Cooling device and its cooling method

A cooling device comprising a thermal insulating box, a cooling coil part of a cooling coil disposed on at least one inner wall of the thermal insulating box, a fan arranged in front of the cooling coil part, and a cooling chamber as a space in front of the fan, where the fan discharges air into the cooling chamber to flow therein, wherein

• dry cooling air in the cooling coil part is sucked from a rear side of the fans and discharged into the cooling chamber;
• an air volume corresponding to a volume of sucked air passed through the cooling coil part is fed from the cooling chamber to the cooling coil part through areas not occupied by the cooling fan;
• a speed at which the airflow is fed is set so as to permit vapor generated in the cooling chamber to solidify before the vapor is brought into contact with the cooling coil;
• further comprising a partition to divide the thermal insulating box into a cooling space and an inner wall side space outside of the cooling space, and also a ventilating hole to pass air between the cooling space and the inner wall side space, wherein
• the cooling coil is arranged with a rear side facing the wall side space, adjacent to the wall, and a front side is combined with an inner periphery of an opening formed at the partition;
• the cooling fan is arranged in front of the cooling coil and set to rotate to discharge air behind the fan directly forward;
• further comprising a conveyor to convey a material to be cooled in the cooling space, and the cooling fan is adjacent to the conveyor;
• further comprising a rotating drum disposed in the cooling space and a belt-driving attached spirally to the rotating drum, and the conveyer circulates while moving spirally on the belt-driving plate by a rotation of the rotation drum.

A cooling method using a cooling device comprising a thermal insulating box, a cooling coil part of a cooling coil disposed on at least one inner wall of the thermal insulating box, a fan arranged in front of the cooling coil part, and a cooling chamber as a space in front of the fan, where the fan discharges air into the cooling chamber to flow therein and most of the airflow is discharged again by the fan without being returned into the cooling coil part, wherein

• the flowing air discharged again into the cooling chamber and the flowing air sucked from the cooling coil are joined before being discharged into the cooling chamber;
• an air volume corresponding to a volume of sucked air passed through the cooling coil part is fed from the cooling chamber to the cooling coil part through areas not occupied by the cooling fan;
• and
• the speed at which the air volume is fed is set so as to permit vapor generated in the cooling chamber to solidify before the vapor is brought into contact with the cooling coil.