| 摘要 |
PURPOSE:To obtain an inexpensive brake unit with a simple structure by regeneratively braking a motor until the frequency generated by an inverter becomes minimum, operating a switch unit when the frequency becomes lower than the minimum, and releasing the motor from the inverter, thereby dynamically braking the motor. CONSTITUTION:When a start switch 5 is opened to stop a motor 3, the output frequency of an inverter 2 is lowered rapidly to the prescribed frequency, and the motor 3 is decelerated by regenerative braking proportionally to the output frequency of the inverter 2 from a point c to a point d. The output of the inverter 2 becomes minimum frequency at the point d, and becomes zero at the point lower than the point d. At this time, a brake unit 8 actuates to open a switch 9 with a stopping signal generated from the inverter 2, and a switch 10 is closed. Accordingly, the induced power of the motor 3 is consumed in the coil by the generative braking, and the motor 3 is decelerated rapidly from the point d to the point f, and is stopped. |
