Heat exchanger

Abstract

A fin has a U-form cutaway portion into which a flat tube is fitted and a fin collar standing inclined from an edge portion of the cutaway portion, and an opened end width W2 of the cutaway portion is formed to be larger than an outer width W1 of the flat tube. Also, the fin collar has a fin collar inclined face portion standing inclined with respect to a fin flat face from the edge portion of the cutaway portion, and a fin collar end face portion bent from an end portion of the fin collar inclined face portion and in surface contact with an outer face of the flat tube.

1 . A heat exchanger, comprising:
 a multiple of a flat tube that forms a passage of a heat conducting medium and whose cross-section is of a flat form; and   a multiple of a fin, fixed to the flat tube, whose main flat face is perpendicular to a passage direction of the flat tube, and which is disposed at intervals in the passage direction, wherein   the fin has a cutaway portion into which the flat tube is fitted and a fin collar standing erect from an edge portion of the cutaway portion,   an opened end of the cutaway portion is larger than an outer width of the flat tube,   an aperture form of the cutaway portion is U-form, one semi-circular end portion of the flat tube is fitted into a semi-circular portion forming a closed end of the cutaway portion, and   the fin collar has a fin collar inclined face portion standing inclined with respect to a fin flat face from the edge portion of the cutaway portion, and a fin collar end face portion bent from an end portion of the fin collar inclined face portion and in surface contact with an outer face of the flat tube.   
     
     
         2 . The heat exchanger according to  claim 1 , wherein
 the fin collar inclined face portion extends from two linear edge portions reaching from the opened end to the closed end of the cutaway portion, and stands erect facing the outer face of the flat tube at an angle of less than 90 degrees with respect to the fin flat face.   
     
     
         3 . The heat exchanger according to  claim 2 , wherein
 the opened end of the cutaway portion is larger than the closed end, and the two linear edge portions of the cutaway portion are parallel.   
     
     
         4 . The heat exchanger according to  claim 2 , wherein
 the opened end of the cutaway portion is larger than the closed end, and each of the two linear edge portions of the cutaway portion is positioned on a line connecting the opened end and the closed end.   
     
     
         5 . The heat exchanger according to  claim 1 , wherein
 the fin collar inclined face portion and the fin collar end face portion are both flat faces.   
     
     
         6 . The heat exchanger according to  claim 1 , wherein
 the fin collar inclined face portion is a curved face, and the fin collar end face portion is a flat face.   
     
     
         7 . The heat exchanger according to  claim 1 , wherein
 the fin has a narrow cutaway portion whose opened end is smaller than the outer width of the flat tube in addition to the cutaway portion.   
     
     
         8 . The heat exchanger according to  claim 7 , wherein
 the cutaway portion and the narrow cutaway portion are alternately disposed in an end portion of the fin.   
     
     
         9 . The heat exchanger according to  claim 2 , wherein
 the opened end of the cutaway portion is larger than the closed end, fin collars standing erect from each of the two linear edge portions of the cutaway portion are of differing forms, one of the edge portions is positioned on a line parallel to the main flat face of the flat tube, and the other of the edge portions is positioned on a line connecting the opened end and the closed end.   
     
     
         10 . The heat exchanger according to  claim 2 , wherein
 the opened end of the cutaway portion is larger than the closed end, fin collars standing erect from each of the two linear edge portions of the cutaway portion are of differing forms, one of the edge portions is positioned on a line connecting a position offset in a direction in which the cutaway portion spreads from the closed end and the opened end, and the other of the edge portions is positioned on a line connecting the opened end and the closed end.