Industrial Technology Research Institute

Sunonwealth Electric Machine Industry Co., Ltd.

Chi-Mou Zhao

Yin-Rong Hong

Der-Ray Huang

Alex Hong

Shyh-Jier Wang

Min-Der Wu

Tai-Fa Ying

Chin-Po Liao

Chiang Cheng Huang

Han Chung Wang

Eric-G Lean

A spindle motor for a disc drive, such as a CD-ROM drive, is provided. This spindle motor is a brushless motor of a single-phase axial-winding and radial-gap type including a stator, a rotor coupled to said stator, and a driving circuit for supplying a driving signal to the stator to rotate the rotor. The stator includes a pair of upper and bottom salient-pole pieces formed with a plurality of tooth-like portions serving as salient-poles. The peak surface of each tooth-like portion is formed into a symmetrical convex shape, which minimizes the cogging torque of the motor. Further, the use of a phase-adjuster in the driving circuit allows the motor to produce large output torque at high speeds. The output characteristics of this spindle motor meet the requirements of high speed CD-ROM drives.

Spindle motor for optical disc drives

An automatic phase adjuster for the driver of a brushless motor is provided. This automatic phase adjuster can output a driving signal adaptively with a suitable phase-lead or phase-lag angle so as to allow the motor to be operated with the optimal output characteristics, including optimal output torque, optimal output efficiency, and optimal output power at all speeds. The automatic phase adjuster is configured variously in accordance with the particular type of the motor on which the automatic phase adjuster is used. For single-direction motors operated at a fixed speed, the automatic phase adjuster includes a phase-lead filter coupled to a Hall sensor which detects the motor speed. For single-direction motors operated at various speeds, the automatic phase adjuster includes a phase-lead filter, a phase-lag filter, a multiplexer, and a Hall sensor. The multiplexer selects either the phase-lead filter or the phase-lag filter to process the motor speed signal. For dual-direction motors operated at various speeds, the automatic phase adjuster includes a phase-lead filter, a phase-lag filter, a multiplexer, and a Hall sensor. The multiplexer selects either the phase-lead filter or the phase-lag filter depending on the direction and acceleration/deceleration condition of the motor. This allows the motor to be always driven with optimal performance.

Automatic phase adjuster for a brushless motor driving signal

Growing community of inventors

Taipei Hsien, Taiwan

Chi-Mou Zhao