Nut control device

摘要

A control device for preventing a nut from loosening, comprises a first member having an external thread portion, a second member having an internal thread portion screwed with the external thread portion and an opening, a locking coil which is wound around the external thread portion of the first member and has at its both ends bent portions to be selectively engaged with the opposite sides of the opening of the second member, and a third member which is rotatably fitted in the second member and engaged or disengaged with the bent portions of the locking coil.