Patent ID: 8925625
Filing Date: 2015-01-06
Classification: F28D,F28F

Abstract:
1. A heat exchanger having a flat tube made of a metal plate that has an overlapped curved portion on an end in a cross section, wherein the flat tube comprises: a first planar wall and a second planar wall defining a thickness of the flat tube, a center plane of the flat tube being defined midway between the first and second planar walls, the center plane extending in a direction parallel to the first and second planar walls; an inner rim placed inside of an outer rim; the outer rim placed on an outside of the inner rim; a small radius region formed on the inner rim; a large radius region formed on the inner rim having a larger radius than the small radius region; wherein an end face of the outer rim is placed on the large radius region at an approximate mid-point of the large radius region of the inner rim; a thickness of the outer rim is equal to a thickness of the inner rim at an intersection with the center plane; a thickness of the outer rim becoming thinner from a first point located between the intersection with the center plane and an end face of the outer rim to a second point located at the end face of the outer rim; and the first point on the outer rim and an end face of the inner rim are located on opposite sides of the center plane.