| 摘要 |
PROBLEM TO BE SOLVED: To provide a chisel handheld machine tool such as a handheld hammer drill or a handheld crusher, and a machine tool adapted to the handheld machine tool and suppressing a vibration impact.SOLUTION: A handheld machine tool includes a tool attachment port 2 for attaching a chisel tool on a motion axis 10. A pneumatic hammer mechanism 6 includes: an exciter 12 which reciprocates at a prescribed stroke 24 between a dead point 22 positioned apart from the tool rather than a motor 5 and a dead point 23 positioned near the motor; a hammer 13 which reciprocates on the motion axis 10 between a reversal point 29 positioned apart from the tool and an impact point 28; and an air chamber 15 which is sealed by the exciter 12 and the hammer 13, and transmits the motion of the hammer 13 to the motion of the exciter 12. When the exciter 12 moves to a direction in which the exciter progresses toward the dead point 22 positioned apart from the tool and approximates the dead point 22 positioned apart from the tool by a distance not reaching a half of an entire stroke 24, a control device 39 raises pressure in the air chamber 15. |
