JP2967419B2 - Washing machine - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a washing machine that controls a washing operation by detecting a change in turbidity of a liquid in a tub.

2. Description of the Related Art Conventionally, there has been proposed a method of detecting the turbidity of a washing liquid using a light emitting element and a light receiving element and setting a washing time and a rinsing time according to the turbidity. A reference value was set under a fresh water rate of 100%, and the turbidity during washing and rinsing was detected based on the reference value.

However, in such a conventional configuration, however, the washing operation is actually performed once, and the turbidity reference value at the time of fresh water is set only after the rinsing process. The reference value of the turbidity was unstable, and there was a problem that appropriate washing control could not be performed.

In view of the above problems, it is a first object of the present invention to be able to easily set a turbidity reference value in a short time by a specific switch operation without actually performing a washing operation. The second object is to set the output of the light receiving element of the turbidity detector to a reference value beforehand at the time of shipment from the factory and store the output level control data of the light emitting element at that time in a memory.
An object of the present invention is to make it possible to detect turbidity based on a rate of change from a reference value of turbidity at the time of fresh water from the first washing operation, and to perform optimal washing and rinsing control.

Means for Solving the Problems To achieve the above object, the present invention provides a turbidity detector comprising a light emitting element and a light receiving element, which detects turbidity of the washing liquid,
A current control circuit for causing a current to flow through the light emitting element, and a voltage conversion circuit for extracting an output signal of the light receiving element,
An A / D input unit for inputting a PWM output signal that is an input of the current control circuit and an output voltage of the voltage conversion circuit,
Washing, rinsing, control means having a setting switch signal input section necessary for setting at the time of dehydration operation, and storage means, wherein the control means receives the light when the specific switch is operated by the setting switch. Controlling the current of the light emitting element by the PWM output signal so that the output voltage of the element falls within the reference voltage range, and storing the PWM output signal at this time as current setting control data of the light emitting element in the storage means. It is.

According to the first technical means, since the output of the light receiving element of the turbidity detector is controlled to the reference value by operating a specific switch, the turbidity can be easily and quickly reduced without actually performing the washing operation. The reference value of can be set.

According to the second technical means, the output of the light receiving element of the turbidity detector is set to a reference value in advance at the time of factory shipment,
Since the output level control data of the light receiving element at that time is stored in the memory, when the laundry is actually washed at home,
The light-receiving element current is controlled by the control data stored in the memory from the first washing operation, and the optimum washing and rinsing control can be performed by changing the turbidity from that value as a constant value.

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 2 shows the overall configuration of the washing machine. In FIG. 2, reference numeral 1 denotes a washing machine main body, and 2 denotes an outer tub, which is suspended and supported in the washing machine main body 1 by four rods 3 and has a vibration-proof structure. Reference numeral 4 denotes a washing tub having a large number of holes in the wall surface and also serving as a dehydration tub. 5 is a pulsator that rotates normally and reversely.
The clothes inside are to be washed. 6 is a motor, 8 is a drain valve, and 9 is a drain hose. FIG. 1 shows an electric circuit configuration of the washing machine. As shown in FIG. 1, the turbidity detector 7 is provided in the middle of the drainage path 19, and includes a light emitting element 7a and a light receiving element 7b provided to face each other. These two elements 7a,
The drainage path 19 is interposed between 7b.

The control means 10 is a microcomputer, which is a control means of a fully automatic washing machine for controlling a series of washing operations of washing, rinsing and dehydration, and outputs a pulse as an output terminal thereof, and a duty ratio of the pulse can be changed. It has a suitable pulse output terminal (PWM terminal).

A D / A circuit 11a that receives the PWM signal and performs D / A conversion, and a constant current circuit 11b that receives an output voltage of the D / A circuit 11a and supplies a constant current corresponding to the voltage value to the light emitting element 7a. The D / A circuit 11a and the constant current circuit 11b constitute a current control circuit 11 that linearly changes the control current to the light emitting element 7a. The voltage conversion circuit 12 converts the output signal of the light receiving element 7b into a voltage, and the output voltage is input to the A / D input terminal of the control means 10. The current control circuit 11 and the voltage conversion circuit 12 constitute a reference voltage control means 13.

The setting switch input means 14 is a switch necessary for setting at the time of washing, rinsing and dehydrating operations. As shown in the operation panel of FIG. 3, the water level switch 20, the water flow switch 21,
Washing time changeover switch 22, rinse changeover switch 23, dehydration time changeover switch 24, clock switch 25, hour switch 26, minute switch 27, reservation switch 28 and large course switch 29,
Hand wash course switch 30, speedy course switch 31,
It comprises a bio-rough course switch 32, a sensor bio-course switch 33, a sensor course switch 34, and a start / pause switch 35. The power switch input means 15 supplies power to the control means 10 and the load /
This is a switch to cut off. The display means 16 displays the contents set by the setting switch input means 14, and includes a water level display 40, a water flow display 41, a washing time display 42, a rinsing display 43, a dehydration time display 44, a clock display 45, and a sensor. It comprises a monitor display section 46, a travel progress display 47, and a course setting display 48. Buzzer notification means 17 is setting switch input means
It is a notification means in various cases, such as at the time of input by 14 or at the end of washing, and is constituted by a buzzer. The storage means 18 is a memory for storing output level control data of the light emitting element when the output of the light receiving element 7b of the turbidity detector 7 is set to a reference value. You are using memory.

As shown in FIG. 4, the output signal waveform of the PWM terminal of the control means 10 has a constant synchronization T and a high-level pulse width t _H.
Changes, the duty ratio changes. The output signal of this PWM terminal is connected to the D / A circuit 11a and the constant current circuit 1
The control current of the light emitting element 7a is controlled by the current control circuit 11 comprising 1b.
Linearly varied to indicate I _F in FIG. 5. Resolution of the control current I _F is set to 2 ⁸ = 256, and 100 ^mA / 2 ⁸ ≒ 0.4 ^mA and the maximum value of I _F and 100 ^mA.

The transfer characteristics of the turbidity detector 7 composed of the light emitting element 7a and the light receiving element 7b include those having good transfer characteristics and those having bad transfer characteristics as shown in FIG. Further, it is considered that the transfer characteristic is equivalently deteriorated because the drainage path 19 becomes dirty as the washing machine is used.

Here, the control means 10 is, by a specific operation in the setting switch input means 14 and the power switch input means 15,
Through a voltage conversion circuit 12 the output signal of the light receiving element 7b of the turbidity detector 7 and input to the A / D input terminal, the control current I _F of the light emitting element 7a as the input voltage V _O becomes a predetermined value decide.
Here, the specific switch operation is different from the normal switch operation for the washing operation.In this embodiment, the power switch 15 is turned on while simultaneously pressing the water level switch 20 and the water flow switch 21, and thereafter, The operation of pressing the water level changeover switch 20 again is a specific operation.

The output level control data of the light emitting element 7a when the output of the light receiving element 7b of the turbidity detector 7 is set to the reference value is stored in advance in the storage means 18 at the time of shipment from the factory, and the laundry is actually washed at home. At the time, from the time of the first washing operation, the light emitting element current is controlled by the control data stored in the storage means 18, and the washing and rinsing control is optimally performed by changing the turbidity from that value to a constant value.

The control current I _F of the light emitting element 7a where such control means 10 becomes the output voltage V _O of the light receiving element 7b of turbidity detector 7 with the reference value V _A
The method of determining the control data and the process until the control data is stored in the storage means 18 will be described with reference to FIGS. The control means 10 first determines whether or not a specific switch has been input (step 50).
Next, it is determined whether or not the water above the minimum water level is put in the washing tub 4 (step 51).
First, a small current of 5 ^mA is applied to the light emitting element 7a (step 5).
2), and inputs the output voltage V _O of the light receiving element 7b of the time from the A / D input (Step 53). At this time, consider the case where V _O = 1.5 ^V if the transfer characteristic of the turbidity detector 7 is good, and V _O = 0.5 ^V if the transfer characteristic is poor, as shown in FIG. However, it goes without saying that the transfer characteristics of the turbidity detector 7 include not only these two cases but also an infinite number of combinations. Next, the control unit 10 based on FIG. 7 of the V _O and I _F table is a memory in advance in the internal ROM according to this first output voltage V _O, then flows to the light-emitting element 7a turbidity detector 7 The control current _IF is determined (step 54).

That V _O = 0.5 when ^V then flow I _F and 30 ^mA (step 55) is for the I _F and 10 ^mA when V _O = 1.5 ^V. Light-receiving element 7b when and flushed with I _F based on FIG. 7
The inputs the output voltage V _O again (step 56), ends the V _O is determined whether within a predetermined range (step 57), the current setting of the light-emitting element 7a turbidity detector 7 if within a predetermined range And
The current setting control data is stored in the storage means 18 (step 58), and the buzzer notification means 17 notifies completion. In this embodiment, the buzzer sounds four times here,
The notification is made separately from other notifications (step 59). If V _O is less than the predetermined range (step 60), the light emitting device
Increasing the current I _F of 7a (step 61), inputs the output voltage V _O of the light receiving element 7b of turbidity detector 7 (step 56), it is determined whether or reaches a predetermined value (step 57).

Also if V _O is greater than a predetermined range (step 60), then decrease the current I _F of the light emitting element 7a (step 62), again the output voltage
_VO is input (step 56), and it is determined whether or not a predetermined value has been reached (step 57).

Effects of the Invention As is clear from the above embodiments, the present invention controls the output of the light receiving element of the turbidity detector to a reference value by operating a specific switch, so that the output can be easily performed without actually performing a washing operation. The reference value of turbidity can be set in a short time in a short time, and in the case of service correspondence, even if parts such as a printed circuit board are replaced, it can be quickly handled.

Also, since the present invention sets the output of the light receiving element of the turbidity detector to a reference value in advance at the time of shipment from the factory and stores the output level control data of the light emitting element at that time in the memory, Since the light emitting element current can be controlled by the control data set at the time of fresh water stored in the memory from the first washing operation, the optimum washing can be performed by the turbidity change from that value without being affected by the detergent or the like.
The effect that rinsing control can be performed is obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a control device of a washing machine in one embodiment of the present invention, FIG. 2 is a sectional view of the washing machine, FIG. 3 is a diagram showing an operation panel of the washing machine, and FIG. FIG. 5 is a diagram showing a pulse output signal of the control device, FIG. 5 is a diagram showing a high level width t _H of the pulse signal of the control device and a current characteristic of the light emitting element, and FIG. 6 is a transmission of a turbidity detector of the control device. FIG. 7 is a diagram showing characteristics, FIG. 7 is a diagram showing the contents of a ROM stored in advance in the control device, and FIG. 8 is a flowchart of the control device. 7 turbidity detector, 10 control means, 11 current control circuit, 12 voltage conversion circuit, 13 reference voltage conversion means, 14
... setting switch input means, 15 ... power switch input means, 16 ... display means, 17 ... buzzer notification means, 18 ... storage means, 19 ... drainage path.

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Sadayuki Tamae 1006 Kazuma Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. In company

Claims (1)

(57) [Claims] 1. A turbidity detector comprising a light emitting element and a light receiving element for detecting turbidity of a washing liquid, a current control circuit for supplying a current to the light emitting element, and extracting an output signal of the light receiving element. A voltage conversion circuit, an A / D input unit for inputting a PWM output signal which is an input of the current control circuit and an output voltage of the voltage conversion circuit, and a setting switch signal required for setting at the time of washing, rinsing and dehydrating operations Control means having an input unit, and storage means, wherein the control means is such that, when a specific switch operation is performed by the setting switch, the output voltage of the light receiving element is in a reference voltage range.
A washing machine that controls a current of a light emitting element by a PWM output signal, and stores the PWM output signal at this time as current setting control data of the light emitting element in the storage unit.