Folded Filter Media Pack with Varying Channels and Deep Corrugations

Abstract

Filter media packs that utilizes a zig-zag folding pattern on deeply corrugated filter media are described. The filter media is scored, folded, and secured into position to form the filter media pack. The filter media pack may be secured using a self-supporting structure (e.g., via tacking adhesive used to secure adjacent folds). The filter media pack contains unique features to optimize filtration performance, such as maximized inlet and outlet face flow areas. In some arrangements, the filter media pack exhibits improved flow characteristics and dust-holding capacity via upstream and downstream channels that have different cross-section al shapes and/or sizes. The upstream and downstream channels may comprise, for example, circular, diamond shaped, or fish-scale shaped openings.

1 - 20 . (canceled) 
     
     
         21 . A filter media pack comprising:
 filter media scored and folded in so as to form a plurality of flow channels, each of the plurality of flow channels having a plurality of scores at a plurality of bend axes, the filter media is alternately folded at each of the plurality of bend axes so as to form the filter media pack having a plurality of upstream openings defined by a first plurality of score lines and a plurality of downstream openings defined by a second plurality of score lines.   
     
     
         22 . The filter media pack of  claim 21  wherein the plurality of upstream openings have a 22 different cross-sectional shape than the plurality of downstream openings. 
     
     
         23 . The filter media pack of  claim 22  wherein the plurality of upstream openings are substantially oval shaped. 
     
     
         24 . The filter media pack of  claim 23  wherein the plurality of downstream openings are substantially diamond shaped. 
     
     
         25 . The filter media pack of  claim 22  wherein the plurality of downstream openings are substantially diamond shaped. 
     
     
         26 . The filter media pack of  claim 22  wherein the plurality of upstream openings are larger than the plurality of downstream openings. 
     
     
         27 . The filter media pack of  claim 21  wherein the plurality of upstream openings are fish scale shaped. 
     
     
         28 . The filter media pack of  claim 21  wherein the plurality of downstream openings are fish scale shaped. 
     
     
         29 . The filter media pack of  claim 21  wherein the plurality of upstream openings and the plurality of downstream openings are fish scale shaped. 
     
     
         30 . The filter media pack of  claim 21  wherein the upstream openings and the downstream openings are diamond shaped. 
     
     
         31 . The filter media pack of  claim 21  wherein the plurality of flow channels are triangular in cross-section such that, when the filter media is alternately folded at the plurality of bend axes, a plurality of diamond shaped flow channels are formed. 
     
     
         32 . The filter media pack of  claim 21  wherein the first plurality of score lines are inwardly arched. 
     
     
         33 . The filter media pack of  claim 32 , wherein the plurality of upstream openings are circular. 
     
     
         34 . The filter media pack of  claim 21  wherein the second plurality of score lines are outwardly arched. 
     
     
         35 . The filter media pack of  claim 34 , wherein the plurality of downstream openings form a substantially oval shape. 
     
     
         36 . The filter media pack of  claim 21  wherein the plurality of upstream openings are larger than the plurality of downstream openings. 
     
     
         37 . The filter media pack of  claim 32 , wherein the second plurality of score lines are outwardly arched. 
     
     
         38 . The filter media pack of  claim 21  wherein the plurality of upstream openings are defined by the first plurality of score lines that form a substantially diamond shape with inwardly arched sides. 
     
     
         39 . The filter media pack of  claim 38 , wherein the plurality of downstream openings are defined by the second plurality of score lines that form a substantially oval shape. 
     
     
         40 . The filter media pack of  claim 21  further comprising a tacking material positioned between adjacent crests of the plurality of flow channels, the tacking material holding the filter media pack in a desired shape.