倒扣接头的结构见图,公扣为正扣,母扣为反扣。作用原理是:胀大接头8下端是开有三道槽子的公扣,内孔带有一定锥度。在公扣与落鱼母扣对上扣时慢转4～5圈(不需紧扣)就可上提钻具。胀大轴9向上移动,使胀大接头的公扣张开起锁紧作用,在倒扣 Back buckle connector structure shown in Figure, the male buckle is buckle, the female buckle buckle. The principle of action is: Expansion joint 8 is open at the bottom of the three slots buckle, the hole with a certain degree of taper. In the public deduction with the deduction of the fish on the deduction buckle turn 4 to 5 laps (without fastening) can be put on the drill. Swollen shaft 9 moves upward, so that the expansion of the male joint buckle open the locking effect, in the buckle