Filter apparatus with sealing collector and flow control element

Abstract

An improved pressurized filter apparatus, which filters fluid axially through filter elements formed with wound layers of tissue, includes at least one fluid collector with at least one passageway for filtered fluid to flow from the adjacent filter elements inwardly into the centrally located flow path to the filter exit port. The passageways are formed by upraised ridges which space the filter element exit ends from the substantially flat portion of the collector. Annular ring portions project axially from the flat portion of the collector into the adjacent filter element exit ends to form a first seal which separates unfiltered fluid from filtered fluid. A rigid outer retention ring projects axially from the outer perimeter of the collector flat portion, and includes one inside surface for each adjacent filter element which abuts against the periphery of the adjacent filter element to form a second seal which further ensures separation of unfiltered fluid from filtered fluid. When filter elements are arranged so that the intake ends of two filter elements face each other, the filter apparatus also may include a directional flow control element which forms a third seal with each of the two filter element intake ends to prevent the unfiltered fluid from bypassing the filter elements by leaking into the centrally located flow path. The pressurized axially fluid filter apparatus also may include at least one substantially non-expandable sheath, each of which surrounds one collector and encloses the peripheries of the adjacent filter elements to thereby limit expansion of the filter elements due to water adsorption.