Hand-held power tool

摘要

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.

主权项

1. A hand-held power tool comprising:
a motor; a tool holder; and a percussion mechanism connected in a drive train between the motor and the tool holder, the percussion mechanism including: a first shaft, a second shaft, a hollow wheel connected to the first shaft and whose inside wall is not rotation-symmetrical with respect to an axis of the second shaft, an impeller connected to a second shaft and rotatably situated within the hollow wheel, a magnet situated coaxially to the second shaft, and a magnetorheological fluid filling a cavity between the hollow wheel and the impeller, in a first position, the impeller being spaced apart from the hollow wheel by a first air gap, and in a second position, the impeller being spaced apart from the hollow wheel by a second air gap, the first air gap being smaller than the second air gap, and the impeller and the hollow wheel being made of a magnetically conductive material.