Stacked-plate heat exchanger

Claim 1

A heat-exchanger sandwich construction for accommodating two fluids separately flowing in different directions, said construction comprising a plurality of like flat rectangular metal plates providing heat-exchange surfaces, and spacer means between adjacent plates and retaining said plates in spaced parallel relation; the spacer means between first and second successive plates of said plurality comprising a first pair of parallel rail members along a first pair of opposed parallel edges of said first and second plates, thereby establishing a first-passage flow direction through said construction; the spacer means between said second and the third successive plate of said plurality comprising a second pair of parallel rail members along the other opposed parallel edges of said second and third plates, thereby establishing a second-passage flow direction orthogonal to said first direction and through said construction; the spacer means between similarly successive plates comprising further of said first parallel rail members and further of said second parallel rail members in alternating succession, thereby establishing flows in said first and second directions in interlaced layers through said construction, so that each plate separates and serves the respective fluid flows in their orthogonally related directions; said spacer means including between parallel rail members of one of said pairs a longitudinally extruded metal plate that is characterized on both sides by spaced parallel grooves between longitudinal ridges, the longitudinal direction of the grooves and ridges being parallel to the involved rail members, and all rail members and ridges having bonded direct supporting contact with both of the adjacent plates which they space.