Plate-type heat exchanger

Abstract

A plate-type heat exchanger includes a plurality of heat exchange units stacked on each other. Adjacent heat exchange units are disposed in such a manner that a projection plane of a through hole in one heat exchange unit does not overlap a through hole in another heat exchange unit as seen from a direction of a flow passage for a second fluid. The plurality heat exchange units includes a heat exchange unit having, on the projection plane, a height varying portion varying a height of a flow passage for a first fluid; and a heat exchange unit having, on the projection plane, a planar portion making the height of the flow passage for the first fluid substantially constant.

What is claimed is: 
     
         1 . A plate-type heat exchanger comprising a plurality of heat exchange units stacked on each other,
 wherein each heat exchange unit is configured to exchange heat between a first fluid flowing inside the heat exchange unit and a second fluid flowing outside the heat exchange unit,   each heat exchange unit has a plurality of through holes allowing the second fluid to flow outside the heat exchange units in a direction intersecting a flow passage plane of the first fluid flowing inside the heat exchange units,   adjacent heat exchange units are disposed in such a manner that a projection plane of the through hole in one heat exchange unit does not overlap the through hole in another heat exchange unit as seen from a direction of a flow passage for the second fluid,   the plurality of heat exchange units includes: a height varying portion-equipped heat exchange unit (P) having, on the projection plane, a height varying portion varying a height of a flow passage for the first fluid; and a planar portion-equipped heat exchange unit (Q) having, on the projection plane, a planar portion making the height of the flow passage for the first fluid substantially constant, and   at least a second heat exchange unit that is adjacent to and located on a downstream side of a most upstream heat exchange unit located on a most upstream side of the flow passage for the second fluid, includes the planar portion-equipped heat exchange unit (Q).   
     
     
         2 . The plate-type heat exchanger according to  claim 1 ,
 wherein the most upstream heat exchange unit includes the planar portion-equipped heat exchange unit (Q).   
     
     
         3 . The plate-type heat exchanger according to  claim 1 ,
 wherein the planar portion is formed on the projection plane in a region except for a peripheral region of the planar portion-equipped heat exchange unit (Q).   
     
     
         4 . The plate-type heat exchanger according to  claim 1 ,
 wherein the second heat exchange unit and the most upstream heat exchange unit are connected in series in such a manner that the first fluid passes inside the second heat exchange unit and the most upstream heat exchange unit in this order.   
     
     
         5 . The plate-type heat exchanger according to  claim 1 ,
 wherein the through hole of the planar portion-equipped heat exchange unit (Q) has a substantially rectangular shape, and   the through hole having the substantially rectangular shape is arranged in such a manner that at least one vertex protrudes to the projection plane.