PURPOSE: To eliminate danger such that the hand of a person comes in touch with an edge tool or foreign matter is bit in the edge tool by forming a siphon part curved into a U-shape upwardly to the drain passage connecting the charge port of a sink to a disposer.

CONSTITUTION: A charge port 17 in which garbage is charged is opened to the bottom surface of a sink 2 and a disposer 3 is arranged under the sink 2. A siphon part 13 curved into a U-shape upwardly is formed to the drain passage 12 connecting the charge port 11 and the disposer 3. As a result, there is no danger such that the hand of a person comes in touch with an edge tool and foreign matter is bit in the edge tool and work can be performed safely. The offensive smell generated from the disposer is blocked by the water remaining in the drain passage and the rising of the offensive smell can be prevented.