Evaporator for home refrigerator

摘要

A tube and fin-type evaporator is provided for a refrigerator having trapezoidally shaped fins with the wider portion of the fins disposed upstream in the cooling air flow path through the evaporator. The refrigerant tube passes through at least two rows of openings in these fins, and those openings are staggered and of different length to enhance turbulence and reduce tube shielding within the cooling air flow. Projections (dimples) on the fins adjacent the downstream side of each opening are provided to reduce dead air space downstream from the tube. Further, the openings are provided with collars to increase heat transfer between the fins and the tube. These projections and collars also serve to increase rigidity of the fins. The present invention enables the use of relatively small diameter, thin walled refrigerant tubes within the evaporator. Also, the tubes can be hydraulically expanded within the fins to enhance fin to tube contact and decrease heat transfer resistance.