| 摘要 |
PURPOSE:To smoothly control a chopper while reducing the power loss by disposing a diode in a direction for discharging a charge stored in a coil for an electromagnetic clutch in parallel with a coil for the clutch. CONSTITUTION:A switch 22 is shifted to upside at the operation starting time to supply a DC current to a coil 50. The switch 22 is shifted to a lowside after the armature is attracted by the coil 50, an interrupted wave is fed to the base of a transistor 23 to flow the interrupted current to the coil 50. When a transistor 30 is ON at the chopper drive time, charge is stored in the coil 50, and the charge stored in the coil 50 is discharged through a diode 60 when the transistor 30 becomes OFF. In this manner, the chopper control can be smoothly performed while reducing the power loss in the chopper control. |
