A DC brushless motor, comprising: a) a shaft; b) a stator assembly; c) two end covers, each end cover comprising a side wall, a plurality of through holes, and a bearing; d) a housing, the housing comprising: an inner wall, and two ends; e) a plurality of permanent magnets; and f) a plurality of screws; wherein: the shaft is connected with the stator assembly; the stator assembly is arranged inside the housing; the permanent magnets are positioned outside the stator assembly on the inner wall of the housing; each end cover is disposed on one end of the housing; and the shaft is disposed on the bearing of each end cover; characterized in that: each screw extends through one through hole of one end cover and is screwed into the housing; a plurality of gaps is arranged in an axial direction on the side wall of each end cover outside one of the plurality of through holes; a recess in a ring shape is arranged on the side wall of each end cover; the plurality of gaps on each end cover is in communication with the recess; an end of the inner wall of the housing is convex to form a fixture block; the fixture block is inserted into the recess on one end cover through one of the plurality of gaps; an end surface of one end cover is provided with a plurality of clay recesses for correcting a dynamic balance; and a mounting bracket is arranged outside the housing. a) a shaft; b) a stator assembly; c) two end covers, each end cover comprising a side wall, a plurality of through holes, and a bearing; d) a housing, the housing comprising: an inner wall, and two ends; e) a plurality of permanent magnets; and f) a plurality of screws; the shaft is connected with the stator assembly; the stator assembly is arranged inside the housing; the permanent magnets are positioned outside the stator assembly on the inner wall of the housing; each end cover is disposed on one end of the housing; and the shaft is disposed on the bearing of each end cover; characterized in that: each screw extends through one through hole of one end cover and is screwed into the housing; a plurality of gaps is arranged in an axial direction on the side wall of each end cover outside one of the plurality of through holes; a recess in a ring shape is arranged on the side wall of each end cover; the plurality of gaps on each end cover is in communication with the recess; an end of the inner wall of the housing is convex to form a fixture block; the fixture block is inserted into the recess on one end cover through one of the plurality of gaps; an end surface of one end cover is provided with a plurality of clay recesses for correcting a dynamic balance; and a mounting bracket is arranged outside the housing. each screw extends through one through hole of one end cover and is screwed into the housing; a plurality of gaps is arranged in an axial direction on the side wall of each end cover outside one of the plurality of through holes; a recess in a ring shape is arranged on the side wall of each end cover; the plurality of gaps on each end cover is in communication with the recess; an end of the inner wall of the housing is convex to form a fixture block; the fixture block is inserted into the recess on one end cover through one of the plurality of gaps; an end surface of one end cover is provided with a plurality of clay recesses for correcting a dynamic balance; and a mounting bracket is arranged outside the housing.