Backwashing Fluid Discharge Apparatus and Filter Unit

A filter unit comprising:

• a filter member for removing a foreign substance from a fluid;
• a main body in which the filter member is installed;
• a filtering unit coupled to the main body for moving the fluid from an inside of the filter member to an outside of the filter member in order to remove the foreign substance from the fluid;
• a backwash unit coupled to the main body for moving the fluid from the outside of the filter member to the inside of the filter member in order to separate the foreign substance from the filter member;
• and
• a drainage device coupled to the main body so as to be located within the filter member,
• wherein the drainage device includes a plurality of inlet holes for introduction of backwash fluid, the inlet holes being configured to allow the backwash fluid, moved from the outside of the filter member to the inside of the filter member, to be discharged to the backwash unit by passing through a penetration opening formed in the main body, the inlet holes being formed so as to be located at different heights in order to enable introduction of the backwash fluid at the different heights.