Tube fitting, heat exchanger, and air-conditioning apparatus

Abstract

A tube fitting includes a through portion. A flat tube is connected to the first end portion of the through portion, and another tube different in cross-sectional shape from the flat tube is connected to the second end portion of the through portion. The central axis of the first end portion and the central axis of the second end portion are deviated from each other.

1 . (canceled) 
     
     
         2 . The heat exchanger of  claim 5 ,
 wherein an inner diameter D of the second end portion of the first tube fitting connected to the first flat tube in a cross-section perpendicular to the central axis with respect to an entire circumference is smaller than or equal to an inner diameter W 1  of the first end portion of the first tube fitting connected to the first flat tube in the major axis, and equal to or larger than an inner diameter W 2  of the first end portion in the minor axis.   
     
     
         3 . The heat exchanger of  claim 5 ,
 wherein   an outer circumferential surface of the row joint tube is joined to an inner circumferential surface of the second end portion of the first tube fitting connected to the first flat tube,   the through portion includes a shape transition section formed in a region between the first end portion and the second end portion, the shape transition section being configured so as to gradually translate a cross-sectional shape of the inner circumferential surface of the first end portion into a cross-sectional shape of the inner circumferential surface of the second end portion, and   a region in the inner circumferential surface of the second end portion of the first tube fitting connected to the first flat tube, where the outer circumferential surface of the row joint tube is joined is adjacent to the shape transition section.   
     
     
         4 . (canceled) 
     
     
         5 . A heat exchanger comprising:
 a first tube fitting including a through portion, to a first end portion of which a first flat tube is connected and to a second end portion of which an other tube different in cross-sectional shape from the first flat tube is connected; and   a heat exchange unit including the flat tube, at least an end portion of which is connected to the first end portion of the tube fitting, and an other flat tube located on a windward side or a leeward side of the flat tube,   wherein a central axis of the first end portion and a central axis of the second end portion of the first tube fitting connected to the first flat tube are deviated from each other,   the second end portion of the first tube fitting connected to the first flat tube and the first flat tube are connected to each other via a row joint tube, and   a distance between the central axis of the second end portion of the first tube fitting connected to the first flat tube and the central axis of the second flat tube is shorter than a distance between the central axis of the first end portion of the first tube fitting connected to the first flat tube and the central axis of the second flat tube.   
     
     
         6 . The heat exchanger of  claim 5 ,
 wherein the heat exchange unit acts as evaporator and the second flat tube is located windward of the first flat tube.   
     
     
         7 . The heat exchanger of  claim 5 ,
 wherein the heat exchange unit acts as condenser and the second flat tube is located leeward of the first flat tube.   
     
     
         8 . A heat exchanger comprising:
 a first tube fitting including a through portion, to a first end portion of which a first flat tube is connected and to a second end portion of which an other tube different in cross-sectional shape from the first flat tube is connected;   a second tube fitting including a through portion, to a first end portion of which a second flat tube is connected and to a second end portion of which an other tube different in cross-sectional shape from the second flat tube is connected;   a heat exchange unit including the first flat tube and the second flat tube, at least each of one end portions of which is connected to the corresponding first end portion of the first tube fitting and the second tube fitting, the first flat tube and the second flat tube being respectively located on a windward side and a leeward side; and   a header connected to the heat exchange unit and located on the windward side and a header connected to the heat exchange unit and located on the leeward side,   wherein the second end portion of the first tube fitting connected to the first flat tube located on the windward side and the second end portion of the second tube fitting connected to the second flat tube located on the leeward side are connected to each other via a row joint tube,   the row joint tube is located between the heat exchange unit and the header located on the windward side and the header located on the leeward side, and   the first tube fitting connected to the first flat tube and the second tube fitting connected to the second flat tube are configured such that an inner diameter D of the second end portion in a cross-section perpendicular to the central axis with respect to an entire circumference is smaller than or equal to an inner diameter W 1  of the first end portion in the major axis, and equal to or larger than an inner diameter W 2  of the first end portion in the minor axis.   
     
     
         9 . The heat exchanger of  claim 5 ,
 wherein a flow path cross-sectional area of the row joint tube is larger than a flow path cross-sectional area of the first flat tube or the second flat tube.   
     
     
         10 . A heat exchanger comprising:
 a first tube fitting including a through portion, to a first end portion of which a first flat tube is connected and to a second end portion of which an other tube different in cross-sectional shape from the first flat tube is connected;   a heat exchange unit including the first flat tube, at least an end portion of which is connected to the first end portion of the first tube fitting; and   a header including a branch flow path for delivering refrigerant in branched flows or a junction flow path for delivering a merged flow of the refrigerant, and a joint tube provided at an outlet of the branch flow path and connected to the second end portion of the first tube fitting connected to the first flat tube or a joint tube provided at an inlet of the junction flow path and connected to the second end portion of the first tube fitting connected to the first flat tube,   wherein an outer circumferential surface of the joint tube is joined to an inner circumferential surface of the second end portion of the first tube fitting connected to the first flat tube,   the through portion includes a shape transition section formed in a region between the first end portion and the second end portion, the shape transition section being configured so as to gradually translate a cross-sectional shape of the inner circumferential surface of the first end portion into a cross-sectional shape of the inner circumferential surface of the second end portion, and   a region in the inner circumferential surface of the second end portion of the first tube fitting connected to the first flat tube is joined is adjacent to the shape transition section.   
     
     
         11 . A heat exchanger comprising:
 a first tube fitting including a through portion, to a first end portion of which a first flat tube is connected and to a second end portion of which an other tube different in cross-sectional shape from the first flat tube is connected;   a heat exchange unit including the first flat tube, at least an end portion of which is connected to the first end portion of the first tube fitting; and   a header including a branch flow path for delivering refrigerant in branched flows or a junction flow path for delivering a merged flow of the refrigerant, and a joint tube provided at an outlet of the branch flow path and connected to the second end portion of the first tube fitting connected to the first flat tube or a joint tube provided at an inlet of the junction flow path and connected to the second end portion of the first tube fitting connected to the first flat tube,   wherein the first tube fitting is configured such that an inner diameter D of the second end portion connected to the first flat tube in a cross-section perpendicular to the central axis with respect to an entire circumference is smaller than or equal to an inner diameter W 1  of the first end portion in the major axis, and equal to or larger than an inner diameter W 2  of the first end portion in the minor axis.   
     
     
         12 . The heat exchanger of  claim 10 ,
 wherein a flow path cross-sectional area of the joint tube is larger than a flow path cross-sectional area of the first flat tube.   
     
     
         13 . An air-conditioning apparatus comprising the heat exchanger of  claim 5 . 
     
     
         14 . A heat exchanger comprising:
 a first tube fitting including a through portion, to a first end portion of which a first flat tube is connected, and to a second end portion of which an other tube, different in cross-sectional shape from the first flat tube, is connected;   a second tube fitting including a through portion, to a first end portion of which a second flat tube is connected, and to a second end portion of which an other tube, different in cross-sectional shape from the second flat tube, is connected;   a heat exchange unit including the first flat tube and the second flat tube, at least each of one end portions of which is connected to the corresponding first end portion of the first tube fitting and the second tube fitting, the first flat tube and the second flat tube being respectively located on a windward side and a leeward side; and   a header connected to the heat exchange unit and located on the windward side and a header connected to the heat exchange unit and located on the leeward side,   wherein the second end portion of the first tube fitting connected to the first flat tube located on the windward side and the second end portion of the second tube fitting connected to the second flat tube located on the leeward side are connected to each other via a row joint tube,   the row joint tube is located between the heat exchange unit and the header located on the windward side and the header the leeward side,   an outer circumferential surface of the row joint tube is joined to an inner circumferential surface of the second end portion of each of the first tube fitting connected to the first flat tube and the second tube fitting connected to the second flat tube,   the through portion includes a shape transition section formed in a region between the first end portion and the second end portion, the shape transition section being configured so as to gradually translate a cross-sectional shape of the inner circumferential surface of the first end portion into a cross-sectional shape of the inner circumferential surface of the second end portion, and   a region in the inner circumferential surface of the second end portion of each of the first tube fitting connected to the first flat tube and the second tube fitting connected to the second flat tube, where the outer circumferential surface of the row joint tube is joined is adjacent to the shape transition section.