JPH04240485A - Turbidity detector for washing machine - Google Patents

Abstract

PURPOSE:To provide a turbidity detecting device for a drum type washing machine which can detect turbidity accurately by eliminating error eous detection accompanying difference in the density due to stagnation of cleanser irrespective of the amount of cleanser and circulating and dispersing washing liquid uniformly. CONSTITUTION:A circulation path 11 is provided outside a tank 12 and has a protruding auxiliary tank 13, a part of which is made to be semi-transparent. The semi-transparent part of the auxiliary tank 13 is equipped with a turbidity sensor 10, which consists of a light emitting element and a light receiving element opposed to each other and outputs signals to a control means. If a drum 14 is rotated clock wise for washing, water stream in the circulation path 11 flows in direction A, while if the drum 14 is rotated counter clock wise, the water stream flows in direction B, whereby stagnation of washing liquid at the turbidity sensor 10 part is eliminated by circulation.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a turbidity detection device for a washing machine that controls washing operation according to the degree of dirtiness of laundry.

0002

2. Description of the Related Art A conventional turbidity detection device for a washing machine of this type has a configuration as shown in FIG. In the figure, 1 is a turbidity sensor that detects the degree of dirt with a light-emitting element and a light-receiving element arranged facing each other, 2 is a drain port, which connects the bottom of a tank 3 to a drainage means 4, and a part of it is semi-transparent. turbidity sensor 1 is installed. Reference numeral 5 denotes a control means for controlling the drainage means 4, the water supply means 6, the stirring means 7, and the like. In the above configuration, the turbidity sensor 1 determines the amount of dirt in the washing liquid accumulated in the drain port 2 and inputs the result to the control means 5 to control the washing time.

0003

[Problems to be Solved by the Invention] However, when the conventional turbidity detection device for a washing machine described above is used in a drum-type washing machine that uses a small amount of washing liquid and a large amount of detergent, when the drum is rotated with a small amount of washing liquid, There was a problem in that water movement became very slow, detergent and dirt accumulated at the bottom of the tank 3, and the concentration of the detergent solution increased only in that part.

[0004] This method solves the above-mentioned conventional problem, and aims to match the concentration of the washing liquid in the tank and in the turbidity sensor.

[0005]

[Means for Solving the Problems] In order to achieve the above-mentioned conventional objects, the present invention provides a water supply means for supplying water into a tank, an agitation means for agitating the laundry, and a system for detecting dirt in the washing liquid. A turbidity sensor and a control means for controlling the water supply means and the agitation means to perform washing according to an output signal from the turbidity sensor, a circulation path having a translucent part provided outside the tank, A turbidity sensor is attached to the semi-transparent part.

[0006]

[Function] With the above configuration, the detergent liquid circulates through the circulation path, so the concentration of the washing liquid inside the drum and in the circulation path becomes uniform, without the laundry liquid having a high concentration of dirt accumulating at the bottom of the tank, and the turbidity sensor accurately detects the washing liquid. It can be determined and over-washing can be prevented.

[0007]

[Example] An example of the present invention will be described below with reference to FIGS. 1 to 4.
This will be explained with reference to. In the figure, 10 is a turbidity sensor that detects dirt with a light-emitting element and a light-receiving element arranged facing each other, 11 is a circulation path, which is connected to two places in the tank 12, and an auxiliary tank 13 is attached to it. 1
The turbidity sensor 10 is attached by making a part of the turbidity sensor 3 semi-transparent. 14 is a drum rotatably provided within the tank 12.

To explain the operation, when the drum 14 rotates clockwise in the stirring process, the water flow flows in the direction A, and when it rotates counterclockwise, the water flows in the direction B, so that the inside of the drum 14 and the inside of the circulation path 11 have the same concentration of washing liquid.

FIG. 2 shows another embodiment, in which a circulation path 15 is attached to the drainage path, a part of which is made translucent, and a turbidity sensor 10 is attached. Lint case 16 with a built-in dish-shaped structure that can also remove lint
is connected to the circulation path 15.

[0010] In this operation as well, when the drum 14 rotates clockwise, the water flow flows in the direction A, and when it rotates counterclockwise, the water flow flows in the direction B, so that the concentration of the washing liquid in the drum 14 and in the lint case 16 becomes the same. The configuration when the turbidity sensor 10 having the above configuration is incorporated into a drum type washing machine will be explained using FIGS. 3 and 4. That is, 17 is a control means having a microcomputer etc. for controlling a series of operations of washing, rinsing and dehydration; 18
19 is a water supply means for supplying water into the tank 12; 19 is an agitation means for connecting and stirring the drum 14 in the tank 12 with a belt 20 during the stirring process; 21 is a drainage means for discharging the washing liquid accumulated in the tank 14 to the outside. , 10 is a turbidity sensor attached to the circulation path 11 to detect the degree of contamination of the circulating washing liquid, and 22 is a water level sensor connected to the bottom of the tank 12 with a hose 23 to detect the water level. The signal from the turbidity sensor 10 is inputted to the control means 17, processed by calculation, and sent to the water supply means 18.
, is output to the stirring means 19 and the drainage means 21.

The operation of the drum-type washing machine with the above configuration will be explained based on the flowchart shown in FIG. 5 up to the detection of saturation during the agitation process. When the power is turned on and the program is started, in step 24 the control means 17 operates the water supply means 18 to start water supply. In step 25, water level sensor 2
Water is supplied from signal 2 until the water level reaches a certain level. Next, in steps 26 and 27, the stirring means 19 is controlled while periodically inputting the optical sensor output (hereinafter referred to as sensor voltage) set for fresh water by the turbidity sensor 10 attached to the circulation path 11 to the control means 17. Stir 14. As a result, the washing liquid becomes dirty, a water flow is generated in the circulation path 11, and the sensor voltage begins to decrease. In step 28, it is determined whether the temporal change rate ΔV/Δt of the sensor voltage level (maximum value for each cycle) is less than or equal to the set value. If it is, the process returns to step 26 and is repeated until it becomes less than or equal to the set value. (hereinafter referred to as saturation detection). Next, if saturation is detected, steps 29 and 30
In step 31, the saturation time and saturation sensor voltage level are determined, and in step 31, the washing table shown in Table 1 is used from the sensor voltage level, and the washing time is determined as the sum of the saturation time and the sensor voltage level.

0012

[Table 1]

[0013]

Effects of the Invention As is clear from the description of the embodiments above, the turbidity detection device for a washing machine of the present invention prevents detergent and dirt from stagnating and allows the washing liquid to The washing time can be controlled according to the degree of dirt by accurately detecting the turbidity of the laundry, preventing overwashing, and setting the optimal washing time.

[Brief explanation of the drawing]

FIG. 1: (A) External perspective view of a turbidity detection device for a washing machine in an embodiment of the present invention. (B) Cross-sectional view of the turbidity detection device.

FIG. 2 (A) External perspective view of a turbidity detection device for a washing machine in another embodiment of the present invention (B) A sectional view of the same turbidity detection device

[Figure 3] Cross-sectional view showing the turbidity detection device installed in a drum-type washing machine

[Figure 4] Block diagram of the turbidity detection device in the drum-type washing machine

[Figure 5] Operation flowchart of the drum-type washing machine

[Figure 6
] Cross-sectional view of a washing machine equipped with a conventional turbidity detection device

[Explanation of symbols]

10 Turbidity sensor 11 Circulation route 12 Tank 17 Control means 18 Water supply means 19 Stirring means

Claims (1)

[Claims] [Claim 1] Water supply means for supplying water into a tank;
A stirring means for stirring the laundry, a turbidity sensor for detecting dirt in the washing liquid, and a control means for controlling the water supply means and the stirring means according to an output signal from the turbidity sensor to perform washing, A turbidity detection device, wherein a circulation path having a translucent part is provided outside the tank, and a turbidity sensor is attached to the translucent part.