| 摘要 |
PURPOSE:To inform the abnormality of a pulse generator to the outside without using a special signal line, by reversing one pulse per one rotation outputted from the pulse generator at the time of the abnormality of the pulse generator. CONSTITUTION:A pulse generator (PG)21 outputs one pulse (C-phase pulse) per one rotation and said pulse is subjected to waveform shaping by a waveform shaping unit 22. The C-phase pulse of which the waveform has been shaped is outputted through an exclusive circuit 23 and a transistor 24. When abnormality is generated in the pulse generator, alarm output is generated to be inputted to the exclusive circuit 23 and, therefore, the C-phase output being the output of the transistor 24 is reversed. By this method, C-phase output 'H' inherently having only a predetermined pulse width becomes abnormally long and abnormality is detected at the point of time when said inherent predetermined pulse width is exceeded. |
