Patent 7325811 was granted and assigned to Hilti on February, 2008 by the United States Patent and Trademark Office.
A chuck (2) for a hand-held power tool (4), which is connected with a motor-driven spindle (6) of the power tool for joint rotation therewith, includes a locking device for securing a shaft section of an exchangeable working tool and having a circular cross-section in the chuck (2) without a possibility of axial displacement and rotation relative to the chuck (2), with the locking device having a clamping element (12; 34) for securing the shaft section (8), and an element (18) for transmitting rotation to the shaft section (8) and rotationally separated from the clamping element (12; 34) by a rotary bearing (2).