Hammer with air spring percussion mechanism

摘要

In the case of a motor-driven hammer with air spring percussion mechanism, the performance, especially when working soft materials, is to be improved. In this case, an excessively weak recoil of the percussion member led to undesired ventilation processes through the air equalisation hole and thus to a reduction in efficiency. According to the invention, the air equalisation control is effected solely by the drive piston 11, whose seal 14 coincides with an annular groove 15 when at the dead centre close to the tool. Through the annular groove 15 and the longitudinal grooves 17, a defined equalisation of the air-cushion space 18 with the environment takes place exclusively at this point in time. The percussion member 4 is not involved in the control. <IMAGE>