Development of an ultra-slim spindle motor for a 3.3-mm-height CF Type I disk drive

This paper presents the development of an ultra-slim spindle motor for a 3.3 mm-height CF Type I disk drive. The mechanical structure of the developed motor is extremely reduced not only by eliminating the unnecessary space but also by optimizing hub and clamp in order to fit in the small form factor. Electrically, it has additional auxiliary windings in the linking part between the adjacent teeth of slotted stator, which increases the torque constant and efficiency. Simulation and experiments are performed to prove the advantages of the developed motor.