Often in ac circuit by air damping model time relay, it is to use the principle of air through orifices throttling to obtain delay action.

在交流电路中常采用空气阻尼型时间继电器，它是利用空气通过小孔节流的原理来获得延时动作的。

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Early in the circuit often USES air damping model time relay, it is to use the principle of air through orifices throttling to obtain delay action.

早期在交流电路中常采用空气阻尼型时间继电器，它是利用空气通过小孔节流的原理来获得延时动作的。

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