Abstract: A filter element for insertion into a housing of a ventilation or air-conditioning system, including a bellows with pleated walls and pleat tips and a front face, which can be faced towards a wall of the housing, wherein a guide duct is allocated to the front face, wherein the guide duct is formed by at least one breakthrough in the pleated walls and/or in a side strip that is hemming the front face, in view of the object to indicate a mechanical coding for a filter element which ensures a unique allocation of a filter element to a housing, wherein the filter element is provided with breakthroughs and wherein the mechanical strength of pleated walls and side strips is impaired as little as possible by the breakthroughs, characterized in that the breakthrough is provided with a reinforcing.

Abstract: A Filter element for insertion into a housing of a ventilation unit or air conditioner, comprising a bellows with folds and a front side, which can face a wall of the housing, wherein the folds on the front side define fold cross-sectional surfaces, wherein to the front side at least one guiding slot is assigned and wherein a fold cross-sectional surface has a geometry in the area of a guiding slot that is different from the fold cross-sectional surface of a multiplicity of folds, is, in view of the task of providing an efficient filter element which, after problem-free manufacture is equipped with guiding slots into which guide pins can be inserted, characterized in that a multiplicity of regular fold walls is provided, wherein each two flanking walls flank the guiding slot.

Abstract: A filter element for insertion into a housing of a ventilation or air-conditioning system, comprising a bellows with pleated walls and pleat tips and a front face, which can be faced towards a wall of the housing, wherein a guide duct is allocated to the front face, wherein the guide duct is formed by at least one breakthrough in the pleated walls and/or in a side strip that is hemming the front face, in view of the object to indicate a mechanical coding for a filter element which ensures a unique allocation of a filter element to a housing, wherein the filter element is provided with breakthroughs and wherein the mechanical strength of pleated walls and side strips is impaired as little as possible by the breakthroughs, characterized in that the breakthrough is provided with a reinforcing.

Abstract: A Filter element for insertion into a housing of a ventilation unit or air conditioner, comprising a bellows with folds and a front side, which can face a wall of the housing, wherein the folds on the front side define fold cross-sectional surfaces, wherein to the front side at least one guiding slot is assigned and wherein a fold cross-sectional surface has a geometry in the area of a guiding slot that is different from the fold cross-sectional surface of a multiplicity of folds, is, in view of the task of providing an efficient filter element which, after problem-free manufacture is equipped with guiding slots into which guide pins can be inserted, characterized in that a multiplicity of regular fold walls is provided, wherein each two flanking walls flank the guiding slot.

Abstract: A filter element includes a filter web pleated in an essentially zigzag manner and made, in particular, of a nonwoven material, for insertion into a holder such as a filter frame and/or a filter housing, having at least one end-positioned wall of an essentially flat design. The filter element includes at least one end face, viewed in the direction of the pleats. To achieve a tighter seal, the end face of the filter element is curved outward in a defined convex manner, and the filter web material is selected and/or its end face conditioned so that, when inserted into the holder, the end face of the filter web may be placed leak-tight against the end wall of the holder without corrugation under elastic pre-tension.

Abstract: A filter element includes a filter web pleated in an essentially zigzag manner and made, in particular, of a nonwoven material, for insertion into a holder such as a filter frame and/or a filter housing, having at least one end-positioned wall of an essentially flat design. The filter element includes at least one end face, viewed in the direction of the pleats. To achieve a tighter seal, the end face of the filter element is curved outward in a defined convex manner, and the filter web material is selected and/or its end face conditioned so that, when inserted into the holder, the end face of the filter web may be placed leak-tight against the end wall of the holder without corrugation under elastic pre-tension.