The rapid development of computer technology and automation technology has greatly promoted the development of medical equipment automation system. Automatic control technology is widely used in the field of medical devices. Among them, automation system effectively improves work efficiency and reduces production costs in the medical industry. As the core component of automation, motor has been widely used in many equipment and instruments in the medical industry, such as all kinds of body fluid analyzer, bone drill, tooth drill, biochemical analyzer, ultrasonic imager, injection pump and other equipment. At the same time, the motor is required to have the following characteristics. Low noise, stable quality , the low interference Small volume , high precision , low vibration , and quick reaction .