KR20040047024A - Washing machine's electrode sensor's error sensing method - Google Patents

Abstract

PURPOSE: A sensing method of a misoperation of an electrode sensor for a washing machine is provided to operate a washing stroke with an additional control program by deciding a misoperation of the electrode sensor when an error is over reference value after comparing last rinsing conductivity with average conductivity. CONSTITUTION: Conductivity of washing water in the last rinsing operation is sensed(S2,S3). Whether an electrode sensor is in normal condition or abnormal condition is decided according to difference value between measured conductivity and average conductivity(S7,S8,S9,S12). The rest strokes are operated by a specific control program independent from sensed conductivity when the electrode sensor is in abnormal condition(S10,S11). Thereby, unnecessary operation and waste of energy are prevented by controlling the washing stroke when the electrode sensor is in abnormal condition.

Description

Washing machine's electrode sensor's error sensing method

The present invention relates to a method of detecting a malfunction of a washing machine electrode sensor, in particular, obtaining an average conductivity from accumulated conductivity, and determining a malfunction of the electrode sensor when the difference value detected during the final rinse of the average conductivity and each time exceeds a predetermined value. The present invention relates to a method of detecting a malfunction of a washing machine electrode sensor, which can guarantee a result of sensing the electrode sensor and the reliability of the washing stroke according to the control of the stroke by operating a separate control program to compensate for this.

1 is a cross-sectional view showing the structure of a general washing machine, with reference to this will be described the structure of the washing machine.

In general, a fully automatic washing machine is a device in which all operations of washing, rinsing, and dehydration are performed in one washing tank, and automatic water supply and drainage operations necessary for the input and switching of detergent are performed. The inner tank (1) and the outer tank (2) And a washing tank 10 equipped with a pulsator, a water supply and drain valve 30 for supplying and draining the washing water, a driving motor 40 for driving the washing tank 10, and It comprises a variety of sensing means 20, and a microcomputer (not shown) for programming the amount of detergent or washing pattern according to the signal output by the sensing means 20, and controls the operation of the washing machine.

The sensing means 20 applied in the washing machine is different depending on the model, but is composed of a water level sensor for detecting the level of the wash water, a temperature sensor for detecting the temperature of the wash water, an electrode sensor for measuring the conductivity of the wash water, etc. Bar, the microcomputer receiving the value sensed through the sensor is combined and converted to determine the washing pattern.

In particular, the microcomputer detects the hardness of the wash water according to temperature and conductivity by operating a temperature sensor and an electrode sensor to grasp the water quality of the wash water. The conductivity is an inverse of the electrical resistance of a solution existing between two equilibrium electrodes. Is defined. The electric flow in the wash water increases in conductivity as the amount of ions in the wash water increases, and as the concentration of the wash water increases. Therefore, by measuring the conductivity it is possible to determine the change in the amount of ions contained in the wash water.

Such an electrode sensor detects conductivity according to a current flowing through a low alternating voltage between two electrodes. When the electrode sensor is used for a long time, metal ions in the wash water precipitate and scale between the two electrodes to actually wash. Unnecessary washing strokes can be performed as the conductivity of the water and different conductivity are sensed, and there is also a problem of lowering the efficiency of washing and rinsing strokes.

The present invention has been made to solve the above problems of the prior art, the object of which is to compare the average conductivity and the conductivity at the time of the final rinse to determine whether the electrode sensor is normal or abnormal detection, the error is a reference value If it is abnormal, it is determined that the electrode sensor is malfunctioning, and the washing stroke is performed by a separate control program to prevent unnecessary operation due to the electrode sensor malfunction and energy waste, and to ensure the stability and reliability of the washing efficiency. The present invention provides a method of detecting a malfunction of a washing machine electrode sensor.

1 is a cross-sectional view showing the structure of a general washing machine;

2 is a flow chart showing the flow of the malfunction detection method of the washing machine electrode sensor of the present invention.

<Explanation of symbols on main parts of the drawings>

1: innermost 2: outermost

10: washing tank 20: detection means

30: drain valve 40: drive motor

According to a feature of the malfunction detection method of the washing machine electrode sensor according to the present invention for solving the above problems, the first step of detecting the conductivity of the wash water during the final rinsing, the conductivity of the first step and the predetermined average conductivity A second step of determining a normal detection state or an abnormal detection state of the electrode sensor according to the difference value, and a specific control program independent of the conductivity detected in the first step if the detection state is abnormal according to the result of the second step. And a third step of performing the remaining stroke.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. 2 is a flow chart showing the flow of the malfunction detection method of the washing machine electrode sensor of the present invention.

After the detergent is added, the washing stroke S1 and the rinsing stroke are performed (S2).

The rinsing stroke is performed a number of times depending on the degree of contamination of the laundry. Therefore, the microcomputer that controls the general matters of the washing machine can determine the water quality state by detecting the conductivity after the final rinsing stroke through an electrode sensor that detects the conductivity of the washing water (S3).

However, a metal ion containing washing water may be deposited and attached between both electrodes of the electrode sensor as the electrode sensor is used for a long time, so the detection result of the electrode sensor may have a different value from the actual conductivity. In contrast, during the set number of times of use (S4), the conductivity during final rinsing is accumulated (S5) to obtain an average conductivity (S6). The average conductivity is a value obtained by dividing the sum of the accumulated conductivity by a set number of uses, and means an average value of the conductivity detected after the final rinse per one time.

The set number of times of use can be changed according to the producer, but the higher the number of times of use, the higher the reliability of the average value is. Therefore, several tens of times is preferable.

Each time the washing machine is used, the difference value of the conductivity is obtained by subtracting the average value from the conductivity detected by the electrode sensor during the final rinsing (S7). Since the difference is larger than the average conductivity, it means that the difference is greater than the reference value (S8), it is determined that the electrode sensor is abnormally detected (S12). The reference value is a limit value of the error range.

The abnormal detection state of the electrode sensor is a state in which the reliability of the detection result is lowered due to a malfunction of foreign matter or scales deposited on the electrode of the electrode sensor, so that the detection result is added by a compensation program preset in the microcomputer separately from the detection result by the electrode sensor. The rinsing and dehydration stroke is controlled (S13), and if the difference is less than the reference value, the electrode sensor is determined to be in a normal sensing state (S9) and controlled by a standard program (S10).

The remaining stroke is performed as controlled (S11), and washing is completed.

In the malfunction detection method of the washing machine electrode sensor of the present invention configured as described above, if the difference between the conductivity and the average conductivity at the time of the final rinse is greater than or equal to the reference value, it is determined that the electrode sensor is abnormally detected and the washing stroke is performed according to a separate washing program. By controlling it, it is possible to prevent unnecessary operation due to the abnormality of the electrode sensor and thereby waste of energy, to ensure the stability and reliability of the washing efficiency, and to improve the convenience of using a washing machine.

Claims (4)

A first step of detecting the conductivity of the wash water in the final rinse, and a second step of determining the normal or abnormal detection state of the electrode sensor according to the difference between the conductivity of the first step and the predetermined average conductivity, And detecting a malfunction of the washing machine electrode sensor, when the abnormal state is detected according to the result of the second step, a remaining step is performed by a specific control program independent of the conductivity detected in the first step. Way. The method of claim 1, The average conductivity of the first step is a malfunction of the washing machine electrode sensor, characterized in that the sum of the accumulated conductivity detected by the electrode sensor during the final rinse for a predetermined number of times of use from the beginning of the purchase divided by the number of times of use Detection method. The method of claim 2, The average conductivity is a malfunction detection method of the washing machine electrode sensor, characterized in that stored in the EEPROM (EEPROM). The method of claim 1, The second step may include a first process of obtaining a difference value by subtracting the average conductivity from a sensed conductivity, a second process of comparing whether the difference value exceeds an error tolerance range, and the difference value determines the error tolerance range. And determining the electrode sensor as an abnormal detection state when exceeding, and determining the electrode sensor as a normal detection state when it is less than the allowable error range.