| 摘要 |
PROBLEM TO BE SOLVED: To stably control a motor regardless of a sharp change of load at drum start-up.SOLUTION: The drum driving unit comprises: a drum 51 with a rotary shaft having an angle with respect to a vertical direction; a drum motor 60 which has permanent magnets on a rotor 59 for driving the drum 51; and an inverter circuit 71 for supplying a current to the drum motor 60. The inverter circuit 71 comprises: a first operation unit 72; a second operation unit 73; and switching unit 74. The first operation unit 72 generates a signal which is independent from the magnetic pole position of the rotor 59. The second operation unit 73 generates a signal corresponding to the magnetic pole position of the rotor 59. The switching unit 74 starts the drum motor 60 in accordance with the signal from the first operation unit 72, and switches to the signal from the second operation unit 73 after a point where the rotational angle of the drum 51 from the start-up exceeds a first 90-degree. |
