Heat exchanger and air conditioner

Abstract

Disclosed herein is a heat exchanger including: a plurality of banks, each of which includes a plurality of flat tubes, arranged in an air flow direction. The refrigerants in the plurality of banks flow in parallel with each other, and each of the flat tubes in the plurality of banks has one or more bent portions which are bent in a width direction of the flat tubes such that the flat tubes of a pair of the banks adjacent to each other in the air flow direction extend along with each other.

1 . A heat exchanger, comprising:
 a plurality of flat tubes arranged parallel to each other, in each of which a plurality of refrigerant channels are formed; and fins joined to the flat tubes, the heat exchanger allowing a refrigerant flowing through each of the refrigerant channels to exchange heat with air, wherein   a plurality of banks, each of which includes two or more of the flat tubes, are arranged in an air flow direction,   the refrigerants in the plurality of banks flow in parallel with each other, and   each of the flat tubes in the plurality of banks has one or more bent portions which are bent in a width direction of the flat tubes such that the flat tubes of a pair of the banks adjacent to each other in the air flow direction extend along each other.   
     
     
         2 . The heat exchanger of  claim 1 , wherein
 each of the banks includes a principal heat exchange region provided for two or more of the flat tubes arranged side by side in an arrangement direction of the flat tubes in each bank, and an auxiliary heat exchange region provided for the flat tubes, which are smaller in number than the two or more of the flat tubes of the principal heat exchange region, and   in the plurality of banks, the refrigerants in the principal heat exchange regions adjacent to each other in the air flow direction flow in parallel with each other, and the refrigerants in the auxiliary heat exchange regions adjacent to each other in the air flow direction flow in parallel with each other.   
     
     
         3 . The heat exchanger of  claim 2 , wherein
 the refrigerant in the flat tubes in the principal heat exchange region and the refrigerant in the flat tubes in the auxiliary heat exchange region in a pair of the banks adjacent to each other in the air flow direction flow in the same direction, and   the heat exchanger further comprises: a branched gas pipe having branches communicating with one end of each of the flat tubes in the principal heat exchange region of each bank,   a branched liquid pipe having branches communicating with one end of each of the flat tubes in the auxiliary heat exchange region of each bank, the one end being adjacent to the branched gas pipe, and   a communicating pipe which allows the other end of each of the flat tubes in the principal heat exchange region of the bank to communicate with the other end of an associated one of the flat tubes in the auxiliary heat exchange region of the bank.   
     
     
         4 . The heat exchanger of  claim 1 , wherein
 the plurality of banks are configured such that when the heat exchanger functions as an evaporator, the refrigerants in the flat tubes in a pair of the banks adjacent to each other in the air flow direction flow in opposite directions.   
     
     
         5 . The heat exchanger of  claim 4 , wherein
 when the heat exchanger functions as the evaporator, superheated refrigerant regions of the flat tubes of a pair of the banks adjacent to each other in the air flow direction do not overlap with each other in the air flow direction.   
     
     
         6 . An air conditioner, comprising:
 a refrigerant circuit which includes the heat exchanger of  claim 1 , and performs a refrigeration cycle, wherein   the air conditioner is switchable between an operation in which the heat exchanger functions as an evaporator, and an operation in which the heat exchanger functions as a condenser.