Evertable drum centrifuge filter

An evertable drum centrifuge comprising:

• a housing extending along an axis and defining a back filtrate compartment and a front solids compartment spaced from the back filtrate compartment;
• a filter drum rotatable in the housing about the axis and having
• a generally cylindrical and perforate outer wall centered on the axis, axially fixed in the filtrate compartment, and having an axially forwardly open front end,
• an end wall extending transverse to the axis and displaceable axially between a closed position fitting in the outer-wall front end to form a closed interior therewith and an open position spaced axially forward of the outer wall and lying in the solids compartment, the end wall being formed at the axis with a central fill opening,
• extension structure fixed on the end wall and having an annular rim spaced axially backward from the end wall, and
• an annular liner of a flexible foraminous filter medium having a front edge attached to the outer-wall front end and a back edge attached to the extension-structure rim;
• actuating means for axially displacing the end wall and extension structure between the closed and open positions and thereby displacing the liner from a normal position inside the drum and extending backward from the outer-wall front end to the rim to an everted position substantially outside the drum and extending forward in the solids compartment from the outer-wall front end to the rim;
• a fill tube extending along the axis and having a back end;
• a fill head axially nondisplaceable on the fill-tube back end, complementarily engageable in the fill opening, and having an annular seal engageable with the fill tube;
• bearing means supporting the fill head on the fill tube for rotation thereon about the axis;
• guide means supporting the fill tube on the housing for movement axially thereof so that, when the end wall moves axially with the fill head engaged in the fill opening, the fill tube moves axially jointly with the end wall;
• and
• means for supplying a suspension through the fill tube and fill opening in the closed position of the end wall and normal position of the fill tube to the interior of the drum.