| 摘要 |
PROBLEM TO BE SOLVED: To make the heat radiation effect of a controller itself sufficient, while miniaturizing and thinning a controller having a circuit board and a heat radiation member, in a power tool.SOLUTION: An opposed part 631 of a heat radiation case 61 is provided with a first opposed part 65 for bringing a relative distance near to a plate surface of a circuit board 41 by a first step difference 641 and a second step difference 642. The first opposed part 65 is also linked to an FET 42 so as to be heat exchangeable with the FET 42 while interposing an insulation sheet 80. An electric part arranged on the circuit board 41 is classified into three in accordance with a projection quantity from the plate surface of the circuit board 41, and is collected in a range classified on the plate surface according to three classifications. Here, the first opposed surface 65 is set in response to a first range by the first step difference 641 and the second step difference 642, and the first range is arranged with a first group with the FET 42 for supplying electric power to an electric motor as a group.SELECTED DRAWING: Figure 12 |
