To provide a water spray system for a tunnel which is capable of performing advance-notice water discharge by a simple structure of the system and at a low cost.
A first port P1 of a three-way valve 50 disposed on a secondary side of an automatic valve 30 is connected to a water spray head 12, and a second port P2 of the three-way selector valve 50 is connected to an advance-notice water discharge head 16. When the automatic valve 30 is remotely actuated, the three-way valve 50 is connected to the second port P2 and a small volume of water is discharged from the advance-notice water discharge head 16 as the advance-notice water discharge. After the elapse of a prescribed time period, the three-way valve 50 is switched to the first port P1, and the advance-notice water discharge from the advance-notice water discharge head 16 is stopped and at the same time, main water discharge is started from the water spray head 12.
IBARAKI HIROSHI
ISHIDA HIROSHI
IWATA TERUO
| JP2002355324A | 2002-12-10 |