| 摘要 |
A self-cleaning filtration device comprising a casing; a device inlet and a device outlet formed integrally with said casing; a cylindrical filter structure mounted in said casing and defining an inner zone in communication with said device inlet, and also defining with the adjacent walls of the casing an outer zone in communication with said device outlet whereby all flow from said device inlet to said device outlet passes through said filter structure, said structure including an axial stack of annular support elements, each support element comprising a flange portion and an inwardly located axially directed skirt portion, and a sleeve-like filter element surrounding said axial stack and bearing against the outermost edges of said flange portions, at least one plunger body reciprocatably displaceable in said filter structure and including a pair of axially spaced apart sealing rings of such axial extent and respective axial separation as to ensure that at all times sealing contact is maintained between said rings and a pair of successive skirt portions and so as to define with each such successive pair of skirt portions, a backflow chamber substantially sealed from said inner zone; communication means associated with said plunger element for rendering said chamber in communication with a backflow outlet so as to allow for backflow from said outer zone through the filtering structure via said chamber to the backflow outlet and displacing means for reciprocatably displacing said plunger body in said structure. |
