Filter device and filtration device

A filter apparatus comprising a filter device and a tank,

• wherein the filter device comprises:
• a first filtration unit that protrudes from an upper surface of the tank toward the inside of the tank;
• and
• a second filtration unit provided below the first filtration unit and having a substantially cylindrical shape,
• wherein the first filtration unit includes:
• a filter case that is provided with a plurality of opening portions in a side surface and has a bottomed substantially cylindrical shape;
• a lid member that covers an opening end of an upper portion of the filter case;
• a filter element that is provided inside the filter case and has a substantially cylindrical shape;
• and
• an inflow portion comprising a through hole at a side wall of the filter case, and
• wherein:
• the through hole is provided between a bottom surface of the filter case and the filter element in a height direction;
• and
• the lid member is detachably provided on the filter case;
• the filter element is detachably provided on the filter case via the opening end;
• the filter element includes a filtration material that has a substantially cylindrical shape, and an inner tube that has substantially the same height as that of the filtration material, is provided inside the filtration material, and has a substantially cylindrical shape;
• a circumferential side surface of the inner tube includes a first region and a second region;
• openings are formed over the first region such that the fluid is allowed to pass through a side wall of the inner tube, and no openings are formed on the second region;
• and
• the second region is provided below the first region to include a lower end of the inner tube.