极限开关：吊上吊下都有极限开关部件，防止链条超出确保安全。

Limit switch: using limit switch component in designation to protect chain and ensure and security.

youdao

极限开关：吊上吊下都有极限开关部件，防止链条超出确保安全。

Limit switch: using limit switch component in designation to protect chain and ensure and security.

youdao