Filter for Filtering Fluids and Method for Producing the Same

Abstract

A filter includes a filter element ( 1 ) having a filter medium ( 106 ) pleated in a zigzag manner, with a raw side ( 105 ) and a clean side ( 104 ). Filter medium sections ( 120 ), which extend on either side of the raw-side pleat tips ( 102 a ) to adjoining raw-side pleat bases ( 103 a ), include a first bend ( 552 ) toward the raw side ( 105 ), and behind that a second bend ( 554 ) toward the clean side ( 104 ), in each case viewed from the raw-side pleat tips ( 102 a ).

1 . A filter for filtering a liquid or gaseous fluid comprising:
 a filter element with a zigzag-folded filter medium ( 14 ;  106 ) including
 a raw side ( 105 ); 
 a clean side ( 104 ); 
 a plurality of filter medium sections ( 120 ) joined to neighboring filter medium sections ( 120 ) along fold tips ( 102   a ) or fold bases ( 103   a ); 
 said plurality of filter medium sections ( 120 ) extending on both said raw and clean sides from raw-side fold tips ( 102   a ) to neighboring raw-side fold bases ( 103   a ), viewed from said raw-side fold tips ( 102   a ), respectively; 
 wherein at least a portion of said filter medium sections ( 120 ) include a plurality of adhesive lines ( 101 ) arranged thereon at said raw side ( 105 ) and/or at said clean side ( 104 ), each adhesive line ( 101 ) having a first end at said fold tip ( 102   a ) of its filter medium section ( 120 ) and an opposing second end at said fold base ( 103   a ) of its filter medium section ( 120 ) and extending between said fold tip ( 102   a ) of its filter medium section ( 120 ) and said fold base ( 103   a ) of its filter medium section ( 120 ); 
   wherein each adhesive line ( 101 ) having at least two adhesive sections ( 122 ) applied thereon and extending thereon in same direction of said adhesive line ( 101 ) on its filter medium section ( 120 );   wherein said plurality of adhesive sections ( 122 ) are arranged at least sectionwise at a slant or perpendicular to the direction of the fold edges (F); and   wherein each line of adhesive ( 101 ), includes an interruption ( 107 ) in the adhesive arranged between adhesive sections lying on the same adhesive line ( 101 ).   
     
     
         2 . The filter according to  claim 1 , wherein
 said filter medium ( 14 ;  106 ) comprises:
 a support layer; 
 at least one filtration layer arranged at and supported on an inflow side of said support layer; 
 wherein one of said at least one filtration layer is a fine fiber layer of fine fibers; and 
 wherein deposition of particles from said filtered fluid occurs at an inflow side of said fine fiber layer. 
   
     
     
         3 . The filter according to  claim 2 , wherein
 spacing between a plane defined by a plurality of the clean side folds tips ( 102   a ) and a second plane defined by a plurality of raw side fold tips ( 102   b ) is a fold height ( 550 );   wherein said fold height ( 550 ) is at least 50 mm.   
     
     
         4 . The filter according to  claim 2 , wherein
 said fine fibers are any of: microfibers or nanofibers.   
     
     
         5 . The filter according to  claim 2 , wherein
 said support layer is a support grid of polyamide 6.6;   wherein said support grid has a mesh width of between 100 and 150 μm.   
     
     
         6 . The filter according to  claim 4 , wherein
 said at least one filtration layer includes a voluminous ultrafine fiber layer of meltblown fibers with a thickness in the range of 0.01 to 0.3 mm;   wherein said ultrafine fiber layer has an average fiber diameter of approximately 2 μm.   
     
     
         7 . The filter according to  claim 6 , wherein
 said ultrafine fiber layer is selected from the group consisting of polybutylene terephthalate, polycarbonate, polypropylene, polyamide, polyethylene terephthalate, polyvinyl alcohol, polyvinyl nitrate, polyvinyl acetate, polyvinyl halide, polyester, polyalkylene terephthalate, polyalkylene naphthalate or polyurethane.   
     
     
         8 . The filter according to  claim 2 , wherein
 said support layer comprises a cellulose-based filter medium.   
     
     
         9 . The filter according to  claim 2 , wherein
 said support layer is impregnated to be flame resistant.   
     
     
         10 . The filter according to  claim 2 , wherein
 said at least one filtration layer is secured to an inflow side of said support layer by at of: calendaring or an adhesive.   
     
     
         11 . The filter according to  claim 2 , wherein
 at said raw side ( 105 ) a plurality of elongate depressions ( 656 ) are formed in said filter medium ( 14 ;  106 ) that extend between raw-side fold tips ( 102   a ) and raw-side fold bases ( 103   a ) approximately perpendicularly to fold edges (F) of said filter medium ( 14 ;  106 ) and realize at said clean side ( 104 ) corresponding projections ( 658 ) in such a way that in a raw-side intermediate fold space ( 148   a ) two depressions ( 656 ), respectively, are positioned directly opposite each other on two filter medium sections ( 120 ) delimiting said intermediate fold space ( 148   a ) and each form partially a flow passage ( 660 ).   
     
     
         12 . The filter according to  claim 3 , wherein
 said plurality of filter medium sections ( 120 ) including a first bend ( 552 ) toward said raw side ( 105 ) and therebehind a second bend ( 554 ) toward said clean side ( 104 ).   
     
     
         13 . The filter according to  claim 3 , wherein
 said adhesive sections ( 122   a ) have a fixed side arranged on said filter medium and an opposing free side spaced outwardly from said filter medium;   wherein said free sides of said adhesive sections of a first filter medium section ( 120 ) rest against free sides of said adhesive sections of an adjacent filter medium section ( 120 );   wherein said resting free sides supports said first filter medium section ( 120 ) setting a spacing from said adjacent filter medium section ( 120 ) to stabilize folds of the filter element.