| 摘要 |
PURPOSE:To raise the efficiency of heat transfer and to improve the sealing performance of air passages, by forming side wall portions at the peripheral section of each heat exchanger plate, and coupling the side wall portions of the heat exchanger plates in the manner that air passages are formed between the heat exchanger plates. CONSTITUTION:Respective side wall portions 13, 14 of heat exchanger plates 11, 12 are enlarged at their lower half sections for forming projections by the intermediary of steps 15, 16, so that these heat exchanger plates 11, 12 are superposed alternately on each other by fitting lower-half enlarged sections 13a, 14a of the side walls 13, 14 of respective heat exchanger plates 11, 12 onto upper-half wall sections 13b, 14b formed at the base portions of the side walls 13, 14 of the mating heat exchanger plates 11, 12. In the above arrangement, primary and secondary air passages 17, 18 are formed between the heat exchanger plates 11 and 12, with the depth of fit being kept constant by bringing the lower ends of the side walls 13, 14 into abutment with the mating steps 15, 16. |
