| 摘要 |
<P>PROBLEM TO BE SOLVED: To enable a rotation speed sensor to be eliminated, to reduce costs and to increase reliability while maintaining the rotation speed controlling performance in a drum-type washing machine. <P>SOLUTION: A separate excitation direct current motor 4 is used for the motor, and at the same time, this drum-type washing machine is equipped with an armature resistance calculating section 71, a rotation speed calculating section 72, and an applying voltage setting section 73 as a controlling mechanism 7 for controlling the separate excitation direct current motor 4. In this case, the armature resistance calculating section 71 calculates an armature resistance from an armature current being measured for a specified period and an inter-terminal voltage being applied at that time in the middle of a deceleration until the motor 4 stops after a field current is zeroized in the step of repeating the start/stoppage of the motor 4 by turning on/off of the field current. The rotation speed calculating section 72 calculates the rotation speed of the motor 4 with the armature resistance, the armature current and inter-terminal voltage as parameters. The applying voltage setting section 73 calculates the inter-terminal voltage which should be applied at least based on a deviation between an estimated rotation speed being the rotation speed which has been calculated by the rotation speed calculating section 72, and a target rotation speed. <P>COPYRIGHT: (C)2009,JPO&INPIT |
