| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a dual-mode system for an inexpensively usable electrically powered double-insulated tool, such as a holding type power tool and an appliance. <P>SOLUTION: The system includes a battery power module 14 and a line power module. The line power module includes a chopper module 21A having a high-efficiency conversion circuit without any filters, and generates power and current required for the power tool. Inductance 22 of a motor 11 for the power tool is used for filtering the output of a chopper module 21A. An output filter is eliminated from the chopper module 21A, thus reducing the cost and size of the line power module. The line power module includes an EMI filter 15 for filtering AC or DC input power. The chopper module 21 chops a filtered voltage, and provide a series of voltage pluses having a DC voltage level suitable for the motor 11 for the power tool. <P>COPYRIGHT: (C)2008,JPO&INPIT |
