| 摘要 |
PURPOSE:To suppress the adherence and growth of frost on the surfaces of fins and to prolong the time required until spaces between fins are blocked by frost thereby to improve comfort by making the heights of the upstream parts of the air current of fin collars in the first row from the upstream side of the air current, lower than the heights of other parts. CONSTITUTION:Each of heat transfer pipes 2 are inserted into each of fin collars 3 formed at a predetermined interval in a large number of fins 1a disposed in parallel. Further, the height of each of air current upstream side portions 3a in the fin collars 3 in the first row from the air current upstream side is made lower than than the heights of other portions 3b. As a result, the contact thermal resistance between the air current upstream side portion 3a and the heat transfer pipe becomes large. The air current upstream side fin ends 4a in the direction shown by arrows and the fin ends 4b between two adjacent heat transfer pipes, have substantially the same temperature difference with the flow-in air. Consequently, when the finned heat exchanger is used as an outdoor heat exchanger of an air conditioner, and the air conditioner is operated in a space heating mode, the thickness of frost 5 adhering to and growing on the fin ends 4 becomes uniform and the time required for blocking the spaces between the fins 6 due to frost 5 is prolonged. |
