Multilayered flat heat exchanger

Claim 1

A multilayered flat heat exchanger, comprising a plurality of concentrically disposed substantially square hollow flat shells, each shell being vertically elongated and made of a pair of identical halves, which halves are joined together so as to enclose a next inwardly adjacent shell with a spacing therefrom, at least one inverse-U-shaped passage being formed within each odd numbered shell, as sequentially counted from the innermost shell, which is referred to as number one, and at least one straight passage being disposed between adjacent inverse-U-shaped passages, each said inverse-U-shaped passage being completely isolated from any of the straight passages and being equipped with an inlet opening and an outlet opening, each said straight passage being completely isolated from any of the inverse-Ushaped passages and being equipped with an inlet opening and an outlet opening, said shells at least including a first shell located at the innermost portion of the heat exchanger and having a horizontal inlet opening slightly projecting outwardly from the periphery of the first shell at one end of the bottom edge thereof, a horizontal outlet opening slightly projecting outwardly from the periphery of the first shell at the opposite end of the bottom edge thereof, and a central partition extending vertically within the shell from the central portion of the bottom edge to the proximity of a top edge of the first shell, so as to define an inverse-Ushaped passage communicating therethrough the horizontal inlet opening with the horizontal outlet opening; at least one even numbered shells, as counted from the innermost shell, each enclosing a next inward shell with a spacing therefrom and having a vertical inlet opening slightly projecting outwardly from the periphery thereof at one end of the vertical center line thereof, a vertical outlet opening slightly projecting outwardly from the periphery thereof at the opposite end of the vertical center line, and a pair of fitting openings formed at opposite ends of the bottom edge of each even numbered shell, said fitting openings sealingly engaging the outer surfaces of the horizontal inlet and outlet openings of the next inward shell, respectively, so as to completely separate the inside of the next inward shell from the space between each even numbered shell and the next inward shell, said space between each even numbered shell and the next inward shell forming a vertical passage communicating therethrough the vertical inlet opening with the vertical outlet opening, respectively; and at least one odd numbered shells, as counted from the innermost shell, each enclosing a next inside shell with a spacing therefrom and having a horizontal inlet opening slightly projecting outwardly from the periphery thereof at one end of the bottom edge thereof, a horizontal outlet opening slightly projecting outwardly from the periphery thereof at the opposite end of the bottom edge thereof, and a pair of fitting openings formed at opposite ends of a vertical centerline Of each odd numbered shell, said fitting openings sealingly engaging the outer surfaces of the vertical inlet and outlet openings of the next inward shell, respectively, so as to completely separate the inside of the next inward shell from the space between each odd numbered shell and the next inward shell, said space between each odd numbered shell and the next inward shell forming an inverse-U-shaped passage communicating therethrough the horizontal inlet opening with the horizontal outlet opening, respectively