Handheld grinder with a brushless electric motor
US9314900B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 18, 2013 |
| Grant date | Apr 19, 2016 |
| Priority date | — |
| Expiry date | Oct 18, 2033 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02K7/145
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A handheld grinder comprising a housing; a grinding disk; a motor; an output shaft connected to the grinding disk and the motor to impart rotary motion thereto; and a circuit board residing in the housing and having thereon a rectifier that receives an alternating current and converts the alternating current to a direct current, a switching arrangement having a plurality of motor switches connected electrically between the rectifier and the motor and operates to deliver the direct current from the rectifier to the motor, a capacitor connected electrically between the rectifier and the switching arrangement, wherein the capacitor is coupled in parallel across the rectifier, a driver circuit interfaced with the motor switches and operable to control switching operation of the motor switches, and a power switch connected electrically between the rectifier and the driver circuit and operable to selectively energize the driver circuit and power on the grinder disk.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.