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.

Collapsible filter assembly includes a filter medium element and a frame at least partially surrounding the filter medium element. The frame and filter media element are configured to vary in at least two dimensions by folding or unfolding. In at least on example, the filter medium element is rectangularly pleated or round pleated. Upon removal of the filter assembly from packaging and other restraints, the filter assembly may naturally expand with regard to footprint and volume, with some manual assistance being expected of a typical user in unfolding from an area-reduced configuration to an area-expanded configuration, and from a volumetrically reduced configuration to a volumetrically expanded configuration.

A filter element for an air filter has a filter bellows with a filter medium folded multiple times. A recess is disposed in the filter bellows and is designed to receive a guiding rib of the air filter. The recess is curved at least in sections thereof along a length extension of the recess. The air filter has a housing and a guiding rib, wherein the filter element is arranged at least partially in the housing and the guiding rib is immersed at least partially in the recess of the filter element. In a method for producing the filter element, the recess in the filter bellows is formed with a computer-assisted separation method that forms the recess to be curved at least in sections thereof.

The present teachings include a fibrous structure including one or more nonwoven layers comprising a fibrous web layer and one or more functional insert layers for providing additional properties to the material. The one or more of the nonwoven layers and one or more functional insert layers may be lapped together to form a vertically lapped structure. The present teachings also include a method of forming the fibrous structure.

An air purifier filter is proposed. The air purifier filter includes: a filter body having an inlet and an outlet therein such that air flows therethrough, and a receiving space having formed therein; a substrate provided in the receiving space of the filter body; and activated carbon attached to a surface of the substrate, wherein the substrate has a three-dimensional corrugated structure.

An air filter element for an air filter for an internal combustion engine is provided with a filter medium surrounding annularly a longitudinal axis of the air filter element. A first end disk is provided at a first end face of the air filter element, wherein the filter medium is embedded in the first end disk at the first end face. A clean air seal is configured to seal a raw side of the air filter against a clean side of the air filter. The clean air seal and the first end disk are embodied together as one piece. The clean air seal protrudes continuously radially past the filter medium. A filter housing for the air filter element is provided with a filter pot and a cover and has a clean air outlet and a raw air inlet arranged at a side wall of the filter pot.

A dust extraction unit is disclosed including a first and a second air filter removable and mountable within the dust extraction unit and a body defining an air flow path which passes through the first and the second air filters when the first and the second air filters are mounted within the body of the dust extraction unit. The body of the dust extraction unit comprises a first portion operable to receive the first air filter and a second portion operable to receive the second air filter. The first and second portions are connected by a hinge so that the first portion is moveable between a first configuration in which the first and second portion define an air flow path though the dust extraction unit and a second configuration which provides access to the portion of the dust extraction unit operable to receive the second air filter.

A cover for a filter system for filtering a fluid has a fluid channel arranged at an inner side of the cover. The cover has a rim and at least one opening arranged in the rim to allow the fluid to pass through, wherein the opening is connected in fluid communication with the fluid channel. The fluid channel is connected in fluid communication with the interior of a filter element of the filter system. A seal for the cover has a first sealing ring and a second sealing connected to each other by flanks. The filter system has a housing with a housing part that is closable by the cover. A filter element is exchangeably arranged in the housing, and the fluid channel of the cover is connected in fluid communication to the interior of the filter element.

A filter module with a perforated inner tube (20) and a concentric, perforated outer tube (22), forming an interposed annular gap for a filter membrane (10) pleated into folds. The membrane folds (11, . . . ) are of different fold types with differing fold heights, extend from a respective fold edge (111, . . . ) resting against the outer tube towards the inner tube to the respective fold tip (114, . . . ) and are arranged along the circumference of the annular gap as groups of folds (11, . . . ) of different types. Each group has a mating fold (15) which extends from a mating fold edge (151) resting against the inner tube towards the outer tube to the mating fold tip (154). The height of the mating fold is no more than the difference between the width of the annular gap and the height of the fold type with the shortest height of the same group.

A filter media pack with pleat folds, pleat panels and a plurality of glue bead sections is provided. The glue bead sections provide increased rigidity, dimensional stability and maintain spacing between adjacent pleat panels. Methods of manufacturing the filter media packs are provided. Filter elements including the filter media packs are contemplated.