JPH03215230A - Dish washer - Google Patents

Abstract

PURPOSE:To diminish noise and vibration caused by air sucked in the drain water during draining process and allow setting a required draining time period by a method wherein the draining performance of a drain pump is estimated depending on the water levels detected at two or more points, and the drain pump is controlled. CONSTITUTION:A water level detector 4 which detects the washing water levels at two or more points in a washing drum 2, a drain pump 11 which discharges washing water from the washing drum 2 to the outside of a dish washer, and a controller 12 which controls the detection of signals from the water level detector 4 and the action of the drain pump 11 are provided. The water levels at two or more points in the washing drum 2 are detected by the water level detector 4 to estimate the performance of the drain pump 11 and control the drain pump 11. Therefore, the time at which washing water is drained completely is forecasted and the drain pump is stopped or the capacity of a motor is reduced. As a result, the noise and vibration caused by air sucked in drain water during draining process can be restrained, and the draining capacity can be accurately seized to set the draining time period and detect a failure in draining, resulting in stable operation of the dish washer with the performance maintained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a dishwasher for washing dishes.

BACKGROUND OF THE INVENTION Conventionally, this type of dishwasher has been constructed as shown in FIG.

That is, a cleaning tank 2 is provided inside the wooden body 1, and water or hot water is supplied into the cleaning tank 2 by a water supply valve 3. At this time, the amount of water supplied by the water level detection device 4 is adjusted to be suitable for cleaning. During operation of the device, cleaning water is supplied to the inside of the cleaning tank 2 by a cleaning pump 6 installed in a pump chamber connected to the other side of the drainage hole arranged at the bottom of the cleaning tank 2 and driven by a motor 6. circulate. That is, in this circulation, the cleaning water flows from the drainage hole to the cleaning pump;
6, the washing pump 6 supplies the water to the washing nozzle 7 at the inner bottom of the washing tank 2, where it is sprayed, and after washing the dishes, it returns to the drain hole again. A heater 8 for heating the cleaning water is installed between the cleaning nozzle end and the bottom of the cleaning tank 2. In addition, above the washing nozzle V 7, there is a tableware nozzle V 7 designed to allow dishes to be placed in an orderly manner and to effectively spray washing water onto the dishes.
is installed. The tableware cup 9 is provided with a plurality of moving rollers and can be pulled out to the outside of the front surface of the wooden body 1. A door 10 that can be opened and closed is attached to the folded front part of the cleaning tank 2.

Further, a drainage pump 11 is also provided to discharge the washing water to the outside of the machine. The control device 12 controls these parts and operates the dishwasher.

If we look at the conventional control of the operation of the drainage pump 11, in most cases the control is controlled by the control device 12 based on time.

That is, they are operated only according to a predetermined sequence.

Problems to be Solved by the Invention However, when looking at dishwashers with such a configuration, noise and vibration become a problem during the draining process. The drain pump 11 discharges the wash water outside the machine, so if there is wash water, the drain pump 11 does its job, so noise and vibrations are not much of a problem. If the water runs out,
Drain pump 1 when air is mixed in the cleaning water.
1 is rotating, the noise caused by its rotation is much greater than when there is washing water. Also, the drainage pump 11
The pump does too much work and is too powerful, so that energy is used as its own vibration, resulting in extremely large vibrations. Particularly recently, as dishwashers are used at night, there is a strong need to reduce noise and vibration, so the noise and vibration of the drain pump 11 is a big problem.

Furthermore, in conventional dishwashers, it has not been possible to accurately grasp the drainage capacity of the drainage pump 11, which varies depending on the condition of the drainage hose and the like. Therefore, it was not possible to understand the amount of water remaining in the drainage process or problems related to drainage, such as incorrect drainage. In the draining process that takes a certain period of time, if the draining capacity decreases, there will be a lot of residual water, making it impossible to ensure sufficient rinsing performance, and the dishwasher will not be able to provide sufficient performance. In addition, drainage defects are detected by resetting the water level detection device after the draining process is completed.Water level detection devices that use micro-sinches, which have a very quick switch reset point, detect drainage defects. difficult to discover accurately. This is because during cleaning, the cleaning water adheres to various parts or evaporates, and the water level drops at the end of cleaning.

SUMMARY OF THE INVENTION An object of the present invention is to suppress the noise and vibration of the drain pump during the draining process, to make the operation of the dishwasher quieter, and to ensure its operation to ensure performance.

Means for Solving the Problems In order to achieve the above object, the present invention provides a cleaning tank, a water level detection device that detects the water level of a plurality of cleaning waters inside the cleaning tank, and a water level detection device that detects the water level of a plurality of cleaning waters inside the cleaning tank, and a The drain pump is equipped with a drain pump that discharges wash water, and a control device that detects signals from the water level detection device and controls the operation of the drain pump, and controls the drain pump based on the plurality of wash water level detection signals. It is something.

action The effect of this technical means is as follows.

That is, the capacity of the drainage pump is estimated by measuring the water levels at two or more points using a water level detection device that detects the water levels of a plurality of cleaning waters inside the cleaning tank, and the operation of the drainage pump is controlled accordingly. Therefore, by predicting the point in time when the cleaning water will run out and stopping the operation of the drainage pump or reducing the capacity of the motor, noise and vibrations caused by air being trapped during the drainage process can be suppressed. In addition, by accurately understanding the drainage capacity, the drainage time can be set and drainage failure can be detected.

Let me say a little more about water level prediction.

It is very difficult to measure at one point when the washing water runs out using a water level detection device. This is because the water level detection device uses the amount and pressure of washing water, so it is difficult to detect when there is no washing water. Therefore, by estimating the drainage capacity by measuring the water level at two or more points and setting a time limit necessary for discharging the remaining amount of water, it is possible to estimate when the washing water will run out.

Embodiment Hereinafter, one embodiment of the present invention will be described based on the accompanying drawings. The basic configuration of the dishwasher of the present invention is the same as that shown in FIG. 3, and the same parts are used. Identical parts are designated by the same reference numerals and description thereof will be omitted. In FIG. 1, the signal from the water level detector 4 is input to the control device multiple times during drainage, and the drainage capacity is determined based on the multiple signals from the water level detector 4 and the time between the two signals. .

FIG. 2 shows the relationship between the drainage time and the level of cleaning water in the cleaning tank 2. The horizontal axis shows the drainage time, and the vertical axis shows the washing water level, and ▲ and B are the detected water levels by the water level detection device 4. The water level of the washing water is set to the water level at which the drain pump 11 pumps air as the standard zero.

The water level detecting device 4 uses a pressure detecting element, has fixed characteristics with respect to the water level of the washing water, and can measure the necessary water level at any number of points. I wanted to do the above ▲. Point B can also be measured using this single water level detection device 4.

In addition, the capacity of the drain pump 11 is almost determined by the resistance of the drain hose, etc., so by measuring the time (Ta, Tb) at the detected water level (&, B), the cleaning time relative to that time and that water level can be determined. The current drainage capacity of the drainage pump 11 can be estimated from the relationship with the amount of water. therefore,
From the amount of the remaining wash water from Tb, it is possible to estimate the time at which the water level o (To) occurs, at which the air trapping state occurs.

By setting point A at approximately the washing water level and setting point B at the lowest reliable detection water level, the span between ▲ and B can be widened, and To can be estimated more accurately. . Then, when it becomes TO, the drainage pump 11
stop. Therefore, the subsequent drainage noise caused by the air intake of the drainage pump 11 is eliminated.

Furthermore, by estimating To, it is possible to set the drainage time only to the time that is truly necessary, so that reliable drainage can be achieved and a situation where there is a large amount of residual water can be avoided.

In addition, since you can set only the time that is really necessary, the drain pump 11 will be used to optimize the draining time, and you will not have to worry about the operating time of the dishwasher compared to conventional methods.
Operation time can be shortened.

Examples will be described using specific numerical values.

The relationship between the water level and water amount of the cleaning water based on the air intake standard is, for example, 30 to 2.6e at point A, 1QMM at point B, and o. Suppose it becomes s l. In the drainage process, if the time Tab from when the water level detection device 4 detects the water level at point ▲ to when it detects the water level at point B is 20 seconds, 2 liters of water is drained in 20 seconds, so there is no remaining water.
In order to drain 61, 5 seconds of draining is required. Therefore, the control device 12 stops the drain pump 11 five seconds after the water level detection device 4 detects the water level of the wash water at point B. Naturally, if the drainage capacity of the drainage pump 11 decreases and it takes a long time to go from point 5 to point B, the drainage pump 11 will be stopped after detecting the water level at point B depending on the proportion of the time. It will also take longer to do so.

Here, another embodiment will be described. Although the water level detection device 4 uses a pressure detection element in the embodiment, it may be any other device as long as it can detect a plurality of water levels. For example, one that uses ultrasonic waves, one that uses a frequency generated by a piezoelectric element, etc. can be considered.

In addition, there is no problem in measuring the water levels of a plurality of wash waters using a single water level detection device 12 or a plurality of devices.

1. Although the water level measurement points of the washing water are described as two measurement points, it is obvious that the accuracy can be further improved by taking more measurement points.

This is because the shape of the bottom of the cleaning tank 2 is rather complex, so the line showing the relationship between time and water level is not linear as shown in Figure 2, but has many points of inflection. This is why measuring points is effective.

Further, in the embodiment, the drainage pump 11 is immediately stopped at To, but the drainage noise can also be reduced by lowering the rotational speed of the drainage pump 110 from this point on to lower its capacity.

Furthermore, as mentioned above, although it is not possible to accurately measure the capacity of the drain pump 11 with conventional dishwashers,
In the present invention, the drainage capacity of the drainage pump 11 can be estimated by measuring the water levels of a plurality of wash waters, so the capacity can be accurately grasped, and when the drainage capacity has increased significantly, an abnormality is notified as a drainage failure. Anomaly notification can be performed by the stage 13, and a warning can be issued to the user. Therefore, the dishwasher can be operated reliably.

Effects of the Invention As described above, the present invention estimates the drainage capacity of the drainage pump by detecting a plurality of water levels and controls the drainage pump.
It is possible to suppress the noise and vibration caused by the air being sucked when the water is drained T, and it is possible to provide a dishwasher that operates quietly. In addition, since the really necessary drainage time can be set, reliable drainage can be expected, and the operation time can be shortened because the drainage process requires the minimum amount of time. Furthermore, by ensuring reliable drainage, rinsing performance and cleaning performance can be ensured. Furthermore, conditions such as drainage abnormalities can be accurately grasped, allowing for more accurate operation of the dishwasher.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a dishwasher showing an embodiment of the present invention, FIG. 2 is a diagram showing the relationship between washing water level and drain time, and FIG. 3 is a longitudinal sectional view of a conventional dishwasher. 2...Cleaning tank, 4...Water level detection device,
11... Drain pump, 12... Control device.

Claims (3)

[Claims] (1) A cleaning tank, a water level detection device that detects the water levels of a plurality of cleaning waters inside the cleaning tank, a drainage pump that discharges the cleaning water from the cleaning tank to the outside of the machine, and a signal from the water level detection device. A dishwasher comprising a control device that controls detection and operation of a drain pump, and controls the drain pump based on the plurality of wash water level detection signals. (2) The dishwasher according to claim 1, wherein the drain time is set based on the drain capacity of the drain pump determined by a plurality of wash water level detection signals. (3) The dishwasher according to claim 1, wherein the drainage abnormality notification is performed based on the drainage capacity of the drainage pump determined based on the detection signals of a plurality of wash water levels.