Oki ML520 User Manual
Page 50
Page: 34
Service Guide ML520/521
Chapter 2 Principles of Operation
Space Motor Control
The SP/LF motor driver (Location 5A: MHM2025) drives the three-phase brushless motor. Motor
movement is based on the phase signal (SPU, SPV and SPW) and the speed instruction data from the
LSI. The MPU can identify the current speed of the space motor by measuring the pulse width of the
output (Phase A, Phase B) of the encoder disk sensor.
After comparing the target speed for each print mode with the actual speed, the motor is accelerated or
decelerated to maintain the desired speed for each print mode.
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