Patent ID: 6953009

Claim:
A vaporizer comprising: a plurality of fuel flow structures, each comprising two abutting fuel flow sheets sandwiched between first separator sheets, said fuel flow sheets having elongated slots therein extending at a progressively decreasing angle to a mean direction of fuel flow through said fuel flow structures and with increasing widths from one end of the fuel flow sheet to the other, the slots in one fuel flow sheet being in criss-cross relation with the slots in the other fuel flow sheet; a plurality of heated medium flow structures comprising a fin sandwiched between two second separator sheets, each second separator sheet extending beyond said ends of said fuel flow sheets and having first enlarged openings therein in alignment with one another at locations beyond said fuel flow sheet ends, said fuel flow structures and said heated medium structures being located in a stack in alternating relation with the fuel flow structures in the stack being aligned with one another and the heated medium structures in the stack being aligned with one another, a common fuel inlet to said fuel flow structures on a side of said fuel flow sheets near said one of said ends; a common fuel outlet from said fuel flow structure on a side of said fuel flow sheets near said other of said ends; second, aligned enlarged openings in said fuel flow sheets at said other end and intersecting some of said slots and connected to said common fuel outlet; a highly flow resistant maze in each of said fuel flow sheets at said one end and intersecting others of said slots and connected to said common fuel inlet, a common heated medium inlet at an end of said plurality of fuel flow structures and in fluid communication with said first enlarged opening thereat; and a common heated medium outlet at an end of said plurality of fuel flow structures and in fluid communication with said first enlarged openings thereat, said heated medium outlet being spaced from said heated medium inlet.