| 摘要 |
PROBLEM TO BE SOLVED: To switch a selector valve with smooth operation and small buoyancy by promoting the simplification of structure upon reducing the number of part items. SOLUTION: A float 3, a selector valve 4 and snap mechanism 5 are all built in a hermetically sealed vessel 2. This snap mechanism is composed of a rocker shaft 35 supported in this hermetically sealed vessel, a float arm 34 and a sub arm 38 rotating around this rocker shaft, a spring bearing part 40 formed in the float arm at a point distant from the rocker shaft, another spring bearing part 41 formed in the sub arm at a point apart from the rocker shaft, a turnover plate spring 39 set up in space between both these spring bearing parts 40 and 41, and a restraint member 42 restraining any curve of this turnover plate spring and making it turn over. In this connection, the float is connected to the float arm, while the selector valve is connected to the sub arm via a valve stem operating rod 28. |
