Filter unit for filtering gaseous fluids

Abstract

The invention relates to a filter unit for filtering gaseous fluids, comprising a filter insert part with a filter medium and a sealing element, said element being clamped between sealing struts on parts of the filter housing. The clamping force produced by the sealing struts that lie opposite one another runs at least approximately perpendicularly to the mounting direction of the housing parts.

The invention claimed is: 
     
       1. An air filter unit for filtration of gaseous fluids, comprising:
 a filter housing ( 9 ) having a longitudinal axis, said filter housing including a first housing part ( 10 ) including an axially extending first sealing stay ( 13 ), said sealing stay including a contact surface; 
 a second housing part ( 11 ) including
 an axially extending second sealing stay ( 14 ) arranged radially outwardly of said first housing part ( 10 ) sealing stay ( 13 ), said second housing part ( 11 ) detachably joined to said first housing part in a mounting direction, said second sealing stay including a contact surface; 
 
 a filter insert part ( 1 ) including a raw flow face and a clean flow face, said filter insert part ( 1 ) inserted into said housing ( 9 ), said filter insert part ( 1 ) including
 a filter medium ( 2 ); and 
 a sealing element ( 3 ) arranged on a radial outer circumference of said filter medium at one of said flow faces, said sealing element extending radially outwardly from said outer circumference, 
 said sealing element ( 3 ) secured to said filter medium; 
 
 wherein said first housing part includes
 a connecting section ( 16 ) having a first end secured to an outwardly facing side of said sealing stay ( 13 ), said connecting section ( 16 ) extending radially outwardly from said sealing stay ( 13 ); 
 a support stay ( 15 ) secured to an opposing second end of said connecting section ( 16 ), said sealing stay ( 13 ) with said connecting section ( 16 ) and said support stay ( 15 ) forming a U-shaped receiving space ( 17 ) surrounding an outer side of said first housing part ( 10 ); 
 
 wherein said second sealing stay ( 14 ) of said second housing part ( 11 ) is receiving received into said U-shaped receiving space ( 17 ), such that said second sealing stay (14) is received between and radially spaces apart said support stay (15) from said sealing element (3); 
 wherein said first sealing stay ( 13 ) separates an interior of said first housing part ( 10 ) from said U-shaped receiving space ( 17 ); 
 wherein a portion of said sealing element ( 3 ) is clamped between said contact surface of sealing stays ( 13 ,  14 ) of said housing parts ( 10 , 11 ) in said U-shaped receiving space ( 17 ); 
 whereinwherein the sealing element (3) is radially compressed by and radially compressed between the first sealing stay (13) of the first housing part (10) and the second sealing stay (14) of the second housing part (11), said contact surfaces of radially spaced first and second sealing stays ( 13 ,  14 ) exert a clamping force radially compressing said sealing element ( 3 ), said clamping force extending approximately orthogonally to said mounting direction of said housing parts ( 10 ,  11 ). 
 
     
     
       2. The air filter unit according to  claim 1 , wherein
 said contact surfaces on the sealing stays ( 13 ,  14 ) that load said sealing element ( 3 ) are positioned at an angle of maximally 30 degrees relative to each other. 
 
     
     
       3. The air filter unit according to  claim 1 , wherein
 said contact surfaces on said sealing stays ( 13 ,  14 ) are at least approximately parallel to each other. 
 
     
     
       4. The air filter unit according to  claim 1 , wherein
 said second sealing stay ( 14 ) projects into said receiving space ( 17 ) and rests immediately on said sealing element ( 3 ) when said housing parts ( 10 ,  11 ) are in a detachably mounted state. 
 
     
     
       5. The air filter unit according to  claim 4 , wherein
 said second sealing stay ( 14 ) is positioned parallel to said support stay ( 15 ), and 
 wherein said support stay ( 15 ) forms a glide surface for said second sealing stay ( 14 ) during mounting. 
 
     
     
       6. The air filter unit according to  claim 1 , wherein said first sealing stay ( 13 ) facing said filter medium ( 2 ) and said support stay ( 15 ) are formed monolithically with each other. 
     
     
       7. The air filter unit according to  claim 1 , wherein said receiving space ( 17 ) receiving said sealing element ( 3 ) is immediately delimited by said first and second sealing stays ( 13 ,  14 ). 
     
     
       8. The air filter unit according to  claim 1 , wherein said sealing element ( 3 ) engages said first sealing stay ( 13 ) facing said filter medium ( 2 ). 
     
     
       9. The air filter unit according to  claim 8 , wherein said sealing element ( 3 ) has a bendable sealing lip that in the mounted state is wrapped about said first sealing stay ( 13 ) facing said filter medium. 
     
     
       10. The air filter unit according to  claim 1 , further comprising:
 an additional sealing member ( 26 ) arranged between one of said housing parts ( 10 ,  11 ) and said sealing element ( 3 ), 
 wherein said additional sealing member ( 26 ), relative to said contact surface between the second sealing stay ( 14 ) facing away from the filter medium ( 2 ) and said sealing element ( 3 ), is displaced toward a clean side of said filter medium ( 2 ). 
 
     
     
       11. The air filter unit according to  claim 1 , wherein said second sealing stay ( 14 ) on said second housing part ( 11 ) and a sealing stay or support stay ( 15 ) on said first housing part ( 10 ) positive-lockingly engage each other in the manner of a tongue-and-groove connection. 
     
     
       12. The air filter unit according to  claim 1 , wherein at least one of said sealing stays ( 13 ,  14 ) is overlapped by a snap hook ( 19 ) that is formed monolithically together with one of said housing parts ( 10 ,  11 ) and is movable into a snap connection with said other housing part ( 10 ,  11 ). 
     
     
       13. A filter insert part suitable for use in an air filtration unit of claim 1, the filter insert part comprising:
 a filter medium (2) folded in a zigzag shape and embodied in a plate shape, the filter medium having
 a raw flow face through which a gaseous fluid to be filtered enters the filter medium, said raw flow face arranged at a first axial side of said filter medium; 
 a clean flow face through which a filtered gaseous fluid leave the filter medium, the clean flow face arranged at an opposing second axial side of said filter medium; 
 at least one lateral side of said filter medium, said at least one lateral side extending between said raw flow face and said clean flow face; 
   a sealing element (3) comprising:
 a circumferentially extending stay (5) arranged on and secured onto a radial outer circumference of said filter medium at a first one of said flow faces, said sealing element circumscribing and circumferentially closing around said first flow face on said radial outer circumference, said stay including
 a first leg arranged on and extending radially inwardly on said first flow face: 
 a second leg arranged on said at least one lateral side of said filter medium: 
 
 a sealing tongue (6) formed with said circumferentially extending stay (5) and projecting away from said stay in an axial direction towards an opposing second one of said flow faces, the sealing tongue including
 an axially extending inner sealing surface on a side of said sealing tongue facing said filter medium; 
 an outer sealing surface on an opposing side of said sealing tongue, said outer sealing surface facing away from said filter medium; 
 wherein said inner and said outer sealing surfaces are configured and adapted for engaging a housing and be compressed radially by the housing during installation for forming radially acting seals at said inner and said outer sealing surfaces with the housing; 
 
 wherein the second leg and the sealing tongue (6) are spaced apart forming opposing sidewalls of a receiving groove in the sealing element, the sealing groove adapted to receive a sealing stay (13) of the filter housing; 
 wherein said sealing tongue (6) extends axially beyond said second leg. 
   
     
     
       14. The filter insert part according to claim 13, wherein
 said sealing tongue (6) is a flexible and deformed by opposing radially acting forces, radially deforming and compressing said sealing tongue (6), said deformation generating radially outwardly acting forces within said sealing tongue (6) operable for forming two oppositely acting radial seals with the housing at said outer sealing surface and said inner sealing surface.   
     
     
       15. The filter insert part according to claim 13, wherein
 said circumferentially extending stay (5) forms a base of said receiving groove connecting said opposing sidewalls of said receiving groove;   wherein said base is configured and adapted for sealably engaging against a sealing stay of the housing when the filter insert is installed.   
     
     
       16. The filter insert part according to claim 13, wherein
 said sealing element with said sealing tongue and said first and second legs are formed as a unitary one piece component;   wherein said sealing element is injection molded immediately onto the filter medium.   
     
     
       17. The filter insert part according to claim 13, wherein
 said filter medium comprises filter paper.   
     
     
       18. The filter insert part according to claim 13, wherein
 said sealing element is embodied as a PUR foam seal, said PUR foam seal directly injection molded onto said filter medium or foamed onto the filter medium.