Filter assembly with locking cover

A filter assembly comprising:

• a tank having a cylindrical sidewall, the cylindrical sidewall defining an outer surface and an inner surface, a base for closing a bottom end of the cylindrical sidewall, wherein an upper end of the cylindrical wall is open, and a plurality of pins extending radially outwardly from the outer surface of the cylindrical wall proximate the upper end;
• a cover for closing the open top of the cylindrical wall, the cover having a top wall and a rim extending downwardly from an outer periphery of the top wall, wherein the rim defines an inner surface including a plurality of bayonet slots that respectively receive the plurality of pins on the outer surface of the cylindrical wall to lock the cover to the upper end of the cylindrical wall;
• purification media disposed in a porous filter bag, the filter bag being positioned in and sealingly engaging the inner surface of cylindrical wall of the tank;
• and
• a pivot lever located above the top wall of the cover, the pivot lever having a first end and a second end, the second end of the pivot lever having a locking arm that extends downwardly through a vertical opening in the top cover and into a horizontal portion of one of the bayonet slots, the pivot lever having a horizontal pivot pin located between the first and second ends, wherein the pivot pin is rotatably connected to the top wall of the cover via a mounting member to permit the pivot lever to pivot about a horizontal pivot axis, wherein the locking arm can be moved vertically upward out of the bayonet slot when the first end of the pivot lever is moved to a lower position thereby permitting the cover to be rotated and removed from the top end of the cylindrical wall, and wherein the locking arm can be moved vertically downward into the bayonet slot when the first end of the pivot lever moves to an upper position to retain the pin in the horizontal portion of the bayonet slot thereby locking the cover to the top end of the cylindrical wall.