| 摘要 |
PURPOSE:To suck up air by closing a main air sucking port ordinarily used when the existence of water is detected and opening an auxiliary air sucking port which is separately provided and impervious to water. CONSTITUTION:In the intermediate of an air duct 3, an auxiliary air suction valve port 6 is opened at the side wall, and a changeover valve 7 is arranged thereat. The changeover valve 7 is fitted with a valve body 7b which opens and closes the passage of an air duct 3, and a valve body 7c which opens and closes an auxiliary air suction port 6 outside the passage, and the passage of the air duct 3 is opened and the auxiliary air suction port is closed by the valve body 7c. When water is accumulated within a vessel 24 and water infiltrates in a main air suction port, a water detection terminal 23 becomes conductive, and a valve rod 16 moves in the left hand and loses a port 14 opened to the atmosphere rotates the changeover valve 7 in the counterclockwise direction. Thus, the air duct 3 is interrupted and the auxiliary air suction port 6 is opened by the valve body 7c. |
