| 摘要 |
PROBLEM TO BE SOLVED: To provide a shut-off valve not opened in general use but surely closed in the event of an abnormality such as breakage accident of piping by providing a passage having an inlet provided apart from a primary inlet and an outlet communicating with a secondary outlet, and a normally opened valve connected to a piston part to open and close the inlet of the passage. SOLUTION: When a sprinkler head is opened by the occurrence of a fire, an extinguishing liquid K within a fluid chamber 45 in a shut-off valve 30 is carried to a secondary outlet 61 through a passage 63 and discharged from the sprinkler head. At this time, a pressure difference is generated between a first room 40a receiving the pressure of a spring 55 and a second room 40b receiving the pressure of the liquid chamber 45 to carry the silicon oil in the room 40a to the room 40b through an orifice 51. However, since the inflow quantity of the silicon oil is small, the shut-off valve 30 keeps the opened state. When a large quantity of silicon oil is carried by the breakage of a piping, a piston part 49 falls against a spring 71 to seat a valve element 70 on a valve seat 65, and the shut-off valve 30 is closed.
|
