Self-locking socket spanner

The utility model relates to the field of socket wrenches, in particular to a self-locking type socket wrench which comprises a socket body, a square opening is formed in one end of the socket body, external threads are formed in the position, corresponding to the square opening, of the outer wall of the socket body, a through opening penetrating through the square opening is formed in the position of the external threads of the socket body, and a pin body is arranged in the through opening. The pin body is connected with the sleeve main body through the elastic piece, the threaded sleeve is in threaded connection with the threaded portion of the outer wall of the sleeve main body, the threaded sleeve is rotated for axial position adjustment, the pin body is pressed by the threaded sleeve to sink into the through opening, the interior of the pin body and a shaft body of the electric wrench are provided with a radial combination portion, and the sleeve main body is stably connected with an output shaft of the