1.  Field of the Invention
The present invention relates to a condensation type dryer and, more particularly, to a condensation type dryer that has an enlarged contact area between cooling water and airflow in a circulation tube to enhance drying efficiency. 
2.  Description of the Related Art
Generally, a drum washing machine washes, dehydrates, and dries laundry through a washing cycle, a spinning cycle, and a drying cycle. 
FIG.  1 is a sectional view of a conventional drum washing machine. 
Referring to FIG.  1, a drum washing machine 10 includes a cabinet 11 having an opening, a tub 13 disposed inside the cabinet 11 to receive wash water, and a drum 15 rotatably disposed inside the tub 13 and receiving laundry.  The tub 13 is provided with a drive unit 17, which is connected to the drum 15 to rotate the drum 15. 
A water supply device 18 is connected to a water supply source outside the cabinet 11 to supply wash water to the tub 13.  A drainage device 19 communicates with the tub 13 to discharge the wash water from the tub 13 to the outside. 
A dryer 20 separates moisture from air circulating inside and outside the tub 13 and changes the air into a high temperature/dry state during a drying cycle.  The dryer 20 includes a circulation tube 22 extending from a lower end of the tub 13 to the opening, a blowing fan 24 provided to the circulation tube 22 to generate an airflow, a heater 26 provided to the circulation tube 22 to heat air introduced into the tub 13 by the blowing fan 24, and a water supply tube 28 communicating with the circulation tube 22 and spraying cooling water to air discharged outside the tub 13 to collect moisture from the air. 
When the drying cycle is started, air inside the tub 13 is circulated along the circulation tube 22 by the blowing fan 24.  Here, the air circulating in the circulation tube 22 is heated into a high temperature/dry state by the heater 26 and is then supplied into the tub 13.  Then, the heated air absorbs moisture from the laundry inside the tub 13 and is discharged outside the tub 13.  The discharged air contacts the cooling water sprayed from the water supply tube 28 while circulating along the circulation tube 22, so that moisture in the air is condensed and separated from the air.  While repeating such operation, moisture remaining in the laundry can be discharged outside the tub 13. 
Since the dryer of the conventional washing machine has a narrow contact area between air circulating in the circulation tube and cooling water supplied into the circulation tube, the condensation process is inefficient and the drying operation of the dryer must be performed for a long time.  Further, during the drying operation of the dryer, some of the cooling water supplied into the circulation tube tends to flow into a blowing fan, thereby causing malfunction of the blowing fan. 
Therefore, there is a need to solve such problems.