| 摘要 |
PURPOSE:To control the temperature of a motor, without requiring a temperature detecting element such as a thermister, by predicting current temperature based on temperature rise characteristics during operation of motor and temperature drop characteristics during pause of motor and then comparing thus predicted temperature with the dangerous temperature, i.e., a prescribed temperature, of motor thereby controlling the motor. CONSTITUTION:A monitor circuit 4 adds the count in a counter 5 with a rate correlative to temperature rise characteristics when a drive signal (DR signal) fed from a control circuit 3 is 'H', whereas decreases the count in the counter 5 with a rate correlative to temperature drop characteristics when the DR signal is 'L' thus predicting current temperature of a motor 1. When the output from a first comparator circuit 6 is 'H', the control circuit 3 outputs an 'L' DR signal to disable a motor drive circuit 2 so as to stop operation of the motor 1 while furthermore provides an alarm from an alarm unit 7. When the output from a second comparator circuit 9 is 'O', the control circuit 3 outputs an 'H' DR signal to restart the motor 1 and to interrupt provision of an alarm from the alarm unit 7. |
