Patent ID: 9048699
Filing Date: 2015-06-02
Classification: B25F,H01L,H02K,H05K,Y02P

Abstract:
1. A power tool comprising: a brushless motor including a rotation shaft extending in a front-rear direction; a fan attached to the rotation shaft; switching elements that drive the brushless motor; a circuit board on which the switching elements are mounted; a tip end tool hold portion that holds a tip end tool; a transmission portion that transmits a driving force of the brushless motor; and a housing that houses the brushless motor, the fan, the switching elements, the circuit board and the transmission portion therein and includes suction openings formed on a periphery side of the circuit board and a rear side of the circuit board and an opening formed at a periphery portion of the fan, wherein the switching elements include semiconductor elements each having terminals on a bottom surface thereof, wherein the switching elements are surface mounted on the circuit board, and wherein the fan is configured to draw air into the housing from the suction openings formed on the periphery side and the rear side of the circuit board such that the air flows along a surface of the circuit board and is exhausted to the outside of the housing from the opening formed at the periphery portion of the fan.