Patent ID: 7578339

Claim:
A heat exchanger including plate fins and tubes comprising: a plurality of fins stacked at respective intervals; and a plurality of heat exchanger tubes penetrating each of said fins in a fin-stacking direction, said heat exchanger exchanging heat between a first fluid flowing inside said heat exchanger tubes and a second fluid flowing outside said heat exchanger tubes, wherein each of said fins includes a main body that is substantially planar and a plurality of cut-raised portions extending from said main body and disposed at an upstream side of flow of the second fluid with respect to said heat exchanger tubes, each of said cut-raised portions corresponds to a respective heat exchanger tube and includes first and second opposed side ends connected to the main body of said fin, the first side end is nearer to the corresponding heat exchanger tube than is the second side end, the first side end is longer than the second side end, and the first side end is disposed at a downstream side of the flow of the second fluid, facing the corresponding heat exchanger tube, said cut-raised portions are disposed only within one of a plurality of regions of said fin, and each of said regions is centered about a respective heat exchanger tube and satisfies Ws= (1−φ) Dp+φD 1.0≧φ>0.5, Ws is the width of each of said regions corresponding to respective heat exchanger tubes in a column direction that extends parallel to an edge of each of said fins, D is the outer diameter of each of said heat exchanger tubes, Dp is the pitch of said heat exchanger tubes in the column direction, no cut-raised portion is present in an area of said fin centered, in the column direction, between adjacent pairs of said heat exchanger tubes and having a width Wf, in the column direction, satisfying Wf=φ(Dp−D), and Wf+Ws=Dp; each of said cut-raised portions includes first and second opposite edges respectively disposed at the upstream and downstream sides of the flow of the second fluid, and each of said first and second edges extends obliquely relative to the column direction.