An improved eccentric type self-locking nut fundamentally solves the problems of looseness and the like under the working conditions of high vibration frequency, high vibration strength, long vibration period and the like in the prior art and comprises a
lower body and an upper body, an eccentric boss is arranged on the upper portion of the
lower body, and an eccentric hole is formed in the lower portion of the upper body. The eccentric type self-locking nut is technically characterized in that the eccentric boss of the
lower body and the eccentric hole of the upper body are connectively fixed in a close fit manner through a thin-walled sleeve with a
frustum, the external
diameter of the eccentric boss of the lower body is as same as the internal
diameter of the thin-walled sleeve with the
frustum, the internal
diameter of the eccentric hole of the upper body is as same as the external diameter of the thin-walled sleeve with the
frustum, axial central lines of the eccentric boss, the eccentric hole and the thin-walled sleeve with the frustum as well as a thread
central line of the upper body and a thread
central line of the lower body deviate from a same eccentric axis when the eccentric boss, the eccentric hole and the thin-walled sleeve with the frustum are in the initial state, and an axial initial distance is set between the end of the upper body and the end of the lower body. The eccentric type self-locking nut is simple in
processing technology, reasonable in bearing after being matched with a connecting bolt, convenient to
mount and demount like a common nut and capable of using own looseness moment to achieve a locking function, and has the advantages of capability of remarkably improving nut looseness preventing effect, more benefit to reuse and the like.