JPH02213396A - Control method of washing machine - Google Patents

Abstract

PURPOSE:To accurately detect changes in the turbidity of washing water caused by dirt of the laundry without the affection of forming by a method wherein washing or rinsing operation is controlled according to the data on dirtiness detected by a transmittivity detector when an washing motor is stopped. CONSTITUTION:As for the algorithm for detecting the completion of washing, washing is finished when the changes in the transmittivity becomes less than a specified value for a certain time period. Since the washing water in a water receiving drum contains detergent during washing operation, foaming occurs every time the water is agitated, causing the transmittivity to decrease due to scattering of light. As an accurate turbidity of washing water can be detected without affection of forming while a washing and dewatering motor is out of operation, the output of a transmittivity detector 22 is read just before the washing and dewatering motor is started. Just before an agitator is brought into operation during off-period of the agitator, a transistor 22d is turned on for a time period Ta to supply power to an infrared ray emitting element 13a, and the output voltage of a transmittivity detector 22 is measured in the later half of the period. If the inner wall of the detecting part is filthy, a larger quantity of electric current is applied according to the dirtiness so that the turbidity of the washing water in the drum is accurately detected.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a control device for a washing machine that optically detects the degree of contamination of a liquid in a washing machine and automatically performs a washing or rinsing operation. It is something.

Conventional technology A washing machine control device uses an optical sensor to detect the degree of dirt on laundry and controls washing or rinsing.

For example, there is one shown in Japanese Patent Application Laid-Open No. 61-50595. That is, washing; cleaning the optical sensor consisting of a light emitting element and a light receiving element that optically detects the transparency of water in 1;
After the start of washing, the output of the light receiving element of the optical sensor is captured, the time when the output from this light receiving element decreases to a predetermined value (for example, 20% light transmittance) is defined as dirt degree data, and based on this dirt degree data, The washing and rinsing process was controlled by determining the washing time, rinsing time, and number of rinses.

Problems to be Solved by the Invention However, in the conventional method, which uses the time at which the output from the light-receiving element of an optical sensor drops to a predetermined level as soiling degree data, the amount of dirt from the light-emitting element due to the influence of bubbles generated during washing. Since the light is scattered, the output of the light receiving element is also affected by the shadow 1 of the bubbles, making it difficult to accurately detect the change in IT of the washing liquid due to dirt falling from the laundry.

Therefore, the present invention solves the above-mentioned conventional process, and accurately detects changes in the turbidity of the washing liquid due to dirt falling from the laundry without being affected by the bubbles generated during washing. Alternatively, the primary purpose is to control the rinsing operation.

The purpose of $2 is to make it less susceptible to bubble shadow 1 and to improve detection accuracy.

A third objective is to provide a wash cycle that is less susceptible to foam shadow I.

Furthermore, the fourth purpose is to eliminate the bubble shadow J by data processing.

Means for Solving the Problems The first technical means of the present invention for achieving the above-mentioned first object is to provide a transmittance detector for detecting the light transmittance of the liquid in the washing motor and a washing motor. The apparatus is equipped with a control means for controlling the washing or rinsing operation using the output data of the transmittance detector of OFF4 as data on the degree of contamination of the liquid. A second technical means of the present invention for achieving the second object is that the transmittance detector has a peak hold circuit for holding the Beakshi pressure within one predetermined time.

In addition, the third technical means of the present invention to achieve the third objective is a transmittance detector that detects the light transmittance of the liquid in the tank, a washing machine, and a normal ON/OFF switch of one motor. Longer than the cycle 1. -> Set an OFF period periodically, and its length is 1 AO
The apparatus is configured to include a control means for controlling the washing or rinsing operation using the output data of the transmittance detector during the F period as data on the degree of contamination of the liquid.

A fourth technical means of the present invention for achieving the fourth objective is a transmittance detector that detects the light transmittance of the liquid in the tank;
Measure the output data of the transmittance detector at regular intervals during pouring or rinsing operation, and average the measured data of n times, including the measured data at any time t and the past (n-1) measured data. The apparatus is equipped with a control means for opening the washing A or rinsing operation, using the moving average value as data on the degree of contamination of the liquid at time t.

According to the first technical means described above, data from the transmittance detector is used as dirt degree data when the washing motor is turned off, which is less susceptible to the effects of foam generated during washing. To accurately detect changes in washing liquid due to dirt falling from objects, and control the washing time according to the degree of dirt on the laundry and the appropriate rinsing time according to the amount of detergent used. becomes possible. , Mata. According to the second technical means, it is possible to remove fluctuations caused by bubbles in the peak hold circuit and the transmittance detector, so that detection accuracy can be further improved.

Moreover, according to the technical means 'a3, the washing motor is turned on.
, longer than the OFF time of the OFF cycle -0#F, IJJ
li! ff is set and the detection data is taken in during that period, so the influence of bubbles is extremely small.

Furthermore, according to the fourth technical means, since the dirt degree data is created using a moving average value that also includes past data of the light transmitting vehicle detector, the influence of fluctuation components due to bubbles can be reduced, and the data processing The impact can be suppressed.

EXAMPLE 1 Hereinafter, a case will be described in which an example of the present invention is applied to a fully automatic washing machine.

Figure 3 is a cross-sectional view of the fully automatic washing machine. 1 is the outer frame, 2
3 is a washing and dehydrating tank; 6 is for switching the power of the washing and dehydrating motor 5 so as to rotate the stirring blade 4 during washing or rinsing, and the washing and dehydrating tank 3 during dehydration. This is a power switching mechanism. T is an air pocket for generating pressure corresponding to the water level, 9 is an air hose for transmitting the pressure generated in the air pocket 7 to the water level detection means 8, and 1o is a water receiver for collecting the liquid in the tank 2. 11 is a drainage hose; 12 is a water supply valve for supplying tap water into the tank 2;

The water receiver 13 is a transmittance detection part for detecting the transmittance of the liquid in the tank 2, and as shown in FIG.
3! It is composed of L and a light receiving element 13b.

Next, FIG. 1 shows the configuration of a control device for a fully automatic washing machine.

In the figure, 14 is an input means for setting which process of washing, rinsing, and dehydration is to be performed and the water level; 16;
Reference numeral 8 indicates a display means for informing the user of the contents set by the input means 14, the progress of washing, etc., and the water receiver 8 is a water level detection means for detecting the water level in the tank 2 and generating an electric signal. 16 and 17 are bidirectional thyristors for driving the washing and water pumping motor 6, 18 is a bidirectional thyristor for driving the water supply valve 12, 19 is a bidirectional thyristor for driving the drain valve 10, 20 is a commercial power source, 21 is a power switch, and 22 is a water receiver that outputs data according to the degree of contamination of the liquid in the tank 2. Reference numeral 23 denotes a microcomputer (hereinafter referred to as microcomputer) which is a control means for inputting the output data of the transmittance detector 22 and controlling the operations of each process of washing A, rinsing, and dehydration.

FIG. 4 shows an example of the transmittance detector 22.

In the figure, 22a is composed of a PWM circuit and a D/MU converter, and an infrared light emitting element 13 receives a signal from a microcomputer 23.
It is a constant current source to flow a constant current to &. 22b and 220 are resistors, 22(i is a transistor that receives a signal from the microcomputer 23 and controls the ON/oty of the current flowing to the infrared light emitting element 13&, 22. is a peak hold circuit,
Since 22t has one converter and one circuit is passive, the explanation of its operation will be omitted.

FIG. 6 is a timing chart showing the measurement timing of the output voltage of the transmittance ejector 22.

Immediately before the next stirring starts during the OFF period of the stirring blade 4, the transistor 22d is turned on for a time Ta to turn on the infrared light emitting element 1.
A current is passed through 31L, and the output voltage of the transmittance detector 22 is measured in the latter half.

here,! Since the time for "h" is several seconds and the time for "h" is several milliseconds, the infrared light emitting element 13
The duty cycle for passing current through & is approximately 171,000
It has the characteristic of being able to instantaneously flow a large current. Therefore, even if the inner wall of the sensing portion is dirty, if a large amount of current is applied in accordance with the dirt, the degree of dirt in the liquid inside 1 can be detected with high accuracy in the same manner as when the inner wall is not dirty.

The first embodiment of the present invention will be described with reference to FIG. -7 As the laundry gets dirtier, the water tray picks up the liquid in layer 2, so the washing time becomes longer [as time passes, the light transmittance decreases, but the dirt on the surface is almost gone. In the dark state, the light transmittance hardly changes. FIG. 9 shows this situation. In the figure, curve a is curve 1 when the amount of dirt is small, curve 1 is the curve 1 when the amount of dirt is medium, and curve 0 is the change in light transmittance with respect to washing time when the amount of dirt is large.
The transmittance becomes approximately constant after time ta, tb, and tc, respectively. That is, at time t&, tb, respectively
, to, the washing is completed, so the algorithm for detecting the completion of washing may be that the washing is completed when the change in transmittance for a certain period of time becomes equal to or less than a certain value. However, since detergent is mixed in the liquid in the tank 2 of the water receiver during washing, bubbles are generated every time the washing is stirred, and the bubbles scatter light, causing WL to decrease the transmittance. That is, each time the liquid is stirred, the transmittance increases or decreases regardless of the degree of stagnation of the liquid. This situation is shown in Figure 1Q.

From the figure, when the washing/drying motor 6 is turned on, the transmittance decreases, and when it is turned off, the transmittance increases. The degree of stagnation of the liquid without the influence of bubbles is shown by the broken line in FIG. 10, so it is sufficient to read the output of the transmittance detector 22 during the OFF period of the washing and dewatering motor 6, just before it is turned ON. . This will be explained based on the flowchart of FIG. 6. In step 100, the microcomputer 23 turns on the washing and dewatering motor 6 for a time Ton, and in step 1o1 it turns it on for a time T. ff is turned off, the output voltage of the transmittance detector 22 is measured in step 102, and it is determined in step 103 whether washing has been completed. Also, during washing, as shown in Fig. 10, the transmittance does not necessarily change in synchronization with the ON/OFF of the water motor 6 before washing, but as shown in the upper part of Fig. The peak voltage rises and falls, but through the peak hold circuit 220 that holds the peak voltage for a period slightly longer than "of" f in FIG. 4, as shown in the lower diagram of FIG.
The output voltage of the peak hold circuit 220 immediately before N is turned into a smooth curve as shown by the broken line in the same figure, and is hardly affected by bubbles.

Next, a second embodiment of the present invention will be described based on chart 70 of FIG. Microcomputer 23? i step 20
After clearing the timer at 0, the timer is started at step 201, and the washing/extracting motor 5 is operated for a time T at step 202. After being turned ON for n times, it is determined in step 203 whether the timer is running for 1 minute or not. If the timer has not been scratched for 1 minute, the pre-washing water motor 6 is turned on for time T in step 204. Only ff is 0
FFj.

Then, the process returns to step 202. Conversely, if one minute has elapsed in step 203, there is a delay of three seconds in step 206, and the output voltage of the transmittance detector 22 is measured in step 206, and this value is set as Vn. At step 2o, it is determined whether the washing is completed based on the value of Vn. That is, a three-second pause period is provided for every minute of washing to maintain a state with few bubbles, and the end of washing is determined based on the liquid permeability during that period.

Further, a third embodiment of the present invention will be explained based on the flowchart of FIG. 8 and the characteristic diagram of FIG. 12. The microcomputer 23 performs initial value setting in step 300.1. vn
All lvo1#vO21vo31v04 are set to 0.

In step 301, 4 is incremented by 1, and in step 302, the value of v03 is changed to v04, and the value of v02 is changed to v.
Put the values of o and vo into v02, and put the value of vn into vo. In step 303, the water motor 6 is turned ON for only a certain period of time, and then in step 304
In step 305, the output voltage of the transmittance detector 22 is measured. In step 306, if l<6, proceed to step 301 (F), if 11≧6, in step 307, calculate the sJJ average of Vn and the past 4 data, a total of 6 times, and calculate this moving average value. shall be. In step 308, it is determined whether the washing is completed based on the r ratio of l/n. Namely.

Since the data measured once is greatly affected by bubbles, the moving average value of six measurements including the past four measurements is calculated to reduce the bubble shadow 1. Figure 12 shows the seven articles.

In this embodiment, the method of controlling when the end of washing is detected has been described, but the shadow 1 of the bubbles can be made smaller during the control during rinsing as well as during washing. In addition, the washing motor is normally ON/
As a specific example of making the OFF period periodically longer than the OFF cycle to reduce the bubble shadow 1,
We used a method of measuring transmittance with a rest period of seconds, but
This may be paused every 30 seconds or 2 minutes, or the pause period may be set to 6 seconds, etc., with the same effect. Furthermore, as a method of calculating the moving average value, a method was used in which the data of 6 times were averaged, but it goes without saying that the data can be further stabilized by increasing the number of times, such as 7 times or 10 times.

Effects of the Invention As described above, according to the present invention, when the washing motor is turned off,
In other words, since the output of the light transmittance detector is used as dirt degree data at a time when it is less affected by the foam generated during washing, changes in the turbidity of the washing liquid due to dirt falling from the laundry can be accurately detected and washing or rinsing operations can be performed. can be done automatically,
Further, there is an effect that no harmful effects such as a decrease in cleaning efficiency are caused.

In addition, the influence of bubbles can be significantly suppressed by the peak hold circuit, and detection accuracy can be further improved. Also,
Since the OFF time of the washing motor is lengthened to sufficiently eliminate the influence of foam, countermeasures against foam can be taken with simple operation control. Furthermore, since the moving average value using past data is used as dirt degree data, the influence of foam is eliminated, and since it is data processing, there is no need for a special anti-foam circuit or washing operation. .

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a control device for a fully automatic washing machine according to an embodiment of the present invention, FIG. 2 is a circuit diagram of a transmittance detector according to an embodiment of the present invention, and FIG. 4 is a sectional view of a transmittance detection section of an embodiment of the present invention, FIG. 6 is a timing chart for explaining measurement,
6, 7 and 8 are flowcharts of one embodiment of the present invention, FIGS. 91, 10, 11 and 1.
FIG. 2 is a characteristic diagram showing an embodiment of the present invention. 2...Water receiver is a tank, 6...Washing and dewatering motor. 13... Transmittance detection section, 22... Transmittance detector. 22G...Peak hold circuit, 23...
...Microcomputer. Name of agent: Patent attorney Shigetaka Awano and one other person

Claims (4)

[Claims] (1) A transmittance detector that detects the light transmittance of the liquid in the tank, and control that controls the washing or rinsing operation using the output data of the transmittance detector when the washing motor is OFF as data on the degree of contamination of the liquid. A washing machine control device comprising means. (2) The washing machine control device according to claim 1, wherein the transmittance detector has a peak hold circuit that holds a peak voltage within a predetermined time. (3) A transmittance detector that detects the light transmittance of the liquid in the tank, and an O that is longer than the normal ON/OFF cycle of the washing motor.
A control device for a washing machine, comprising a control means that periodically sets an OFF period and controls a washing or rinsing operation using output data of the transmittance detector during the long OFF period as data on the degree of dirt of the liquid. (4) A transmittance detector that detects the light transmittance of the liquid in the tank, and the output data of the transmittance detector is measured at fixed time intervals during washing or rinsing operation, and measurement data at an arbitrary time t is provided. and the past (n-1) measurement data (n is a natural number), and the moving average value obtained by averaging the measurement data of n times is used as the liquid dirt degree data at time t, and the control means controls the washing or rinsing operation. Washing machine control device equipped with.