Plate heat exchanger

Claim 1

A heat exchanger, comprising substantially rectangular plates in alignment with one another and provided by embossing with a bead-like profile of uniform total depth, said plates being alternatingly rotated by 180° relative to one another and having a peripheral gasket disposed therebetween and further being fastened detachably into a stack with the facing profiles of adjacent plates resting on one another in opposed relation, wherein the plates alternatingly form flow spaces, encompassed by the peripheral gasket, for a first medium and a second medium guided substantially parallel to the first, the flow spaces being supplied with the respective medium via inlet and outlet openings in alignment with one another and formed by means defining openings disposed in the corner regions of the plates, the plates further having a middle rectangular heat exchange zone and two triangular heat exchange zones adjoining the middle zone on opposite sides, said triangular zones transfer the flow section of the middle zone to the vicinity of the inlet and outlet opening, to which end the profile of the triangular zones is embodied substantially as rays originating at the opening and having a pitch defining a mutual spacing, characterized in that said rays of one triangular zone (21, 32) comprise a profile having regular sections (22, 23; 34, 35) having the pitch of the ray spacing and adjoining one another in the direction of the rays and embossed alternatingly in opposite directions out of the plane of a plate, with the embossing depth originating at the plane of the plate (20, 31, 36-39), and further that the rays of the other triangular zone (25), along where they are covered by the rays, rotated by 180°, of the first triangular zone, have a profile having sections (26, 27) corresponding to that of the first triangular zone but embossed in the opposite direction.