KR101741258B1 - A control method of a dishwasher - Google Patents

Abstract

The present invention relates to a method of controlling a dishwasher.
A control method of a dishwasher according to an embodiment of the present invention includes a washing tank for storing dishes, a sump for storing washing water sprayed by the washing tub, and a washing motor provided for the sump and providing a driving force for circulating washing water Wherein the water is supplied to the sump; The cleaning motor is initially driven at a first rotation speed for a first set time; The cleaning motor being driven at a second rotation speed higher than the first rotation speed; Measuring a voltage Duty or a current value applied to the cleaning motor; And determining whether the cleaning motor is driven at a target rotation speed, based on the measured voltage Duty or current value.

Description

[0001] The present invention relates to a control method of a dishwasher,

An embodiment of the present invention relates to a control method of a dishwasher, and more particularly, to a control method of a dishwasher for controlling the driving of a washing pump to reduce noise.

Generally, a dishwasher is a device that cleans dishes by spraying washing water on dishwashes containing food or dirt.

In detail, after the dishwasher supplies clean water to the sump provided at one side of the washing tub, the washing water injection mechanism injects washing water into the dishes in the washing tub to wash the dishes. The washing water used for washing dishes is returned to the sump, and then supplied to the washing water injector through the filter device in the sump.

When the dishes are washed through the above-described process, the washing water existing in the washing tub and the sump is drained to the outside. At this time, the foreign matters filtered by the filter device may be discharged to the outside of the dishwasher together with the washing water.

The dishwasher may be provided with a washing pump for flowing the supplied washing water into the washing tank. The cleaning pump is provided in the sump.

After the water supply is completed, the washing pump pumps the washing water to the washing tub. At this time, the target frequency can be set in advance in the cleaning motor provided in the cleaning pump.

On the other hand, the sump may not be hermetically sealed to the outside of the dishwasher. In this case, the sump may be connected to the outside air.

During the initial operation of the washing pump, a predetermined amount of air can be introduced together with the washing water. Since the air is lighter than the washing water and has a larger volume, it can act as a load less than washing water for the motor of the washing pump.

In a state where a load smaller than the expected load is applied, excessive noise may be generated in the cleaning pump when the cleaning pump is initially driven to the target frequency.

In Fig. 9, the change in voltage Duty of the cleaning motor over time is shown.

When the driving of the cleaning pump is stabilized according to a predetermined target frequency, that is, when air is not introduced into the cleaning pump, the voltage Duty (on / off ratio of the voltage applied to the motor) w2).

Such a waveform is measurable in a state where a predetermined time has elapsed since the cleaning pump is driven, and can be understood as a range of a normal level.

On the other hand, when the cleaning pump is initially driven to the target frequency, that is, when the air is introduced into the cleaning pump together with the cleaning water, the voltage Duty over time is represented by a waveform w1 having an amplitude B.

Here, the amplitude B is formed to have a larger value than the amplitude A.

In this way, according to the conventional dishwasher, when the washing pump is initially driven at the target frequency, a voltage duty value exceeding a normal level range appears, and thus excessive noise is generated in the washing pump.

Meanwhile, although FIG. 9 shows a change in the value of the voltage Duty with respect to time, this phenomenon can be confirmed even when the current value applied to the cleaning motor is measured.

That is, when the cleaning motor is initially driven with the target frequency of the cleaning motor, a current value exceeding the normal level range can be measured. As a result, excessive current is applied to the load applied to the cleaning pump, which results in excessive noise.

It is an object of the present invention to provide a control method of a dishwasher which can reduce the generation of noise during the initial operation of the cleaning pump.

A control method of a dishwasher according to an embodiment of the present invention includes a washing tank for storing dishes, a sump for storing washing water sprayed by the washing tub, and a washing motor provided for the sump and providing a driving force for circulating washing water Wherein the water is supplied to the sump; The cleaning motor is initially driven at a first rotation speed for a first set time; The cleaning motor being driven at a second rotation speed higher than the first rotation speed; Measuring a voltage Duty or a current value applied to the cleaning motor; And determining whether the cleaning motor is driven at a target rotation speed, based on the measured voltage Duty or current value.

According to another aspect of the present invention, there is provided a method of controlling a dishwasher including a washing tank for storing dishes, a sump for storing washing water sprayed by the washing tub, and a washing motor provided for the sump, Wherein the sump is watered; The cleaning motor is initially driven at a first rotation speed lower than a preset target rotation speed; The cleaning motor being driven at a second rotation speed higher than the first rotation speed; Recognizing that the discharge of the air present in the sump is completed; And a step in which the cleaning motor is driven at a rotational speed higher than the second rotational speed.

According to the control method of the dishwasher according to the embodiment of the present invention, when the washing pump is operated at a frequency lower than the target frequency at the time of initial driving, noise caused by inflow of air into the washing pump can be reduced .

Further, since the frequency of the cleaning motor is controlled according to whether or not a normal voltage duty value or current value is measured after the initial driving of the cleaning pump, there is an effect that low noise can be maintained even after the cleaning motor is adjusted to the target frequency.

In addition, since an appropriate level of frequency (low frequency) is applied according to the load during the initial driving of the cleaning pump, the cleaning motor is not overloaded, and the life of the cleaning motor can be extended.

Further, when the cleaning pump is initially driven, an excessive current is not applied to the cleaning motor, so that power consumption can be reduced.

1 is a sectional view of a dishwasher according to an embodiment of the present invention.
2 is a bottom view of a sump according to an embodiment of the present invention.
3 is a cross-sectional view taken along line I-I 'of FIG.
4 is a cross-sectional view taken along line II-II 'of FIG.
5 is a cross-sectional view illustrating a structure of a filter unit according to an embodiment of the present invention.
6 is a block diagram showing the configuration of a dishwasher according to an embodiment of the present invention.
7 is a flow chart showing a method of controlling a dishwasher according to an embodiment of the present invention.
8 is a graph showing a change in frequency of the cleaning motor according to the embodiment of the present invention.
9 is a graph showing a change in voltage duty of the cleaning motor according to the prior art.

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings. It should be understood, however, that there is no intention to limit the spirit of the invention to the embodiments shown, and that other embodiments falling within the spirit of the invention or other inventions contemplated by way of addition, alteration, .

1 is a sectional view of a dishwasher according to an embodiment of the present invention

1, a dishwasher 1 according to an embodiment of the present invention includes a case 10 forming an outer appearance, a tub 11 accommodated in the case 10 to form a washing tub, A door 12 provided on the front surface of the tub 11 to open and close the washing tub 11 and a sump 20 provided below the tub 11 for storing wash water.

Inside the tub 11, an upper rack 13 and a lower rack 14, in which dishes are stored, are provided. The upper rack 13 is spaced a predetermined distance above the lower rack 14. The upper rack 13 and the lower rack 14 are guided by guide rails (not shown) provided on the inner surface of the tub 11 and can be drawn out to the front of the tub 11.

A top nozzle 15, an upper nozzle 16 and a lower nozzle 17 for spraying wash water supplied from the sump 20 into the washing tank are provided on the upper side of the sump 20. [

In detail, the lower nozzle 17 is coupled to an upper surface of the sump 20 to spray wash water to the lower portion of the wash tank, and the sprayed wash water is directed to a tableware installed in the lower rack 14. The sump 20 is provided with a lower nozzle coupling portion 62 coupled to the lower nozzle 17.

The upper nozzle 16 is positioned at a central portion of the washing tub and injects washing water toward the upper rack 13. The top nozzle 15 is disposed at a ceiling portion of the tub 11 to inject washing water downward, do.

On the upper side of the sump 20, a wash water guide 40 is provided for moving the wash water supplied from the wash pump. The washing water moved through the washing water guide 40 may be sprayed toward the upper rack 13 through the top nozzle 15 or the upper nozzle 16. [ The sump 20 is provided with a guide connection portion 64 to be coupled to the washing water guide 40.

FIG. 2 is a bottom view of a sump according to an embodiment of the present invention, FIG. 3 is a sectional view taken along line I-I 'of FIG. 2, FIG. 4 is a sectional view taken along line II- 5 is a cross-sectional view illustrating a structure of a filter unit according to an embodiment of the present invention.

2 to 5, the sump 20 according to the embodiment of the present invention is provided with a filter unit 50 for allowing washing water, which has been washed in the tub 11, A washing pump 70 for pumping the washing water filtered through the filter unit 50 and a washing pump 70 for washing water flowing through the washing pump 70 to flow into the lower nozzle 17 or the washing water guide 40. [ And an oil shut-off unit 80 for switching or opening and closing.

In detail, the filter unit 50 includes a first filter 52 having a plurality of holes of a first size, forming a part of the lower end of the washing space of the tub 11, A second filter 53 having a plurality of holes larger than the first size and a third filter 54 provided inside the sump 20 and having a plurality of holes smaller than the first size. Here, the first filter 52 is provided on a part of the upper surface of the sump 20.

The filter unit 50 includes a filter housing 51 for receiving the second filter 53 and the third filter 54.

A filter inlet 51a is formed in the upper portion of the filter housing 51 to allow the washing water to flow into the filter unit 50. The washing water flows into the filter housing 51 through the filter inlet 51a and the foreign matter is filtered through the second and third filters 52 and 53 and the third filter 54.

At a lower side of the filter housing 51, there is provided a pump inlet 58 for allowing the filtered wash water to flow into the wash pump 70. The washing water stored in the sump 20 can be flowed toward the pump inlet portion 58 through the filter portion 50 by the suction force of the washing pump 70.

The cleaning pump 70 includes a cleaning motor 71 that provides a driving force and an impeller 72 that is rotatably provided by the driving force of the cleaning motor 71. The impeller portion 72 may be disposed below the cleaning motor 71.

A pump discharge portion 78 is provided at one side of the Süperk pump 70 to discharge wash water from the wash pump 70.

The washing water flows into the impeller portion 72 through the pump inlet portion 58 and is discharged through the pump discharge portion 78 through the impeller portion 72.

A heater 68 is provided at one side of the cleaning pump 70 to heat the cleaning water while the wash water is flowing. The washing water can be cleaned in a state where the washing water is heated by the heater 68 at a high temperature, so that the washing efficiency is improved.

The heater (68) may be disposed below the impeller (72).

The flow path opening and closing part 80 is connected to the pump discharge part 78. The flow path opening and closing part 80 includes an opening and closing valve 82 for adjusting the flow path of the washing water and an opening and closing driving part 81 for driving the opening and closing valve 82.

The washing water flowing into the flow path opening and closing part 80 may flow into the lower nozzle coupling part 62 or the guide connecting part 64 while passing through the opening and closing valve 82.

That is, when the washing water should flow to the lower nozzle 17, the washing water is moved to the lower nozzle coupling part 62 by the operation of the opening / closing valve 82. On the other hand, when it is necessary to flow into the upper nozzle 16 or the top nozzle 15, the washing water can be moved to the guide connecting portion 64.

The wash water guide 40 may include a separate flow path, for example, a top nozzle flow path (not shown) and an upper nozzle flow path (not shown) communicating with the top nozzle 15 or the top nozzle 16, respectively And the washing water can be transferred to the top nozzle flow path or the upper nozzle flow path under the control of the opening / closing valve 82.

The top nozzle 15, the top nozzle 16 and the bottom nozzle 17 are selectively opened so that the washing water may be injected only through some of the nozzles 15, 16 and 17, 16, 17) are all open so that wash water may be injected through all of the nozzles 15, 16, 17.

One side of the filter unit 50 is provided with a drain pump 90 for providing a suction force for draining the wash water and a drain pump 90 provided between the filter unit 50 and the drain pump 90 for draining wash water and foreign matter. (59).

A drain hole 59a is formed in the lower portion of the filter housing 51 to drain the washing water.

When the drain pump (90) is driven, the washing water stored in the sump (20) is discharged through the drain hole (59a) together with foreign matter remaining in the filter (50).

The washing water passing through the drain hole 59a may be discharged to the outside of the dishwasher through the drain portion 59 and the drain pump 90. [

The flow path opening and closing part 80 includes a case 83 in which the washing water introduced through the washing pump 70 is stored. The case 83 defines a wash water storage portion 84 for storing wash water.

The operation of the dishwasher according to the above configuration will be briefly described.

The dishwasher 1 can be driven by a stroke such as preliminary washing, main washing, rinsing, heating rinsing and drying.

The preliminary washing is a step of removing dirt from the center of the protein before the main washing. The main washing is a process of performing main washing using heated washing water and detergent. The rinsing and heating rinsing are performed by using a foreign substance or detergent It can be understood as a washing administration.

Between the preliminary washing and main washing, between the main washing and the rinsing, between the rinsing and the heating rinsing, the washing water can be drained and supplied.

Wash water is supplied from the outside and stored in the sump 20. When the washing pump 70 is driven, the washing water is supplied to the top nozzle 15, the top nozzle 16 and the bottom nozzle 17 simultaneously or selectively through the washing pump 70 and the flow path opening / / RTI >

The sprayed washing water is stored in the sump 20 after washing dishes stored in the racks 13 and 14. The foreign substances are filtered through the filter unit 50 by the suction force of the washing pump 70, .

Thereafter, the cleaned wash water may be injected again into the washing tub of the tub 11 through the washing pump 70 and the flow path opening / closing part 80. This cleaning procedure can be repeated many times.

6 is a block diagram showing the configuration of a dishwasher according to an embodiment of the present invention.

6, the dishwasher 1 according to the embodiment of the present invention includes a washing pump 70 including the washing motor 71 and the impeller portion 72, And a control unit 100 for controlling the driving of the cleaning pump 70 in accordance with the detection result of the detection unit 150. [

The detection unit 150 includes a voltage detection unit 151 for measuring a change in duty (voltage on / off ratio) of a voltage applied to the cleaning motor 71 and a voltage detection unit 151 for measuring a current applied to the cleaning motor 71 Current detection unit 152 is included.

The duty value of the voltage is a controllable value for controlling the frequency of the cleaning motor 71. [

The target frequency (or the target rotational speed) for generating a predetermined driving force may be preset in the cleaning motor 71. [

The cleaning motor 71 is driven at an initial frequency (rotation number) lower than the target frequency at the time of initial driving and may be driven for a certain time at a frequency (rotation number) higher than the initial frequency before being raised to the target frequency .

The duty value or the current value of the voltage applied to the cleaning motor 71 may be detected through the voltage detection unit 151 or the current detection unit 152 in the process of driving the cleaning motor 71 at a predetermined frequency have.

The control unit 100 may control a frequency applied to the cleaning motor 71 based on a result detected by the voltage detection unit 151 or the current detection unit 152. The control unit 100 may control the cleaning motor 71 through the motor driving unit 110. [

FIG. 7 is a flow chart showing a control method of a dishwasher according to an embodiment of the present invention, and FIG. 8 is a graph showing a frequency change of a washing motor according to an embodiment of the present invention.

A control method of the dish washer according to the embodiment of the present invention will be described with reference to FIG.

First, washing water is supplied to the sump 20 of the dishwasher 1. The supply of the washing water may be performed before the pre-washing, before the main washing, before the rinsing and before the heating rinsing in the operation of the dishwasher (S11).

When the water supply to the sump 20 is completed, the cleaning motor 71 is turned on. The washing motor 71 is driven by a first rotational speed, and the first rotational speed may have a value lower than a preset target rotational speed. In one example, the first number of revolutions may be 800 RPM.

When the cleaning motor 71 is driven, the impeller 72 is rotated to generate a suction force. The washing water stored in the sump 20 can be supplied to the tub 11 by the suction force.

At this time, the air existing in the sump 20 flows into the washing pump 70 together with washing water, so that a low load may be applied to the washing motor 71.

However, since the first rotation speed has a value lower than the target rotation speed, noise that can be generated according to air inflow is smaller than when the cleaning motor 71 is driven at the target rotation speed (S12, S13).

It is determined whether or not the time when the cleaning motor 71 is driven by the first rotation speed has passed the first set time. For example, the first set time may be 20 seconds (S14).

When the first set time has elapsed, the washing motor 71 may be driven at the second rotational speed. The second rotation speed is greater than the first rotation speed, and may be 1000 RPM, for example.

However, the first set time has not elapsed, and the step S13 is continued (S15).

In the process of driving the cleaning motor 71 with the second rotation speed, the voltage Duty change or current value applied to the cleaning motor 71 is measured through the voltage detection unit 151 or the current detection unit 152 .

This control can be performed for a predetermined time (hereinafter referred to as a second set time). For example, the second set time may be about 10 seconds (S15, S16).

In step S17, it is determined whether the voltage Duty or the current value is within a predetermined range in the process of driving the cleaning motor 71 with the second rotation speed during the second set time period.

If it is determined that the voltage Duty or the current value is formed within the predetermined range during the second set time, the cleaning motor 71 may be driven at the third rotation speed. Here, the third rotation number forms a larger value than the second rotation number as the target rotation number.

When the voltage Duty or the current value is within the preset range, it can be recognized that the discharge of the air present in the sump 20 is completed. Thereafter, the cleaning motor 71 is driven stably .

However, if it is determined that the voltage Duty or the current value deviates from a preset range, step S13 and subsequent steps are performed again (S18).

In summary, the frequency of the cleaning motor 71 according to the present embodiment can be controlled to be stepped up as shown in Fig.

In detail, the cleaning motor 71 is driven at the number of revolutions of R1 during the initial driving of the cleaning motor 71 by applying power. The driving of the cleaning motor 71 may be performed for a predetermined time (ton to t1).

Then, when the predetermined time (ton to t1) elapses, the number of revolutions of the cleaning motor 71 becomes R2 higher than R1. The cleaning motor 71 is driven for a predetermined time (t1 to t2) by the rotation speed of R2, and the voltage Duty or the current value can be measured at this time.

If the voltage Duty or the current value is within the predetermined range, it can be understood that the cleaning motor 71 satisfies the condition to be stably driven. Therefore, the cleaning motor 71 can be driven at Rt (target rotation speed) higher than R2 from time t2 to toff when the cleaning motor 71 is turned off.

As described above, when the cleaning motor 71 is initially driven, it is driven at a rotational speed lower than the target rotational speed, so that noise generation due to air inflow can be reduced, and excessive current flow to the cleaning motor 71 can be prevented .

As a result, there is an effect that the power consumption due to the driving of the cleaning motor 71 can be reduced.

10: Case 20: Sump
50: filter unit 70: cleaning pump
71: Cleaning motor 90: Drain pump
100: control unit 110: motor driving unit
151: Voltage detector 152: Current detector

Claims (9)

1. A dishwasher provided with a washing tank for storing tableware, a sump for storing washing water sprayed by the washing tank, and a washing motor provided for the sump and providing a driving force for circulating washing water,
Supplying water to the sump;
The cleaning motor is initially driven at a first rotation speed lower than the target rotation speed for a first set time;
After the lapse of the first set time, the washing motor is driven at a second rotational speed higher than the first rotational speed and lower than the target rotational speed for a second set time period;
Measuring a change in a voltage Duty or a current value applied to the cleaning motor after the elapse of the second set time; And
Determining whether the cleaning motor is driven at the target number of revolutions based on the measured voltage Duty or current value,
Wherein when the measured voltage Duty or current value is within a predetermined range, the cleaning motor is adjusted to the target rotation speed. delete delete delete The method according to claim 1,
If the measured voltage Duty or current value is out of the preset range,
Wherein the rotation speed of the washing motor is controlled by the first rotation speed. delete delete The method according to claim 1,
The process of driving the washing motor at the target rotational speed includes:
Wherein the washing motor is maintained until a time when the washing motor is turned off. delete

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