| 摘要 |
<p>PURPOSE:To make accurate torque detection with a simple circuit constitution by performing the torque detection by means of the armature current value of a motor. CONSTITUTION:A load is driven by a motor 1 through a reduction gear which is not shown in the figure. The voltage of an electric current detecting device, for example, a resistance 3 which detects the armature current of the motor 1 corresponds to the armature current, namely, load torque. When the load increases and the voltage of the resistance 3 exceeds the sum of voltage drops of resistances 10 and 11, the output of a comparator circuit 6 becomes a high level and, therefore, the output of an AND circuit 12 also becomes a high level and the output of an FF circuit 13 becomes a low level. At this time, a large reduction gear ratio is selected at the reduction gear and the load is driven. Since a time determined by a delay circuit 15, namely, the output of the delay circuit 15 is a high level, the set input of the FF circuit 13 is inhibited. Therefore, malfunction at the time of transition condition following to the speed change is eliminated.</p> |
