WO2019172532A1 - Refrigerator and controlling method thereof - Google Patents

Abstract

A control method of a refrigerator, according to an embodiment of the present invention, comprises the steps in which: a heating element of a sensor which is responsive to a change in the flow rate of air is turned off after being turned on for a predetermined time; a first sensing temperature (Ht1) of the heating element is sensed in a state in which the heating element is on, and a second sensing temperature (Ht2) of the heating element is sensed in a state in which the heating element is off; and the amount of frost on an evaporator is sensed on the basis of the temperature difference value between the first sensing temperature (Ht1) and the second sensing temperature (Ht2).

Description

Refrigerator and its control method

The present specification relates to a refrigerator and a control method thereof.

A refrigerator is a home appliance that can store an object such as food at a low temperature in a storage compartment provided in a cabinet. Since the storage compartment is surrounded by a heat insulating wall, the interior of the storage compartment may be maintained at a temperature lower than an external temperature.

The storage compartment may be divided into a refrigerating compartment or a freezing compartment according to the temperature band of the storage compartment.

The refrigerator may include an evaporator for supplying cold air to the storage compartment. The air in the storage compartment flows to the space where the evaporator is located and is cooled in the process of heat exchange with the evaporator, and the cooled air is supplied to the storage compartment again.

At this time, when the air heat-exchanged with the evaporator contains water, when the air is heat-exchanged with the evaporator, moisture condenses on the surface of the evaporator to form frost on the surface of the evaporator.

Since the frost acts as a flow resistance of the air, the greater the amount of frost that condenses on the surface of the evaporator, the greater the frost flow resistance, thereby lowering the heat exchange efficiency of the evaporator and increasing power consumption.

Thus, the refrigerator further includes defrosting means for defrosting the evaporator.

Prior art document Korean Laid-Open Patent Publication No. 2000-0004806 discloses a defrosting period variable method.

In the prior literature, the defrost cycle is adjusted using the cumulative operating time of the compressor and the outside air temperature.

However, when determining the defrosting cycle using only the cumulative operating time and the outside temperature of the compressor as in the prior art, there is a problem in that it does not reflect the amount of frost in the evaporator (hereinafter referred to as "deposition amount"), and thus actually defrosting. There is a disadvantage that it is difficult to accurately determine the time required.

That is, according to various environments, such as the user's refrigerator usage pattern, the degree of air holding moisture, the amount of implantation of the evaporator may be large or small. In the case of the prior literature, the disadvantage of determining the defrosting cycle is not reflected in the various environments. have.

Furthermore, in the case of the prior document, only the local amount of implantation of the evaporator is sensed, and the degree of implantation of the entire evaporator cannot be detected, which makes it difficult to know the exact time of defrosting.

Therefore, in spite of the large amount of implantation, the defrosting does not start and thus the cooling performance is reduced, or the defrosting is started even though the amount of implantation is small, resulting in an increase in power consumption due to unnecessary defrosting.

An object of the present invention is to provide a refrigerator capable of determining a defrosting operation time point using a parameter that depends on the amount of implantation of an evaporator and a control method thereof.

Another object of the present invention is to provide a refrigerator and a method of controlling the same, by which a defrosting necessary time according to the amount of implantation of the evaporator can be accurately determined using a sensor whose output value differs depending on the flow rate of air.

Another object of the present invention is to provide a refrigerator capable of accurately determining a defrosting point and a control method thereof even when the accuracy of the sensor used to determine the defrosting point is low.

Another object of the present invention is to provide a refrigerator and a method of controlling the same, in which a sensing logic for detecting an amount of implantation of an evaporator can be performed at an appropriate time.

In addition, an object of the present invention is to provide a refrigerator and a control method thereof that can improve reliability in consideration of external environmental changes in the process of sensing the amount of implantation of the evaporator.

One control method of the refrigerator for solving the above problems is a first sensing temperature (Ht1) of the heating element is detected when the heating element of the sensor reacts to the flow rate of the air is turned on, and the heating element is off On the basis of the temperature difference value of the second detection temperature (Ht2) of the heating element detected in the, characterized in that for detecting the amount of implantation of the evaporator.

For example, the first sensing temperature Ht1 is a temperature detected by the sensing element of the sensor immediately after the heating element is turned on, and the second sensing temperature Ht2 is a temperature of the sensor immediately after the heating element is turned off. It may be a temperature sensed by the sensing element.

As another example, the first sensing temperature Ht1 may be a minimum temperature value during the time that the heating element is turned on, and the second sensing temperature Ht2 may be a maximum temperature value after the heating element is turned off.

In addition, the heating element may be turned on while the storage compartment of the refrigerator is cooled. For example, the heating element may be turned on while the blower fan for cooling the storage compartment is driven.

The control method of the refrigerator of the present invention may include determining whether a temperature difference between the first sensing temperature Ht1 and the second sensing temperature Ht2 is less than a first reference difference and the first sensing temperature Ht1. If it is determined that the difference between the temperature and the second detection temperature (Ht2) is less than the first reference difference value, the method may further include performing a defrosting operation to remove frost generated on the surface of the evaporator.

The method may further include determining whether a temperature difference between the first sensing temperature Ht1 and the second sensing temperature Ht2 is less than a second reference difference value when the heating element is turned off after being turned on for a predetermined time. The heating element may be turned on, depending on whether a temperature difference between the first sensing temperature Ht1 and the second sensing temperature Ht2 is less than a second reference difference.

When the temperature difference between the first sensing temperature Ht1 and the second sensing temperature Ht2 is less than a second reference difference, the heating element may be turned on based on the accumulated cooling operation time of the storage compartment.

One control method of the refrigerator for solving the above problem is based on a temperature difference value between the lowest first sensing temperature Ht1 and the highest second sensing temperature Ht2 among the sensing temperatures of the heating element. , Detecting the amount of implantation of the evaporator.

In this case, the heating element may be turned on while the storage compartment of the refrigerator is cooled. For example, the heating element may be turned on while the blower fan for cooling the storage compartment is driven.

In addition, determining whether the temperature difference between the first sensing temperature (Ht1) and the second sensing temperature (Ht2) is less than the first reference difference value and the first sensing temperature (Ht1) and the second sensing temperature ( If it is determined that the temperature difference value of Ht2) is less than the first reference difference value, the method may further include performing a defrosting operation to remove frost generated on the surface of the evaporator.

The refrigerator for solving the above problems includes a heating element, a sensor including a sensing element sensing a temperature of the heating element, and a first sensing temperature Ht1 of the heating element detected when the heating element is turned on. The controller may include a controller configured to detect an amount of implantation of the evaporator based on a temperature difference value of the second sensing temperature Ht2 of the heating element detected when the heating element is turned off.

According to the proposed invention, since the defrosting necessary time is determined by using a sensor whose output value varies according to the amount of implantation of the evaporator in the bypass passage, there is an advantage in that the defrosting necessary time can be accurately determined.

In addition, even if the precision of the sensor used to determine the defrosting time is low, since the defrosting time can be accurately determined, there is an advantage that the unit cost of the sensor can be significantly reduced.

In addition, since the sensing logic for detecting the amount of implantation of the evaporator can be performed at an appropriate time, the power consumption is reduced and the convenience is improved.

In addition, since a change in the external environment (eg, a high internal load) is taken into consideration in the process of detecting the amount of implantation of the evaporator, there is an advantage that the product reliability is improved.

1 is a longitudinal sectional view schematically showing the configuration of a refrigerator according to one embodiment of the present invention;

Figure 2 is a perspective view of the cold air duct according to an embodiment of the present invention.

3 is an exploded perspective view showing a state in which a flow path cover and a sensor are separated from a cold air duct;

FIG. 4 is a diagram showing air flow in a heat exchange space and a bypass flow path before and after implantation of an evaporator; FIG.

5 is a view schematically showing a state where a sensor is disposed in a bypass flow path.

6 illustrates a sensor according to an embodiment of the present invention.

7 is a diagram showing thermal flow around a sensor according to the flow rate of air flowing through a bypass flow path.

8 is a control block diagram of a refrigerator according to one embodiment of the present invention.

9 is a flow chart showing a control method for detecting the amount of implantation of the evaporator according to an embodiment of the present invention.

10 is a flowchart illustrating a method of performing defrosting operation by determining a defrost need time of a refrigerator according to an embodiment of the present disclosure.

11 is a view showing a temperature change of the heating element according to the on / off of the heating element before and after the implantation of the evaporator according to an embodiment of the present invention.

12 is a flowchart illustrating a control method for determining an operation time of a heating element according to an embodiment of the present disclosure.

Hereinafter, some embodiments of the present invention will be described in detail with reference to the accompanying drawings. In adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are assigned to the same components as much as possible even though they are shown in different drawings. In addition, in describing the embodiments of the present invention, when it is determined that a detailed description of a related well-known configuration or function interferes with the understanding of the embodiments of the present invention, the detailed description thereof will be omitted.

In addition, in describing the components of the embodiment of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are only for distinguishing the components from other components, and the nature, order or order of the components are not limited by the terms. If a component is described as being "connected", "coupled" or "connected" to another component, that component may be directly connected or connected to that other component, but between components It will be understood that may be "connected", "coupled" or "connected".

1 is a vertical cross-sectional view schematically showing the configuration of a refrigerator according to an embodiment of the present invention, Figure 2 is a perspective view of a cold air duct according to an embodiment of the present invention, Figure 3 is a flow path cover and sensor in the cold air duct An exploded perspective view showing the separated state.

1 to 3, the refrigerator 1 according to an embodiment of the present invention may include an inner case 12 forming a storage compartment 11.

The storage compartment 11 may include one or more of a refrigerating compartment and a refrigerating compartment.

A cold air duct 20 is formed in the rear space of the storage compartment 11 to form a flow path through which cold air supplied to the storage compartment 11 flows. In addition, an evaporator 30 is disposed between the cold air duct 20 and the rear wall 13 of the inner case 12. That is, a heat exchange space 222 in which the evaporator 30 is disposed is defined between the cold air duct 20 and the rear wall 13.

Accordingly, the air in the storage compartment 11 flows into the heat exchange space 222 between the cold air duct 20 and the rear wall 13 of the inner case 12 to exchange heat with the evaporator 30, and the cold air After flowing inside the duct 20, it is supplied to the storage chamber 11.

The cold air duct 20 may include, but is not limited to, a first duct 210 and a second duct 220 coupled to a rear surface of the first duct 210.

The front surface of the first duct 210 faces the storage chamber 11, and the rear surface of the first duct 220 faces the rear wall 13 of the inner case 12.

A cold air passage 212 may be formed between the first duct 210 and the second duct 220 in a state in which the first duct 210 and the second duct 220 are coupled to each other.

In addition, a cold air inlet hole 221 may be formed in the second duct 220, and a cold air discharge hole 211 may be formed in the first duct 210.

The cold air passage 212 may be provided with a blowing fan (not shown). Therefore, when the blowing fan is rotated, air passing through the evaporator 13 flows into the cold air flow path 212 through the cold air inlet hole 221, and the storage chamber 11 through the cold air discharge hole 211. To be discharged.

The evaporator 30 may be located between the cold air duct 20 and the rear wall 13, and the evaporator 30 may be located below the cold air inlet hole 221.

Therefore, the air of the storage chamber 11 is introduced into the cold air inlet hole 221 after the heat exchange with the evaporator 30 while rising.

According to this arrangement, if the amount of implantation of the evaporator 30 is increased, the amount of air passing through the evaporator 30 is reduced, thereby reducing the heat exchange efficiency.

In the present embodiment, the defrosting necessary time of the evaporator 30 may be determined by using a parameter that changes according to the amount of implantation of the evaporator 30.

For example, in the cold air duct 20, at least a part of the air for flowing through the heat exchange space 222 is bypassed, and an implantation sensing device for determining a defrost need time using a sensor whose output is different according to the flow rate of the air. It may further include.

The implantation detecting apparatus may include a bypass passage 230 for bypassing at least a portion of the heat exchange space 222 and a sensor 270 positioned on the bypass passage 230. .

Although not limited, the bypass flow path 230 may be formed to be recessed in the first duct 210. Alternatively, the bypass flow path 230 may be provided in the second duct 220.

The bypass flow path 230 may be formed as a portion of the first duct 210 or the second duct 220 is recessed in a direction away from the evaporator 30.

The bypass flow path 230 may extend in the vertical direction from the cold air duct 20.

The bypass flow path 230 may face the evaporator 30 within a left and right width range of the evaporator 30 so that the air in the heat exchange space 222 may be bypassed to the bypass flow path 230. Can be arranged.

The implantation detecting apparatus may further include a flow path cover 260 for allowing the bypass flow path 230 to be partitioned from the heat exchange space 222.

The flow path cover 260 may be coupled to the cold air duct 20 and may cover at least a portion of the bypass flow path 230 extending upward and downward.

The flow path cover 260 may include a cover plate 261, an upper extension part 262 extending from an upper side of the cover plate 261, and a barrier 263 provided below the cover plate 261. Can be.

FIG. 4 is a diagram showing air flow in a heat exchange space and a bypass flow path before and after implantation of an evaporator.

4 (a) shows the air flow before implantation, and FIG. 4 (b) shows the air flow after implantation. In this embodiment, for example, it is assumed that after the defrosting operation is completed, the state before the implantation.

First, referring to FIG. 4A, when no frost is present in the evaporator 30 or the amount of implantation is significantly small, most of the air passes through the evaporator 30 in the heat exchange space 222 (arrow). A). On the other hand, some of the air may flow through the bypass flow path 230 (see arrow B).

Referring to FIG. 4B, when the amount of implantation of the evaporator 30 is large (defrost is necessary), since the frost of the evaporator 30 acts as a flow path resistance, the heat exchange space 222 flows. The amount of air to be reduced is reduced (see arrow C), and the amount of air flowing through the bypass flow path 230 is increased (see arrow D).

As such, the flow rate (or flow rate) of air flowing through the bypass flow path 230 varies according to the amount of implantation of the evaporator 30.

In this embodiment, the sensor 270, the output value is changed according to the change in the flow rate of the air flowing through the bypass flow path 230, it can be determined whether or not defrosting based on the change in the output value.

Hereinafter, the structure and principle of the sensor 270 will be described.

5 is a view schematically showing a state in which a sensor is disposed in the bypass flow passage, FIG. 6 is a view showing a sensor according to an embodiment of the present invention, and FIG. 7 is a flow rate of air flowing through the bypass flow passage. Figure is a view showing the heat flow around the sensor according.

5 to 7, the sensor 270 may be disposed at a point in the bypass flow path 230. Accordingly, the sensor 270 may be in contact with air flowing along the bypass flow path 230, and the output value may be changed in response to a change in the flow rate of air.

The sensor 270 may be disposed at a position spaced apart from each of the inlet 231 and the outlet 232 of the bypass flow path 230. For example, the sensor 270 may be disposed at an intermediate point of the bypass flow path 230.

Since the sensor 270 is positioned on the bypass flow path 230, the sensor 270 may face the evaporator 30 within a left and right width range of the evaporator 30.

The sensor 270 may be, for example, a heating temperature sensor. In detail, the sensor 270 includes a sensor PC 271, a heating element 273 installed in the sensor PC 271, and a temperature of the heating element 273 provided in the sensor PC 271. It may include a sensing element 274 for sensing.

The heat generating element 273 may be a resistor that generates heat when a current is applied.

The sensing element 274 may sense the temperature of the heating element 273.

When the flow rate of the air flowing in the bypass flow path 230 is small, the amount of cooling of the heat generating element 273 by the air is small, the temperature detected by the sensing element 274 is high.

On the other hand, if the flow rate of air flowing in the bypass flow path 230 is large, the cooling amount of the heat generating element 273 is increased by the air flowing in the bypass flow path 230, the sensing element 274 The sensed temperature will be low.

The sensor PCB 271 may include a temperature detected by the sensing element 274 in the off state of the heating element 273, and a temperature detected by the sensing element 274 in the on state of the heating element 273. You can judge the difference.

The sensor PC 271 may determine whether a temperature difference value (for example, a maximum value) in the on / off state of the heating element 273 is less than or equal to the reference difference value.

For example, referring to FIG. 4 and FIG. 7, when the amount of implantation of the evaporator 30 is small, the flow rate of air flowing into the bypass flow path 230 is small. In this case, there is little heat flow of the heat generating element 273, and the amount cooled by air is small.

On the other hand, in the case where the amount of implantation of the evaporator 30 is large, the flow rate of air flowing into the bypass flow path 230 is large. Then, the heat of the heat generating element 273 is increased by the air flowing along the bypass flow path 230 and the amount of cooling is large.

Therefore, when the amount of implantation of the evaporator 30 is large, the temperature detected by the sensing element 274 is smaller than the temperature sensed by the sensing element 274 when the amount of implantation of the evaporator 30 is small.

Therefore, in the present exemplary embodiment, a difference between a temperature detected by the sensing element 274 while the heating element 273 is turned on and a temperature detected by the sensing element 274 when the heating element 273 is turned off If it is less than the reference temperature difference, it may be determined that defrost is necessary.

According to the present embodiment, the sensor 270 detects a change in the temperature of the heating element 273 that is varied by the air whose flow rate is variable according to the amount of implantation, and thus defrosting according to the amount of implantation of the evaporator 30. Accurately determine the time required.

The sensor 270 is a sensor housing 272 such that air flowing through the bypass flow path 230 is prevented from directly contacting the sensor PC 271, the heating element 273, and the temperature sensor 274. It may further include. The wire connected to the sensor PCB 271 may be drawn out of the sensor housing 272 in an open state of one side thereof, and the opened part may be covered by a cover part.

The sensor housing 271 may surround the sensor PCB 271, the heat generating element 273, and the temperature sensor 274.

8 is a control block diagram of a refrigerator according to one embodiment of the present invention.

Referring to FIG. 8, the refrigerator 1 according to an embodiment of the present invention compresses the sensor 270 described above, the defrosting device 50 operating for defrosting the evaporator 30, and a refrigerant. And a control unit 40 for controlling the compressor 60, a blower fan 70 for generating air flow, and the sensor 270, the defrosting device 50, the compressor 60, and the blower fan 70. It may include.

The defrosting device 50 may include a heater as an example. When the heater is turned on, heat generated by the heater is transferred to the evaporator 30 to melt frost generated on the surface of the evaporator 30. The heater may be connected to one side of the evaporator 30, or may be spaced apart from the position adjacent to the evaporator 30.

The compressor 60 is a device for compressing a low temperature low pressure refrigerant into a high temperature high pressure supersaturated gaseous refrigerant. Specifically, the high temperature and high pressure supersaturated gaseous refrigerant compressed by the compressor 60 flows into a condenser (not shown) to condense into a high temperature and high pressure saturated liquid refrigerant. Flows into the two-phase refrigerant at low temperature and low pressure.

The low-temperature, low-pressure two-phase refrigerant is evaporated into the low-temperature, low-pressure gas phase refrigerant while passing through the evaporator 30. In this process, the refrigerant flowing through the evaporator 30 exchanges heat with external air, that is, air flowing through the heat exchange space 222, thereby cooling the air.

The blowing fan 70 is provided in the cold air passage 212 to generate a flow of air. Specifically, when the blowing fan 70 is rotated, air passing through the evaporator 30 is introduced into the cold air flow path 212 through the cold air inlet hole 221, and through the cold air discharge hole 211. It is discharged to the storage chamber 11.

The controller 40 may control the heating element 273 of the sensor 270 to be turned on at a predetermined cycle.

In order to determine the need for defrosting, the heating element 273 may be in an on state for a predetermined time, and the sensing element 274 may sense a temperature of the heating element 273.

After the heating element 273 is turned on for a predetermined time, the heating element 274 may be turned off, and the sensing element 274 may sense the temperature of the turned off heating element 273. The sensor PC 263 may determine whether the maximum value of the temperature difference value of the on / off state of the heat generating element 273 is equal to or less than the reference difference value.

The defrosting device 50 may be turned on by the controller 40 when the maximum value of the temperature difference value of the on / off state of the heating element 273 is equal to or less than the reference difference value. have.

In the above description, the sensor PC 263 determines whether the temperature difference value of the on / off state of the heating element 273 is equal to or less than a reference difference value. However, the control unit 40 determines that the heating element ( It may be determined whether the temperature difference value in the on / off state of 273 is equal to or less than the reference difference value, and the defrosting device 50 may be controlled according to the determination result. That is, the sensor PC 263 and the controller 40 may be in an electrically connected state.

Hereinafter, a method of detecting the amount of implantation of the evaporator 30 using the heating element 273 will be described in detail with reference to the accompanying drawings.

9 is a flow chart showing a control method for detecting the amount of implantation of the evaporator according to an embodiment of the present invention. In this embodiment, a description will be given of a method of detecting the amount of implantation of the evaporator 30 in a state in which the storage compartment 11, for example, the freezer compartment is cooled and operated.

Referring to FIG. 9, in step S11, the heat generating element 27 is turned on.

Specifically, the heat generating element 27 may be turned on in the cooling operation of the storage compartment 11 (eg, the freezing compartment).

Here, the state in which the cooling operation of the freezer compartment is performed may mean a state in which the compressor 60 and the blower fan 70 are driven.

As described above, when the flow rate of the air increases as the amount of the evaporator 30 is increased or decreased, the detection accuracy of the sensor 260 may be improved. That is, if the flow rate of the air is large according to a large amount or a small amount of the amount of implantation of the evaporator 30, the amount of change in temperature sensed by the sensor 270 is increased, so that the determination of the defrosting necessary time may be accurate.

For this reason, the accuracy of the sensor can be increased only by detecting the idea of the evaporator 30 in a state where air flow is generated, that is, while the blower fan 70 is being driven.

Next, in step S13, the temperature of the heat generating element 273 is detected while the heat generating element 273 is turned on.

In detail, the heating element 273 may be turned on for a predetermined time, and at a certain point in time when the heating element 273 is turned on, the temperature of the heating element 273 by the sensing element 273 (Ht1). ) Is detected.

As the time for which the heat generating element 273 is turned on becomes longer, the temperature of the heat generating element 273 may increase gradually. In addition, the temperature of the heat generating element 273 may gradually increase and converge to the highest temperature point.

On the other hand, when the amount of frosting of the evaporator 30 is large, the flow rate of air flowing into the bypass flow path 230 increases, so that the heat generating element 273 is cooled by the air flowing through the bypass flow path 230. The amount is increased. Then, the highest temperature point of the heat generating element 273 may be set low by the air flowing through the bypass flow path 230.

On the other hand, when the amount of frosting of the evaporator 30 is small, since the flow rate of air flowing into the bypass flow path 230 decreases, the air flows through the bypass flow path 230. Cooling amount is reduced. Then, the highest temperature point of the heat generating element 273 may be set higher by the air flowing through the bypass flow path 230.

In the present embodiment, the temperature of the heating element 273 may be sensed when the heating element 273 is turned on. That is, in the present invention, it can be understood that the lowest temperature value of the heating element 273 is detected after the heating element 273 is turned on.

Next, in step S15, after a predetermined time has elapsed, the heat generating element 273 is turned off.

For example, the heating element 273 may be turned on for three minutes and then turned off.

When the heat generating element 273 is turned off, the temperature of the heat generating element 273 decreases rapidly due to air flowing in the bypass flow path 230.

As the time for which the heat generating element 273 is turned off increases, the temperature of the heat generating element 273 may decrease rapidly. The temperature of the heat generating element 273 decreases rapidly and then gradually decreases from a specific time point.

Next, in step S17, the temperature of the heat generating element 273 is detected while the heat generating element 273 is turned off.

Specifically, the temperature of the heat generating element 273 is sensed at some point when the heat generating element 273 is turned off.

In this embodiment, the temperature of the heat generating element 273 may be sensed when the heat generating element 273 is turned off. That is, in the present invention, it may be understood that the highest temperature value of the heating element 273 is sensed after the heating element 273 is turned off.

Next, in step S19, based on the temperature difference between the temperature detected when the heating element 273 is turned on and the temperature detected when the heating element 273 is turned off, the amount of implantation of the evaporator 30 is determined. To judge.

As described above, when the amount of frosting of the evaporator 30 is large, the flow rate of the air flowing into the bypass flow path 230 increases, and thus, the heat generating element may be formed by the air flowing through the bypass flow path 230. The cooling amount of 273) is increased. Then, the detected maximum temperature value of the heating element 273 becomes low, and as a result, the temperature difference between the lowest temperature value and the highest temperature value of the heating element 273 becomes large.

On the contrary, when the amount of frosting of the evaporator 30 is small, the flow rate of the air flowing in the bypass flow path 230 decreases, so that the heat generating element 273 is formed by the air flowing in the bypass flow path 230. Cooling amount is reduced. Then, the detected maximum temperature value of the heat generating element 273 becomes high, and as a result, the temperature difference between the lowest temperature value and the maximum temperature value of the heat generating element 273 becomes small.

As such, by sensing the lowest temperature value and the highest temperature value when the heating element 273 is turned on / off, the amount of cooling of the heating element 273 is precisely determined by the air flowing in the bypass flow path 230. You can judge.

In summary, when the temperature difference value between the lowest temperature value of the heat generating element 273 and the maximum temperature value is equal to or less than a reference value, it may be determined that the amount of implantation of the evaporator 30 is large. If it is determined that the amount of implantation of the evaporator 30 is large, defrosting operation may be performed.

Hereinafter, a detailed method of detecting the amount of implantation of the above-described evaporator 30 will be described in detail with reference to the accompanying drawings.

10 is a flowchart illustrating a method of performing defrosting operation by determining a defrost need time of a refrigerator according to an embodiment of the present invention, and FIG. 11 is a view illustrating a heating element before and after implantation of an evaporator according to an embodiment of the present invention. A diagram showing a temperature change of the heating element according to the on / off.

(A) of FIG. 11 shows the temperature change of the freezer compartment and the temperature change of the heating element before implantation of the evaporator 30, and FIG. 11 (b) shows the temperature change of the freezer compartment after implantation of the evaporator 30 and Show the change. In this embodiment, it is assumed that after the defrosting operation is completed, the state before the implantation.

10 and 11, in step S21, the heat generating element 27 is turned on.

Specifically, the heat generating element 273 may be turned on in a state in which a cooling operation of the storage compartment 11 (eg, a freezing compartment) is being performed.

For example, as shown in FIG. 11, the heat generating element 273 may be turned on at any point in time S1 during which the blowing fan 70 is being driven.

The blowing fan 70 may be driven for a predetermined time to cool the freezing compartment. At this time, the driving of the compressor 60 may be performed at the same time. Therefore, when the blowing fan 70 is driven, the temperature Ft of the freezing compartment is lowered.

On the other hand, when the heating element 273 is turned on, the temperature sensed by the sensing element 274, that is, the temperature Ht of the heating element 273 increases rapidly.

Next, in step S22, it is determined whether the blowing fan 70 is turned on.

As described above, the sensor 270 detects a change in temperature of the heating element 273 that is varied by air whose flow rate varies according to the amount of implantation of the evaporator 30. Therefore, if air flow does not occur, it becomes difficult for the sensor 270 to accurately detect the amount of implantation of the evaporator 30.

When the blowing fan 70 is being driven, in step S23, the temperature Ht1 of the heating element is detected.

In detail, the heating element 273 may be turned on for a predetermined time, and at some point in time when the heating element 273 is turned on, the temperature Ht1 of the heating element is detected by the sensing element 273. do.

In the present embodiment, the temperature Ht1 of the heat generating element 273 may be sensed when the heat generating element 273 is turned on. That is, the present invention senses the temperature immediately after the heating element 273 is turned on. Therefore, the sensing temperature Ht1 of the heating element may be defined as the lowest temperature when the heating element 273 is turned on.

Here, the first sensed temperature of the heat generating element 273 may be referred to as a "first sensing temperature Ht1."

Next, in step S24, it is determined whether the first reference time T1 has elapsed while the heat generating element 273 is turned on.

When the heating element 273 is kept in the on state, the temperature detected by the sensing element 274, that is, the temperature Ht1 of the heating element 273 may continue to increase. However, when the heating element 273 is kept on, the temperature of the heating element 273 may gradually increase and converge to the highest temperature point.

Here, the first reference time T1 during which the heat generating element 273 is kept in an on state may be three minutes, although not limited thereto.

When a predetermined time has elapsed while the heat generating element 273 is on, in step S25, the heat generating element 273 is turned off.

As illustrated in FIG. 11, the heat generating element 273 may be turned on for the first reference time T1 and then turned off. When the heat generating element 273 is turned off, the heat generating element 273 may be rapidly cooled by air flowing through the bypass flow path 230. Therefore, the temperature Ht of the heat generating element 273 drops rapidly.

However, when the off state of the heat generating element 273 is continuously maintained, the temperature Ht of the heat generating element gradually decreases, and the reduction width is significantly reduced.

Next, in step S26, the temperature Ht2 of the heating element is sensed.

That is, at a point in time S2 when the heat generating element 273 is turned off, the temperature Ht2 of the heat generating element is sensed by the sensing element 273.

In the present embodiment, the temperature Ht2 of the heat generating element can be detected when the heat generating element 273 is turned off. That is, the present invention senses the temperature immediately after the heat generating element 273 is turned off. Therefore, the sensing temperature Ht2 of the heating element may be defined as the maximum temperature in the state in which the heating element 273 is turned off.

Here, the second sensed temperature of the heat generating element 273 may be referred to as a “second sensing temperature Ht2”.

In summary, the temperature Ht of the heat generating element is first detected at the time S1 at which the heat generating element 273 is turned on, and then additionally detected at the time S2 at which the heat generating element 273 is turned off. . In this case, the first sensing temperature Ht1 detected for the first time becomes the lowest temperature when the heating element 273 is turned on, and the second sensing temperature Ht2 that is additionally sensed is determined by the heating element 273. It can be the highest temperature in the off state.

Next, in step S27, it is determined whether or not the temperature stabilization state is achieved.

Here, the temperature stabilized state may mean a state in which a high internal load is not generated, that is, a state in which the storage chamber is cooled normally. In other words, the temperature stabilization state may mean, for example, that the refrigerator door is not opened or closed, or a component (eg, a compressor, an evaporator, etc.) or a sensor 270 for cooling the storage compartment is not defective.

That is, by determining whether temperature stabilization is performed, the sensor 270 may accurately detect the amount of implantation of the evaporator 30.

In this embodiment, to determine the temperature stabilization state, it is possible to determine the amount of change in the freezer compartment temperature for a predetermined time. Or alternatively, in order to determine the temperature stabilization state, it is possible to determine the amount of change in the evaporator 30 temperature for a predetermined time.

For example, a state in which the amount of change in the freezer compartment temperature or the evaporator 30 temperature for a predetermined time does not exceed 1.5 degrees may be defined as a temperature stabilized state.

As described above, immediately after the heat generating element 273 is turned off, the temperature Ht of the heat generating element decreases sharply, and then the temperature Ht of the heat generating element may gradually decrease. Here, by determining whether the temperature (Ht) of the heat generating element decreases normally after a sudden drop, it may be determined whether temperature stabilization has been achieved.

When the temperature stabilization state is achieved, in step S28, the temperature difference between the temperature Ht1 detected when the heating element 273 is turned on and the temperature Ht2 detected when the heating element 273 is turned off Calculate the value ΔHt.

In step S29, it is determined whether the temperature difference value ΔHt is less than a first reference temperature value.

Specifically, when the amount of the frost of the evaporator 30 is large, the flow rate of the air flowing in the bypass flow path 230 increases, so that the heat generating element 273 is formed by the air flowing in the bypass flow path 230. The amount of cooling is increased. When the amount of cooling is increased, the temperature Ht2 of the heat generating element sensed immediately after the heat generating element 273 is turned off becomes relatively low as compared with the case where the amount of implantation of the evaporator 30 is small.

As a result, when the amount of implantation of the evaporator 30 is large, the temperature difference value DELTA Ht decreases. Accordingly, the degree of implantation of the evaporator 30 may be determined based on the temperature difference value ΔHt. Here, the first reference temperature value may be, for example, 32 degrees.

Next, when the temperature difference value ΔHt is less than the first reference temperature value, in step S30, the defrosting operation is performed.

When the defrosting operation is performed, the defrosting device 50 is driven and heat generated by the heater is transferred to the evaporator 30 to melt frost generated on the surface of the evaporator 30.

On the other hand, if the temperature stabilization state is not achieved in step S27 or if the temperature difference value DELTA Ht is equal to or greater than the first reference temperature value in step S29, the algorithm is terminated without performing defrosting operation.

In the present embodiment, the temperature difference value ΔHt may be defined as “logic temperature” for the detection of implantation. The logic temperature may be used as a temperature for determining the defrosting operation timing of the refrigerator and may be used as a temperature for determining the on timing of the heating element 273, which will be described later.

12 is a flowchart illustrating a control method for determining a driving time point of a heating element according to an exemplary embodiment. This embodiment can be understood as a control method for determining the timing (step S21) at which the heat generating element 373 is turned on in FIG.

11 and 12 together, in step S31, the heat generating element 27 is turned off. Here, step S31 may mean step S25 of FIG. 10 described above. That is, the present embodiment can be understood as a control method after step S25.

When the heat generating element 27 is turned off, it is determined in step S32 whether the logic temperature ΔHt is less than a second reference temperature value.

The reason for determining whether the logic temperature ΔHt is less than the second reference temperature value is to detect an amount of implantation of the evaporator 30.

For example, the second reference temperature value may be 35 degrees.

Specifically, in FIG. 10, the first reference temperature value for performing the defrosting operation is 32 degrees. In this case, the second reference temperature value may be set larger than the first reference temperature value. That is, even when the defrosting operation is completed, the amount of implantation of the evaporator 30 may be large, thereby detecting the amount of implantation of the evaporator 30 again.

When the logic temperature ΔHt is less than the second reference temperature value, in step S33, it is determined whether the operation time of the integrated freezer compartment reaches the second reference time. Here, the second reference time may be, for example, one hour.

Next, if the logic temperature ΔHt is less than the second reference temperature value, it is determined whether the blower fan 70 is driven in step S34.

When the blower fan 70 is driven, it is determined whether or not the temperature stabilization state is performed in step S35, and when the temperature stabilization state is achieved, the heating element 273 is turned on in step S36.

Here, the temperature stabilized state may mean a state in which no high load is generated or a state in which the storage chamber is cooled normally. In other words, the temperature stabilization state may mean, for example, that the refrigerator door is not opened or closed, or a component (eg, a compressor, an evaporator, etc.) or a sensor 270 for cooling the storage compartment is not defective.

In the present embodiment, in order to determine the temperature stabilization state, the heating element 273 may be turned on / off at a predetermined time interval. For example, in the process of determining the temperature stabilization state, the heating element 273 may be turned on / off at a predetermined time interval. In this case, the time point at which the heating element 273 is turned on / off to determine the temperature stabilization state may be a time point S0 at which the blowing fan 70 is turned on.

That is, immediately after the blower fan 70 is turned on, the heating element 273 may be turned on / off at a predetermined time interval. For example, when the blower fan 70 is driven, the heating element 273 may repeat on / off every 10 seconds.

Then, the temperature change amount of the freezer compartment temperature Ft and the heating element temperature Ht is detected for a predetermined time to determine whether the detected temperature change amount of the freezer compartment temperature Ft and the heating element temperature Ht is less than or equal to the third reference temperature value. To judge. For example, the third reference temperature value may be 0.5 degrees, but is not limited thereto.

As shown in FIG. 11, since the blowing fan 70 is being driven, the freezer compartment temperature Ft may be gradually decreased. The temperature Ht of the heat generating element may be increased by a predetermined amount by turning on / off the heat generating element 273.

In the present embodiment, it may be determined that the detected freezer compartment temperature Ft and the change in temperature Ht of the heating element are less than the third reference temperature value as the temperature stabilization state.

On the other hand, in step S32, if the logic temperature is equal to or greater than the second reference temperature value, or in step S33, if the accumulated operating time does not reach the second reference time, the process may return to step S31.

In addition, in step S34, when the blowing fan is not driven or in step 35, the temperature stabilization state is not achieved, the process may return to step S31.

Meanwhile, in the present exemplary embodiment, a temperature difference value between the first sensing temperature Ht1 detected when the heating element 273 is turned on and the second sensing temperature Ht2 detected when the heating element 273 is turned off. Based on the above, it has been described that the amount of implantation of the evaporator 30 is detected.

However, unlike this, the temperature of the heating element is sensed while the heating element 273 is turned on, and among the sensing temperatures of the heating element, the first sensing temperature Ht1 is the lowest value and the second sensing value is the highest value. Based on the temperature difference value of the temperature Ht2, the amount of implantation of the evaporator 30 may be detected.

That is, without detecting the temperature of the heating element in the state in which the heating element 273 is turned off, the concept of the evaporator 30 is detected through the sensing temperatures Ht1 and Ht2 in the state in which the heating element 273 is on. It is possible to detect the amount.

According to the control method of the refrigerator, it is possible to accurately determine the defrosting necessary time by using a sensor whose output value varies depending on the amount of implantation of the evaporator in the bypass flow path. Therefore, when the amount of frosting is large, it is possible to quickly defrost operation, and when the amount of frosting is small, it is possible to prevent the phenomenon of defrosting.

Claims (20)

A step in which the heating element of the sensor responding to a change in flow rate of air is turned on for a predetermined time and then turned off; Detecting a first sensing temperature Ht1 of the heating element when the heating element is turned on and a second sensing temperature Ht2 of the heating element when the heating element is turned off; And And detecting an amount of implantation of the evaporator based on a temperature difference between the first sensing temperature Ht1 and the second sensing temperature Ht2. The method of claim 1, The first sensing temperature (Ht1) is a control method of the refrigerator, characterized in that the temperature detected by the sensing element of the sensor immediately after the heating element is turned on. The method of claim 1, The second sensing temperature (Ht2) is a control method of the refrigerator, characterized in that the temperature detected by the sensing element of the sensor immediately after the heating element is turned off. The method of claim 1, The first sensing temperature (Ht1) is a control method of the refrigerator, characterized in that the lowest temperature value during the time the heating element is turned on. The method of claim 1, The second sensing temperature (Ht2) is a control method of the refrigerator, characterized in that the maximum temperature value after the heating element is turned off. The method of claim 1, Determining whether a temperature difference between the first detection temperature Ht1 and the second detection temperature Ht2 is less than a first reference difference value; And If it is determined that the temperature difference between the first sensing temperature Ht1 and the second sensing temperature Ht2 is less than a first reference difference, performing a defrosting operation to remove frost generated on the surface of the evaporator. Control method of a refrigerator comprising. The method of claim 1, The heating element is a control method of the refrigerator, characterized in that turned on while the storage compartment of the refrigerator is cooled. The method of claim 1, The heating element is a control method of the refrigerator, characterized in that turned on while the blowing fan for cooling the storage compartment is driven. The method of claim 1, Determining whether the temperature difference between the first sensing temperature Ht1 and the second sensing temperature Ht2 is less than a second reference difference value when the heating element is turned off after being turned on for a predetermined time; , And the heating element is turned on according to whether the temperature difference between the first sensing temperature Ht1 and the second sensing temperature Ht2 is less than a second reference difference. The method of claim 9, When the temperature difference between the first sensing temperature Ht1 and the second sensing temperature Ht2 is less than a second reference difference, the heating element is turned on based on the accumulated cooling operation time of the storage compartment. How to control the refrigerator. The method of claim 1, The control method of the refrigerator further comprising the step of turning on the heating element, based on the cooling operation time of the accumulated storage compartment when the heating element is turned on for a predetermined time. Operating the heating element of the sensor in response to a change in the flow rate of air for a predetermined time; Sensing a temperature of the heating element while the heating element is turned on; And Among the sensing temperatures of the heating element, based on the temperature difference value of the first detection temperature (Ht1) is the lowest value, the second detection temperature (Ht2) is the maximum value, the refrigerator comprising detecting the amount of implantation of the evaporator Control method. The method of claim 12, Determining whether a temperature difference between the first detection temperature Ht1 and the second detection temperature Ht2 is less than a first reference difference value; And If it is determined that the temperature difference between the first sensing temperature Ht1 and the second sensing temperature Ht2 is less than a first reference difference, performing a defrosting operation to remove frost generated on the surface of the evaporator. Control method of a refrigerator comprising. The method of claim 12, The heating element is a control method of the refrigerator, characterized in that turned on while the storage compartment of the refrigerator is cooled. The method of claim 12, The heating element is a control method of the refrigerator, characterized in that turned on while the blowing fan for cooling the storage compartment is driven. An inner case forming a storage compartment; A cold air duct which guides the flow of air in the storage compartment and forms a heat exchange space together with the inner case; An evaporator disposed in the heat exchange space; A bypass flow passage through which air flows by bypassing the evaporator; A sensor including a heating element disposed in the bypass flow path, and a sensing element sensing a temperature of the heating element; And Based on a temperature difference value between the first sensing temperature Ht1 of the heating element detected when the heating element is turned on and the second sensing temperature Ht2 of the heating element detected when the heating element is turned off And Refrigerator comprising a control unit for detecting the amount of implantation of the evaporator. The method of claim 16, The first sensing temperature (Ht1) is a refrigerator, characterized in that the temperature detected by the sensing element immediately after the heating element is turned on. The method of claim 16, The second sensing temperature (Ht2) is a refrigerator, characterized in that the temperature detected by the sensing element immediately after the heating element is turned off. The method of claim 16, The first sensing temperature (Ht1) is a refrigerator, characterized in that the lowest temperature value during the time the heating element is turned on. The method of claim 16, The second sensing temperature (Ht2) is a refrigerator, characterized in that the highest temperature value after the heating element is turned off.

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