| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To detect step-out of a stepping motor and to restart it properly while reducing the manufacturing cost and the size of a printer. <P>SOLUTION: The printer includes: conveyance rollers 52a and 53a which convey a print sheet W on a conveyance path; first and second stepping motors 52c and 53c which drive the conveyance rollers to rotate; a memory 87 which stores the natural frequency band; a vibration sensor 18 which detects vibration; a Fourier transform unit 86a which carries out Fourier transform of the detected vibration; a peak frequency determination unit 85b which determines the peak frequency based on the results of Fourier transform; a step-out decision unit 85c which decides that the first and second stepping motors 52c and 53c have stepped out when the determined peak frequency is not included in the natural frequency band stored in the memory 87; and a drive control unit 86b which controls the start of the first and second stepping motors 52c and 53c when step-out is detected, and drives the conveyance rollers 52a and 53a to rotate. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
