FLUID FILTER WITH SECONDARY FILTER ELEMENT OF LIGHTWEIGHT CONSTRUCTION

The invention relates to a fluid filter (10) for filtering a fluid, in particular air, comprising a filter housing (12) having a central support tube (22) which extends along a longitudinal axis (16)of the filter housing (12) within the filter housing (12) and a primary filter element (24) arranged inside the filter housing (12) in an exchangeable manner. There is a secondary filter element (26)positioned inside the filter housing (12) which serves as a safety-element during a replacement of the primary filter element (24). A sealing between a first end portion of the secondary filter element (26) and the filter housing (12) is effected partially or solely by the filter medium (28) of the secondary filter element (26). The first end portion of the secondary filter element may engage in agroove-shaped retaining structure of the filter housing (12). The invention further relates to a secondary filter element (26) for such a fluid filter (10). 本发明涉及一种用于过滤流体、具体地空气的流体过滤器（10），该流体过滤器包括：过滤器壳体（12），其具有中央支撑管（22），该中央支撑管在