| 摘要 |
PURPOSE: To make a noise reduction in a lumber working machine employing a single phase electric source as an electric source input by preventing the damage and breakage of an endless belt. CONSTITUTION: Single phase voltage inputted from a single phase electric source is converted into three phase alternating voltage by a converter circuit 18 and inverter circuit 19, and a motor 18 (three phase induction electric motor) is rotation driven utilizing the three phase alternating voltage as an electric source. Control signals for controlling the inverter circuit 19 is set previously in a control device 20 for rising a frequency at an acceleration time not exceeding an allowable transmission torque of the endless belt. Also, a regenerative braking circuit 21 for stopping the motor 8 is connected to the inverter circuit 19 in parallel at a deceleration time generating a deceleration torque not exceeding the allowable transmission torque of the endless belt preliminarily set in the control device 20. |
