Self-locking drill chuck

A self-locking drill chuck, comprising a drill body, a nut, a clamping jaw, a self-locking structure, a rotating sleeve, wherein the rotating sleeve is provided with a convex leaf spring fixed to a rotating sleeve at both ends, the nut or ring fixedly connected with the nut are provided with a first groove and a second groove matching with the convex portion of the leaf spring, the first groove is a groove corresponding to the drill chuck in the self-locking state, and the second groove is a groove converting from self-locking state to unlocking state corresponding to the drill chuck;

• the self-locking structure comprises a ring tooth on the drill body and rotatable locking block arranged on the nut or ring fixedly connected to the nut, the nut or ring fixedly connected to the nut is provided with a leaf spring, the rotating sleeve is provided with a first part compressing the leaf spring and a second part compressing the locking block, and by compressing the leaf spring via the first part, the leaf spring compresses the locking block, to rotate the locking block and engage with teeth on the drill body, drill chuck enters self-locking, and through compressing the locking block by the second part, the locking block reverses to break away from the tooth, a gap between the rotating sleeve and the tooth is provided with for lifting the locking block out of the tooth.