Patent 7048075 was granted and assigned to Hitachi on May, 2006 by the United States Patent and Trademark Office.
A power tool includes a powered drive source, a speed reduction mechanism portion for transmitting a rotational power of the drive source, a striking mechanism portion for converting the rotational power of the speed reduction mechanism portion into a striking force, an end tool for outputting the striking force and a rotational force through the striking mechanism portion, and an impact damping mechanism for damping the impact of the end tool in a direction of rotation of the speed reduction mechanism.