Abstract: A heat exchanger core is formed by a plurality of stacked plates which are rectangular so as to define two fluid paths at right angles passing between alternate ones of the plates. The core is constructed by defining walls extending at right angles from the side edges of one of the plates and an inturned flange at the extremity of each wall. The inturned flange cooperates with a slot defined by a pair of folded portions of the next adjacent sheet so that the core is assembled by sliding two opposed slots along the cooperating flanges of the next adjacent sheet. A corner member has projections from the edges of a pair of right angle strips which projections extend into the core alternately into one fluid path and the next adjacent fluid path. Side support members similarly include a flat strip and projections into the fluid paths of the core.

Abstract: A heat exchanger includes a core structure formed by a plurality of plate members in stacked arrangement. Each plate member is square or rectangular and includes along two opposed sides a portion bent at right angles to the basic plate and then bent inwardly to wrap around the next adjacent plate member. The other two sides of the plate member are bent in the opposite direction and then turn inwardly to act as spacers to hold each plate member from the next by a predetermined dimension thus defining cells between each plate member and the next adjacent plate member. This core construction is then assembled in a plurality of separate core members into a frame structure defined by a pair of side frames defining rails along which the core members can slide. The core members are compressed inwardly by a pair of end doors leaving open top and bottom open sides of the frame structure for connection to suitable duct work.