Heat exchanger and air conditioner

Abstract

A heat exchanger includes: a heat transfer tube allowing a refrigerant to flow; and a fin having through holes that are aligned in columns in a second direction crossing a first direction in which air flows. The through holes include: first through holes each penetrated by the heat transfer tube in a thickness direction of the fin; and second through holes not penetrated by the heat transfer tube. The fin includes: a first region having the first through holes; and a second region having the second through holes. One or both ends of the second region in the first direction are adjacent to the first region. Both ends of the second region in the second direction are adjacent to the first region.

What is claimed is: 
     
         1 . A heat exchanger comprising:
 a heat transfer tube allowing a refrigerant to flow; and   a fin having through holes that are aligned in columns in a second direction crossing a first direction in which air flows, the through holes including:
 first through holes each penetrated by the heat transfer tube in a thickness direction of the fin; and 
 second through holes not penetrated by the heat transfer tube, wherein the fin comprises: 
   a first region having the first through holes; and   a second region having the second through holes,   one or both ends of the second region in the first direction are adjacent to the first region, and   both ends of the second region in the second direction are adjacent to the first region.   
     
     
         2 . The heat exchanger according to  claim 1 , wherein
 the first through holes include an outlet through hole through which the heat transfer tube penetrates and at which a refrigerant evaporated in the heat exchanger exits, and   the outlet through hole is adjacent to the first region in the first direction.   
     
     
         3 . The heat exchanger according to  claim 2 , wherein the outlet through hole is adjacent to a windward side of the first region. 
     
     
         4 . The heat exchanger according to  claim 1 , wherein the through holes in a column on a windward side of the heat exchanger are staggered with respect to the through holes in a column on a leeward side of the heat exchanger. 
     
     
         5 . The heat exchanger according to  claim 1 , wherein
 the fin comprises a narrow portion having a smaller width than an average width of the fin in the first direction, and   the first through holes include a narrow portion through hole closest to the narrow portion.   
     
     
         6 . The heat exchanger according to  claim 5 , wherein the fin is bent in the first direction at the narrow portion. 
     
     
         7 . The heat exchanger according to  claim 5 , wherein
 the first through holes include an inlet through hole through which the heat transfer tube penetrates and at which a refrigerant evaporated in the heat exchanger enters, and   the narrow portion through hole is the inlet through hole.   
     
     
         8 . The heat exchanger according to  claim 7 , wherein the narrow portion through hole is adjacent in the first direction to the second region. 
     
     
         9 . The heat exchanger according to  claim 1 , wherein
 the first through holes include an inlet through hole through which the heat transfer tube penetrates and at which a refrigerant evaporated in the heat exchanger enters, and   the inlet through hole is disposed:
 in a region where air passing the heat exchanger has air flow speed higher than average air flow speed, and 
 in a column on a leeward side of the heat exchanger. 
   
     
     
         10 . An air conditioner comprising:
 a refrigerant circuit comprising a compressor, a heat source heat exchanger, an expansion valve, and a utilization heat exchanger connected in a mentioned order, wherein   the utilization heat exchanger comprises the heat exchanger according to  claim 1 .   
     
     
         11 . The air conditioner according to  claim 10 , further comprising a control unit configured to control an opening degree of the expansion valve such that a refrigerant that evaporates in the utilization heat exchanger and that flows out of the heat transfer tube serving has a dryness degree equal to or more than a predetermined value.