| 摘要 |
<p>A control device (40) is provided with a switching valve mechanism (41) and first and second actuators (71, 79). The switching valve mechanism (41) is provided with a valve element (61) for switching which is located within a casing (42). The valve element (61) can linearly move between an open position at which first and second pressure change chambers (45, 47) of the casing (42) are communicated with each other and a closed position at which the communication is interrupted. The valve element (61) is held at the open position and the closed position by a first holding mechanism (toggle spring (70)). When a float (72) ascends to a first water level (HWL), the first actuator (71) moves the valve element (61) from the closed position to the open position. When the degree of vacuum within a pressure detection chamber (94) becomes a second degree (P2) of vacuum or less, the second actuator (79) moves the valve element (61) from the open position to the closed position.</p> |
