| 摘要 |
PURPOSE:To prevent the failure of operations due to rusting and the occurrence of maloperation by a method in which a flexible bag dam having a rising and falling mechanism is provided with a siphon tube in such a way as to enable a preparation for automatic rising of the dam to be made simply. CONSTITUTION:An air blower to send air under pressure to a flexible bag dam 1 is provided through an air supply tube a check valve 6 and a manual falling valve 7. An operating pit is led to flowing water A on the upstream side through a notched weir 10 and also to flowing water B on the downstream side through siphon tube 11 and a siphon breaker 18. An excess air discharge tube 12 is led to the notched weir 10 at its lower part and also to the air supply tube 8 through a valve 13 at its upper part. A water-sealing tube 15 is also led to the lower end of a U-shaped exhaust tube 14 at its lower part and also to a negative pressure tube 16 leading to the siphone tube 11 at its upper part. The lower part of the tube 15 is also provided with a U-shaped communication tube 17. |
