JP2705197B2 - Washing machine control device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a washing machine in which a degree of contamination of a liquid in a tub is optically detected and a washing or rinsing operation is automatically performed. is there.

2. Description of the Related Art Conventionally, Japanese Patent Application Laid-Open No.
As disclosed in Japanese Patent Publication No. 595, a washing degree detector for optically detecting a change in turbidity of the washing liquid is provided, and a washing or rinsing operation is automatically performed based on output data of the washing degree detector. There is a machine control device.

SUMMARY OF THE INVENTION However, in the above-described washing machine control device, the influence of bubbles generated at the time of washing is large, and it is difficult to accurately detect a change in turbidity of the washing liquid due to dirt falling from the laundry. there were.

Therefore, the present invention solves the above-mentioned conventional problems, and performs washing or rinsing operation by accurately detecting a change in the turbidity of the washing liquid due to dirt falling from the laundry so as not to be affected by bubbles generated during washing. And to prevent adverse effects such as a decrease in cleaning efficiency.

Means for Solving the Problems In order to solve this object, a control device for a washing machine according to the present invention includes a light emitting element and a light receiving element for detecting a degree of contamination of a liquid in a tub, and turning on and off a current flowing through the light emitting element. A switching unit, a maximum value detection unit that detects a maximum value of the output of the light receiving element in a plurality of ON and OFF operations of the switching unit, and at least washing or cleaning the output of the maximum value detection unit as a degree of liquid contamination. Control means for controlling the rinsing operation.

Effect of the Invention According to the present invention, a change in turbidity of a washing liquid due to dirt falling from laundry is accurately detected without being affected by bubbles generated at the time of washing, and an appropriate washing time and It is possible to control with an appropriate rinsing time according to the amount of detergent used. Further, since the water flow is not weakened or the stirring is not stopped for detecting the transmittance, there is no possibility of causing a bad effect such as a decrease in cleaning efficiency. Furthermore, the current flowing to the light emitting element by the switching unit is turned OFF and OFF.
Therefore, a large current can be instantaneously passed through the light emitting element, and the degree of contamination of the liquid can be accurately detected.

Embodiment Hereinafter, an embodiment in which the present invention is applied to a fully automatic washing machine will be described with reference to the drawings.

FIG. 2 is a cross-sectional view of a fully automatic washing machine, where 1 is an outer frame,
Is a water receiving tank, 3 is a washing and dewatering tub, 6 is a power for switching the power of the washing and dewatering motor 5 so as to rotate the stirring blade 4 during washing or rinsing, and rotate the washing and dewatering tub 3 during dewatering. It is a switching mechanism. Reference numeral 7 denotes an air reservoir for generating a pressure corresponding to the water level, 9 denotes an air hose for transmitting the pressure generated in the air reservoir 7 to the water level detecting means 8, and 10 denotes the liquid in the water receiving tank 2. , A drain hose, and 12 a feed valve for supplying tap water into the water receiving tank 2. Reference numeral 13 denotes a transmittance detecting unit for detecting the transmittance of the liquid in the water receiving tank 2, and includes an infrared light emitting element 13a and a light receiving element 13b as shown in FIG.

Next, FIG. 1 shows a main configuration of the fully automatic washing machine. In the figure, reference numeral 14 denotes an input method for setting which of washing, rinsing, and dehydrating processes to operate, a water level, and the like, and 15 denotes a user such as the contents set by the input means 14 and the progress of washing. Display means for informing, 8 is a water level detecting means for detecting the water level in the water receiving tank 2 and generating an electric signal, 16 and 17 are bidirectional thyristors for driving the washing and spinning motor 5, and 18 is water supply. A bidirectional thyristor for driving the valve 12, a bidirectional thyristor 19 for driving the drain valve 10, a commercial power supply 20, a power switch 21 and a water receiving tank 2
A transmittance detector for detecting the degree of contamination of the liquid in the inside, 23 is a peak hold circuit for finding the maximum value of the output signal of the transmittance detector 22 within a predetermined period, and 24 is a maximum value detecting means. A / D output signal of peak hold circuit 23
It is a microcomputer (hereinafter referred to as a microcomputer) as a control means for controlling the operation of each step of washing, rinsing, and dehydrating based on the data which is input to the conversion unit, A / D converted, and based on the data. FIG. 4 shows the transmittance detector 22 and the peak hold circuit.
An example of 23 is shown. 22a includes a PWM circuit and a D / A converter, and receives a signal from the microcomputer 24 to receive an infrared light emitting element 13a.
22b and 22d
Is a resistor, and 22c is a transistor for controlling ON / OFF of a current flowing to the infrared light emitting element 13a based on a signal from the microcomputer 24. The peak hold circuit 23 includes transistors 23a and 23d, an electrolytic capacitor 23b, and a resistor 23c. Since the circuit is general, detailed description of the operation is omitted.

A first embodiment of the present invention in a fully automatic washing machine having the above configuration will be described with reference to a timing chart of FIG. The microcomputer 24 inverts the stirring blade 4 with the ON period being T _on and the OFF period being T _off. Asynchronously with this, the cycle is T _b (for example, 1 second) and the transistor 22c is turned _on by T _a (for example, 0.01 second).
N is applied to the infrared light emitting element 13a. At that time, the base potential V _{1 of the} transistor 23a depends on the transmittance of the transmittance detector 13.
Changes as shown in FIG. In order to detect the maximum value between the predetermined time T _c of the voltage value of each the T _b (for example, 10 seconds), and input to the A / D converter of the microcomputer 24 via a peak hold circuit 23, following T _c The transistor 23d is turned on to detect the maximum value during the period, and the output voltage V _{O of the} peak hold circuit 23 is turned on.
A / D conversion is performed and _VO is measured just before the OV is set to OV. Thus, by taking the maximum value of the values of V ₁ of the n calls between predetermined time T _C, as shown in the characteristic diagram of FIG. 6, the true laundry without the influence of the bubbles generated in the wash The turbidity change of the liquid can be detected.

In the above, an example in which the maximum value detecting means is realized by an electric circuit has been described.
Will be described with reference to FIGS. 7 and 8. FIG. In this case, the peak-hold circuit of FIG. 3 and 4 in the figure was not needed, a configuration in which the output voltage V ₁ of the permeability detector 22 is input to the A / D converter of the direct microprocessor 24. This will be described below with reference to the flowchart of FIG. Microcomputer
In step 24, initial settings are made in steps 100 and 101, and V _max = O and N = 1. Followed by turning ON the transistor 22c supplying a current to the infrared light emitting element 13a at step 102, after a delay of T _a (for example, 0.01 seconds) at step 103, the V ₁ input at step 104 and A / D conversion This value is V ₁ (N)
In step 105, the transistor 22c is turned off. At step 106, it is determined whether or not V ₁ (N) ≧ V _max .
_{If 1} (N) ≧ V _max , the process proceeds to step 108 as V _max = V ₁ (N) in step 107. If N = 10 at step 108, then at step 111, V _O = V _{max and} the maximum value of the ten data is set as V _O , and the data is not affected by the foam of the washing liquid during this period. If N has not reached 10 in step 108, a delay of T _b (for example, 1 second) and N are incremented by 1 in steps 109 and 110, and the process returns to step 102. FIG. 8 shows the relationship between V _O thus obtained and the individual data strings V ₁ .

Advantageous Effects of the Invention As described above, according to the present invention, the washing or rinsing operation is performed by accurately detecting the change in the turbidity of the washing liquid due to dirt falling from the laundry so as not to be affected by bubbles generated during washing. This can be performed automatically, and the water flow is not weakened, so that there is an effect that no adverse effects such as a decrease in cleaning efficiency are caused.

Furthermore, since a large current can be applied to the light-emitting element instantaneously, even if the inner wall of the detection part becomes dirty, if a large amount of current is applied in accordance with the degree of the contamination, the degree of contamination of the liquid in the water receiving tank will be the same as when there is no contamination. Has the effect that it can be detected with high accuracy.

[Brief description of the drawings]

FIG. 1 is a block diagram of a fully automatic washing machine according to one embodiment of the present invention, FIG. 2 is a cross-sectional view of a fully automatic washing machine according to one embodiment of the present invention, and FIG. FIG. 4 is a circuit diagram of a transmittance detector and a peak hold circuit according to one embodiment of the present invention, FIG. 5 is a timing chart of one embodiment of the present invention, and FIG. FIG. 7 is a flowchart showing one embodiment of the present invention,
FIG. 8 is a characteristic diagram showing one embodiment of the present invention. 2 ... water receiving tank, 13 ... transmittance detector, 22 ... transmittance detector, 23 ... peak hold circuit, 24 ... microcomputer.

Claims (1)

(57) [Claims] 1. A light emitting element and a light receiving element for detecting a degree of contamination of a liquid in a tank, a switching section for turning on and off a current flowing through the light emitting element, and a plurality of times of turning on and off the switching section.
Maximum value detection means for detecting the maximum value of the output of the light receiving element in operation, and control means for controlling at least the washing or rinsing operation with the output of the maximum value detection means as a degree of liquid contamination, Washing machine control device.