Washing machine

Abstract

The invention provides a washing machine for an electric detection for the weight unbalance owing to deflection of the washings to one side or the like, wherein the abnormal vibration of the longitudinal shaking is detected by a first detection mechanism and a second detection mechanism and the abnormal vibration of the transverse shaking in the high speed rotation is detected by a third detection mechanism. The first detection mechanism determines whether a washing dewatering tank has the unbalance by comparing a difference of the rotation speed at a prescribed interval and a prescribed threshold when the rotation speed of a motor is increased to a low speed superior target rotation speed. The second detection mechanism determines whether the washing dewatering tank has the unbalance by comparing a difference between a duty ratio reduction and the reference duty ratio reduction and the threshold, wherein the duty ratio is used for maintaining the low speed superior target rotation speed. In the third detection mechanism, the change of the duty ratio in the high speed rotation is observed and threshold is switched based on the reference duty ratio so as to stop control of the motor.

Description

technical field [0001] The present invention relates to a washing machine, in particular to a vertical washing machine having a washing and dehydrating tank with an open top surface which can rotate around a vertical or inclined axis. Background technique [0002] In a typical vertical fully automatic washing machine, a bottomed cylindrical outer tank is suspended and supported by a suspension rod for absorbing vibrations. Inside the outer tank, there is also a bottomed cylindrical outer tank with a surrounding opening. A washing and dewatering tank with a plurality of dehydration holes, and the washing and dewatering tank can freely rotate around a vertical or inclined axis, and at the inner bottom of the outer tank, a pulsator (stirring blade) for stirring (such as Refer to Patent Document 1, Patent Document 4, etc.). [0003] In such a washing machine, the laundry is dehydrated by rotating the washing and dehydrating tank integrally with the pulsator at a high speed. Vi...

AI Technical Summary

Problems solved by technology

In addition, when the mechanical accuracy is low due to the deviation of the mounting position of the magnet or Hall element of the motor, or the surface vibration accuracy of the rotor of the motor, etc., even during normal rotation, it may be judged that rotation has occurred. Unbalanced and detected as unbalanced

[0008] In addition, as described in Patent Document 1 or Patent Document 3, in the state where the rotational speed of the motor is kept at a set stable target high-speed dehydration rotational speed (for example, 800 rpm), it is desired to detect When there is an imbalance, if the imbalance is obvious, there may be a large vibration before the imbalance detection is performed when the rotation speed reaches the stable target high-speed dehydration speed.

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