| 摘要 |
An impact drill minimizing transmission of vibration to a handle gripped by a user's hand. A spindle extends through a main frame and is movable in its axial direction and rotatable about its axis. A first ratchet is rotatable and axially movable together with the spindle. A second ratchet is axially movable but unortatable. The first ratchet has a first serrated surface and the second ratchet has a second serrated surface in confrontation with the first serrated surface. In an impact drilling mode, the first serrated surfaces is brought into abutment with the second serrated surface so that the spindle is reciprocally moved in the axial direction. A first spring is interposed between the main frame and the second ratchet to urge the second ratchet toward the first ratchet. A second spring is interposed between the main frame and the second ratchet to urge the second ratchet away from the first ratchet. In the impact drilling mode, the second ratchet is always out of contact from the main frame and is floatingly maintained within the main frame.
|
