摘要 |
The rotating tool (8) such as a pipe hammer is equipped with a breaker device (5,6) which interrupts operation of the motor drive (7) to the tool (8) according to the operating state determined by a sensor (1). The turning angle of the machine tool (M) is calculated using a time constant (t) derived from a sensor (1) which determines the amount of turning movement. The breaker device (5), (6) is activated when the amount of turn exceeds a maximum permitted turning angle. |