摘要 |
A cylinder (15) is reciprocable in the housing (11) of a hydraulic percussive tool and a piston hammer (16) is reciprocable in the cylinder. The force between the cylinder and the housing is constant during the cycle of reciprocation and as a result the housing (11) is practically not vibrating at all. The piston hammer (16) and the cylinder (15) are coupled together to move conjointly during a part of each forward stroke of the hammer piston, which ensures the timing of the reciprocation of the hammer piston 16 and the cylinder (15). |