Heat exchanger and refrigeration cycle device

Abstract

A heat exchanger includes: a heat exchange portion in which a plurality of heat transfer tubes, in which refrigerant flows, are arranged in a height direction and grouped into, in order from an upper side in the height direction, a main, first auxiliary and second auxiliary heat exchange portion and configured to, when the heat exchanger serves as a condenser, allow the refrigerant to flow through the heat exchanger in order of the main heat exchange portion of the airflow downstream side row, the main heat exchange portion of the airflow upstream side row, the first auxiliary heat exchange portion of the airflow upstream side row, the first auxiliary heat exchange portion of the airflow downstream side row, the second auxiliary heat exchange portion of the airflow downstream side row, and the second auxiliary heat exchange portion of the airflow upstream side row, and flow out of the heat exchanger.

1 . A heat exchanger comprising:
 a heat exchange portion in which a plurality of heat transfer tubes, in which refrigerant flows, are arranged in a height direction, the plurality of heat transfer tubes being configured to exchange heat between the refrigerant and air;   a turn-back portion to which one end of each of the plurality of heat transfer tube is connected and which is configured to allow the refrigerant to flow between two rows of heat exchange portions arranged in an airflow direction,   one of the two rows of heat exchange portions being the heat exchange portion and arranged on an airflow upstream side,   an other of the two rows of heat exchange portions being the heat exchange portion and arranged on an airflow downstream side; and   a plurality of distribution merge portions to each of which the other end of the heat transfer tube of the heat exchange portion of each row is connected, and which is configured to distribute the refrigerant to the heat transfer tube or merge refrigerant flows from the heat exchange portions,   the plurality of heat transfer tubes of the heat exchange portion being grouped into, in order from an upper side in the height direction,
 a main heat exchange portion, 
 a first auxiliary heat exchange portion having fewer number of the heat transfer tubes than those of the main heat exchange portion, and 
 a second auxiliary heat exchange portion having fewer number of the heat transfer tubes than those of the first auxiliary heat exchange portion, 
   and being configured to, when the heat exchanger serves as a condenser, allow the refrigerant to flow through the heat exchanger in order of the main heat exchange portion of the airflow downstream side row,
 the main heat exchange portion of the airflow upstream side row, 
 the first auxiliary heat exchange portion of the airflow upstream side row, 
 the first auxiliary heat exchange portion of the airflow downstream side row, 
 the second auxiliary heat exchange portion of the airflow downstream side row, and 
 the second auxiliary heat exchange portion of the airflow upstream side row, and allow the refrigerant to flow out of the heat exchanger, 
   wherein in the main heat exchange portion, the heat transfer tubes are further divided into a plurality of subgroups by distribution paths of the refrigerant from the distribution merge portions.   
     
     
         2 . The heat exchanger of  claim 1 , wherein the heat exchange portion of the airflow upstream side row, and the heat exchange portion of the airflow downstream side row have equal number of the heat transfer tubes. 
     
     
         3 . (canceled) 
     
     
         4 . The heat exchanger of  claim 1 , wherein the main heat exchange portion has fewer number of the heat transfer tubes in the subgroups through which a large amount of the air passes than those in other subgroups. 
     
     
         5 . The heat exchanger of  claim 1 , wherein the turn-back portion connects the heat transfer tubes of the main heat exchange portion in the heat exchange portion of the airflow upstream side row, and the heat transfer tubes of the main heat exchange portion in the heat exchange portion of the airflow downstream side row to each other on a one-to-one basis. 
     
     
         6 . The heat exchanger of  claim 1 , wherein the distribution merge portions include a layered distributor of a plurality of plate-like parts stacked on one another. 
     
     
         7 . The heat exchanger of  claim 1 , wherein each of the heat transfer tubes is a flat heat transfer tube having a flat shape in cross-section, and having flow passages therein through which the refrigerant flows. 
     
     
         8 . A refrigeration cycle device comprising the heat exchanger of  claim 1  to serve at least as a condenser. 
     
     
         9 . The refrigeration cycle device of  claim 8 , wherein
 the heat transfer tubes of the heat exchange portion in the heat exchanger have a relationship expressed as
 number of the heat transfer tubes of the main heat exchange portion>number of the heat transfer tubes of the first auxiliary heat exchange portion>number of the heat transfer tubes of the second auxiliary heat exchange portion, and 
   when the heat exchanger serves as an evaporator, a temperature of refrigerant flowing into the heat exchanger from the second auxiliary heat exchange portion of the airflow upstream side row is higher than a temperature of the air flowing into the heat exchange portion.   
     
     
         10 . The refrigeration cycle device of  claim 7 , comprising an air-sending device including a fan and oriented with a rotational shaft of the fan extending in a same direction as a direction in which air passes through the heat exchange portion, the air-sending device being configured to allow the air to pass through the heat exchange portion, wherein
 number of the heat transfer tubes in the subgroup nearest in distance from a rotation center of the fan is fewer than those in the other subgroups.   
     
     
         11 . The heat exchanger of  claim 2 , wherein the main heat exchange portion has fewer number of the heat transfer tubes in the subgroups through which a large amount of the air passes than those in other subgroups. 
     
     
         12 . The heat exchanger of  claim 2 , wherein the turn-back portion connects the heat transfer tubes of the main heat exchange portion in the heat exchange portion of the airflow upstream side row, and the heat transfer tubes of the main heat exchange portion in the heat exchange portion of the airflow downstream side row to each other on a one-to-one basis. 
     
     
         13 . The heat exchanger of  claim 4 , wherein the turn-back portion connects the heat transfer tubes of the main heat exchange portion in the heat exchange portion of the airflow upstream side row, and the heat transfer tubes of the main heat exchange portion in the heat exchange portion of the airflow downstream side row to each other on a one-to-one basis. 
     
     
         14 . The heat exchanger of  claim 2 , wherein the distribution merge portions include a layered distributor of a plurality of plate-like parts stacked on one another. 
     
     
         15 . The heat exchanger of  claim 4 , wherein the distribution merge portions include a layered distributor of a plurality of plate-like parts stacked on one another. 
     
     
         16 . The heat exchanger of  claim 5 , wherein the distribution merge portions include a layered distributor of a plurality of plate-like parts stacked on one another.