Patent ID: 7540895

Claim:
A filter comprising: a housing having an inlet and an outlet; a first flow passage through said housing from said inlet to said outlet, and including a first filter element filtering fluid flowing along said first flow passage; a second flow passage through said housing from said inlet to said outlet, and including a second filter element filtering fluid flowing along said second flow passage; said first and second flow passages being in parallel with each other such that incoming fluid flow at said inlet is split into first and second parallel flow paths in said first and second flow passages, respectively, and flows through said first and second filter elements, respectively, and re-joins at said outlet, wherein: said housing comprises an internal dividing wall separating said first and second flow passages such that fluid in said first flow passage flows through said first filter element to the exclusion of and bypassing said second filter element, and such that fluid in said second flow passage flows through said second filter element to the exclusion of and bypassing said first filter element; said first filter element has an upstream face receiving incoming fluid along said first flow passage from said inlet, and a downstream face delivering filtered fluid along said first flow passage to said outlet; said second filter element has an upstream face receiving incoming fluid along said second flow passage from said inlet, and a downstream face delivering filtered fluid along said second flow passage to said outlet; said first and second filter elements are spaced from each other by a gap; said internal dividing wall comprises a diagonal wall which diagonally spans said gap and defines an upstream triangular shaped plenum having a closed corner end at said upstream face of said second filter element, and having an open end communicating with said inlet, and defines a downstream triangular shaped plenum having a closed corner end at said downstream face of said first filter element, and having an open end communicating with said outlet; said diagonal wall has a non-rectilinear wave shape providing increased entrance area at said open end of said upstream triangular shaped plenum and reduced area at said closed corner end of said upstream triangular shaped plenum, and providing increased exit area at said open end of said downstream triangular shaped plenum and reduced area at said closed corner end of said downstream triangular shaped plenum.