| 摘要 |
<p>PURPOSE:To make effective use of high-pressure gas that a puffer chamber generates so as to enhance the arc-extinguishing performance of a puffer type gas circuit breaker by restraining blowing out of gas at the initial stage of the period of breaking action. CONSTITUTION:A nozzle 25 for concentrating on an arc high-pressure gas flowing out of a puffer chamber is connected via a spring 27 so that the position of the nozzle 25 is variable relative to a movable-side arc contact portion 24. In the first stage of the period of breaking action, the spring is held in an expanded state as long as pressure within the puffer chamber 30 is low, and then the nozzle makes contact with the end of the arc contact portion, thus restraining flowing out of the gas while preventing flowing out of gas that does not serve to extinguish the arc. When the gas pressure exceeds a predetermined value, the spring is contracted by forces exerted on the nozzle and the nozzle is separated from the arc contact portion so that a gas circulating passage is formed and the high-pressure gas is blown out, whereby the high-pressure gas that the puffer chamber generates is effectively utilized in the extinction of the arc.</p> |
