| 摘要 |
A powered hammer is described comprising a housing (3), a tool holder (20) mounted on the housing (3), a percussion mechanism (9) arranged within the housing (3) which mechanism includes a ram (17) reciprocating in a longitudinal direction and being adapted to apply impacts on a tool bit (19) supported in the tool holder (20), a dampening mass (23) which is slidably mounted in the longitudinal direction within the housing (3), wherein the dampening mass (23) is biased towards a neutral position by a biasing element (25, 27) and wherein the dampening mass (23) may be deflected from the neutral position against the biasing force of the biasing element (25, 27). The dampening mass (23) is formed of a ferromagnetic or paramagnetic material or comprises a permanent magnet and a solenoid is arranged within housing adjacent to the dampening mass (23) such that the solenoid (31) applies a force in the longitudinal direction on the dampening mass (23) when being in the neutral position if a current is flowing through the solenoid (31). |
