Abstract: A composite media alternative to high pressure drop glass microfiber HEPA media for use in applications where HEPA efficiency with an oily aerosol challenge with low resistance are required. The composite media contains two light filtration layers, one or both of which is charged, and the efficiency of the material can be greatly increased over a single layer containing the same weight of material. The composite media contains a backer layer to provide mechanical support to the filtration layers.

Abstract: A filter for removing gaseous components from a gas stream. The filter includes a frame with outer members and support members mounted thereto. The filter includes a prefilter layer disposed upstream in the frame and a reactive layer disposed in the frame downstream from the prefilter layer. The reactive layer includes particulate that removes gaseous components from the gas stream. A containment layer is disposed in the frame downstream from the reactive layer. The frame supports the layers from the airstream flowing through the filter. This configuration reduces the quantity of reactive material required and permits significant variability in the reactive materials used on the reactive layers because the different reactive layers have little to no effect on one another.

Abstract: A collapsible HVAC filter that includes pleated filtration media having side members mounted on opposite sides of the filtration media. The filtration media collapses to reduce filter volume. Supports maintain spacing between the side members when the filtration media is expanded. The supports may extend into openings on the upstream and downstream sides of each of the side members. The collapsed filter occupies little space relative to the expanded filter, and can be expanded to form a completed filter with little effort required by the end user.

Abstract: A filter contains fluent particulate, such as carbon granules. The filter is divided into a plurality of cell chambers by walls, including an upper wall. The upper wall has a surface that faces, and is closest to, the top surface of the particles. The upper wall surface is oriented so that, as the particles settle, any gap formed between the top surface of the particles and a portion of the upper wall surface will not extend from the upstream to the downstream sides of the filter. Instead, contact is maintained between the top surface of the particles and the upper wall surface during fluid flow through the filter, and therefore any gas flowing through the frame must flow through, and through spaces around, particles. An angle between the upper wall surface and the flow direction of gas striking the filter is greater than about three degrees.

Abstract: A collapsible HVAC filter that includes pleated filtration media having side members mounted on opposite sides of the filtration media. The filtration media collapses to reduce filter volume. Supports maintain spacing between the side members when the filtration media is expanded. The supports may extend into openings on the upstream and downstream sides of each of the side members. The collapsed filter occupies little space relative to the expanded filter, and can be expanded to form a completed filter with little effort required by the end user.

Abstract: A filter contains fluent particulate, such as carbon granules. The filter is divided into a plurality of cell chambers by walls, including an upper wall. The upper wall has a surface that faces, and is closest to, the top surface of the particles. The upper wall surface is oriented so that, as the particles settle, any gap formed between the top surface of the particles and a portion of the upper wall surface will not extend from the upstream to the downstream sides of the filter. Instead, contact is maintained between the top surface of the particles and the upper wall surface during fluid flow through the filter, and therefore any gas flowing through the frame must flow through, and through spaces around, particles. An angle between the upper wall surface and the flow direction of gas striking the filter is greater than about three degrees.

Abstract: A dual-stage vacuum cleaner filter with a pre-filtration cap having pre-filtering screens. A base with an aperture and a filter media strip pleated in the shape of a frustocone can be mounted within the dirt cup of a handheld vacuum. A circular, planar gas impermeable lid is sealingly fixed at the end of the filter media strip opposite the base. The cap is removably mounted to the base covering the filter media strip and lid. The cap has sidewall and endwall pre-filtering screens, and when the sidewall screens become loaded with debris, the endwall screen permits air to flow through a gap between the cap and the lid to the filter media strip.

Abstract: A dual-stage vacuum cleaner filter with a pre-filtration cap having pre-filtering screens. A base with an aperture and a filter media strip pleated in the shape of a frustocone can be mounted within the dirt cup of a handheld vacuum. A circular, planar gas impermeable lid is sealingly fixed at the end of the filter media strip opposite the base. The cap is removably mounted to the base covering the filter media strip and lid. The cap has sidewall and endwall pre-filtering screens, and when the sidewall screens become loaded with debris, the endwall screen permits air to flow through a gap between the cap and the lid to the filter media strip.