| 摘要 |
<p>PURPOSE:To prevent the damage by burning of a motor, by connecting a program changing circuit to a tape inverter as well as to a motor driving stop circuit via a counter and then stopping the motor when a prescribed count number is obtained with no stop of the tape inverter. CONSTITUTION:When a tape inverter 2 has no operation owing to mixture of a foreign matter or other factors, a detection switch 5 has no switching and is kept open. Therefore no coincidence is obtained between the OFF signal given from the switch 5 and inverted by an NOT gate 9 and the ON signal stored at a latch circuit 7. Thus the signals of H levels are consecutiviely delivered from a signal coincidence circuit 8 and then counted by a counter 3 via an NOT gate 10. Since the inverter does not operate, the instruction given from a program change command circuit 1 is repetitively fed to the counter 3. When this command frequency reaches a prescribed level, an instruction is delivered to a motor driving stop circuit 4 to stop the motor. This prevents the damage by burning for the motor.</p> |
