JPS6247559B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to detecting the end of spin-drying in a washing machine using a photocoupler.

In conventional washing machines, spin-drying is done either by running the machine for a fixed period of time using a time switch, or by determining the spin-drying time based on the amount and type of laundry being carried by the user. There was a drawback that dehydration could not be carried out according to the type.

In order to eliminate this drawback, a light-emitting element and a light-receiving element are installed in the drainage path formed between the bottom of the outer tub of the washing machine and the drain valve. It has been proposed to detect the end of dehydration by detecting the resulting change in light transmittance.

However, since the drainage path in which the detection unit is located is located at the bottom of the washing machine, for example, when the washing machine is installed in a bathroom, the drainage hose may cross the threshold of the bathroom. In this case, the part where the drain hose crosses the threshold may be located higher than the detection part at the bottom of the washing machine, and in such cases water will always accumulate in the detection part, causing changes in light transmittance. There was an undetectable flaw.

The present invention eliminates the drawbacks of the conventional method by preventing insufficient dehydration from occurring even when it is no longer possible to accurately detect the end of dehydration.

An embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

In FIG. 1 showing the general structure of a washing machine, 1 is the main body of the washing machine, 2 is an outer tank suspended from the main body 1 by a suspension 3, 4 is an inner tank for washing and dewatering clothes, and 4 is an inner tank for washing and dehydrating clothes. It has a large number of through holes 5. 6 is a pulsator that stirs the clothes in the inner tank 4;
7 is a mechanical case with a built-in brake/clutch mechanism; 8 is a motor that rotates forward and reverse during washing and rinsing; it is attached to the bottom of the outer tub 2; it rotates the inner tub 4 during spin-drying; rotates the pulsator 6. 9 is a drain valve that is closed during washing, rinsing, and water supply; 10 is a drain path formed between the drain valve 9 and the bottom of the outer tank 2; 11
is a drain hose connected to the drain valve 9, and 12 is a detector attached to the drain path 10.

As shown in FIG. 2, the detector 12 has a light emitting element 13 made of an infrared light emitting diode and a light receiving element 14 made of a phototransistor facing each other.
A drainage path 10 is located between the two to allow the dehydration liquid to freely pass through. In FIG. 1, 15 is a dewatering shaft to which the inner tank 4 is fixed.

Next, its operation will be explained. In the dehydration process, the inner tank 4 rotates around the dehydration shaft 15,
The water that has soaked into the clothes in the inner tub 4 is centrifuged and discharged to the outside of the washing machine through a drainage path 10 and a drainage hose 11.

Now, when a detector 12 consisting of a light emitting element 13 and a light receiving element 14 is attached to the drainage path 10, the rinsing liquid is almost transparent at the time of drainage, so the light transmittance is high, but in the initial stage of dehydration, Since the clothes in the inner tank 4 contain a large amount of moisture, the amount of water flowing through the drainage path 10 is large.
Moreover, since a large amount of bubbles are generated during the dehydration process, a large amount of light emitted from the light emitting element 13 of the detector 12 is blocked, resulting in poor light transmittance. However, as dehydration progresses, the amount of moisture contained in the clothes decreases, and as the amount of water passing through the drainage path 10 decreases, the amount of light emitted from the light emitting element 13 is blocked, so the light Transmittance improves.

In conventional washing machines, changes in light transmittance are detected in this manner, and the spin-drying time is controlled so that spin-drying ends when the transmittance becomes stable.

However, the drainage route 10 equipped with the detector 12
is located at the bottom of the outer tank 2, and as shown in FIG. 4, the drain hose 11 may become clogged with lint 16, or as shown in FIG.
In some cases, there was a portion located above the detector 12, exceeding the detector 12.

In these cases, the water dehydrated from the clothes stagnates or remains in the detector 12, and the light transmittance does not change as shown by characteristic line B in FIG. 3 even as dehydration progresses. In other words, the transmittance does not change even though the water contained in the clothing is separated.

In this case, the detector 12 detects that the transmittance has stabilized, but there is a drawback that the dehydration ends in a state where the dehydration is insufficient.

If the drainage hose is located higher than the detector installation position, or if the drainage hose is clogged and the drainage condition worsens, the transmittance will change as shown in graph B in Figure 3. For example, the transmittance is detected after a certain period of time has elapsed from the start of dehydration (T ₁ in Figure 3), and the value is determined to be a constant reference value, that is, a value set lower than the value at which the light transmittance is stable during normal dehydration. If the condition is above (a) in Figure 3, it can be determined that any part of the drain hose is at a lower position than the detector, or that the drain hose is not clogged. If the value is less than a certain reference value a, it can be determined that the middle of the drain hose is located at a higher position than the detector, or that the drain hose is clogged. The reference value can be determined experimentally.

The present invention detects the light transmittance in the drainage path after a certain period of time has elapsed from the start of dewatering, and if this value exceeds a reference value, the dewatering operation continues and the dewatering starts when the change in light transmittance stabilizes. When the above-mentioned value is below the reference value, the dehydration operation is continued for a certain period of time, thereby eliminating insufficient dehydration and eliminating the above-mentioned drawbacks of the conventional method.

Examples thereof will be described in detail below.

When the detector 12 and the drain hose 11 are at the same height, the transmittance shown after a certain time T ₁ has elapsed since the start of dehydration is determined as α, and then in the actual dewatering operation, the transmittance shown after a certain time T ₁ has elapsed since the start of dewatering. If the transmittance detected later is larger than this α, dehydration will continue and the dehydration will be terminated when the change in light transmittance stabilizes, and if it is below this α, the dehydration operation will continue for a certain period of time. Configure the program accordingly.

The operation of the fully automatic washing machine shown in FIG. 1 to which the above set specifications and program are applied is as follows.

A light-emitting element 13 and a light-receiving element 14 detect the change in light transmittance during dehydration and detect the end of dehydration.
A detector 12 consisting of the following is installed in the drain path 10 formed between the bottom of the outer tub 2 of the washing machine and the drain valve 9, and a detector 12 is installed in the drain path 10 formed between the bottom of the outer tub ₂ of the washing machine and the drain valve 9.
If the transmittance of the light emitted from the light emitting element 13 in is equal to or higher than the reference value α, that is, if the drain hose 11 is at a lower position than the height of the detector 12, or if the drain hose is not clogged, the dewatering starts at a certain level. Since the transmittance after the elapse of time T ₁ exceeds the reference value, dehydration is subsequently performed, and the dehydration is terminated when the change in light transmittance becomes stable. However, if the drainage hose 11 is located at a higher position than the detector 12 even if only partially, or if the drainage hose 11 is clogged and the drainage condition is poor, the dewatering start period will be delayed.
Since the transmittance after T ₁ has elapsed is below the reference value, the dehydration operation is subsequently performed for a certain period of time according to the program, and a dehydration state equivalent to the normal dehydration time can be obtained. In this case, an abnormality has occurred, such as the drain hose 11 being clogged or the drainage condition being poor, so a light emitting diode may be turned on or blinking to notify this, or a buzzer may be sounded. can.

As described above, the present invention allows dewatering to continue for a certain period of time if the light transmittance in the drainage path after a certain period of time has elapsed since the start of dehydration is less than the standard value, thereby preventing the problem from occurring in abnormal cases where the drainage condition is poor. This is of great industrial value as it solves the problem of dehydration.

[Brief explanation of the drawing]

Fig. 1 is a side sectional view of a fully automatic washing machine, Fig. 2 is a sectional view of a detector in the washing machine, Fig. 3 is a change diagram of the light transmittance of the detector during the dehydration process of the washing machine, and Fig. FIG. 4 and FIG. 5 are explanatory diagrams of an abnormal state of drainage in the washing machine. 10...Drainage route, 11...Drainage hose, 12
……Detector.

Claims (1)

[Claims] 1 After a certain period of time has elapsed since the start of dewatering, the light transmittance in the drainage path is detected, and if this value exceeds the standard set value, the dewatering operation is continued and the dewatering is terminated when the change in light transmittance stabilizes. If the value is below the reference value, the washing machine is operated for a certain period of time, and the reference value is set to be lower than the light transmittance at the time when the change in light transmittance stabilizes during normal dehydration. .