Abstract: An interior stator assembly is provided in a brushless motor which includes an exterior rotor assembly that has a fixed rotating shaft, and a bearing that connects rotatably the exterior rotor assembly to the interior stator assembly. The interior stator assembly includes a coil assembly and two silicon steel plates. The coil assembly includes a sheave which is adapted to journal the rotating shaft of the exterior rotor assembly therein, and a coil which is wound around the sheave. The sheave has two end surfaces on which the plates are fixed. Each of the plates has a ring body and a plurality of angularly equidistant exciting sheets which extend integrally and axially from a circumference of the ring body. The exciting sheets of the plates are staggered in such a manner that each of the exciting sheets of one of the plates is located circumferentially between an adjacent pair of the exciting sheets of the other one of the plates.