JPS6216120B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a process end detection device for a washing machine that detects the end of processes such as washing, rinsing, and draining.

Conventionally, automatic washing machines, such as fully automatic washing machines that automatically carry out each process such as washing, rinsing, draining and dehydrating, have either been controlled by a time switch for a certain period of time, or
Alternatively, when it comes to washing only, the user judges the amount of laundry, how dirty it is, etc., and sets the time switch appropriately. This makes it difficult to wash, rinse, and dehydrate the laundry according to the amount and dirtiness of the laundry.

Therefore, a detector consisting of a light-emitting element and a light-receiving element is installed at the bottom of the washing tub, and in the middle of the drainage path,
By detecting changes in light transmittance through the liquid,
A method was devised to detect the end of each process of washing, rinsing, draining, and spin-drying.

However, washing machines are often used in humid places such as bathrooms, and as a result, condensation forms on the surfaces of the light-emitting element and light-receiving element, which are the transmittance detection elements, and this causes the transmittance to be distorted. However, there is a problem in that the end point of each process cannot be accurately detected in some cases.

The present invention solves the above-mentioned conventional problems, and embodiments thereof will be described below with reference to the accompanying drawings.

Note that the present invention is not limited to implementation in a fully automatic washing machine that includes dehydration, but in a two-tub type washing machine in which dehydration is performed in the dehydration tank, each process such as washing, rinsing, and draining is carried out in the washing tank. It can be implemented in the same way even if the method is to be carried out.

An object of the present invention is to prevent dew condensation on the detection element and maintain stable detection accuracy in a detector that detects the end of each cycle of the washing machine and controls the operation of the washing machine. be.

In the figure, 1 is the main body of the washing machine, 2 is an outer tub suspended and supported by a suspension 3, and 4 is an inner tub for washing clothes, which has a large number of holes 5 in the wall surface. A pulsator 6 stirs the clothes in the inner tank 4. 7 is a mechanical case with a built-in brake/clutch mechanism; 8 is a motor; during washing and rinsing, the pulsator 6 is rotated through the clutch mechanism; during washing and rinsing, the pulsator 6 is rotated; The tank 4 is rotated for dehydration in one direction. 9 is a drain valve, which is closed during each process of washing, rinsing, and supplying water. A drainage path 10 made of a tubular translucent material is formed to communicate between the drainage valve 9 and the inner bottom of the outer tank 2.
11 is a drain hose connected to the drain valve 9.

Reference numeral 12 is a detector provided in the middle of the drainage path 10, which is composed of a light emitting element 13 and a light receiving element 14, which are provided facing each other, and the drainage path 10 is interposed between these elements 13 and 14. The detector 12 has a holder 12a that is detachably attached to the drain valve 9, and a light emitting element 13 made of, for example, a light emitting diode and a phototransistor, etc. The light-receiving elements 14 are respectively mounted, and after mounting, the light-receiving elements 14 are sealed by coating. On the inner surface of the holder 12a, there is formed a projecting wall 12c whose tip corresponds to the recess 12b and has a flat surface.

Although the drainage path 10 is tubular, it has a protruding wall 12c.
There is a flat surface 10 on a part of the outer surface corresponding to the flat surface of
a is formed, and a protruding wall 1 is formed on this flat surface 10a.
The tips of 2c are in close contact with each other in surface contact.

The entire holder 12a or a portion corresponding to the protruding wall 12c is made of a light-transmitting material,
When transmitting light in the infrared region, it does not need to be transparent, and may be made of polypropylene, for example.

In the above configuration, at the end of each process such as washing, rinsing, draining, and dehydrating, the light emitted from the light emitting element 13 passes through the drainage path 10 to detect changes in the turbidity of the washing liquid, rinsing liquid, etc. in the drainage path 10. The ratio of the amount of light reaching the light-receiving element 14, that is, converted into light transmittance, is detected, and the ratio of change is used for detection. Similarly, in each process of drainage and dewatering, the end time is detected by detecting a change in the light transmittance of the drainage path 10.

If water droplets form on the front side of the light-emitting element 13 and the light-receiving element 14 or dust adheres to them,
The light transmittance deteriorates, and when detecting the end of each process, a malfunction may occur or the detection accuracy may become low. However, as in the above embodiment, the front sides of the light emitting element 13 and the light receiving element 14 and the outer surface of the drainage path 10 are in close contact with each other in a state of face-to-face contact. Then, the end of each process such as washing, rinsing, draining, and dehydration can be detected stably over a long period of time without any malfunction.

In addition, in the example, a flat surface was provided on the drainage route side,
Although we have described the case where the protruding wall is brought into close contact with the projecting wall in surface contact, it is also possible to directly bring the front surfaces of the light emitting element and the light receiving element into close contact with each other in surface contact without using the projecting wall. The protruding wall may be brought into surface contact with the protruding wall in a curved state while remaining in the curved state. Further, the drainage path may be formed of a material, such as polypropylene, which can transmit light in the infrared region like the holder.

As is clear from the above embodiments, according to the present invention, by providing the light emitting element and the light receiving element in a detachable holder that covers the drainage path, the optical axis of the light emitting element and the light receiving element can be set in the detection unit alone. This improves detection accuracy and facilitates repair work. Furthermore, even if the detector is configured to be detachable, the front sides of the light-emitting element and light-receiving element of the detector are in close surface contact with the outer surface of the drainage path, so condensation or dirt can form between them. The detection accuracy can be stably maintained over a long period of time, and the end of the stroke can be reliably detected. Furthermore, due to the close contact between the front side of the light receiving element and the drainage path, it is possible to prevent external light from entering between the two, thereby significantly improving accuracy.

[Brief explanation of the drawing]

FIG. 1 is a schematic longitudinal cross-sectional view of a washing machine showing an embodiment of the present invention, and FIG. 2 is a cross-sectional view showing the state in which a detector is attached to a drainage path. 10... Drainage route, 12... Detector, 13...
Light emitting element, 14... Light receiving element, 10a... Flat surface.

Claims (1)

[Claims] 1. A detector is provided to detect the end of washing, rinsing, draining, etc. processes, and a tubular drainage path made of a translucent material is provided to communicate between the bottom of the tank and the drain valve. , the detector covers a part of the drainage path and is configured with a light-emitting element and a light-receiving element facing each other through the drainage path in a removable holder, with the front side of the light-emitting element and the light-receiving element facing each other through the drainage path. ,
A cycle end detection device for a washing machine that is brought into direct or indirect contact with the outer surface of the drainage path. 2. The cycle end detection device for a washing machine according to claim 1, wherein the drainage path has a flat surface on a part of its outer surface that brings the light emitting element and the light receiving element into surface contact.