| 摘要 |
908,072. Automatic control of filters. PONSAR, Y-M. Dec. 29, 1959 [Dec. 31, 1958], No. 44149/59. Class 38 (4). [Also in Groups I and XVIII] Liquid level indicating apparatus comprising a U-tube filled to a predetermined level with a liquid L of negligible vapour pressure, e.g. mercury, and consisting of primary and secondary vessels V 1 , V 2 interconnected by a channel 10 and a reference pressure tube 11 (see Group XVIII) is employed for the automatic cleaning of a filtering drum 22 disposed between two liquid volumes having levels 23, 24. Pressures from pressure means 26, 28 corresponding to the liquid pressure heads P 1 , Pr above the pipes 25, 27 respectively are supplied through a pipe 15 and a reference pressure pipe 11 to the vessels V 1 , V 2 . If the filter becomes fouled, the level 23 and the corresponding pressure P 1 rise so that the level of mercury rises in the vessel V 2 to complete the electric circuit to a filter rotating motor 30 and a valve 32 controlling water jets 31. If the reference pressure Pr is maintained above atmospheric pressure, a suction device 14 may be substituted by a restricted orifice. |
