PURPOSE: To provide a hand-carried device, including a chisel, a drill and an impact drill, with a tool for assuring torque transmission without causing un expected wear when held by a tool holder, and the tool holder for holding the tool.
CONSTITUTION: A tool includes two locking grooves 1 closed in the axial direction, two driving grooves 2 axially open toward the loose end of a shank, and the shank A having two driving planes 3. A tool holder includes a circularly sectional tool receiving hole, two driving members 4 engaged with the driving grooves 2 in the tool, two locking members 5 adapted to be engaged with the locking grooves 1 in the tool, and counter planes 6 provided in areas on the locking members 5 in the receiving hole corresponding to the driving planes 3 of the tool.
HAINRITSUHI PAURI
AKUSERU NOIKIRUHIEN
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