Self-locking tuning assembly with self-locking tuning screw

A self-locking tuning assembly, comprising:

• a tuning screw comprising a head portion and a rod portion extending from the head portion along a first direction;
• the head portion being provided with a first threaded portion and a second threaded portion which are spaced apart from each other along the first direction;
• a cover plate defining an opening and a cavity communicating with the opening along the first direction;
• the opening configured to receive and fix the tuning screw;
• and
• a resonance rod located in the cavity;
• wherein the opening comprises a first hole portion and a second hole portion communicating with the first hole portion along the first direction;
• a hole diameter of the second hole portion is smaller than a hole diameter of the first hole portion;
• and
• when the tuning screw is fixed to the cover plate, the first threaded portion and the second threaded portion is located and fixed in the first hole portion, and the rod portion passes through the second hole portion along the first direction and partially extends into an inside of the resonance rod.