| 摘要 |
1278241 Moving band filter BLAKELL INDUSTRIAL PLANT Ltd 9 Sept 1969 [9 Sept 1968] 42744/68 Heading BID A moving band filter comprises a housing divided by a horizontal plate 19, having a central aperture, bridged by a grid 21, over which a filter element mounted between two chains 23 is extended, and end apertures 19a through which the chains enter the chamber above plate 19, hoods 24 being lowered by pneumatic rams 47 to seal apertures 19a before liquid is pumped into the chamber. Chains 23 are entrained over sprockets 31 and are connected by flat links (27). Filter elements are mounted between adjacent pairs of links (27), which are located under the inner edges of hoods 24 when the hoods are lowered. The hoods and plate 19 round apertures 19a have resilient seals 25, (26). A filter cloth may be extended from a supply roll 43 across the upper run of the chains, the 'filter elements' then having a supporting function only. Connected to hoods 24 is a rectangular clamping frame 38 which clamps the element or cloth round the periphery of grid 21 when the hoods are lowered. The frame is connected to the top of the chamber by pervious and flexible curtain 39. When liquid is pumped in through valve 28, some filters down through the cloth or element and some outwards through curtain 39, thereafter exerting additional sealing pressure on hoods 24. When the cloth or element clogs, the rise in pressure causes valve 28 to close and valve 46 opens to admit compressed air to force remaining liquid through the cloth. Escape of this air causes the hoods to be raised, valve 46 to be closed and the drive motor (37) to advance a new element and possibly a new section of cloth, carrying the old element, cloth and solids out of the chamber. |
