阀门的启闭位置由行程开关控制，且阀板上设有限位挡块以保证阀板的启闭位置。

There is limit block on the valve disc to ensure the open-close position , which is controlled by the stroke switch.

youdao

机器采用液压电气控制，滑块行程可任意调节，机械挡块，扭轴同步、平稳可靠；

Hydraulic and electrical control is applied to the machine , with free adjustment of stroke for the gliding block, as well as stable and reliable mechanical stopper and synchronized tension bar.

youdao