Anti-wiredrawing manual thread locking device for oil cylinder of hydraulic hoist

An oil cylinder wiredrawing-preventing manual thread locking device of a hydraulic hoist comprises an oil cylinder end cover, a gland is arranged on the oil cylinder end cover, a positioning nut and alimiting spring are arranged in the gland, one end of the limiting spring is connected with the bottom of the inner wall of the gland, and the other end of the limiting spring is connected with the bottom face of the positioning nut. By the adoption of the structure, the situation that threads formed by matching of the locking shaft and the piston rod slip and are damaged is avoided, meanwhile, the situation that locking occurs in the locking process is avoided, and the whole device is simple in structure, low in cost and extremely high in practicability. 一种液压启闭机油缸防拉丝手动螺纹锁定装置，包括油缸端盖，所述的油缸端盖上设有压盖，压盖内设有定位螺母和限位弹簧，限位弹簧的一端与压盖的内壁底部连接，限位弹簧的另一端与定位螺母的底面连接。采用上述结构，避免了锁紧轴与活塞杆二者配合的螺纹出现滑丝损坏的情况，同时避免锁定过程中出现锁死的情况，整个装置结构简单，成本低，实用性极强。