当P口无压缩空气时，在弹簧力和A 口（腔）余气力作用下；

When P, mouth without compressed air, in spring force and A mouth (chamber) under the action of more than strength;

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当P口无压缩空气时，在弹簧力和A 口（腔）余气力作用下；

When P, mouth without compressed air, in spring force and A mouth (chamber) under the action of more than strength;

youdao