Pleated Sintered Metal Fiber Medium

Abstract

A sintered metal fiber medium as subject of the invention comprising at least one pleat, which pleat comprising a first leg being present according to a first plane, and a second leg being present according to a second plane. The first plane and the second plane intersect along an intersecting line according to a dihedral angle θ. The pleat comprises a bending part for coupling the first and the second leg. The medium has an average thickness at the legs of TI. A sintered metal fiber medium as subject of the invention is characterized in that the bending part comprises at least one distinct linear zones, which is substantially parallel to the intersecting line, in which linear zone, the medium has a minimum thickness Tb, which Tb is smaller than TI. In the linear zone or zones of the bending part, the thickness of the medium is reduced, so Tb is less than 0.5 times TI. Further, a method to provide such pleated sintered metal fiber medium is described.

1 . A sintered metal fiber medium comprising at least one pleat, said pleat comprising a first leg, said first leg being present according to a first plane, said pleat comprising a second leg being present according to a second plane, said first plane and said second plane intersecting along an intersection line at a dihedral angle θ, said pleat comprising a bending part for coupling said first and said second leg, said medium having an average thickness at said legs of TI, said bending part comprises at least a first distinct linear zones being substantially parallel to said intersecting line, in which first linear zone said medium having a minimum thickness Tb, said Tb is smaller than said TI, characterized in that Tb is smaller than 0.5 times TI.  
     
     
         2 . A sintered metal fiber medium as claimed in  claim 1 , wherein Tb is smaller or equal to 0.45 times TI.  
     
     
         3 . A sintered metal fiber medium according to  claim 1 , wherein said first linear zone has a width W being larger than or equal to TI-Tb.  
     
     
         4 . A sintered metal fiber medium according to  claim 1 , wherein said bending part comprises only one distinct zone.  
     
     
         5 . A sintered metal fiber medium according to  claim 4 , wherein said dihedral angle θ is smaller than 180°, said dihedral angle θ being larger than 90°.  
     
     
         6 . A sintered metal fiber medium according to  claim 1 , wherein said bending part comprises a second distinct zones, said zoned being substantially parallel to each other.  
     
     
         7 . A sintered metal fiber medium according to  claim 6 , wherein said dihedral angle θ is smaller than 90°.  
     
     
         8 . A sintered metal fiber medium according to  claim 6 , wherein minimum thickness Tb is substantially equal to the minimum thickness of said second zone.  
     
     
         9 . A sintered metal fiber medium according to  claim 6 , wherein said width W is substantially equal to width of said second zone.  
     
     
         10 . A sintered metal fiber medium according to  claim 6 , wherein the distance D between said first and said second liner zones is equal or larger than the largest of said width W of said first zone and the width of said second zone.  
     
     
         11 . A sintered metal fiber medium according to  claim 10 , wherein D is in the range of W to 5 times TI.  
     
     
         12 . A method to pleat a sintered metal fiber medium, said method comprising the steps of: 
 Providing a sintered metal fiber medium having a thickness TI;    Reducing the medium thickness over at least a first linear zone to a thickness Tb, Tb being the minimum thickness measured at said linear zone, said Tb being smaller than 0.5 times TI;    Bend the medium parts present at both sides of said linear zone to the same side of the medium, using said linear zone as bending axes, in order to obtain a first legs being present according to a first plane and a second leg being present according to a second plane, said first and said second plane intersecting along an intersection line at a dihedral angle θ.    
     
     
         13 . A method to pleat a sintered metal fiber medium as claimed in  claim 12 , wherein Tb is smaller of equal to 0.45 times TI.  
     
     
         14 . A method to pleat a sintered metal fiber medium as claimed in  claim 12 , wherein said first linear zone has a width W being larger or equal to TI-Tb.  
     
     
         15 . A method to pleat a sintered metal fiber medium as claimed in  claim 12 , wherein said dihedral angle θ is smaller than 180°, said dihedral angle θ being larger than 90°.  
     
     
         16 . A method to pleat a sintered metal fiber medium as claimed in  claim 12 , wherein said medium thickness is reduced over a first and a second linear zone, said linear zones being substantially parallel.  
     
     
         17 . A method to pleat a sintered metal fiber medium as claimed in  claim 16 , wherein said dihedral angle θ is smaller than 90°.  
     
     
         18 . A method to pleat a sintered metal fiber medium as claimed in  claim 16 , wherein said first linear zone and said second linear zone has a width being larger or equal to TI-Tb.  
     
     
         19 . A method to pleat a sintered metal fiber medium as claimed in  claim 18 , wherein said widths of said first and said second linear zone are substantially equal.  
     
     
         20 . A method to pleat a sintered metal fiber medium as claimed in  claim 18 , wherein the distance D between said linear zones is the largest of said width of said first zone and the width of said second zone.  
     
     
         21 . A method to pleat a sintered metal fiber medium as claimed in  claim 20 , wherein D is in the range of W to 5 times TI.