KR100234046B1 - Excess vibration preventing method for washing machine - Google Patents

Abstract

The present invention relates to a method of preventing excessive vibration of a washing machine to prevent the excessive vibration of the washing tank by unbalance by grasping the motion state of the washing tank when dewatering using a vibration sensor attached to the upper and lower outer tank of the washing machine.

In the conventional method of preventing excessive vibration of a washing machine, when the vibration is largely generated due to unbalance of the lower part of the washing machine, there is a possibility that it may not operate normally, and it is difficult to accurately detect the unbalance amount because the operating state varies depending on the horizontal state in which the washing machine is located. There was this.

In order to solve this problem, the present invention installs a plurality of vibration sensors on the upper and lower portions of the washing tank, and when the dehydration stroke starts, the vibration of the upper and lower portions of the washing tank is sensed through the plurality of vibration sensors, respectively, and then a preset reference vibration signal. While comparing the size and the dehydration stroke for a predetermined time or less according to the result, the debalance amount is measured based on the detected vibration signal, and the dehydration stroke of the washing machine is controlled according to the measurement result. .

Description

How to prevent excessive vibration of the washing machine

The present invention relates to a method of preventing excessive vibration of a washing machine, and in particular, by using a vibration sensor attached to the upper and lower tanks of a washing machine to grasp the state of movement of the washing tank during dehydration, to prevent excessive vibration of the washing tank due to unbalance. It relates to a prevention method.

In the conventional washing machine, as shown in FIG. 1, the washing tank 3 is supported by the washing tank support device 2 inside the outer case 1, and the motor 4 and the clutch 5 inside the washing tank 3. The dehydration tank 6 driven by the is provided. And, to compensate for the unbalance caused by the unbalance of the laundry during dehydration, a balancer (7) filled with about 70% of brine is attached to the top of the dehydration tank (6), and the washing tank (3) is biased when dewatering. The safety switch 8 is attached to the cover of the washing machine to be operated by the physical force of the washing tank 3 when the vibration is more than the width.

In the figure, reference numeral 9 is a pulsator, 10 is a motor pulley, 11 is a clutch pulley, 12 is a V belt, and 13 is a rubber leg.

FIG. 2 is a detailed structural diagram of the safety switch 8, wherein the switch leg 8a is installed to be operated by the physical force of the washing tank 3 when the washing tank 3 is biased and vibrated more than a predetermined width, and the switch leg 8a. ) Is activated, the elastic member for transmitting the action force for restoring the switch leg (8a) to the initial position, as opposed to the physical force caused by the vibration of the switch (8b) and the washing tub (3) installed to be connected to each other interconnected It consists of (8c).

Referring to Figures 1 and 2 attached to the method of preventing excessive vibration of the washing machine using the conventional safety switch configured as described above are as follows.

First, when the washing tank 3 is biased due to unbalance of laundry during the dehydration stroke of the washing machine and vibrates over a predetermined width, the physical force of the washing tank 3 is applied to the switch leg 8a of the safety switch 8. .

At this time, if the applied physical force is higher than the action force of the elastic member 8c, which is an accessory of the safety switch 8, the switch leg 8a is operated so that the plurality of contacts of the switch 8b having their initial state separated are connected to each other. do.

Then, the dehydration stroke is stopped by a separate control process. After the water supply is again, the debalanced laundry is evenly distributed while the pulsation device is turned on / off at a short time interval and the dewatering stroke is performed again.

However, when the safety switch 8 is operated more than a predetermined number of times, the operation of the washing machine is stopped once, and a warning sound is issued to allow the user to manually distribute the laundry in the washing tank 3 to eliminate the unbalanced state. .

On the other hand, when the physical force applied to the switch leg 8a by the washing tub 3 is extinguished, the switch leg 8a is restored to the initial position by the action force of the elastic member 8c, and the plurality of contacts of the switch 8b are initialized. The state is separated again.

However, the conventional method for preventing excessive vibration of a washing machine using a safety switch is not only sensitive to the influence of the external environment, but also a safety switch for detecting the vibration of the washing tank is easily damaged by moisture or large vibrations, which impairs durability or reliability. lost.

In addition, when the vibration is generated largely due to the unbalance of the upper part of the washing tank as shown in Figure 3 (a), when the vibration is largely generated due to the unbalance of the lower part of the washing tank as shown in Figure 3 (b) there was a fear that it may not operate normally. In addition, it is difficult to accurately detect the unbalance amount because the operating state of the safety switch varies depending on the horizontal position of the washing machine or the degree of bending of the switch leg.

Therefore, in some cases, even when the amount of unbalance is large, the dehydration operation is continued due to a detection error, resulting in excessive vibration as well as an abnormal noise caused by friction between the washing tank and the safety switch.

Therefore, the present invention has been proposed to solve the problems of the prior art, by using the vibration sensor attached to the upper and lower tanks of the washing machine to grasp the movement state of the washing tank during dehydration of the washing machine to prevent excessive vibration of the washing tank by unbalance The purpose is to provide a method for preventing excessive vibration.

Technical means of the present invention for achieving the above object, Vibration detection step of detecting the vibration of the upper and lower washing tubs respectively through a plurality of vibration sensors when the dehydration stroke starts; A signal magnitude comparing step of comparing the magnitudes of the respective vibration signals output from the vibration sensor with a preset reference vibration signal; A preliminary dehydration step of selectively performing a dehydration stroke below a predetermined RPM for a predetermined time according to the comparison result of the signal magnitude comparison step, but again detecting vibrations of the upper and lower parts of the washing tank; An unbalance amount measuring step of measuring an unbalance amount based on the vibration signal detected in the preliminary dehydration step; An unbalance amount comparison step of comparing a preset reference unbalance amount and an unbalance amount measured in the unbalance amount measurement step; A high speed dewatering step of selectively performing a high speed dewatering stroke in accordance with the comparison result of the unbalance amount comparison step; According to the results of the signal magnitude comparison step and the unbalance amount measuring step, an unbalance canceling step of selectively stopping dehydration administration and performing an unbalance canceling stroke may be performed.

1 is a conventional washing machine structure diagram.

2 is a detailed structural diagram of the safety switch shown in FIG.

Figure 3 is a vibration form of the washing tub according to the unbalanced position.

Figure 4 is a structure diagram of a washing machine with a plurality of vibration sensors according to the present invention.

5 is a flowchart illustrating a method for preventing excessive vibration of a washing machine according to the present invention.

Figure 6 is a waveform diagram showing the phase difference of the vibration signal according to the translation mode and conical mode vibration form of the washing tank.

Figure 7 is a state showing the translation mode and conical mode vibration form of the washing tank.

8 is an exemplary diagram of a translational or conical mode vibration table according to the present invention.

*** Explanation of symbols for the main parts of the drawing ***

3: washing tank 101: first vibration sensor

102: second vibration sensor

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

4 is a structural diagram of a washing machine with a plurality of vibration sensors according to the present invention, and a first vibration sensor 101 is installed at an upper portion of the washing tank 3 to detect vibration even at a very low frequency. Also, a second vibration sensor 102 having the same performance as the first vibration sensor 101 is provided.

Unexplained reference numerals in the drawings have the same components as the structure of the conventional washing machine shown in FIG.

5 is a flowchart illustrating a method for preventing excessive vibration of a washing machine according to the present invention. When a dehydration stroke is started, a vibration sensing step of sensing vibrations of the upper and lower parts of the washing tank through the first and second vibration sensors ( ST110 to ST120, a first signal magnitude comparison step ST130 for comparing magnitudes of respective vibration signals output from the first and second vibration sensors with a preset reference vibration signal, and optionally according to the comparison result. While performing a dehydration stroke at a predetermined RPM or less for a predetermined time, the preliminary dehydration step (ST140) of detecting vibrations of the upper and lower parts of the washing tank again, and at this time, the magnitudes of the detected vibration signals and preset reference vibration signals A second signal magnitude comparison step ST150 for comparison, a signal phase comparison step ST160 for selectively comparing phases of an upper vibration signal and a lower vibration signal according to the comparison result; If the comparison result is less than the preset reference phase difference, the unbalance amount is calculated based on the detected vibration signal magnitude and the preset parallel mode vibration table, and then the translation unbalance value is compared with the preset reference unbalance amount and the calculated unbalance amount. When the amount comparison step ST161 and the signal phase comparison step are equal to or greater than a preset reference phase difference, the unbalance amount is calculated based on the magnitude of the detected vibration signal and the preset conical mode vibration table. Conical unbalance amount comparison step (ST162) for comparing the set reference unbalance amount and the calculated unbalance amount, a fast dehydration step (ST310) for selectively performing a fast dehydration stroke according to the unbalance amount comparison result, and the signal magnitude comparison step Selectively cut off the power of the motor according to the comparison result of (ST120, ST150) and the unbalance amount comparison step (ST161, ST162) Stop the administration, and may consist of unbalanced relieve step (ST210~ST220) to perform unbalanced relieve stroke.

Referring to Figures 4 to 8 attached to the operation and effect of the present invention configured as described above are as follows.

First, when the dehydration stroke is started, the first and second vibration sensors 101 and 102 installed on the upper and lower portions of the washing tank 3 respectively detect vibrations of the upper and lower washing tanks 3, respectively. ST120)

Then, a separate operation processor (not shown) compares the magnitudes of the respective vibration signals output from the first and second vibration sensors 101 and 102 with the preset reference vibration signal. (ST130)

At this time, if the magnitude of the detected vibration signal is greater than or equal to the reference vibration signal, the motor is cut off to stop the dehydration stroke and perform an unbalance elimination stroke. (ST210 to ST220)

However, when the magnitude of the detected vibration signal is less than the reference vibration signal, the dehydration stroke is performed at a predetermined RPM (eg, 300 rpm) or less for a predetermined time, and the first and second vibration sensors 101 and 102 are washed in a washing tank. (3) The upper and lower vibrations are detected again. (ST140)

In addition, the size of each of the vibration signals detected by the first and second vibration sensors 101 and 102 and the preset reference vibration signal are compared again.

According to the comparison result, if the detected vibration signal is larger than the reference vibration signal, steps ST210 to ST220 are performed. If the detected vibration signal is smaller than the reference vibration signal, the upper and lower vibration signals are separated. Phase is compared (ST160).

At this time, when the phase difference between the two vibration signal is less than the preset reference phase difference, that is, the phase is the same or similar as shown in Fig. 6 (a), the operation processing unit (not shown) shows the vibration form of the washing tank (3). It is judged by the translation mode shown in 7 (a).

Then, the amount of unbalance is calculated on the basis of the detected magnitude of the vibration signal and the preset translation mode vibration table (FIG. 8 is an example of the translation mode or conical mode vibration table), and the calculated unbalance amount and the preset reference unbalance The quantity is compared (ST161).

However, when the phase difference between the two vibration signals in step ST160 is equal to or greater than the preset reference phase difference, that is, when the phase is reversed or different as shown in FIG. The vibration pattern is judged by the conical mode shown in FIG.

Accordingly, the amount of unbalance is calculated based on the detected magnitude of the vibration signal and the preset conical mode vibration table (FIG. 8 shows an example of a translational or conical mode vibration table). The amount of unbalance will be compared. (ST162)

Next, if the amount of unbalance calculated in the above steps ST161 and ST162 is less than the reference unbalance amount, high speed dehydration operation is performed. (ST310)

On the other hand, if the calculated unbalance amount is equal to or greater than the reference unbalance amount, the steps ST210 to ST220, that is, the motor are cut off to stop the dehydration operation and perform the unbalance elimination stroke.

As described above, the present invention has the effect of preventing excessive vibration of the washing tank by unbalance by grasping the movement state of the washing tank when dehydration using a plurality of vibration sensors attached to the upper and lower outer tanks of the washing machine.

Claims (2)

A vibration detection step of detecting vibrations of the upper and lower parts of the washing tank through a plurality of vibration sensors when the dehydration stroke starts; A signal magnitude comparison step of comparing the magnitudes of each vibration signal output from the vibration sensor with a preset reference vibration signal; A preliminary dehydration step of selectively performing a dehydration stroke below a predetermined RPM (RPM) for a predetermined time according to the comparison result of the signal magnitude comparison step, and detecting the vibration of the upper and lower parts of the washing tank again; An unbalance amount measurement step of measuring an unbalance amount based on the vibration signal detected in the preliminary dehydration step; An unbalance amount comparison step of comparing a preset reference unbalance amount and an unbalance amount measured in the unbalance amount measurement step, A high speed dewatering step of selectively performing a high speed dewatering stroke according to a comparison result of the unbalance amount comparing step, And an unbalance canceling step of selectively stopping a dehydration stroke and performing an unbalance canceling stroke according to the result of the signal magnitude comparison step and the unbalance amount measuring step. The method of claim 1, The unbalance amount measuring step may include a signal phase comparison step of comparing a phase of an upper vibration signal and a lower vibration signal detected in the preliminary dehydration step; A translation unbalance amount calculating step of calculating an unbalance amount based on a magnitude of the detected vibration signal and a preset translation mode vibration table when the comparison result of the signal phase comparison step is less than a preset reference phase difference; And a conical unbalance amount calculating step of calculating a conical mode unbalance amount based on the magnitude of the detected vibration signal and the set conical mode vibration table when the comparison result of the signal phase comparison step is equal to or greater than a preset reference phase difference. Transient vibration prevention method of the washing machine characterized in that.

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