated and described by reference to exemplary embodiments. The disclosure also includes the drawing, in which like reference numbers refer to like elements throughout the various figures that comprise the drawing. This description of exemplary embodiments is intended to be read in connection with the accompanying drawing, which is to be considered part of the entire written description. Accordingly, the disclosure expressly should not be limited to such exemplary embodiments illustrating some possible non-limiting combinations of features that may exist alone or in other combinations of features.

In the description of embodiments, any reference to direction or orientation is merely intended for convenience of description and is not intended in any way to limit the scope of the present invention. Relative terms such as “lower,” “upper,” “horizontal,” “vertical,” “above,” “below,” “up,” “down,” “top,” and “bottom” as well as derivatives of those terms (e.g., “horizontally,” “downwardly,” “upwardly,” etc.) should be construed to refer to the orientation as then described or as shown in the drawing under discussion. These relative terms are for convenience of description only and do not require that the apparatus be construed or operated in a particular orientation. Terms such as “attached,” “affixed,” “connected,” “coupled,” “interconnected,” and similar terms refer to a relationship wherein structures are secured or attached to one another either directly or indirectly through intervening structures, as well as both moveable or rigid attachments or relationships, unless expressly described otherwise.

The ceiling system includes at least two main beams running substantially parallel to each other. The main beams are supported by angled molding attached to at least two walls. Cross beams run between the main beams. The cross beams may connect to other cross beams, main beams, or the wall. The main beams and cross beams form a grid into which panels may be laid. The panel can be standard commercially available products and, as is conventional, are duplicated across the expanse of a grid.

The wall can be constructed of drywall sheets secured to vertical studs or other structure at the backside thereof. Where drywall sheets are joined, particularly where their ends are abutted and taped or where they intersect at an outside corner and are capped with a corner bead and joint compound, the wall will have localized bulges meaning that the wall surface deviates from a flat plane.

As outlined above, the ceiling system includes both main beams and intersecting cross beams. Regardless of type, beams are formed generally of flat sheet metal folded into an inverted T cross section having a web, a bulb at the top of the web, and a horizontal flange extending in both directions from the bottom of the web. The web is formed of two adjacent layers typically stitched together by punching a portion of one layer through a portion of the second layer surface creating an indentation in the first layer and a bump in the second layer surface. In some instances, the beams are not folded metal but instead are made of extruded material, such as metal (e.g., aluminum) or polymers.

The main beams are typically suspended from a structural ceiling by wires. The main beams, which run parallel to one another, are generally spaced 24 inches, 36 inches, or 48 inches (61 cm, 91 cm, or 122 cm) apart. A straight, finished main beam may continuously emerge from a roll-forming operation, and then be cut, on the run, into suitable lengths of, for instance, 12 feet (366 cm).

Crossbeams are connected to the main beams through slots in the main beams. Such connections form corners. In such a configuration, the cross beams are typically supported by the main beams. Cross beams are manufactured in a manner like main beams and may be cut into lengths of 2, 3, or 4 feet (61 cm, 91 cm, or 122 cm). Cross beams may also be connected to brackets by clips. When cross beams are connected to main beams, the ceiling system with a grid adapted to receive laid-in panels is formed.

Various type of lay in panels can be used with the grid system. For example, acoustic tiles may be used. In the case of acoustical tiles, the tiles may comprise fiberglass, mineral wool (such as rock wool, slag wool, or a combination thereof), synthetic polymers (such as melamine foam, polyurethane foam, or a combination thereof), mineral cotton, silicate cotton, gypsum, or combinations thereof. In some embodiments, the tile provides a sound attenuation function and preferred materials for providing the sound attenuation function include mineral wool.

Acoustic ceiling panels exhibit certain acoustical performance properties. Specifically, the American Society for Testing and Materials (ASTM) has developed test method E1414 to standardize the measurement of airborne sound attenuation between room environments 3 sharing a common plenary space. The rating derived from this measurement standard is known as the Ceiling Attenuation Class (CAC). Ceiling materials and systems having higher CAC values have a greater ability to reduce sound transmission through a plenary space—i.e. sound attenuation function. In certain embodiments, the lay in tiles incorporated into the ceiling system provide a CAC (Ceiling Attenuation Class) rating of at least 35, preferably at least 40. CAC is further described below.

Another important characteristic for acoustic ceiling panel materials is the ability to reduce the amount of reflected sound in a room. One measurement of this ability is the Noise Reduction Coefficient (NRC) rating as described in ASTM test method C423. This rating is the average of sound absorption coefficients at four ⅓ octave bands (250, 500, 1000, and 2000 Hz), where, for example, a system having an NRC of 0.90 has about 90% of the absorbing ability of an ideal absorber. A higher NRC value indicates that the material provides better sound absorption and reduced sound reflection—sound absorption function.

Acoustic ceiling panels can have different constructions. In some cases, the body may be porous, thereby allowing airflow through the body between an upper surface and a lower surface. The body may be comprised of a binder and fibers. In some embodiments, the body may further comprise a filler and/or additive.

Non-limiting examples of binder may include a starch-based polymer, polyvinyl alcohol (PVOH), a latex, polysaccharide polymers, cellulosic polymers, protein solution polymers, an acrylic polymer, polymaleic anhydride, epoxy resins, or a combination of two or more thereof.

The binder may be present in an amount ranging from about 1 wt. % to about 25 wt. % based on the total dry weight of the body—including all values and sub-ranges there-between. The phrase “dry weight” refers to the weight of a referenced component without the weight of any carrier. Thus, when calculating the weight percentages of components in the dry-state, the calculation should be based solely on the solid components (e.g., binder, filler, hydrophobic component, fibers, etc.) and should exclude any amount of residual carrier (e.g., water, VOC solvent) that may still be present from a wet-state, which will be discussed further herein. According to the present invention, the phrase “dry-state” may also be used to indicate a component that is substantially free of a carrier, as compared to the term “wet-state,” which refers to that component still containing various amounts of carrier.

Non-limiting examples of filler may include powders of calcium carbonate, including limestone, titanium dioxide, sand, barium sulfate, clay, mica, dolomite, silica, talc, perlite, polymers, gypsum, wollastonite, expanded-perlite, calcite, aluminum trihydrate, pigments, zinc oxide, or zinc sulfate. The filler may be present in an amount ranging from about 25 wt. % to about 99 wt. % based on the total dry weight of the body—including all values and sub-ranges there-between.

Non-limiting examples of additives include defoamers, wetting agents, biocides, dispersing agents, flame retardants, and the like. The additive may be present in an amount ranging from about 0.01 wt. % to about 30 wt. % based on the total dry weight of the body—including all values and sub-ranges there-between.

The fibers may be organic fibers, inorganic fibers, or a blend thereof. Non-limiting examples of inorganic fibers mineral wool (also referred to as slag wool), rock wool, stone wool, and glass fibers. Non-limiting examples of organic fiber include fiberglass, cellulosic fibers (e.g. paper fiber—such as newspaper, hemp fiber, jute fiber, flax fiber, wood fiber, or other natural fibers), polymer fibers (including polyester, polyethylene, aramid-i.e., aromatic polyamide, and/or polypropylene), protein fibers (e.g., sheep wool), and combinations thereof. Depending on the specific type of material, the fibersmay either be hydrophilic (e.g., cellulosic fibers) or hydrophobic (e.g. fiberglass, mineral wool, rock wool, stone wool). The fibers may be present in an amount ranging from about 5 wt. % to about 99 wt. % based on the total dry weight of the body—including all values and sub-ranges there-between.

A face coating may comprise a binder, a pigment, and optionally a dispersant.

Non-limiting examples of a binder include polymers selected from polyvinyl alcohol (PVOH), latex, an acrylic polymer, polymaleic anhydride, or a combination of two or more thereof. Non-limiting examples of a latex binder may include a homopolymer or copolymer formed from the following monomers: vinyl acetate (i.e., polyvinyl acetate), vinyl propinoate, vinyl butyrate, ethylene, vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride, ethyl acrylate, methyl acrylate, propyl acrylate, butyl acrylate, ethyl methacrylate, methyl methacrylate, butyl methacrylate, hydroxyethyl methacrylate, hydroxyethyl acrylate, styrene, butadiene, urethane, epoxy, melamine, and an ester. Preferably the binder is selected from the group consisting of aqueous lattices of polyvinyl acetate, polyvinyl acrylic, polyurethane, polyurethane acrylic, polystyrene acrylic, epoxy, polyethylene vinyl chloride, polyvinylidene chloride, and polyvinyl chloride.

The face coating may be a color surface coating. The term “color surface coating” refers to a surface coating comprising a color pigment and the resulting surface coating exhibits a color on the visible color spectrum—i.e., violet, blue, green, yellow, orange, or red. The color surface coating may also have a color of white, black, or grey. The color surface coating may further comprise combinations of two or more colors—such a primary color (i.e., red, yellow, blue) as well as an achromatic color (i.e., white, grey).

A non-limiting example of a color surface coating may be pink and produced from a combination of red and white pigments. Another non-limiting example of a color surface coating may be green and produced from a combination of blue and yellow pigments. Another non-limiting example of a color surface coating may be brown and produced from a combination of red, yellow, and black pigments.

The pigment may be an inorganic pigment. Non-limiting examples of inorganic pigment include particles of carbon black, graphite, graphene, copper oxide, iron oxide, zinc oxide, calcium carbonate, manganese oxide, titanium dioxide and combinations thereof. The inorganic pigments may include individual particles having colors selected from, but not limited to, red, blue, yellow, black, green, brown, violet, white, grey and combinations thereof. The particles that make up the first pigment may have a particle size ranging from about 15 nm to about 1000 μm—including all sizes and sub-ranges there-between.

Ceiling tiles other than the acoustic tiles described above can also be used in embodiments of the invention. For example, tiles made from metal, wood, plastic, composites, or other materials can be used.

A first embodiment of a wall moldingconstructed in accordance with the invention is illustrated in. The moldingis secured to the wall by fasteners such as screws, nails, or staples. It is customary that the fasteners are driven through the drywall into the underlying studs or other framework or support. Typically, the studs will be spaced horizontally a regular distance along the wall.

The wall moldingcomprises a generally vertical legconnected to a generally horizontal leg. The wall molding, preferably, is a single sheet of metal, typically steel sufficiently hard to exhibit a springiness or resilience as discussed below. The wall moldingwhile it can be brake-formed, is preferably roll-formed using conventional roll-forming techniques known in the industry.

The vertical legincludes a polygonal shapeprojecting outward from the plane of the vertical legin the direction of the horizontal leg. The polygonal shapeforms an apexon the front of the vertical legand a voidon the rear. The voidmust be large enough to allow the wall gasketto provide an airtight seal while permitting the wall moldingto remain flush against the wall.

In certain embodiments, the apexis a point which may form a voidwhich is parabolic in shape. In other embodiments, the apexdefines a flat surface which may form a voidwhich is square or rectangular in shape.

In certain embodiments, the bottom of the polygonal shapeis offset from the top of the polygonal shapesuch that the horizontal legis out of line with the plane of the vertical leg.

In certain embodiments, the polygonal shapeis closer to the horizontal legthan it is to the top of the vertical leg. In other embodiments, the polygonal shapeis closer to the top of the vertical legthan it is to the horizontal leg. In still other embodiments, the polygonal shapeis located about the same distance between the top of the vertical legand the horizontal leg.

In certain embodiments, not shown in the Figures, the gasketcomprises a sheet and a finger or L-shaped projection, wherein the sheet portion is located in the voidwith a uniform thickness.

The vertical legalso includes a wall gasketprojecting outward from the plane of the vertical legin the direction away from the horizontal leg. The wall gasketmay take on any shape. For example, the wall gasketmay be a semi-circular shape, a finger, a sheet, or a combination thereof attached to the rear of the vertical leg. Similarly, the wall gasketmay be located anywhere along the rear of the vertical leg. For example, the wall gasketmay be located above, below, or within the voidcreate by the polygonal shape. The wall gasketmay be made of any flexible material. For example, the wall gasketmay be polymer based (e.g., a thermoplastic elastomer).

In certain embodiments, the top of the vertical legmay be folded back over itself. The fold may be in the direction of the horizontal leg, like that depicted in. Conversely, the fold may be in the direction away from the horizontal leg.

The horizontal legincludes a beam gasketprojecting outward from the top of the horizontal legin the direction away from the vertical leg. The beam gasketmay take on any shape. For example, the beam gasketmay be a semi-circular shape, a finger, a sheet, or a combination thereof attached to the rear of the vertical leg. Similarly, the beam gasketmay be located anywhere along the top of the horizontal leg. For example, the beam gasketmay be located closer to the terminal edgeof the horizontal beamthan it is to the vertical beam. Conversely, the beam gasketmay be located further from the terminal edgeof the horizontal beamthan it is to the vertical beam. The beam gasketmay even be a substantially equal distance between the terminal edgeof the horizontal beamand the vertical beam. The beam gasketmay also be made of any flexible material. For example, the beam gasketmay be polymer based (e.g., a thermoplastic elastomer).

In certain embodiments, the terminal end of the horizontal beammay be folded back over itself. The fold may be in the upward direction, like that depicted in. Conversely, the fold may be in the downward direction.

The moldingmay be constructed of metal, carbon fiber, plastic, wood, or composite materials. In one embodiment, the moldingis made of steel. In other embodiments, the moldingis made out of aluminum.

Although illustrated and described above with reference to certain specific embodiments, the present invention is nevertheless not intended to be limited to the details shown. Rather, various modifications may be made in the details within the scope and range of equivalents of the claims and without departing from the spirit of the invention. It is expressly intended, for example, that all ranges broadly recited in this document include within their scope all narrower ranges which fall within the broader ranges.