Twisting and tightening mechanism in reinforcement binding machine

摘要

In a reinforcement binding machine in which a wire feed device (3) feeds externally therefrom a wire (2) for binding reinforcements and the wire fed out by the wire feed device (3) is bent in a loop shape by a guide part, a twisting-and-tightening mechanism (5) comprises: a pair of hooks (19) being capable of opening and closing, for gripping in part the wire wound around the reinforcements in the loop shape; a driver for rotating the hooks (19) in a direction to twist the wire (2) gripped and for selectively moving the hooks (19) toward or apart from the reinforcements with the wire wound therearound; and a coil spring for urging the hooks such that the hooks are normally spaced apart from the reinforcements.