Title:
ELECTRIC TOOL
Document Type and Number:
WIPO Patent Application WO/2019/187991
Kind Code:
A1
Abstract:
[Problem] To provide an electric tool in which a brushless motor has favorable accuracy in detecting the rotation of a rotor while securing the torque of the rotor. [Solution] Provided is a percussion driver drill, as an electric tool, comprising a brushless motor that includes a rotor 24 and a sensor circuit board for detecting the rotation of the rotor 24. The rotor 24 is provided with a cylindrical rotor core 110 and four permanent magnets 112 held inside the rotor core 110 so as to extend along the axis of the rotor core 110. The sensor circuit board is provided adjacent to a front end (first end) of the rotor core 110. In an outer side surface between the adjacent permanent magnets 112, the rotor core 110 has a recessed groove 122 extending along the axis thereof in the range from the front end to a point not reaching a rear end (second end), which is an opposite end to the front end.
Inventors:
AOYAMA KIYOSHI (JP)
Application Number:
PCT/JP2019/008184
Publication Date:
October 03, 2019
Filing Date:
March 01, 2019
Export Citation:
Assignee:
MAKITA CORP (JP)
International Classes:
H02K11/215; B25F5/00; H02K1/27
Foreign References:
| JP2016116267A | 2016-06-23 | |||
| JP2016178751A | 2016-10-06 | |||
| JP2009112121A | 2009-05-21 |
Attorney, Agent or Firm:
ISHIDA Yoshiki (JP)
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