A frusto-conical filter includes at least one layer of a filtering material, wherein one or more layers of the at least one layer of a filtering material comprises a plurality of pleats. Each of the pleats has a center axis which essentially maintains a constant distance from the center axis of its adjoining pleats. The media filter has a first end and a second end, the second end being spaced apart from the first end, and one of the first and second ends is larger than the other of the first and second ends. A method of making this media involves cutting out a frusto-conical section from a generically shaped media and aligning it in such a way as to maintain the constant distance of the pleats from the adjacent pleats.

A purification device for disinfecting and filtering intake air is disclosed. The purification device comprises a housing provided with a number of inlet perforations for allowing the intake air to enter the housing and a number of air outlet perforations for allowing air purified by the purification device to leave the housing. The purification device moreover comprises a fan arranged inside the housing to suck the intake air into the housing and blow the purified air out of the housing. The purification device further comprises an ultraviolet radiation lamp arranged inside the housing to irradiate the intake air. The purification device also comprises a high-efficiency particulate air (HEPA) filter arranged to filter the intake air before the intake air leaves the housing as purified air. The filter comprises a plurality of pleats arranged in such a manner that the angle between adjacent pleats is 30 degrees or less.

A device for treating fluid, in particular a filter device, has first and second tubular elements (12), (14) forming an element assembly (10). One element (14) is accommodated in the other element (12) forming a flow chamber (33) between the two elements (12, 14), with a first element (12) arranged in the direction of the inflow side (29) of a fluid to be treated and a second element (14) arranged in the direction of the outflow side (31) of the treated fluid in the element assembly (10). During the fluid treatment, the flow is routed through both elements (12, 14) in succession from the direction of the inflow side (29) towards the outflow side (31). In a joint viewing direction (P), the first element (12) facing the inflow side (29) at least partially has a uniform or non-uniform contour and the second element (14) facing the outflow side (31) at least partially has a non-uniform or uniform contour.

A pleated filter preparation system is provided for accurately counting pleats along a continuous sheet of pleated filter material and cutting the sheet into filter strips to be formed into filters. The pleated filter preparation system includes a pleat driver having multiple drive gears that engage with the pleats of the pleated filter material to move the pleated filter material through the system. A pleat counter counts peaks and valleys of each pleat comprising the pleated filter material so as to identify a target pleat to be cut. The pleat counter clamps and stretches the target pleat to distinguish the target pleat among the other pleats. A punch cut station cuts the target pleat to form a filter strip having a desired number of pleats. A pleat compressor compresses the filter strips to a predetermined size and then ejects the filter strips into a suitable container or bin.

A nano silver active filter element comprises a filter element body which comprises sheet filter papers stacked of layered composite structures, the sheet filter papers successively comprises a nano silver antibacterial layer, a filter layer and a protection layer from an air inlet surface to an air outlet surface; the nano silver antimicrobial layer is prepared from phenolic complex fibers loaded with nano silver particles.

Provided is a filter assembly including: a first filter medium (110) that is bent so that high-point portions (111) and low-point portions (113) defined based on a vertical plane with respect to a first direction are alternately and repeatedly formed in a second direction perpendicular to the first direction; a first filter frame (130) configured to accommodate the first filter medium (110) and to fix an edge side of the first filter medium (110); a second filter medium (120) that is bent so that the low-point portions (121) and the high-point portions (123) defined based on the vertical plane with respect to the first direction are alternately and repeatedly formed in the second direction; and a second filter frame (140) configured to accommodate the second filter medium (120) and to fix an edge side of the second filter medium (120), wherein at least a portion of the high-point portions repeatedly formed in the first filter medium (110) have different heights from those of the other high-point portions, and at least a portion of the low-point portions repeatedly formed in the second filter medium (120) have different heights from those of the other low-point portions, and the first and second filter media (110, 120) are bent in such a way that a first filter medium high-point envelope (111a) connecting high points of the first filter medium (110) and a second filter medium low-point envelope (121a) connecting low points of the second filter medium (120) correspond to each other when viewed from a cross-section including the first direction and the second direction, and the first and second filter frames (130, 140) are combined with each other so that the first filter medium high-point envelope (111a) and the second filter medium low-point envelope (121a) face each other.

A pleated filter preparation system is provided for accurately counting pleats along a continuous sheet of pleated filter material and cutting the sheet into filter strips to be formed into filters. The pleated filter preparation system includes a pleat driver having multiple drive gears that engage with the pleats of the pleated filter material to move the pleated filter material through the system. A pleat counter counts peaks and valleys of each pleat comprising the pleated filter material so as to identify a target pleat to be cut. The pleat counter clamps and stretches the target pleat to distinguish the target pleat among the other pleats. A punch cut station cuts the target pleat to form a filter strip having a desired number of pleats. A pleat compressor compresses the filter strips to a predetermined size and then ejects the filter strips into a suitable container or bin.

A scaling tool for replicating filtration characteristics of a large-scale filtration device, the scaling tool comprising a housing having a fluid inlet and a fluid outlet, and a filter receiving region in fluid communication with the fluid inlet and the fluid outlet and configured to contain a membrane comprising one or more pleats, the filter receiving region being defined by a rigid wall framework configured to hold the one or more pleats of the membrane and compress the pleats in an amount effective to replicate the filtration performance of the large-scale filtration device. Also disclosed is a methodology for configuring a filter receiving region in a scaling tool.

A cassette filter for cleaning a fluid includes: a frame; and a plurality of filter elements having a filter medium provided with a folding. The plurality of filter elements are accommodated in a frame such that at least two adjoining filter elements of the plurality of filter elements are arranged at an acute angle to one another and form a V-shaped arrangement. Each of the plurality of filter elements has folded edges which are formed by fold peaks and fold valleys and extend perpendicularly to legs of the acute angle. Each filter element of the plurality of filter elements is provided with foldings such that a height of the respective filter element is smaller at all edge regions than a height in a central region of the respective filter element, and smaller folding surfaces than the central region result at the edge regions.

Articles and methods relating to filter media are generally provided. In some embodiments, a filter media has an irregular surface structure. For instance, the filter media may comprise a plurality of peaks that are irregular in one or more ways. A ratio of a peak height standard deviation to an average peak height may be greater than or equal to 0.05, and/or a ratio of a peak spacing standard deviation to an average peak spacing may be greater than or equal to 0.08. In some embodiments, a filter media comprises a non-woven fiber web having a layer thickness of greater than 0.3 mm and/or a stiffness of less than or equal to 100 mg.