Hand-held power tool
US9539708B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 17, 2012 |
| Grant date | Jan 10, 2017 |
| Priority date | — |
| Expiry date | Jan 8, 2034 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16D2037/002
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A hand-held power tool has a motor, a tool holder, and a percussion mechanism disposed between the motor and the tool holder in the drive train. The percussion mechanism includes a first shaft and a second shaft. A magnetically conductive ring gear is connected to the first shaft. An inner wall of the ring gear is eccentric to an axis of the second shaft. A magnetically conductive impeller is connected to the second shaft and is arranged to rotate within the ring gear. The impeller is spaced from the ring gear by a first air gap in a first position while being spaced from the ring gear by a second air gap in a second position, the first air gap being smaller than the second one. A magnet array is arranged coaxially to the second shaft. A magnetorheological fluid fills a cavity between the ring gear and the impeller.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.