| 摘要 |
PURPOSE:To effectively perform the closing operation of a gas shut-off valve at the time of an earthquake or the like by providing a latch means for latching a switching handle at the open position against a return spring which urges the handle of the valve in its closing direction and releasing the latch of the handle by the dropping operation of a magnet at the time of earthquake or the like. CONSTITUTION:When a switching handle 4 is switched to its open side, as shown, a lever 10 is strongly urged upwardly by a spring 9, and a pivotting hole 18 of the handle 4 is moved to the side of a latching arm 26 from a linear line which connects the other pivotting hole 19 to the pivotting hole 14 of a plate- shaped arm 12. Accordingly, the handle 4 is latched at the position. At this time one end of the arm 12 is latched by a pawl 27 of the arm 16, and a valve body 8 is maintained at its open position. When a magnet 5 drops from an attracting plate 31 due to an earthquake in the above stae, the pawl 27 will be disengaged so that the one end of the arm 12 is not supported, with the result that the valve body 8 is urged upwardly by the spring 9. Thus, the valve is closed. Then, the handle 4 is returned to the original position by a spring 11. |
