Invention Grant
- Patent Title: Electric tool
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Application No.: US15322451Application Date: 2015-06-19
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Publication No.: US10173311B2Publication Date: 2019-01-08
- Inventor: Yuuki Takeda
- Applicant: HITACHI KOKI CO., LTD.
- Applicant Address: JP Tokyo
- Assignee: KOKI HOLDINGS CO., LTD.
- Current Assignee: KOKI HOLDINGS CO., LTD.
- Current Assignee Address: JP Tokyo
- Agency: JCIPRNET
- Priority: JP2014-135465 20140630
- International Application: PCT/JP2015/067724 WO 20150619
- International Announcement: WO2016/002541 WO 20160107
- Main IPC: B25F5/00
- IPC: B25F5/00 ; B24B23/02 ; B24B49/10

Abstract:
An electric tool is provided. The electric tool prevents anomalies in motor rotation due to dust and moisture sucked in together with a cooling wind, and is configured such that rotational position detection operations and switch operations are not affected. In the electric tool which drives a brushless DC motor using a controller, a magnetic body for rotational position detection is provided on a rotation shaft which can rotate integrally with a rotor, Hall ICs are provided to detect the rotational position of the magnetic body and output a position signal to the controller, and the magnetic body and the Hall ICs mounted on a substrate are arranged in a region isolated from the wind path of the cooling wind generated by rotation of a cooling fan. The Hall ICs are accommodated in a housing filled with resin.
Public/Granted literature
- US20170136614A1 ELECTRIC TOOL Public/Granted day:2017-05-18
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