Refrigerator

1. A refrigerator comprising:

an evaporator;

a main body including an inner case, an outer case, and an insulator foamed between the inner case and the outer case; and

a cool air circulation unit having an inner flow passage to supply cool air heat-exchanged in the evaporator to a storage compartment inside the inner case and discharge air from the storage compartment to the evaporator,

wherein the inner flow passage in the cool air circulation unit is positioned inside and outside the inner case,

wherein the cool air circulation unit includes an intermediate partition duct which divides the storage compartment and an evaporator cover which receives the evaporator, and the intermediate partition duct and the evaporator cover are coupled to each other.

2. The refrigerator according to claim 1 , wherein:

the cool air circulation unit further includes an intermediate partition positioned below the intermediate partition duct and inside the inner case, and the evaporator cover is connected to the intermediate partition below the intermediate partition and positioned inside the inner case.

3. The refrigerator according to claim 2 , wherein:

the intermediate partition duct includes an inflow passage to receive the cool air from the evaporator cover, a chamber connected to the inflow passage and receiving the cool air, and an outflow passage connected to the chamber and supplying the cool air to the storage compartment.

4. The refrigerator according to claim 3 , wherein:

the intermediate partition duct further includes a chamber cover to cover the chamber, and

the chamber changes the traveling direction of the cool air, which has been supplied from the inflow passage, to the outflow passage.

5. The refrigerator according to claim 4 , wherein:

a traveling direction of the cool air is changed by at least one of the chamber, the chamber cover, and the outflow passage.

6. The refrigerator according to claim 3 , wherein:

a cross-sectional area of an outlet of the inflow passage connected to the chamber is different from the cross-sectional area of an inlet of the outflow passage.

7. The refrigerator according to claim 2 , wherein:

the cool air starts to flow from the inner case along the inner flow passage of the cool air circulation unit, flows outside the inner case, and is finally supplied to the storage chamber of the inner case.

8. The refrigerator according to claim 3 , wherein:

the inflow passage and the outflow passage provided inside the intermediate partition duct are positioned outside the inner case.

9. The refrigerator according to claim 2 , wherein:

a return flow passage to discharge the cool air in the storage compartment is provided inside the intermediate partition.

10. The refrigerator according to claim 9 , wherein:

an inlet of the return flow passage is positioned on a surface of the intermediate partition facing the intermediate partition duct.

11. The refrigerator according to claim 9 , wherein:

the cross-sectional area of the inlet of the return flow passage is different from the cross-sectional area of an outlet of the outflow passage of the intermediate partition duct.

12. The refrigerator according to claim 9 , wherein:

a portion of the intermediate partition is in contact with an inner surface corresponding to an outer surface of the inner case in contact with the intermediate partition duct.

13. The refrigerator according to claim 2 , wherein:

the evaporator cover includes a second return flow passage therein to discharge the cool air discharged from a first return flow passage of the intermediate partition to the evaporator.

14. The refrigerator according to claim 13 , wherein:

the evaporator cover further includes a fan, and

the cool air circulates through the inner flow passage of the cool air circulation unit by the fan.

15. The refrigerator according to claim 13 , wherein:

a number of the second return flow passages is larger than a number of inflow passages of the evaporator cover.