Water transmission device and washing machine including the same

A washing machine comprising:

• a water transmission device configured to discharge water in a washing tub, the water transmission device including:
• a filter case disposed under the washing tub, the filter case accommodating a filter, and the filter case accepting the water from the washing tub;
• a pump case connected to the filter case, the pump case accommodating an impeller, the impeller configured to suction the water in the filter case and discharge;
• a motor configured to rotate the impeller;
• a coupling part separating the pump case from the filter case;
• a suction hole formed through the coupling part and communicating a side portion of the pump case facing a center of the impeller with a side portion of the filter case;
• an outlet opened downward from a lowest end inside the pump case, the outlet communicating with a water discharge pipeline;
• and
• a communicating path provided under the suction hole, the communicating path communicating a lower region inside the filter case with the outlet and including a slit vertically cut downward through the coupling part to extend from a lower end of the suction hole.