Patent ID: 6597527
Filing Date: 2003-07-22
Classification: G11B

Abstract:
A data storage medium transportation unit comprising:a data storage medium holding block which holds a data storage medium and reciprocally moves between a data storage medium container constituted to contain a plurality of data storage media and a read/write block for reading and writing a data from/to a data storage medium; a motor which is a non-servo motor for driving the data storage medium holding block; a power transmission mechanism arranged between the data storage medium holding block and the motor for converting a rotary power of the motor into a drive force of the data storage medium holding block in its travelling direction; a disc-shaped rotation position detector provided in a rotary portion of the power transmission mechanism and having a plurality of identification areas arranged at an identical interval in a circumferential direction; an optical sensor provided on a non-movable portion of the data storage medium transportation unit and arranged so as to detect the identification areas of the rotation position detector; a speed control block for PWM (pulse width modulation) control of the non-servo motor, said speed control block including a counter for counting the number of identification areas detected by the optical sensor within a predetermined period of time, and a feed speed calculator for calculating a feed speed of the data storage medium holding block according to a value obtained by the counter.