发明名称 Electric power tool
摘要 According to an aspect of the invention, an electric power tool which includes a brushless direct-current motor and a drive circuit that supplies drive power to the motor, and which rotates or drives a tool, characterized in that the drive circuit includes plural switching elements, and is arranged on a board provided in a grip portion of a housing or below the grip portion; and an electric fan is provided in the vicinity of the switching element for cooling the switching element.
申请公布号 US9590475(B2) 申请公布日期 2017.03.07
申请号 US201314106609 申请日期 2013.12.13
申请人 Hitachi Koki Co., Ltd. 发明人 Oomori Katsuhiro;Tokairin Junichi;Uchida Hiroki
分类号 B25F5/02;H02K9/06;B25F5/00;H02K7/14 主分类号 B25F5/02
代理机构 Kilpatrick Townsend & Stockton LLP 代理人 Kilpatrick Townsend & Stockton LLP
主权项 1. A power tool comprising: a motor including a rotational shaft extending in a front-rear direction; a fan attached to the rotational shaft; a circuit board including a plurality of switching elements; and a housing including a body portion, a handle portion, and a battery retaining portion; the body portion accommodating the motor and the fan; the handle portion extending from the body portion and including an airflow passage in which the circuit board is arranged; the battery retaining portion including an air intake, wherein a wall portion is located between the fan and the circuit board in a radial direction of the fan, is configured to prevent air from flowing from the fan to the circuit board, and includes an opening for airflow from the handle portion into the body portion, and wherein rotation of the fan generates a flow of air that flows through the air intake to the airflow passage, through the airflow passage to the opening, through the opening to the body portion, and inside the body portion.
地址 Tokyo JP