Electric power tool
US8872398B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | May 8, 2012 |
| Grant date | Oct 28, 2014 |
| Priority date | — |
| Expiry date | Jul 3, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02K7/145
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
There is disclosed an electric power tool in which magnetic saturation seldom occurs in a tooth of a stator without increasing the size of a motor. The electric power tool includes a motor having a stator with a plurality of teeth formed circumferentially at equal intervals and axially extending groove-like slots between each tooth, with winding wires being wound around each tooth by use of the slots, and having a tubular rotor coaxially surrounding the stator with a permanent magnet of a plurality of poles on an inner peripheral surface facing distal end surfaces of the teeth of the stator. Further, the ratio of the number of poles of the permanent magnet of the rotor to the number of slots of the stator is set to be 4 to 3.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.