Patent ID: 8613307
Filing Date: 2013-12-24
Classification: F28F

Abstract:
1. A finned tube heat exchanger comprising: a plurality of heat-transfer fins disposed along an airflow direction; and a plurality of heat-transfer tubes inserted into the heat-transfer fins and arranged in a direction substantially orthogonal to the airflow direction and the heat-transfer tubes being arranged with respect to each other in a vertical direction, a first axis extending in a first direction and being perpendicular to and passing through longitudinal center axes of the heat transfer tubes, the longitudinal center axes being parallel to a second vertical direction, and the airflow direction being parallel to a third direction that is perpendicular to the first and second directions, a plurality of annular collar parts protruding to one side in a plate thickness direction of each of the heat-transfer fins, with each of the heat-transfer tubes being in close contact with an inside surface of one of the annular collar parts protruding from each of the heat transfer fins, each of the heat transfer fins including each of the first set of cut-and-raised parts and the second set of cut-and-raised parts being formed by cut-and-raise machining, the first set of cut-and-raised parts and the second set of cut-and-raised parts being connected by first and second straight lines, respectively, that are sloped relative to the airflow direction as viewed along the second direction in order to guide airflow in the vicinity of the heat-transfer tubes to the rearward sides of the heat-transfer tubes in the airflow direction, the first straight line and the first set of cut-and-raised parts being parallel as viewed along the second direction, and the second straight line and the second set of cut-and-raised parts being parallel as viewed along the second direction, the first and second sets of cut-and-raised parts being disposed between a pair of heat transfer tubes that are directly adjacent to each other, the directly adjacent heat transfer tubes being aligned with each other as viewed along a direction parallel to the first axis, the first set of cut-and-raised parts being aligned with each other along the first straight line as viewed along the second direction, and the second set of cut-and-raised parts being aligned with each other along the second straight line as viewed along the second direction, the first and second sets of cut-and-raised parts disposed between the directly adjacent heat transfer tubes being at least partially aligned with the directly adjacent heat transfer tubes as viewed along the first direction, among the first set of cut-and-raised parts at least one first cut-and-raised part in a region nearest to each of the heat-transfer tubes being formed by cut-and-raise machining from the top toward the bottom, and at least one slit being formed between the at least one first cut-and-raised part and each heat-transfer tube, and each of heat transfer fins further including a plurality of concavities with each of the concavities formed by concaving in a direction opposite from a direction in which each of the collar parts protrudes on a periphery of one of the heat-transfer tubes at least partially below a horizontal plane that passes through a center axis of the heat-transfer tubes.