Corrugated spacers for pleated air filter media

Claim 1

An article of manufacture in the form of a corrugated spacer for pleated filter media, said spacer comprising: (a) a rectangular sheet of aluminum having a thickness between about 1 to 2 mils and a hardness of not less than H19; (b) said sheet being folded in zig-zag fashion with successive folds at evenly spaced intervals forming a succession of V formations along each of first and second opposite edges of said sheet; (c) the amplitude and frequency of said V formations along said first edge being substantially constant, first and second dimensions respectively; (d) the number of said V formations within a given linear width along said second edge being five times the number within the same width along said first edge, whereby the amplitude and frequency of said V formations along said second edge are substantially 1/5 of said first and second dimensions respectively; (e) the fold lines forming said V formations along said first edge extending completely between said first and second edges, parallel to one another and to the third and fourth edges of said sheet; and (f) wherein the fold lines forming said V formations along said second edge, in addition to said fold lines extending completely between said first and second edges, extend from said second edge for about 80% to 90% of the distance to said first edge, at which point they merge into the surface of said sheet, substantially parallel to one another and to said fold lines extending completely between said first and second edges, said spacer being essentially free of cracks and breaks.