Patent ID: 6861003

Claim:
Filtering apparatus, comprising (a) a vessel having first and second compartments divided by a partition and having a fluid inlet for admitting fluid to be filtered into the first compartment and a fluid outlet for discharging filtered fluid from the second compartment, (b) at least one filter element, comprising (i) a pervious tube extending through the partition having a hollow core, one end of the tube being closed and the other open, the open end being in communication with the second compartment, the tube being located substantially within the first compartment, and (ii) a plurality of annular filter elements stacked coaxially along the portion of the tube within the first compartment and retained thereon under compression by a retainer at each end of the tube, (c) a compression regulator linked to at least one retainer and responsive to pressure of fluid admitted into the first compartment, the retainer being movable along an axis of the tube in a direction to further compress the stacked filter elements and the compression regulator controlling the movement of the retainer when the pressure of fluid admitted into the first compartment increases beyond a preselected pressure.