self closing device

基本解释

Door shall become self-closing on interruption of signal to release device.
当释放装置信号中断时自动关闭。
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Doors of engine casing and stair casing on main deck are of fire doors with self-closing device.
主甲板机舱棚围壁和梯道环围等处安装的门为带闭门器的防火门。
When the partition is running, the wicket is always at closing state for the guarantee of self-lock device. So, there will be no accident when the wicket is suddenly opened.
屏风在运行中，有自锁装置的保护，小门始终处在关闭状态，这样就不会因小门扇的突然张开而带来意外。