JPH0795952A - Tableware washing apparatus - Google Patents

Abstract

PURPOSE:To save the water and time by selecting after a prewashing is done a shift to thermal washing by feeding a detergent or a resumption of another prewashing after the drain and supply of the water according to both outputs of a fouling detection means and a water temperature detecting means or the output of the fouling detection means to avoid fouling left. CONSTITUTION:A light emitting element 8 composing a fouling detection means is connected to a microcomputer 10 through a light emitting element control circuit 11 and a photo detector 9 is connected to the microcomputer 10 through a photo detector output processing circuit 12. A pump 3 is connected to the microcomputer 10 through a pump control circuit 13. Then, the pump 3 is rotated to perform a prewashing and then, fouling is measured with fouling detectors 8 and 9 to judge the fouling with the microcomputer 10. When the fouling is smaller than a specified value A, after the drain and supply of the water, the pump is rotated gain to perform the prewashing. When the output of the fouling detector is larger than A, a detergent is fed in stead of the drain of the water and a thermal washing is started. This controls the frequency of the prewashing according to the level of fouling thereby maximizing the effect of the prewashing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dishwasher having a dirt detecting device for detecting the degree of dirt of a cleaning liquid.

[0002]

2. Description of the Related Art The steps of dishwashing in a dishwasher include (a) pre-washing without washing with detergent, (b) heat washing with a washing liquid after the washing, (c) rinsing, and (d) drying. . Although some of the steps (a) are deleted, the target is a dishwasher including the steps (a). In such a dishwasher, as a conventional example in which the degree of contamination of the cleaning liquid is detected by measuring the light transmittance and the process is controlled, for example, JP-A-60-
There is one disclosed in Japanese Patent No. 48724. In this conventional example, as shown in FIG. 9, a part of the wall surface of the water absorption pipe 6 between the water reservoir 2 provided at the bottom of the cleaning chamber 1 and the water absorption port of the nozzle pump 3 has a translucent material 7 It is composed of the water absorption pipe 6
A light emitting element 8 and a light receiving element 9 as a dirt detecting means for detecting a change in the transmittance of the liquid inside are arranged opposite to each other. The nozzle pump 3 sprays water (or cleaning liquid) through the spray arm 4 onto the tableware contained in the tableware basket 5, and washing is performed by this jetting force, and the water after spraying is temporarily stored in the water reservoir 2. The water in the water reservoir 2 is sucked into the nozzle pump 3 again through the water suction pipe 6, and the ejection is repeated. Then, in this dishwasher, as shown in the flowchart of FIG. 10 and the change of the dirt detector output in FIG. 11, water supply and dirt detector initialization (steps 71, 72)
After pre-washing by rotating the pump (step 73), stopping the pump, draining water, supplying water, and introducing detergent (steps 75 to 7).
8) At the time of heating and washing by rotating the heater on pump (step 79) after that, the light transmittance is detected by the dirt detector,
In each step, the detector output decreases and becomes a substantially constant value (steps 74, 82) when the dirt removal ends.
That is, it is determined that the cleaning liquid has reached the limit where the dirt is dissolved or the dirt is completely removed, and it is determined that each step has ended.

[0003]

However, in the conventional dishwasher, when there is a large amount of dirt attached to the dishes, the dirt detector output shows a constant value during pre-washing,
In other words, even if the dirt is at the limit of melting, there are many cases where dirt that can be washed by prewash remains in the tableware or the washing room. In such a case, these stains will be melted into the cleaning liquid in the process of the next heat washing, and the dirt components that should be removed by the detergent will not easily melt,
Contamination of dirt will be caused. On the other hand, even if the amount of dirt is very small and it is possible to heat and wash with the water (or hot water) used at the time of pre-washing, drainage and water supply are repeated, resulting in wasteful use of water and time more than necessary. It was

[0004] Therefore, an object of the present invention is to provide a dishwasher capable of avoiding residual stains and saving water and time.

[0005]

In order to solve the above-mentioned problems, a first aspect of the present invention is a dishwasher having dirt detecting means for detecting the degree of dirt of a cleaning liquid and water temperature detecting means for detecting the temperature of the cleaning liquid. Therefore, after the pre-washing step, depending on either the output of the dirt detecting means and the water temperature detecting means or the output of the dirt detecting means during the pre-washing step,
The gist of the present invention is to have a control means for selecting whether to put the detergent into the heating washing step or to perform the pre-washing step after draining and supplying water.

Secondly, there is provided a dishwasher having a dirt detecting means for detecting the degree of dirt of the cleaning liquid and a water temperature detecting means for detecting the temperature of the cleaning liquid, wherein the dirt detecting means and the water temperature detecting means in the pre-washing process. After the pre-washing step according to either of the outputs of the above or the output of the stain detecting means,
It has a control means for selecting whether to add a detergent to the pre-washing solution to shift to the heating washing step or to drain water and supply water and then add the detergent to shift to the heating washing step. To do.

[0007]

In the above structure, firstly, it is determined whether the amount of dirt is very small or large according to the output of the dirt detecting means at the time of the pre-washing step, and the detergent is put into the heating washing step without draining. Selective control is performed to enter or to perform drainage and water supply and perform the pre-washing process again. When oil ingredients such as animal ingredients are attached to the dishes, the water temperature during the pre-washing process is also considered, and the amount of dirt is determined according to the combination of the dirt detection means output and the water temperature detection means output, Selection control similar to the above is performed. In this way, by controlling the number of prewashes according to the amount of dirt, the effect of prewashing is maximized, the remaining dirt is avoided, and it is possible to save water (or hot water) and time. .

Second, according to the output of the dirt detecting means during the prewashing process, it is determined whether the dirt is a very small amount or a standard amount, and the detergent is put into the prewashing liquid without draining. Selective control is performed to enter into the heating and washing process, or to enter the heating and washing process by adding detergent after drainage and water supply. When oil ingredients such as animal ingredients are attached to the dishes, the water temperature during the pre-washing process is also considered, and the amount of dirt is determined according to the combination of the dirt detection means output and the water temperature detection means output, Selection control similar to the above is performed. In this way, by controlling whether or not to use the pre-washing liquid as it is during heat-washing according to the amount of dirt, the effect of pre-washing is maximized, the remaining dirt is avoided, and the water used (Or hot water) and time can be saved.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 are views showing a first embodiment of the present invention. FIG. 1 shows the configuration of the dishwasher, FIG. 2 shows a control flowchart, and FIG. 3 shows changes in the output of the dirt detector (dirt detection means). In FIG. 1 and FIG. 4 showing a second embodiment to be described later, the same or equivalent members and devices as those in FIG. 9 are designated by the same reference numerals as those used above, and the duplicated description will be omitted. As shown in FIG. 1, in this embodiment,
A microcomputer 10 as a control means is provided, and among the light emitting element 8 and the light receiving element 9 constituting the dirt detecting means, the light emitting element 8 is connected to the microcomputer 10 via a light emitting element control circuit 11, and the light receiving element 9 receives light. It is connected to the microcomputer 10 through the element output processing circuit 12. A microcomputer 10 is connected to the pump 3 via a pump control circuit 13.
A microcomputer 10 is connected to the heater 14 provided at the bottom of the cleaning chamber 1 via a heater control circuit 15.

Next, a control method by the microcomputer 10 of the dishwasher configured as described above will be described with reference to the flowchart of FIG. 2 and the change of the dirt detector output of FIG.
After water supply (step 21), the emission intensity of the light emitting element 8 of the dirt detector and the degree of amplification of the output of the light receiving element 9 are varied to initialize the dirt detector output to a preset value L ₀ ( Step 22). The pump 3 is rotated to start prewashing (step 23). After about 1 minute, the pump rotation was stopped (step 24), and after standing for 30 seconds to 1 minute, the dirt detector output L ₁ was measured, and the microcomputer 10 calculated L ₁ /
It is determined whether L ₀ is smaller than a predetermined value A (steps 25 and 26). If L ₁ / L ₀ is smaller than the predetermined value A, drain water (step 27), supply water (step 21), rotate the pump again for about 1 minute to perform prewashing (step 23), and stop the pump. And dirt detector output L
₂ is obtained (step 25). As a result of the judgment, L ₂ /
If L ₀ <A, drainage and water supply are performed again and prewashing is performed (steps 27, 21, 23). Repeating this, if L _n (n-th prewashing stain detector output) is L _n / L ₀ > A, drainage is not performed, heating is performed by the heater-on pump rotation (step 29) after detergent is added (step 28). Go into the wash.
The heating and washing and the subsequent steps are almost the same as in the case of FIG.

A second embodiment of the present invention is shown in FIGS. This embodiment is basically the same as the first embodiment, but the thermistor 16 as the water temperature detecting means for detecting the water temperature in the cleaning chamber 1 is attached to the cleaning chamber 1, and the temperature detecting circuit 1
It is connected to the microcomputer 10 via 7. This is different from the first embodiment in that the water temperature during prewashing is taken into consideration. This embodiment is effective when a constant water temperature cannot always be obtained by washing with hot water supply.

Next, a control method by the microcomputer 10 of the above dishwasher will be described with reference to the flowchart of FIG. 5 and the change of the dirt detector output of FIG. After water supply (hot water),
The emission intensity of the light emitting element 8 of the dirt detector and the degree of amplification of the output of the light receiving element 9 are varied to initialize the dirt detector output to a preset value L ₀ (step 31,
32). The pump 3 is rotated to start prewashing and the water temperature is detected by the thermistor 16 (steps 33 and 34). After about 1 minute, the pump rotation is stopped (step 35), and after leaving for 30 seconds to 1 minute, the dirt detector output L ₁ is measured (step 36). At this time, when the previous water temperature is 50 ° C. or higher, if L ₁ / L ₀ is smaller than the predetermined value B (steps 37 and 38), drainage (step 39), after performing water supply, again for about 1 minute. After the rotation of the pump, the pump is stopped and the dirt output L ₂ is obtained (steps 31 to 36). Similarly, when the water temperature is 50 ° C. or lower, if L ₁ / L ₀ is smaller than another predetermined value C (steps 37 and 41), drainage (step 4)
2) Water supply, prewashing again, and dirt detector output L ₂ are obtained (steps 31 to 36). Here, the water temperature of 50 ° C. is the temperature at which the animal oil component melts, and this is taken into consideration here. Depending on the case, a case such as a temperature at which the vegetable oil is dissolved may be added. By repeating the above control, L _n (detector output of n-th prewashing) is L _n / L ₀
> B (50 ° C. or higher) or L _n / L ₀ > C (50 ° C. or lower), drainage is not performed, and after detergent is added (step 42),
The heating and washing is started by rotating the heater on pump (step 43).

7 and 8 show a third embodiment of the present invention. The present example is a case of washing by hot water supply at 50 ° C. or higher, and the same dishwasher as that shown in FIG. 4 is used. A control method by the microcomputer of this embodiment will be described with reference to the flowchart of FIG. 7 and the change of the dirt detector output in FIG. After hot water supply, the light emission intensity of the light emitting element 8 of the dirt detector and the degree of amplification of the output of the light receiving element 9 are varied to initialize the dirt detector output to a preset value L ₀ (steps 51 and 52). . The pump 3 is rotated to start prewashing (step 53). After about 1 minute, the pump rotation is stopped and left for 30 seconds to 1 minute, and the dirt detector output L ₁ is measured (steps 54 and 55). If this L ₁ / L ₀ is larger than a predetermined value D (step 54). 56), since it can be judged that the pre-washing liquid is clean and the amount of dirt adhering to the dishes is very small, the detergent-addition heating washing step is performed (steps 60, 6).
1). If D> L ₁ / L ₀ > E (step 56,
57), it is determined that the stain is standard, and after the drainage and the water supply, the detergent charging and heating washing are started (steps 59 to 61). L ₁ / L
_{If 0} <E (step 57), it is determined that the amount of dirt is large, drainage (step 58), and pre-washing after hot water supply are repeated (steps 51 and 53).

With the above-described embodiments, it is possible to perform control according to each stain.

[0015]

As described above, according to the present invention,
First, whether to transfer the detergent to the heating washing process after the pre-washing process according to either the output of the dirt detecting unit and the water temperature detecting unit during the pre-washing process or the output of the dirt detecting unit. Alternatively, if the prewash process is selected again after draining and supplying water, the number of prewash cycles can be controlled according to the amount of dirt even when the dirt contains oil components such as animal ingredients. As a result, the effect of pre-washing is maximized, the remaining dirt is avoided, and the amount of water used (or hot water) and time can be saved.

Secondly, a detergent is added to the pre-washing solution after the pre-washing step in accordance with either the output of the dirt detecting means and the water temperature detecting means during the pre-washing step or the output of the dirt detecting means. Since it is selected whether to move to the heating washing process by heating or to drain and supply water and then add detergent to move to the heating washing process, when dirt contains an oil component such as animal. Also, depending on the amount of dirt, whether to use the pre-washing liquid as it is during heating and washing is selected to maximize the effect of pre-washing, avoiding residual dirt and using water (or hot water). You can save time.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a first embodiment of a dishwasher according to the present invention.

FIG. 2 is a flowchart showing a control method of the first embodiment.

FIG. 3 is a diagram showing a change in a dirt detector output in the first embodiment.

FIG. 4 is a configuration diagram of a second embodiment of the present invention.

FIG. 5 is a flowchart showing a control method of the second embodiment.

FIG. 6 is a diagram showing changes in the output of a stain detector in the second embodiment.

FIG. 7 is a flowchart showing a control method of a third embodiment of the present invention.

FIG. 8 is a diagram showing a change in detector output in the third embodiment.

FIG. 9 is a block diagram of a conventional dishwasher.

FIG. 10 is a flowchart showing a control method of the conventional example.

FIG. 11 is a diagram showing a change in an output of a dirt detector in the conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Washing room 8 Light emitting element 9 Light receiving element which constitutes dirt detection means together with light emitting element 10 Microcomputer (control means) 16 Thermistor (water temperature detection means)

Claims (2)

[Claims] 1. A dishwasher having a dirt detecting means for detecting the degree of dirt of the cleaning liquid and a water temperature detecting means for detecting the temperature of the cleaning liquid, wherein both the dirt detecting means and the water temperature detecting means during a pre-washing process. Depending on either the output or the output of the dirt detection means, after the pre-washing step, a detergent is added to shift to the heating-washing step, or the pre-washing step is performed again after draining and supplying water. A dishwasher comprising control means for making a selection. 2. A dishwasher having a dirt detecting means for detecting the degree of dirt of the cleaning liquid and a water temperature detecting means for detecting the temperature of the cleaning liquid, wherein both the dirt detecting means and the water temperature detecting means in a pre-washing process. Depending on the output or the output of the dirt detection means, after the pre-washing step, the detergent is added to the pre-washing liquid to shift to the heating washing step, or the detergent is added after draining and supplying water. And a control means for selecting whether to proceed to the heating and washing step.