US Patent 10082328 Refrigerator

There is disclosed a refrigerator including an inner case that defines an exterior appearance of a storage space, with a communication hole formed therein, an outer case spaced apart a predetermined distance from the inner case, with a communication formed at a position corresponding to the communication hole of the inner case, a vacuum space provided between the inner case and the outer case, with being maintained vacuum, to insulate the inner case from the outer case, and a connection pipe passing through the vacuum space, to connect the communication hole of the inner case and the communication hole of the outer case with each other.