| 摘要 |
<p>PROBLEM TO BE SOLVED: To cut off a passage at a fast speed by pressure air when the earthquake of a specified level or higher is sensed, and to automatically replenish a reservoir tank with pressure air when the pressure of pressure air in the reservoir tank is reduced. SOLUTION: When the earth quake of specified intensity or higher is sensed in the open state of a passage opening/closing valve 10, pressure air in a reservoir tank 40 is sent to an emergency cut-off air cylinder 20 to close the passage opening/closing valve 10, and when the pressure of pressure air in the reservoir tank 40 is reduced to a specified value or lower, a piston 21 is reciprocated by a motor 15 for driving the passage opening/closing valve to generate pressure air, and this pressure air is sent to the reservoir tank 40.</p> |
