| 摘要 |
PURPOSE:To perform freezing in one direction from the surface towards the bottom by air in a freezing compartment to form ice crystals while gaseous substances and impurities in water is rejected into water in the lower portion, by a method wherein a heater is closely attached on the outer wall of a water storage after the water storage and a drain port are covered with heat insulating material, and a draining unit and a drain pipe are attached to the drain port. CONSTITUTION:Covered by heat insulating material 25, a water storage 28 is barely affected by cooling effect from the periphery, and freezing progresses in one direction from top of small sections 31 in an ice making tray 30 towards bottom because the periphery of the water storage 28 is heated by a heater 39. As a result, when the freezing speed is adequately reduced, the gaseous substances dissolved in water and a various kind of impurities contained in water are rejected out from the ice crystals and discharged into ice making water in a lower portion. However, the bottoms of the small sections 31 are connected to each other through openings on the bottoms, and there is no obstacle wall that interferes the dispersion of gaseous substances and the sedimentation of impurities, so that they are discharged into water in the lower portion of the water storage 28. |
