Plate for stack type heat exchangers and heat exchanger using such plates

The present invention relates generally to a plate for stack type heat exchangers and heat exchanger using such plates. In particular, the present invention relates to a plate for stack type heat exchangers and heat exchanger using such plates, which is capable of improving its performance of heat exchange by preventing the non-uniform flow distribution of refrigerant and increasing the turbulent flow effect of refrigerant, achieving its miniaturization and its optimal performance of heat exchange by designing the width of the plate and the arrangement of protrusions in accordance with an improved regularity, and improving its durability by enhancing the strength of attachment of its U-turn portion. Disclosed is a plate for stack type heat exchangers and heat exchanger using such plates. A plurality of small protrusions formed on the plate are regularly arranged in the pattern of a diagonal lattice so that the ratio of the area S of the rectangle (which is defined by the longitudinal partition protrusion, a flange and two center lines passing through two neighboring round protrusion rows) to the width L of the plate falls within the range of 0.89 mm S/L 1.5 mm. The outlet-side flange portion of the flange of the plate and a round protrusion of the round protrusions nearest to the outlet-side flange portion are preferably arranged so that the width Gs of the passage between the outlet-side flange portion and the nearest round protrusion falls within the range of 0.15 mm Gs 1.6 mm. The several round reinforcing protrusions A are preferably situated along the lower, imaginary prolongation line of the longitudinal partition protrusion while being arranged together with the other round protrusions in the pattern of a diagonal lattice, at least one of upper protrusions of the several round reinforcing protrusions having a greater size than the size of the other round reinforcing protrusions. Two diagonal protrusions are preferably and respectively formed on both corners of the U-turn portion. A spacer inserted around the manifold portion of the manifold tubes can increase the bending moment stress of the manifold portion.