Refrigerator and control method thereof
阅读说明:本技术 冰箱及其控制方法 (Refrigerator and control method thereof ) 是由 崔相福 金成昱 朴景培 池成 于 2019-01-31 设计创作,主要内容包括:一种根据本发明的一个实施方式的控制冰箱的方法,该方法包括以下步骤:响应于空气流量变化的传感器的发热元件打开预定时段后关闭;在所述发热元件打开的状态下感测所述发热元件的第一感测温度(Ht1),并且在所述发热元件关闭的状态下感测所述发热元件的第二感测温度(Ht2);以及基于所述第一感测温度(Ht1)和所述第二感测温度(Ht2)之间的温度差感测蒸发器上的霜量。(A method of controlling a refrigerator according to an embodiment of the present invention includes: a heating element of the sensor responsive to the change in air flow is turned on for a predetermined period of time and then turned off; sensing a first sensed temperature (Ht1) of the heating element in a state in which the heating element is open, and sensing a second sensed temperature (Ht2) of the heating element in a state in which the heating element is closed; and sensing an amount of frost on an evaporator based on a temperature difference between the first sensed temperature (Ht1) and the second sensed temperature (Ht 2).)
1. A method of controlling a refrigerator, the method comprising:
allowing a heating element of the sensor responsive to the change in air flow to turn on for a predetermined period of time and then off;
detecting a first detection temperature (Ht1) of the heat generating element in a state where the heat generating element is turned on, and detecting a second detection temperature (Ht2) of the heat generating element in a state where the heat generating element is turned off; and
detecting an amount of frost on an evaporator based on a temperature difference between the first detected temperature (Ht1) and the second detected temperature (Ht 2).
2. The method of claim 1, wherein the first detected temperature (Ht1) is a temperature detected by a sensing element of the sensor immediately after the heating element is turned on.
3. The method of claim 1, wherein the second detected temperature (Ht2) is a temperature detected by a sensing element of the sensor immediately after the heating element is turned off.
4. The method according to claim 1, wherein the first detected temperature (Ht1) is a lowest temperature value during a period in which the heat generating element is turned on.
5. The method of claim 1, wherein the second detected temperature (Ht2) is a highest temperature value after the heating element is turned off.
6. The method of claim 1, further comprising: determining whether a temperature difference between the first detected temperature (Ht1) and the second detected temperature (Ht2) is less than a first reference difference; and
performing a defrosting operation of removing frost generated on a surface of the evaporator when it is determined that the temperature difference between the first detected temperature (Ht1) and the second detected temperature (Ht2) is less than the first reference difference.
7. The method of claim 1, wherein the heating element is turned on while cooling a storage compartment of the refrigerator.
8. The method according to claim 1, wherein the heating element is turned on while a blower for cooling the storage compartment is driven.
9. The method of claim 1, further comprising:
determining whether a temperature difference between the first detected temperature (Ht1) and the second detected temperature (Ht2) is less than a second reference difference when the heat generating element is turned on for the predetermined period of time and then turned off,
wherein whether a temperature difference between the first detected temperature (Ht1) and the second detected temperature (Ht2) is less than the second reference difference to turn on the heat generating element.
10. The method of claim 9, wherein the heating element is turned on based on a cumulative cooling operation time of the storage compartment when the temperature difference between the first detected temperature (Ht1) and the second detected temperature (Ht2) is less than the second reference difference.
11. The method of claim 1, further comprising:
when the heating element is turned on for the predetermined period of time and then turned off, the heating element is allowed to be turned on based on the accumulated cooling operation time of the storage compartment.
12. A method of controlling a refrigerator, the method comprising:
allowing a heating element of the sensor responsive to the change in the air flow rate to operate for a predetermined period of time;
detecting a temperature of the heating element while the heating element is turned on; and
the amount of frost on the evaporator is detected based on a temperature difference between a first detected temperature (Ht1) which is the lowest value and a second detected temperature (Ht2) which is the highest value among the detected temperatures of the heat generating elements.
13. The method of claim 12, further comprising:
determining whether a temperature difference between the first detected temperature (Ht1) and the second detected temperature (Ht2) is less than a first reference difference; and
performing a defrosting operation of removing frost generated on a surface of the evaporator when it is determined that the temperature difference between the first detected temperature (Ht1) and the second detected temperature (Ht2) is less than the first reference difference.
14. The method of claim 12, wherein the heating element is turned on while cooling the storage compartment of the refrigerator.
15. The method according to claim 12, wherein the heating element is turned on while a blower for cooling the storage compartment is driven.
16. A refrigerator, comprising:
an inner shell configured to define a storage space;
a cooling duct configured to guide air to flow in the storage space and to define a heat exchange space together with the inner casing;
an evaporator disposed in the heat exchange space;
a bypass passage configured to allow air to flow to bypass the evaporator;
a sensor including a heat generating element disposed in the bypass passage and a sensing element configured to detect a temperature of the heat generating element; and
a controller configured to detect an amount of frost on an evaporator based on a temperature difference between a first detected temperature (Ht1) of the heat generating element detected in a state in which the heat generating element is opened and a second detected temperature (Ht2) of the heat generating element detected in a state in which the heat generating element is closed.
17. The refrigerator of claim 16, wherein the first detected temperature (Ht1) is a temperature detected by the sensing element immediately after the heating element is turned on.
18. The refrigerator of claim 16, wherein the second detected temperature (Ht2) is a temperature detected by the sensing element immediately after the heating element is turned off.
19. The refrigerator of claim 16, wherein the first detected temperature (Ht1) is a lowest temperature value during a period in which the heat generating element is turned on.
20. The method of claim 16, wherein the second detected temperature (Ht2) is a highest temperature value after the heating element is turned off.
Technical Field
The present disclosure relates to a refrigerator and a control method thereof.
Background
A refrigerator is a home appliance capable of storing articles such as food in a storage chamber provided in a cabinet at a low temperature. Since the storage space is surrounded by the heat insulating wall, the inside of the storage space can be maintained at a temperature less than the outside temperature.
The storage space may be divided into a refrigerating storage space or a freezing storage space according to a temperature range of the storage space.
The refrigerator may further include an evaporator for supplying cool air to the storage space. The air in the storage space is cooled while flowing to the space where the evaporator is disposed, thereby exchanging heat with the evaporator, and the cooled air is supplied to the storage space again.
Here, if the air heat-exchanged with the evaporator contains moisture, the moisture freezes on the surface of the evaporator when the air heat-exchanges with the evaporator, thereby generating frost on the surface of the evaporator.
Since the flow resistance of the air acts on the frost, the more the amount of increase of the frost frozen on the evaporator surface increases, the more the flow resistance increases. As a result, heat exchange efficiency of the evaporator may be deteriorated, and thus power consumption may be increased.
Therefore, the refrigerator further includes a defroster for removing frost on the evaporator.
Korean patent laid-open publication No. 2000-0004806 (prior art document) discloses a variable defrosting cycle method.
In the prior art document, the cumulative operating time and the external temperature of the compressor are used to adjust the defrost cycle.
However, like the prior art document, when the defrosting period is determined using only the accumulated operating time of the compressor and the external temperature, the amount of frost on the evaporator (hereinafter, referred to as a frost generating amount) is not reflected. Therefore, it is difficult to accurately determine the time point at which defrosting is required.
That is, the frost generation amount may be increased or decreased according to various environments such as a user's refrigerator use mode and a degree to which air retains moisture. In the case of the prior art document, there is a disadvantage in that the defrosting cycle is determined without reflecting various environments.
Further, in the case of the prior art document, there is a disadvantage in that it is difficult to identify an exact defrosting time point since it is possible to detect a local frost amount of the evaporator and it is difficult to detect a frost amount on the entire evaporator.
Therefore, there are disadvantages in that: although a large amount of frost is generated and defrosting is not started, cooling performance is deteriorated; or starts defrosting although the amount of frost generated is low, thereby increasing power consumption due to unnecessary defrosting.
Disclosure of Invention
Technical problem
An object of the present disclosure is to provide a refrigerator and a control method thereof, which determine a time point for a defrosting operation using a parameter that varies depending on an amount of frost on an evaporator.
Further, it is an object of the present disclosure to provide a refrigerator and a control method thereof, which accurately determine a point of time at which defrosting is required according to an amount of frost on an evaporator using a sensor having an output value that is changed depending on an air flow rate.
Further, another object of the present disclosure is to provide a refrigerator and a control method thereof, which can accurately determine a time point of defrosting even in a case where the accuracy of a sensor for determining the time point of defrosting is low.
Further, it is still another object of the present disclosure to provide a refrigerator and a control method thereof, in which a detection logic for detecting an amount of frost on an evaporator can be performed at an appropriate point of time.
Further, it is still another object of the present disclosure to provide a refrigerator and a control method thereof, which improve reliability in consideration of a change of an external environment in detecting an amount of frost on an evaporator.
Technical scheme
In order to solve the above-mentioned problems, a control method of a refrigerator includes detecting an amount of frost on an evaporator based on a temperature difference between a first detected temperature (Ht1) of a heat generating element of a sensor that is detected in a state where the heat generating element is turned on and a second detected temperature (Ht2) of the heat generating element that is detected in a state where the heat generating element is turned off, the sensor being responsive to a change in an air flow rate.
As an embodiment, the first detected temperature (Ht1) may be a temperature detected by a sensing element of the sensor immediately after the heating element is turned on, and the second detected temperature (Ht2) may be a temperature detected by the sensing element of the sensor immediately after the heating element is turned off.
As an embodiment, the first detected temperature (Ht1) may be a lowest temperature value during a period in which the heat generating element is turned on, and the second detected temperature (Ht2) may be a highest temperature value after the heat generating element is turned off.
Further, when the storage compartment of the refrigerator is being cooled, the heat generating element may be in an open state. As an embodiment, the heat generating element may be in an on state while driving the blower for cooling the storage compartment.
The control method of the present disclosure may further include: determining whether a temperature difference between the first detected temperature (Ht1) and the second detected temperature (Ht2) is less than a first reference difference; and performing a defrosting operation of removing frost generated on a surface of the evaporator when it is determined that a temperature difference between the first detected temperature (Ht1) and the second detected temperature (Ht2) is less than a first reference difference.
The control method of the present disclosure may further include: when the heating element is turned on for the predetermined period of time and then turned off, it is determined whether a temperature difference between the first detected temperature (Ht1) and the second detected temperature (Ht2) is less than a second reference difference value, and the heating element may be turned on according to whether a temperature difference between the first detected temperature (Ht1) and the second detected temperature (Ht2) is less than a second reference difference value.
Opening the heat generating element based on an accumulated cooling operation time of the storage compartment when the temperature difference between the first detected temperature (Ht1) and the second detected temperature (Ht2) is less than the second reference difference value.
In order to solve the above problems, a method of controlling a refrigerator includes: the amount of frost on the evaporator is detected based on a temperature difference between a first detected temperature (Ht1) which is the lowest value and a second detected temperature (Ht2) which is the highest value among the detected temperatures of the heat generating elements.
Further, when the storage compartment of the refrigerator is being cooled, the heat generating element may be in an open state. As an embodiment, the heat generating element may be in an open state while driving the fan for cooling the storage compartment.
The control method of the refrigerator may further include: determining whether a temperature difference between the first detected temperature (Ht1) and a second detected temperature (Ht2) is less than a first reference difference value; and performing a defrosting operation of removing frost generated on a surface of the evaporator when it is determined that a temperature difference between the first detected temperature (Ht1) and the second detected temperature (Ht2) is less than a first reference difference.
In order to solve the above problems, a refrigerator may include: a heating element; a sensor including a sensing element that detects a temperature of the heat generating element; and a controller that detects an amount of frost on the evaporator based on a temperature difference between a first detected temperature (Ht1) of the heat generating element detected in a state where the heat generating element is turned on and a second detected temperature (Ht2) of the heat generating element detected in a state where the heat generating element is turned off.
Advantageous effects
According to the proposed invention, since the point of time at which defrosting is required is determined using the sensor having the output value changed according to the amount of frost generated on the evaporator in the bypass passage, the point of time at which defrosting is required can be accurately determined.
Further, even in the case where the accuracy of the sensor for determining the time point of defrosting is low, the time point of defrosting can be accurately determined, thereby significantly reducing the cost of the sensor.
Further, since the detection logic for detecting the amount of frost on the evaporator can be performed at an appropriate point in time, power consumption is reduced and convenience is improved.
In addition, since a change in an external environment (e.g., an internal refrigerator load) is taken into consideration in detecting the amount of frost on the evaporator, product reliability is improved.
Drawings
Fig. 1 is a schematic longitudinal sectional view of a refrigerator according to one embodiment of the present invention.
Fig. 2 is a perspective view of a cool air duct according to an embodiment of the present invention.
Fig. 3 is an exploded perspective view illustrating a state in which a channel cover and a sensor are separated from each other in a cool air duct.
Fig. 4 is a view illustrating air flows in the heat exchange space and the bypass passage before and after frost is generated.
Fig. 5 is a schematic view showing a state in which the sensor is arranged in the bypass passage.
FIG. 6 is a view of a sensor according to an embodiment of the present invention.
Fig. 7 is a view showing heat flow around the sensor depending on the air flow flowing through the bypass passage.
Fig. 8 is a control block diagram of a refrigerator according to one embodiment of the present disclosure.
Fig. 9 is a flowchart illustrating a control method for detecting the amount of frost on an evaporator according to one embodiment of the present disclosure.
Fig. 10 is a flowchart illustrating a method of performing a defrosting operation by determining a time point at which a refrigerator needs to be defrosted according to an embodiment of the present disclosure.
Fig. 11 is a view illustrating a temperature change of a heat generating element according to turning on/off of the heat generating element before and after frost is formed on an evaporator according to an embodiment of the present disclosure.
Fig. 12 is a flowchart illustrating a control method for determining an operation time point of a heat generating element according to one embodiment of the present disclosure.
Detailed Description
Hereinafter, some embodiments of the present invention will be described in detail with reference to the accompanying drawings. Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Note that, even if the same or similar components in the drawings are shown in different drawings, the same reference numerals are used to designate the components as much as possible. Further, in the description of the embodiments of the present disclosure, when it is determined that a detailed description of a well-known configuration or function interferes with understanding of the embodiments of the present disclosure, the detailed description will be omitted.
Further, in the description of the embodiments of the present disclosure, terms such as first, second, A, B, (a) and (b) may be used. Each term is used only to distinguish the corresponding component from other components and does not define the nature, order, or sequence of the corresponding components. It will be understood that when an element is "connected," "coupled," or "engaged" to another element, the former may be directly connected or engaged to the latter, or the latter may be "connected," "coupled," or "engaged" to the other element with a third element interposed therebetween.
Fig. 1 is a schematic longitudinal sectional view of a refrigerator according to one embodiment of the present invention, fig. 2 is a perspective view of a cool air duct according to one embodiment of the present invention, and fig. 3 is an exploded perspective view illustrating a state in which a channel cover and a sensor are separated from each other in the cool air duct.
Referring to fig. 1 to 3, a
The storage space may include one or more of a refrigerated storage space and a frozen storage space.
The
Accordingly, the air of the
The
The front surface of the
In a state where the
In addition, the
A blower (not shown) may be provided in the
The
Accordingly, the air in the
According to this arrangement, when the amount of frost generated on the
In this embodiment, a parameter that varies according to the amount of frost generated on the
For example, the
The frost generating sensing part may include: a
Although not limited, the
The
The
The
The frost generating sensing portion may further include a
The
The
Fig. 4 is a view illustrating air flows in the heat exchange space and the bypass passage before and after frost is generated.
Fig. 4 (a) shows the flow of air before frost is generated, and fig. 4 (b) shows the flow of air after frost is generated. In the present embodiment, as an example, a state after completion of the defrosting operation is assumed as a state before frost is generated.
First, referring to (a) of fig. 4, in the case where there is no frost on the
Referring to (b) of fig. 4, when the amount of frost generated on the
As described above, the amount (or flow rate) of air flowing through the
In this embodiment, the
Hereinafter, the structure and principle of the
Fig. 5 is a schematic view showing a state in which a sensor is disposed in a bypass passage, fig. 6 is a view of the sensor according to one embodiment of the present invention, and fig. 7 is a view showing heat flow around the sensor depending on air flow flowing through the bypass passage.
Referring to fig. 5-7, the
The
Since the
The
The
The
When the flow rate of the air flowing through the
On the other hand, if the flow rate of the air flowing through the
The
The
For example, referring to fig. 4 and 7, when the amount of frost generated on the
On the other hand, when the amount of frost generated on the
Therefore, the temperature sensed by the
Therefore, in the present embodiment, when the difference between the temperature sensed by the
According to this embodiment, the
The
The
Fig. 8 is a control block diagram of a refrigerator according to one embodiment of the present disclosure.
Referring to fig. 8, a
The defrosting device 50 may include, for example, a heater. When the heater is turned on, heat generated by the heater is transferred to the
The
Further, the low-temperature and low-pressure two-phase refrigerant is evaporated into a low-temperature and low-pressure gaseous refrigerant while passing through the
The blower 70 is disposed in the
The controller 40 may control the
To determine when defrosting is required, the
After the
Further, when the maximum value of the temperature difference between the on/off states of the
Although it has been described above that the
Hereinafter, a method for detecting the amount of frost on the
Fig. 9 is a flowchart illustrating a control method for detecting the amount of frost on an evaporator according to one embodiment of the present disclosure. In the present embodiment, a method for detecting the amount of frost on the
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 a state where a cooling operation of the storage compartment 11 (e.g., a freezing compartment) is performed.
Here, the state in which the cooling operation of the freezing chamber is performed may refer to a state in which the
As described above, when the variation in the flow rate of air increases with the amount of frost on the
Therefore, the accuracy of the sensor can be improved only when frost on the
Next, in step S13, when the
Specifically, the
As the period of time for which the
On the other hand, when the amount of frost on the
On the other hand, when the amount of frost on the
In the present embodiment, the temperature of the
Next, in step S15, after a predetermined period of time has elapsed, the
As an example, the
When the
As the period during which the
Next, in step S17, the temperature of the
Specifically, the temperature of the
In the present embodiment, the temperature of the
Next, in step S19, the amount of frost on the
As described above, when the amount of frost on the
In contrast, when the amount of frost on the
As described above, by detecting the lowest temperature value and the highest temperature value when the
In summary, when the temperature difference between the lowest temperature value and the highest temperature value of the
Hereinafter, a detailed method for detecting the amount of frost on the above-described
Fig. 10 is a flowchart illustrating a method of performing a defrosting operation by determining a time point at which a refrigerator needs to be defrosted according to an embodiment of the present disclosure, and fig. 11 is a view illustrating a temperature change of a heating element according to turning on/off of the heating element before and after frost is formed on an evaporator according to an embodiment of the present disclosure.
Fig. 11 (a) shows a temperature change of the freezing chamber and a temperature change of the heat generating element before frost occurs on the
Referring to fig. 10 and 11, in step S21, the heat generating element 27 is turned on.
Specifically, the
As an example, as shown in fig. 11, in the case where the blower 70 is driven, the
The blower 70 may be driven for a predetermined period of time to cool the freezing chamber. In this case, the
On the other hand, when the
Next, in step S22, it may be determined whether the blower 70 is turned on.
As described above, the
When the blower 70 is driven, in step S23, the temperature Htl of the heat generating element may be detected.
Specifically, the
In the present embodiment, the temperature Ht1 of the
Here, the temperature of the
Next, in step S24, it is determined whether the first reference time T1 has elapsed while the
While the
Here, the first reference time T1 for maintaining the
When the predetermined period of time has elapsed while the
As shown in fig. 11, the
However, when the off state of the
Next, in step S26, the temperature Ht2 of the heat generating element may be detected.
That is, the temperature Ht2 of the heater element is detected by the
In the present embodiment, the temperature Ht2 of the heater element may be detected at the time point when the
Here, the temperature of the
In summary, the temperature Ht of the heater element may be first detected at a time point S1 when the
Next, in step S27, it is determined whether a temperature steady state has been reached.
Here, the temperature stable state may refer to a state in which the load of the internal refrigerator does not occur, that is, a state in which the cooling of the storage compartment is normally performed. In other words, being in a temperature stable state may mean that the opening/closing operation of the refrigerator door is not performed, or that there is no defect in the
That is, the
In the present embodiment, in order to determine that the temperature steady state is reached, the amount of temperature change of the freezing chamber in a predetermined period of time may be determined. Alternatively, in order to determine that the temperature steady state is reached, the amount of temperature change of the
For example, a state in which the temperature of the freezing chamber or the temperature of the
As described above, the temperature Ht of the heat generating element may be rapidly decreased immediately after the
When the temperature steady state is reached, in step S28, a temperature difference Δ Ht between the temperature Ht1 detected when the
In step S29, it is determined whether the temperature difference Δ Ht is smaller than a first reference temperature value.
Specifically, when the amount of frost on the
As a result, when the amount of frost on the
Next, when the temperature difference Δ Ht is smaller than the first reference temperature value, in step S30, a defrosting operation is performed.
When the defrosting operation is performed, the defrosting device 50 is driven, and the heat generated by the heater is transferred to the
On the other hand, when the temperature steady state is not reached in step S27, or when the temperature difference Δ Ht is greater than or equal to the first reference temperature value in step S29, the algorithm ends without performing the defrosting operation.
In the present embodiment, the temperature difference Δ Ht may be defined as a "logical temperature" for detecting frosting. The logic temperature may be used as a temperature for determining a time point of a defrosting operation of the refrigerator, and may be used as a temperature for determining a time point at which the
Fig. 12 is a flowchart illustrating a control method for determining an operation time point of a heat generating element according to one embodiment of the present disclosure. The present embodiment may be understood as a control method for determining the point in time at which the heating element 373 is turned on (step S21) in fig. 10.
Referring to fig. 11 and 12 together, in step S31, the heating element 27 may be turned off. Here, step S31 may refer to 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, in step S32, it is determined whether the logic temperature Δ Ht is less than the second reference temperature value.
It is possible to detect the amount of frost on the
For example, the second reference temperature value may be 35 degrees.
Specifically, in fig. 10, it has been described that the first reference temperature value for performing the defrosting operation is 32 degrees. In this case, the second reference temperature value may be set to be greater than the first reference temperature value. That is, even when the defrosting operation is completed, the amount of frost on the
When the logic temperature Δ Ht is less than the second reference temperature value, it is determined whether the accumulated operating time of the freezing compartment has reached the second reference time in step S33. Here, the second reference time may be, for example, 1 hour.
Next, when the logic temperature Δ Ht is less than the second reference temperature value, it may be determined whether the blower 70 is being driven in step S34.
When the blower 70 is driven, it is determined whether the temperature stable state is reached in step S35, and when the temperature stable state is reached, the
Here, the temperature stable state may refer to a state in which the load of the internal refrigerator does not occur or a state in which the cooling of the storage compartment is normally performed. In other words, being in a temperature stable state may mean that the opening/closing operation of the refrigerator door is not performed, or that there is no defect in the
In the present embodiment, in order to determine the temperature stable state, the
That is, the
Further, it is determined whether the detected temperature variation of the freezing chamber temperature (Ft) and the temperature variation of the heating element temperature (Ht) are less than a third reference temperature value by detecting the temperature variation of the freezing chamber temperature (Ft) or the heating element temperature (Ht) for a predetermined period of time. For example, the third reference temperature value may be 0.5 degrees, but is not limited thereto.
As shown in fig. 11, since the blower fan 70 is driven, the temperature Ft of the freezing chamber may be gradually decreased. In addition, by turning on/off the
In the present embodiment, a case where the detected variation amount of the temperature (Ft) of the freezing compartment and the detected variation amount of the temperature (Ht) of the heating element are less than the third reference temperature value may be determined as the temperature stable state.
On the other hand, when the logic temperature is equal to or higher than the second reference temperature value in step S32, or when the accumulated operating time does not reach the second reference time in step S33, the process returns to step S31.
Further, when the blower is not driven in step S34, or when the temperature stable state is not reached in step S35, the process returns to step S31.
Meanwhile, in the present embodiment, it is described that the amount of frost on the
However, alternatively, the temperature of the heating element may be detected in a state where the
That is, the amount of frost on the
According to the method of controlling the refrigerator, a point of time at which defrosting is required can be accurately determined using a sensor in the bypass passage having an output value that varies according to the amount of frost on the evaporator. Therefore, when the amount of frost is large, a quick defrosting operation can be performed, and when the amount of frost is small, a phenomenon that defrosting is started can be prevented.