| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a highly efficient shredder which copes with voltage fluctuation in commercial power and fluctuations in the load. <P>SOLUTION: The shredder comprises a three-phase induction motor 1 for driving a shredding mechanism, a direct-current power supply unit 4 which is connected with the input side of the three-phase induction motor 1 and converts power from a commercial power source 3 into a direct current, an inverter 2 which turns power from the direct-current power supply unit 4 into three-phase and supplies it to the three-phase induction motor 1, a detector which detects the load on the inverter 2, and a controller 7 which generates a command signal to the inverter 2 based on a detected load signal from the detector. The direct-current power supply unit 4 has an active filter power source 6. Based on the detected load signal, the controller 7 issues to the direct-current power supply unit 4 a signal for changing the width of switch-on of the active filter power source 6 of the direct-current power supply unit 4. Further, the controller 7 issues a signal for changing the frequency to the inverter 2. <P>COPYRIGHT: (C)2004,JPO&NCIPI |
