倒装置 meaning in English

focusing device
focusing mechanism

Application of new inversion - proof device in shelter roadway
新型防倒装置在架棚巷道中的应用
A simple and aplicable tension - rod antitoppling equipment of powered support
一种简单实用的棚架拉杆防倒装置
Development of collapseproof install of i - steel shed in five driving roadway
王庄煤矿炮掘巷道支架防倒装置的研制
Anti - collapse equipment of roadway support excavated by blasting in wangzhuang coal mine
炮掘巷道工字钢棚防倒装置的研制