A spunbond non-woven fabric includes a thermoplastic continuous filament. A CV value of air permeability of the non-woven fabric is 15% or less, bending resistance in a machine direction of the non-woven fabric is 40 mN or more and 80 mN or less, the non-woven fabric includes a projected part and a recessed part, and in a non-woven fabric cross-section, a thickness from one surface to another surface of the projected part is determined to be t.sub.A, a thickness from one surface to another surface of the recessed part is determined to be t.sub.B, and respective distances from one surface of the projected part to one surface of the recessed part are determined to be t.sub.C and t.sub.D (t.sub.C<t.sub.D), and the non-woven fabric has a relation represented by formulas (1) and (2) below:

0.5≤1−t.sub.B/t.sub.A<1.0  (1)

0.65<t.sub.C/t.sub.D<1.0  (2).

An apparatus and method are provided for an air filter configured to be mounted onto an air inlet of an internal combustion engine. The air filter comprises a first end cap configured to couple with a base which is configured to support a conventional air filter and provide an interface between the conventional air filter and the air inlet. A filter medium which is relatively thicker than the conventional air filter is configured to remove particulate matter and other contaminates from an incoming airstream. A second end cap is configured to couple with a cover which is configured to fasten the conventional air filter and the base onto the air inlet, such that the incoming airstream is directed through the filter medium. The air filter is configured to be installed in place of the conventional air filter without necessitating alteration of the base and cover.

An air filter includes: a pleated filter material folded into a zig-zag form at folding lines along a first direction to have peak parts and valley parts arising alternately in a second direction perpendicular to the first direction, trapping fine particles in a gaseous matter flowing in a gas flow direction perpendicular to the first direction and the second direction; a filter frame being a rectangular filter frame including one pair of first frame materials facing each other in the second direction having end parts in the first direction, and one pair of second frame materials facing each other in the first direction having end parts in the second direction, opening in the gas flow direction and housing the pleated filter material, each of the first frame materials and each of the second frame materials being combined to provide an overlap part.

An energy-transmissible air filtration system having at least one mechanical filter and at least one electromagnetic energy source. The electromagnetic energy source generates an electromagnetic energy wave or force that traverses the at least one mechanical filter. This results in substantially simultaneous mechanical filtration and energy-based decontamination of an airstream. Other features of the embodiments are also shown.

An energy-transmissible air filtration system having at least one mechanical filter and at least one electromagnetic energy source. The electromagnetic energy source generates an electromagnetic energy wave or force that traverses the at least one mechanical filter. This results in substantially simultaneous mechanical filtration and energy-based decontamination of an airstream. Other features of the embodiments are also shown.

The invention pertains to an air filter element comprising: a filter medium pack comprising a filter medium, said filter medium pack having an optionally substantially planar first side and an optionally substantially planar second side, said first side and second side optionally being parallel; and a guiding rim comprising a sealing surface having at least a radially oriented component, arranged on at least one of said first side and said second side, wherein a circumference of the or each guiding rim comprises at least one convex portion and at least one concave portion; and wherein a contour of said filter medium pack corresponds to said convex portion of said guiding rim and at least part of said concave portion. The invention also pertains to a method for producing an air filter element.

A filter element for an air filter of a motor vehicle includes a frame part which surrounds a filter material of the filter element. The filter element is insertable into a receiving space which is provided by a housing of the air filter. The filter element has a holding element which is movable from an initial position into a functional position by inserting the filter element in the receiving space. In the functional position, a fastening element can be fixed to the holding element. The fastening element is configured for securing a cover element, which is used to close an insertion opening of the receiving space, to the housing.

The invention comprises a vacuum cleaner filter bag (1), comprising a bag wall (2) and a retaining plate (3), wherein the retaining plate (3) is connected to an at least partially cylindrical connection piece (4) which extends in a direction perpendicular to a passage opening (5) formed in the retaining plate (3), wherein the bag wall (2) is connected with the lateral surface of the connection piece (4) along the circumference thereof.

A filter element has a filter medium annularly surrounding a longitudinal axis of the filter element. The filter medium can be flowed through radially from an exterior to an interior and has a plurality of folds. A first end disk is arranged at a first end face of the filter element. A primary air passage and a secondary air passage are provided. The filter medium has an axial recess at the first end face. The first end disk has a channel forming the secondary air passage and extending in the axial recess. The plurality of folds include first folds in a region of the recess and second folds away from the recess. An axial length of the first folds is reduced relative to an axial length of the second folds. An air filter with such filter element and an assembly method for the air filter are provided.

Proposed is an air purifying filter. The air purifying filter includes a filtering layer (30) configured as a dielectric which collects minute particles, a first electrode layer (50) laminated on a side of the filtering layer (30) and comprising insulated wires (51) to which power is able to be applied, and a second electrode layer (70) laminated on a side of the filtering layer (30) opposite to the side of the first electrode layer and comprising a conductive material such that a polarity opposite to a polarity of the first electrode layer (50) is applied to the second electrode layer or the second electrode layer is grounded.