JPS628796A - Automatic water feeder of washing machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to an automatic water supply device for a washing machine, and more particularly to a device that automatically supplies water in an amount corresponding to the amount of laundry.

``Prior art'' If the amount of water supplied is less than the amount of laundry, there is a risk of damaging the laundry, and if it is too much, water and electricity will be wasted.

Therefore, it is necessary to supply an appropriate amount of water depending on the amount of laundry.

An example of an automatic water supply device for a conventional washing machine is to supply water to the washing tub to a predetermined low water level and operate the washing motor.
The steady value of the input terminal of the laundry motor is measured, and the amount of laundry is determined based on its size. If the amount of laundry is determined to be a small amount, water supply is completed at that point, and if it is determined to be a medium amount, water is supplied to the specified medium water level. The system is configured to add water, and if it is determined that the amount is larger, the water is added up to a predetermined high water level.

Since the input current of the washing motor has a characteristic that increases according to the amount of load, if the input current is large, it is determined that the amount of load, that is, the amount of laundry is large, and water is added accordingly.

"Problems with the Prior Art" In the above-mentioned conventional automatic water supply device for a washing machine, water is simply supplied to a low water level without stirring, so the laundry does not contain sufficient water. However, after the water level became low,
When the laundry is stirred, the water content of the laundry is promoted, so that the water level is lowered from the low water level by the amount of water content after stirring.

For this reason, when the amount of laundry is larger than the medium amount, the extent to which the water level is insufficient and becomes a load becomes considerably large in both cases, and the proportion of the difference in the amount of laundry that can be detected as a difference in load becomes small.

Therefore, when the amount of laundry is larger than a medium amount, the accuracy of determining the amount of laundry decreases. There are problems such as water supply being completed at the water level.

``Object of the Invention'' An object of the present invention is to provide an automatic water supply bag E for a washing machine that can accurately supply water according to the amount of laundry even when the amount of laundry is larger than a medium amount.

``Structure of the Invention'' The automatic water supply device for a washing machine of the present invention includes a water supply means for supplying water into a washing tub of a washing machine, a water level sensor for detecting the water level in the washing tub, and a predetermined set water level using the water level sensor. water supply control means for supplying water by the water supply means until water is detected; a stirring means for stirring the interior of the washing tub with water supplied to the set water level; Discrimination means for determining whether the water is large or small, and if the discrimination result is large, perform the water supply and stirring 5 discrimination based on a new set water level higher than the set water level, repeat these steps, and if it is determined to be small Alternatively, it is characterized in that it is provided with a water supply completion means that completes the water supply when the water supply reaches a predetermined upper limit water level.

"Function" When laundry is placed in the washing tub of a washing machine, water is supplied to a predetermined water level, and the water is stirred, the water level changes as follows depending on the amount of laundry.

■ If the amount of laundry is in balance with the amount of water supplied or less than that, the laundry is almost completely submerged in water, and the amount of water contained in the laundry is sufficient, so even if the laundry is agitated, the amount of water added will increase. is small, so there is almost no drop in water level in this case.

■ If the amount of laundry is larger than the amount of water supplied, the laundry will not be completely submerged in the water and some parts will remain above the water surface. These parts become hydrated by capillary action, but not fully; however, when agitated, these parts also have time to be drawn into the water, during which time the hydration is accelerated. The water content increases depending on the amount of laundry. Therefore, in this case, the water level decreases according to the amount of laundry.

Therefore, the inventors of the present invention focused on this point, conducted research, and completed the present invention.

That is, in the present invention, water is supplied to a predetermined set water level, agitation is performed, a drop in the water level is detected, and if the magnitude of this drop is greater than a predetermined comparison value, it is determined that the amount of laundry is greater than the amount of water supplied. and add water. As this process is repeated, water is supplied until the amount of laundry and the amount of water supplied reach a balance.

Since such determination is repeatedly performed, the accuracy of the determination is high even when there is a large amount of laundry, and an appropriate amount of water is always supplied.

"Example" The present invention will be described in more detail below based on the example shown in the drawings. Here, FIG. 1 is a schematic structural explanatory diagram of an example of a washing machine including the automatic water supply device of the present invention, and FIG. I
Figure 3 is a flowchart of the main parts related to the function of the automatic water supply device in the washing machine shown in Figure 4, and Figure 4 is a characteristic diagram showing changes in agitation time and water level. be. Note that the present invention is not limited to the embodiments shown in the figures.

A washing machine 1 shown in FIG. 1 has a water supply valve 2. Water level sensor 3, washing and dehydration tank 4. Water tank 5. Pulsator 6, drive mechanism 7. It basically includes a motor 8 and a control circuit 10.

Here, other components except for the control circuit IO are the same as corresponding conventionally known components. The control circuit 10 differs from the prior art in that it functions as an automatic water supply device according to the present invention.

As shown in FIG. 2, the water level sensor 3 is, for example, a semiconductor strain gauge type pressure sensor, and changes its resistance value depending on the water level.

The change in resistance value is output by the amplifier circuit 11 of the control circuit 10 as a water level signal d.

The water level signal d is input to the microcomputer 13 as a peak hold value e by the peak hold circuit 12 of the control circuit IO.

The microcomputer 13 reads the operator's instructions via the operation unit 14. It also controls the water supply valve 2 and motor 8.

Furthermore, the peak hold value e output from the peak hold circuit 12 is read, and the peak hold circuit 12 is cleared for the next peak hold.

Next, with reference to FIG. 3, automatic water supply processing in the washing machine 1 will be described.

The operator puts the laundry Q into the washing and dehydrating tank 4, and presses the operating section 1.
When the water supply instruction is given from 4, microcomputer 1
3 enters the process shown in FIG. 3(a).

First, the microcomputer 13 clears the peak hold circuit 12. (Sl) Next, open the water supply valve 2,
Start water supply (S2), read the peak hold value e output by the peak hold circuit 12, continue water supply until a predetermined low water level is detected (S3), and turn off the water supply valve 2 when the water level becomes low Do (34).

Next, a water level drop detection process (S5) is performed. The water level drop detection process is a series of processes shown in FIG. 3(b).

That is, in the water level drop detection process, first the peak hold value e is read (521).The value thus read represents a low water level, and this value is stored in the memory M (S22).

Next, n is set to 1 (S23) and incremented (324) to n-2. This n is a conventional means for repeatedly reading five peak hold values e, as will be described later.

Next, the peak hold circuit 12 is cleared to prepare for a new peak hold (325).

Next, set the time T0 for turning on the motor 8 326
), the motor 8 is turned on for the set time T0 (S27
, 28.29).

Next, set the time T for turning off the motor 8 (530).
), the motor 8 is turned off for that time Tf (331).

The on time T0 of the motor 8 is, for example, 0.5 seconds, and the off time T is, for example, 1 second.

After turning off the motor 8 for a time Tf, the peak hold value e is read (S32) and stored in the memory Mn (3
33), if n=2, it is stored in the memory M2.

The above steps S24 to S33 are repeated until n=6 in step 334, and five peak hold values e are stored in the memories M2 to M6.

When the peak hold value e of 5111 is obtained, their average value is calculated, and the average value is subtracted from the low water level stored in the memory M+ to calculate the water level decrease numerator (S
35).

When a water level drop molecule is obtained by the water level drop detection process, it is determined whether the value of T is negative (36).

If the water level drop numerator is negative, either there is no drop in the water level at all, or on the contrary, the water level is rising, so it is presumed that there was no part of the laundry Q that protruded above the water surface. The amount of water supply is judged to be sufficient. Water supply is completed there.

On the other hand, if the drop numerator of the water level is 0 or positive, the water supply valve 2 is turned on (37), water is supplied until the middle water level is detected (S8), and the water supply valve 2 is turned off at the middle water level (39). ,
In other words, water supply is added up to the mid-water level.

Now, FIG. 4(a) shows the water level fluctuation when the motor 8 is repeatedly turned on and off at a low water level.

When the motor 8 is driven and the pulsator 6 is rotated, the water also rotates, and the peripheral portion of the water in the washing and dehydrating tank 4 is lifted up by centrifugal force.

Such a state is indicated by H in FIG.

When the peripheral part of the water in the washing and dehydrating tank 4 lifts up, the water between the washing machine and hydrophilic tank 4 and the water tank 5 is drawn into the washing and dehydrating tank 4 due to the so-called pump effect, as shown by h in FIG. As such, the water level between the washing and dewatering tank 4 and the water tank 5 is lowered.

When the pulsator 6 stops, the raised water surface H returns to its original level, so that the lowered water surface rises to its original height. Also, due to inertia, it becomes higher than the original water surface.

As a result, the water level detected by the water level sensor 3 repeats small vertical fluctuations as the pulsator 6 continuously operates.

On the other hand, as a result of the agitation, even if the laundry Q initially appears to be floating in the water, it is drawn into the water and becomes even more hydrated. Therefore, the water level is lowered from the original low water level by the amount of water contained in the laundry Q.

The magnitude of the decrease is proportional to the amount of water contained in the laundry Q, which in turn is proportional to the amount of laundry Q.

In this way, a water level change characteristic as shown in FIG. 4(a) is obtained.

Here, W is the case of only water, and although the water level fluctuates slightly up and down due to the pump effect, the average water level remains low.

A is a case where the amount of laundry is small (for example, 500 g), and there is a small vertical fluctuation due to the pump effect and a decrease in the water level due to water content.

However, due to the resistance caused by the laundry Q, the pumping effect is slightly reduced, and the amplitude of the vertical fluctuation is smaller than that for W.

In addition, since the laundry Q is small, it is almost completely submerged under the water surface and contains sufficient water, so the water level does not drop much due to agitation, and the maximum value of the fluctuation is above the low water level. be. Therefore, the water level decrease numerator becomes a negative value, and water supply is completed at a low water level in step S6.

B is a case where the amount of laundry is medium (for example, 1-).

The amplitude of the vertical fluctuation due to the pump effect is smaller than in A. On the other hand, the drop in water level due to water content is large (lowering) because there are many parts that protrude above the water surface.
The value of the water level decrease numerator becomes a positive value, and the above step s6
Water supply will be added.

In case C, when the amount of laundry is large (for example, 2 pupils), the amplitude of the vertical fluctuation due to the pump effect is even smaller, and on the other hand, the drop in water level due to water content is lower than in case B because there are many protruding parts above the water surface. It's getting bigger. Therefore, the value of the water level decrease numerator in this case is positive, and the above step s6
Water supply will be added.

When water is supplied to the middle water level, the water level drop detection process is performed again (S10).

This water level drop detection process is as described above with reference to FIG. 3(b). However, the reference water level stored in the memory M1° is the middle water level.

FIG. 4(b) shows the fluctuation of the water level at the middle water level. Here, W' indicates the case where only water is used, B' indicates the case where the amount of laundry is medium, and C' indicates the case where the amount of laundry is large.

When the amount of laundry is medium, the laundry Q is almost completely submerged under the water surface up to the medium water level, and the water content is almost complete.
No drop in water level was observed even with stirring.

On the other hand, when the amount of laundry is large, a portion of the laundry Q that protrudes above the water surface remains, and as a result of stirring, it is further absorbed with water, and the water level is lowered by the amount of water absorbed.

Therefore, the water level drop molecule takes a negative value when the amount of laundry is medium, and takes a positive value when the amount of laundry is large.

Thus, if the amount of laundry is medium and the water level decrease numerator is negative, water supply is completed up to the medium water level (S11).

On the other hand, if the water level decrease numerator is not negative, then the water level has decreased, so it is considered that the amount of water supplied is less than the amount of laundry, and more water is supplied. That is, the water supply valve 2 is turned on (S12).

However, since there is an upper limit to the amount of water that can be stored in the washing and dehydrating tank 4, if water is supplied until a high water level is detected (S1
3) The water supply valve 2 is turned off (S14), and the water supply is completed.

Note that, as shown in 4th VIJ (c), at a high water level, the laundry Q is submerged under the water surface, and even if the amount of laundry is large, the water level does not decrease due to stirring.

As can be understood from the above description, according to the washing machine 1, water is supplied to the extent that the laundry Q can be submerged under the water surface.

However, in a natural state, the laundry Q floats, so even if such water supply is performed, a part of the laundry Q may appear to protrude above the water surface.

In another embodiment, instead of focusing on the decrease in water level from a set water level such as the low water level or medium water level, the water levels may be compared directly, which also substantially reduces the decrease in water level. This is because it is equivalent to comparing .

Moreover, as the value of the water level that fluctuates up and down, instead of taking the peak value as described above, a value that takes a minimum value of the up and down fluctuation, a value that takes an intermediate value of the up and down fluctuation, etc. can be mentioned.

Furthermore, instead of the two levels of setting values of low water level and medium water level as in the above embodiment, there may be one in which three or more levels of setting values are provided.

"Effects of the Invention" According to the present invention, there is provided a water supply means for supplying water into the washing tub of a washing machine, a water level sensor for detecting the water level in the washing tub, and a water level sensor that detects the water level until a predetermined set water level is detected by the water level sensor. A water supply control means for supplying water by the water supply means, an agitation means for agitating the inside of the washing tub W1 with water supplied to the set water level, and whether a drop in the water level from the set water level due to the agitation is larger or smaller than a predetermined comparison value. If the determination result is large, perform the water supply and stirring 1 determination based on a new set water level higher than the set water level, repeat these steps, and if it is determined to be small or a predetermined upper limit An automatic water supply device for a washing machine is provided, characterized in that it is equipped with a water supply completion means that completes water supply when water is supplied up to a predetermined water level, whereby the amount of water supplied is The balance of the amount of laundry is checked and it is determined whether to complete water supply or add more, so even if the amount of laundry is medium or above, water can be supplied appropriately.

Therefore, it is possible to eliminate damage to laundry and waste of water, electricity, etc. due to mismatch between the amount of laundry and the amount of water supplied.

[Brief explanation of drawings]

FIG. 1 is a schematic structural explanatory diagram of an example of a washing machine including the automatic water supply device of the present invention, FIG. 3
The figure is a flowchart of main parts related to the function as an automatic water supply device, and FIG. 4 is a characteristic diagram showing changes in stirring time and water level. (Explanation of symbols) 1...Washing IJSt2...Water supply valve 3...Water level sensor 4...Washing and dewatering tank 8
...Motor 10...Control circuit 12.
...Peak hold circuit 13...Microcomputer.

Claims (1)

[Claims] 1. A water supply means for supplying water into a washing tub of a washing machine, a water level sensor for detecting the water level in the washing tub, and a water supply control means for supplying water by the water supply means until a predetermined set water level is detected by the water level sensor. , an agitation means for agitating the interior of the washing tub while water is being supplied to the set water level, a determining means for determining whether a decrease in the water level from the set water level due to the agitation is greater or less than a predetermined comparison value, and a determination result thereof. If the water level is large, the water supply, stirring, and determination are performed based on a new set water level that is higher than the set water level, and these are repeated, and water supply is completed when it is determined that the water level is small or when water has been supplied to a predetermined upper limit water level. An automatic water supply device for a washing machine, comprising a water supply completion means.