| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an opening-closing device for use in a channel of sewerage etc., which rapidly opens a valve body. <P>SOLUTION: This opening-closing device 1 includes: a gate 10 which receives a flow of sewage water W and which can be brought down in the downstream direction of the flow; a fall prevention portion 20b which prevents the fall of the gate 10 by supporting the gate 10; a support release portion 22b for releasing the support of the gate 10 by the fall prevention portion 20b; a first float 18 which is arranged on the upstream side with respect to the gate 10, and which is smaller in specific gravity than the sewage water W; a surfacing prevention portion 44 for preventing the surfacing of the first float 18; a second float 16 which is arranged on the upstream side with respect to the gate 10, which is arranged above the first float 18, and which is smaller in specific gravity than a fluid; and a surfacing prevention release portion 42 which releases the prevention of the surfacing of the first float 18 by the surfacing prevention portion 44, along with the surfacing of the second float 16. Additionally, the support release portion 22b operates along with the surfacing of the first float 18. <P>COPYRIGHT: (C)2010,JPO&INPIT |
