| 摘要 |
1,204,992. Valve-controlled filters. PUREX CORP. Ltd. 28 Feb., 1969 [10 Sept., 1968], No. 10998/69. Heading BID. [Also in Division F2] During normal filtration flow, water (e.g. from a swimming pool) enters port 29, passes through conduit 51 of a plug valve and hence through a filter element 11; filtrate collected by conduits 22 enters a manifold chamber 20 and is discharged at 28. To backwash, a handle 46 is rotated to put conduit 51 in contact with a wasteport 30 and to cause the plug to block outlet 28; hence water issues from conduits 22, backwashes the filter, and is discharged via conduit 51 and port 30. The valve unit 12 is formed in upper and lower halves which clamp housing 10 between them. Filter element 11 may be a sand bed. |
