Refrigerator and control method thereof

Abstract

The invention relates to a refrigerator and a control method thereof. The present invention provides a method for controlling a refrigerator, comprising: a first step of heating an evaporator by continuously operating a heater, the heater supplying heat to the evaporator, and the evaporator supplying cold air to a storage chamber; secondly, whether the time for the evaporator to reach the set temperature is within the set time or not is judged; and in the second step, when it is determined that the heater is not within the set time, continuously operating the heater in the same manner as the first step, and in the second step, when it is determined that the heater is within the set time, operating the heater in a different manner from the first step.

Description

[0001] This case is a divisional application of a patent application for an invention titled "Refrigerator and Its Control Method" with an application date of April 10, 2018, an application number of 201810315404.8. Technical Field

[0002] The present invention relates to a refrigerator and its control method. More specifically, it relates to a refrigerator and its control method for improving the reliability of defrosting or energy efficiency. Background Art

[0003] Generally, a refrigerator includes a mechanical chamber formed at the lower part of the main body. To lower the center of gravity of the refrigerator, improve the assembly efficiency, and reduce vibration, the mechanical chamber is usually provided at the lower part of the refrigerator.

[0004] A refrigeration cycle device is provided in the mechanical chamber of such a refrigerator. Utilizing the property that when a low-pressure liquid refrigerant changes to a gaseous refrigerant, it absorbs external heat to maintain the frozen / cooled state, thereby storing food fresh.

[0005] The refrigeration cycle device of the refrigerator includes: a compressor that converts a low-temperature and low-pressure gaseous refrigerant into a high-temperature and high-pressure gaseous refrigerant; a condenser that converts the high-temperature and high-pressure gaseous refrigerant converted in the compressor into a low-temperature and high-pressure liquid refrigerant; and an evaporator that converts the low-temperature and high-pressure liquid refrigerant converted in the condenser into a gas while absorbing external heat. Generally, the evaporator is arranged in an independent space rather than in the mechanical chamber to be separated from other refrigeration cycle devices.

[0006] The evaporator supplies cold air to the storage chamber and exchanges heat with the internal air of the storage chamber. Over time, ice forms on the evaporator due to frosting. To remove the frosted ice, the heater can be operated periodically, but frequently operating the heater consumes energy. In addition, the heat generated by the heater raises the internal temperature of the storage chamber, thus there is a concern about food spoilage. In addition, to lower the temperature raised by the heater, more compressors need to be operated, thus there is a problem of increasing the energy consumption of the compressor.

[0007] Therefore, it is necessary to improve the reliability of removing the ice frosted on the evaporator and reduce the energy used, thereby reducing the energy consumption of the refrigerator. Summary of the Invention

[0008] The present invention provides a high-energy-efficiency refrigerator and its control method.

[0009] In addition, the present invention provides a refrigerator and its control method that can prevent the temperature of the storage chamber from rising sharply when defrosting the evaporator.

[0010] In addition, the present invention provides a refrigerator and a control method thereof that can improve the reliability of defrosting. That is, according to the present invention, the probability of removing the ice formed on the evaporator can be increased.

[0011] To achieve the above object, the present invention provides a control method for a refrigerator, characterized by comprising: a first step of heating the evaporator by continuously operating a heater that supplies heat to the evaporator, and the evaporator supplies cold air to the storage chamber; a second step of determining whether the time for the evaporator to reach a set temperature is within a set time; and in the second step, when it is determined that the time is not within the set time, continuously operating the heater in the same manner as in the first step, and in the second step, when it is determined that the time is within the set time, operating the heater differently from the first step.

[0012] In the third step, even if no current is supplied to the heater, the heater still has residual heat.

[0013] In the second step, determine the amount of frost formed on the ice remaining on the evaporator.

[0014] It further includes a step of determining the start of defrosting, in which it is determined whether the conditions for starting the first step are satisfied.

[0015] In the second step, determine whether the time from the start time point of the first step to the time point when the set temperature is reached is within the set time.

[0016] When the third step ends, the defrosting of the evaporator ends.

[0017] In the first step, a fixed input value is provided to the heater.

[0018] In addition, the present invention provides a refrigerator, characterized by comprising: an evaporator that supplies cold air to the storage chamber; an evaporator temperature sensor that measures the temperature of the evaporator; a timer that measures the elapsed time; a heater that supplies heat to the evaporator; and a control unit that controls the heater. After starting to operate the heater, the control unit determines whether the time for the evaporator to reach a set temperature is within a set time. When it is not within the set time, the heater is operated in the same manner as before. When it is within the set time, the heater is operated differently from before.

[0019] It further includes a compressor that supplies compressed refrigerant to the evaporator, and the compressor does not operate during the operation of the heater.

[0020] When it is within the set time, the control unit operates the heater to repeatedly turn the heater on / off.

[0021] It also includes a fan for supplying the cold air generated by the evaporator to the storage chamber, and the fan is not operated during the operation of the heater.

[0022] When it is determined that it is within the set time, the supply / non - supply of current to the heater is repeated.

[0023] According to the present invention, defrosting is performed on the evaporator and the remaining amount of ice is determined. When the remaining amount is large, more heat can be applied through the heater; when the remaining amount is small, less heat can be applied through the heater. Therefore, by comparing the remaining amount of ice, excessive heat supply can be prevented through the heater, and the power consumption of the refrigerator can be reduced.

[0024] In addition, since heat is supplied by judging the remaining amount of ice, the probability of remaining ice in the evaporator can be reduced, thereby improving the reliability of defrosting.

[0025] In addition, the heat supplied to the evaporator can be reduced, preventing the temperature in the storage chamber from rising sharply, thereby preventing the food stored in the storage chamber from spoiling. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a front view of the door of the refrigerator according to an embodiment of the present invention being opened.

[0027] Figure 2A 、 Figure 2B is a diagram showing a refrigeration cycle to which the embodiment of the present invention can be applied.

[0028] Figure 3 is a control block diagram according to an embodiment of the present invention.

[0029] Figure 4 is a diagram for explaining the chamber provided with the evaporator.

[0030] Figure 5 is a diagram for explaining the defrosting process of the evaporator according to the present invention.

[0031] Figure 6 is a diagram for explaining the time point of defrosting.

[0032] Figure 7 is a diagram for explaining the heater control of an embodiment of the present invention.

[0033] Figure 8 is a diagram for explaining the heater control of another embodiment.

[0034] Figure 9 is a diagram for explaining the heater control of still another embodiment.

[0035] Figure 10It is a diagram for explaining the heater control of another embodiment.

[0036] Figure 11 It is a diagram for explaining the heater control of another embodiment.

[0037] Figure 12 It is a diagram for explaining the heater control of another embodiment.

[0038] Figure 13 It is a diagram for explaining the heater control of another embodiment.

[0039] Figure 14 It is a diagram for explaining the heater control of another embodiment.

[0040] Figure 15A 、 Figure 15B It is a diagram for explaining the heater control of another embodiment.

[0041] Figure 16 It is a diagram for explaining the heater control of another embodiment.

[0042] Description of Reference Numerals

[0043] 110, 112: Compressor 120: Condenser

[0044] 130: Expansion Valve 150: Refrigerator Compartment Evaporator

[0045] 160: Freezer Compartment Evaporator 170: Heater

[0046] 180: Fan 192: Storage Compartment Temperature Sensor

[0047] 194: Evaporator Temperature Sensor 200: Control Unit Detailed Description of the Invention

[0048] Generally, a refrigerator forms a food storage space that can block heat entering from the outside with a cabinet and a door filled with heat insulating material inside, and is provided with a refrigeration device composed of an evaporator that absorbs the heat inside the food storage space and a heat dissipation device that discharges the heat collected outside the food storage space, and maintains the food storage space at a low temperature region where it is difficult for microorganisms to survive and proliferate, so that the stored food can be stored without changing its texture for a long time.

[0049] The refrigerator can be formed by separating a refrigerating compartment for storing food in a temperature region above zero and a freezing compartment for storing food in a temperature region below zero. According to the configurations of the refrigerating compartment and the freezing compartment, the refrigerator is classified into a top freezer refrigerator with an upper freezing compartment and a lower refrigerating compartment, a bottom freezer refrigerator with a lower freezing compartment and an upper refrigerating compartment, and a side by side refrigerator with a left freezing compartment and a right refrigerating compartment, etc.

[0050] Moreover, in order to enable users to conveniently store food in the food storage space or take out the food stored in the food storage space, a plurality of shelves, drawers, etc. are provided inside the food storage space.

[0051] Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention that can specifically achieve the above object will be described.

[0052] In this process, for the sake of clarity and convenience of description, the sizes, shapes, etc. of the elements shown in the drawings may be exaggeratedly shown. In addition, considering the structure and function of the present invention, specially defined terms may be changed according to the intention of the user, operator or conventional practice. The definitions of such terms should be determined based on the entire content of this specification.

[0053] Figure 1 It is a front view of the door of the refrigerator according to an embodiment of the present invention being opened.

[0054] The refrigerator according to the embodiment is not only applicable to a top mount - type refrigerator in which the freezing compartment and the refrigerating compartment for storing food are divided above / below, and the freezing compartment is arranged above the refrigerating compartment, but also applicable to a side by side - type refrigerator in which the freezing compartment and the refrigerating compartment are divided left / right.

[0055] However, in this embodiment, for the sake of convenience of description, a bottom freezer - type in which the freezing compartment and the refrigerating compartment are divided above / below and the freezing compartment is arranged below the refrigerating compartment will be mainly described.

[0056] The cabinet of the refrigerator includes: an outer shell 10 that forms the overall appearance when observed by the user from the outside; an inner shell 12 that forms a storage chamber 22 for storing food inside. A passage for circulating cold air may be formed between the outer shell 10 and the inner shell 12 to form a specified space. Moreover, a heat - insulating material is filled between the outer shell 10 and the inner shell 12, whereby the interior of the storage chamber 22 can be maintained at a relatively lower temperature than the outside.

[0057] In addition, a refrigerant circulation device that circulates refrigerant to generate cold air is provided in a mechanical room (not shown) formed in the space between the outer shell 10 and the inner shell 12. The refrigerant circulation device is used to keep the inside of the refrigerator at a low temperature, thereby maintaining the freshness of the stored food. The refrigerant circulation device includes a compressor that compresses the refrigerant, an evaporator (not shown) that converts the liquid refrigerant into a gaseous state to form a heat exchange with the outside, etc. In this case, the evaporator is provided in an independent chamber, not in the mechanical room.

[0058] The refrigerator is provided with doors 20 and 30 to open / close the storage chamber. In this case, the doors may include a freezer door 30 and a refrigerator door 20, and one end of each door may be rotatably provided on the cabinet of the refrigerator by a hinge. The freezer door 30 and the refrigerator door 20 may be formed in plurality. Figure 1 As shown, the refrigerator door 20 and the freezer door 30 may be arranged to face forward and open around two corners of the refrigerator.

[0059] A foaming agent is filled between the outer shell 10 and the inner shell 12 , so that the outside and the storage chamber 22 are thermally insulated.

[0060] The storage chamber 22 is formed as a space insulated from the outside by the inner shell 12 and the door 20. When the door 20 closes the storage chamber 22, the storage chamber 22 can form a space insulated from the outside. In other words, the storage chamber 22 can be called a space insulated from the outside by the insulation wall of the door 20 and the insulation walls of the shells 10 and 12.

[0061] The cold air supplied from the machine room can flow to various places in the storage chamber 22, so that the food stored in the storage chamber 22 can be kept at a low temperature.

[0062] The storage chamber 22 may include a shelf 40 on which food is placed. In this case, a plurality of shelves 40 are provided, and food may be placed on each shelf 40. The shelf 40 may divide the interior of the storage chamber in a horizontal direction.

[0063] The storage chamber 22 is provided with a drawer 50 that can be pushed in or pulled out. The drawer 50 accommodates and stores food and the like. Two drawers 50 can be arranged on the left and right sides of the storage chamber 22. To approach the drawer arranged on the left, the user can open the left door of the storage chamber 22. On the other hand, to approach the drawer arranged on the right, the user can open the right door of the storage chamber 22.

[0064] The storage chamber 22 is divided into a space located on the upper side of the shelf 40, a space formed by the drawer 50, etc., so that the space for storing food can be divided into a plurality of spaces.

[0065] Although the cold air supplied to a storage chamber cannot freely move to other storage chambers, the cold air supplied to a storage chamber can freely move to each space divided inside this storage chamber. That is, the cold air located above the shelf 40 can move to the space formed by the drawer 50.

[0066] FIG. 2 is a diagram showing a refrigeration cycle to which an embodiment of the present invention can be applied.

[0067] In Figure 2A a compressor 110, a condenser 120, an expansion valve 130, and evaporators 150 and 160 are provided. The compressor 110 compresses the refrigerant, the compressed refrigerant exchanges heat in the condenser 120 and is cooled, the refrigerant vaporizes in the expansion valve 130, and the refrigerant exchanges heat with air in the evaporators 150 and 160. At this time, when the air cooled in the evaporators 150 and 160 is supplied to the storage chamber 22, the temperature of the storage chamber 22 can be lowered.

[0068] The refrigerant compressed by the compressor 110 is determined whether to be guided to the evaporator 150 or the evaporator 160 through the valve 140. That is, the evaporator 150 can be a refrigerating chamber evaporator for supplying cold air to the refrigerating chamber. The evaporator 160 can be a freezing chamber evaporator for supplying cold air to the freezing chamber.

[0069] When the refrigerant compressed by the compressor 110 is supplied to the refrigerating chamber evaporator 150, the cold air that exchanges heat with the refrigerating chamber evaporator 150 is supplied to the refrigerating chamber and the refrigerating chamber can be cooled.

[0070] On the other hand, when the refrigerant compressed by the compressor 110 is supplied to the freezing chamber evaporator 160, the cold air that exchanges heat with the freezing chamber evaporator 160 is supplied to the freezing chamber and the freezing chamber can be cooled.

[0071] In Figure 2A the embodiment, the refrigerant compressed by one compressor 110 is selectively supplied to the refrigerating chamber evaporator 150 or the freezing chamber evaporator 160, so that each evaporator can be cooled and each storage chamber can be cooled.

[0072] In Figure 2B the embodiment, different from Figure 2A that, two compressors are provided. The compressor 110 supplies the compressed refrigerant to the refrigerating chamber evaporator 150, and the compressor 112 supplies the compressed refrigerant to the freezing chamber evaporator 160.

[0073] Figure 2B Different from Figure 2ADifferent, there is no need to configure the valves for changing the flow path of the refrigerant compressed by the compressors 110 and 112. Instead, a condenser 120 and an expansion valve 130 for supplying cold air to the refrigerating chamber are provided, and a condenser 122 and an expansion valve 132 for supplying cold air to the freezing chamber are provided.

[0074] In Figure 2B There are two compressors 110 and 112 provided, so that the refrigerating chamber and the freezing chamber can be cooled simultaneously.

[0075] Figure 3 is a control block diagram according to an embodiment of the present invention.

[0076] In an embodiment of the present invention, a storage chamber temperature sensor 192 for measuring the temperature of the storage chamber is included. The storage chamber temperature sensor 192 can measure the temperature inside the refrigerating chamber or the freezing chamber.

[0077] In addition, an embodiment of the present invention includes an evaporator temperature sensor 194 for measuring the temperature of the evaporator. The evaporator temperature sensor 194 can measure the temperature of the evaporator in the refrigerating chamber or the freezing chamber.

[0078] The temperatures measured by the storage chamber temperature sensor 192 and the evaporator temperature sensor 194 can be transmitted to the control unit 200.

[0079] In addition, an embodiment of the present invention is provided with a door switch 196 for judging whether the doors 20 and 30 are opened / closed. The door switch 196 is respectively provided on each door, so as to sense whether the freezing chamber door or the refrigerating chamber door is opened or closed respectively.

[0080] In addition, an embodiment of the present invention is provided with a timer 198 for measuring the elapsed time. The time measured by the timer 198 is transmitted to the control unit 200, so as to perform control according to the measured time.

[0081] In an embodiment of the present invention, a control unit 200 is included, which performs control according to the information conveyed by the storage chamber temperature sensor 192, the evaporator temperature sensor 194, the timer 198, and the door switch 196.

[0082] In an embodiment of the present invention, a heater 170 may also be included, which supplies heat to the freezing chamber evaporator 160 or the refrigerating chamber evaporator 150, so as to remove the ice frosted on the freezing chamber evaporator 160 or the refrigerating chamber evaporator 150. The heater 170 may also be provided with only one on the freezing chamber evaporator 160, or may be provided on both the freezing chamber evaporator 160 and the refrigerating chamber evaporator 150 respectively. In addition, multiple heaters may be provided on the freezing chamber evaporator 160 or the refrigerating chamber evaporator 150 respectively.

[0083] The present invention includes: compressors 110, 112 that supply compressed refrigerant to the refrigerating chamber evaporator or the freezing chamber evaporator; and a fan 180 that supplies the cold air generated by the evaporators 150, 160 to the storage chamber. The fan 180 may be respectively disposed at the freezing chamber evaporator 160 and the refrigerating chamber evaporator 150.

[0084] The control unit 200 may control the compressors 110, 112 and the refrigerating chamber fan 180 according to the temperatures measured by the evaporator temperature sensor 194 and the refrigerating chamber temperature sensor 192.

[0085] Figure 4 It is a diagram for explaining a chamber provided with an evaporator.

[0086] The evaporator temperature sensor 194 is disposed inside the chamber provided with the evaporators 150, 160, so as to measure the temperatures of the evaporators 150, 160.

[0087] As Figure 4 shown, the evaporator temperature sensor 194 may be disposed at a pipe near the inlet where refrigerant flows into the evaporators 150, 160.

[0088] The evaporators 150, 160 have a pipe shape that is integrally connected and is bent in a zigzag pattern, and are provided with a plurality of fin portions for increasing the heat exchange area. After passing through the expansion valve, the refrigerant is supplied to the evaporators 150, 160.

[0089] The evaporator temperature sensor 194 may be disposed at the front end of the portion forming the fin portions of the evaporators 150, 160, that is, may be located at a position where the refrigerant arrives before reaching the position where the fin portions of the refrigerating chamber evaporator 150 are located.

[0090] Generally, the temperature of the portion near the inlets of the evaporators 150, 160 is lower than that of other portions. This is because when the refrigerant flows into the evaporators 150, 160, the evaporators 150, 160 exchange heat with the external air, but the portion corresponding to the inlet is generally in a state where there is no significant heat exchange with the outside.

[0091] The portion where the temperature of the evaporators 150, 160 is the lowest may be the portion where ice condenses and frost is likely to form. Therefore, the evaporator temperature sensor 194 is arranged at a portion where the temperature of the evaporators 150, 160 is relatively low or where frost is relatively likely to form, so as to measure the temperatures of the evaporators 150, 160.

[0092] In addition, the heater 170 that supplies heat to the evaporators 150 and 160 may include a plurality of heaters 172 and 174. One of the heaters 170 may include a sheathed heater, a wire heater, and the like.

[0093] For example, the heater 172 may be configured as a sheathed heater at the lower part of the evaporators 150 and 160. The heaters 172 are arranged at intervals at the lower part of the evaporators 150 and 160, and the air heated by the heaters 172 rises to the evaporators 150 and 160, and heat may be supplied to the evaporators 150 and 160 by means of convection or the like.

[0094] In addition, the heater 174 may be configured as a wire heater and connected to the evaporators 150 and 160 on the upper side of the evaporators 150 and 160, and the heat of the heater 174 may be transferred to the evaporators 150 and 160 by conduction. Therefore, the evaporators 150 and 160 heat and melt the ice that has frosted on the evaporators 150 and 160, and the melted ice may fall to the lower part of the evaporators 150 and 160.

[0095] The heaters 172 and 174 are independent elements. When one heater operates and supplies heat, the other heater may not operate. Of course, both heaters may also operate and supply heat together.

[0096] Figure 5 It is a diagram for explaining the defrosting process of the evaporator according to the present invention.

[0097] The compressors 110 and 112 operate, so that the compressed refrigerant can move to the evaporators 150 and 160. At this time, the fan 180 operates, and the air cooled by the evaporator moves to the storage chamber, thereby cooling the storage chamber.

[0098] When the operating time of the refrigerator increases, ice may frost on the evaporators 150 and 160.

[0099] S10: Determine whether the defrost start condition of the refrigerator is satisfied.

[0100] The defrost start condition may refer to the time point when too much ice has frosted on the evaporators 150 and 160, resulting in a reduction in the heat exchange efficiency of the evaporators.

[0101] S20: When it is determined that the defrost start condition is satisfied, operate the heater 170. Supply current to the heater 170, and the heater 170 can generate heat.

[0102] The heat generated by the heater 170 is transferred to the evaporators 150 and 160 by convection, conduction, or the like to heat the evaporators 150 and 160, so that the ice frosted on the evaporators 150 and 160 starts to melt.

[0103] The evaporator temperature sensors 194 can measure the temperatures of the evaporators 150 and 160. While the heater 170 is operating, the temperatures of the evaporators 150 and 160 can be measured.

[0104] S30: Determine whether the temperature measured by the evaporator temperature sensor 194 reaches a first set temperature.

[0105] The first set temperature can be set differently. However, it can also be roughly predetermined as minus 5 degrees Celsius.

[0106] S40: When the evaporators 150 and 160 reach the first set temperature, determine whether the time required to reach the first set temperature is within a set time.

[0107] The timer 198 measures the time required from the time point when the heater 170 starts operating to satisfy the defrost start condition to reach the first set temperature, and the corresponding information can be transmitted to the control unit 200 described above.

[0108] When the first set temperature is reached within the set time, it can be predicted that there is not much remaining ice on the evaporators 150 and 160. On the other hand, when the first set temperature is not reached within the set time, it can be predicted that there is a lot of remaining ice on the evaporators 150 and 160.

[0109] Even if the same amount of heat is supplied by the heater 170, the temperature rises slowly because there is a large amount of ice frosted on the evaporators 150 and 160, so it takes a long time to defrost. On the other hand, the temperature of the evaporators 150 and 160 rises quickly because there is a small amount of ice frosted on the evaporators 150 and 160, which means that even if the heater is operated relatively less, the ice can be simply removed.

[0110] S50: When it is determined that it is within the set time, the control unit 200 operates the heater 170 in a second mode.

[0111] On the other hand, S60: When it is determined that it is not within the set time, the control unit 200 operates the heater 170 in a first mode.

[0112] At this time, the first mode and the second mode may be different from each other in the way of operating the heater, for example, the duty ratio of on / off, the cycle of on / off, the input value supplied to the heater, etc.

[0113] That is, in the present invention, after defrosting starts, according to the time required to reach a specific temperature, the heater is then controlled to operate differently. Thus, it is possible to prevent the temperature of the storage chamber from rising due to excessive heat generated by the heater or to prevent energy waste due to excessive current supplied to the heater.

[0114] In addition, in the present invention, in the case where the thermal efficiency of the evaporator is reduced due to a large amount of remaining ice on the evaporator, a large amount of heat can be supplied through the heater to remove the remaining ice on the evaporator. Thus, the reliability of defrosting of the evaporator can be improved.

[0115] After the heater is operated through S60 and S50, S70: When the defrost end condition is satisfied, defrosting can be ended.

[0116] At this time, the defrost end condition may refer to the temperature of the evaporators 150 and 160 reaching a second set temperature higher than the first set temperature. For example, the second set temperature may refer to a temperature one degree Celsius above zero higher than the first set temperature. The second set temperature can be variously changed by the user, but is preferably predetermined to be higher than the first set temperature.

[0117] In addition, in order to defrost the evaporators 150 and 160, during the operation of the heater 170, the compressors 110 and 112 are in a non-operating and stationary state.

[0118] In addition, during the operation of the heater 170, the fan 180 preferably remains in a non-operating and stationary state so that the air heated by the heater 170 is not guided to the storage chamber by the fan 180.

[0119] Figure 6 It is a diagram for explaining the time point of performing defrosting.

[0120] In an embodiment of the present invention, the time point for defrosting the freezer evaporator and the time point for defrosting the refrigerator evaporator may be the same. On the other hand, they may also be independent of each other.

[0121] That is, when defrosting the freezer evaporator, the refrigerator evaporator can also be defrosted simultaneously. On the other hand, when the defrost start time point of the freezer evaporator is reached, the freezer evaporator can be defrosted. When the defrost condition of the refrigerator evaporator is reached, the refrigerator evaporator can be defrosted. The defrost conditions of the freezer evaporator and the refrigerator evaporator are different from each other, so that each evaporator can be defrosted only when the respective conditions are met.

[0122] First, the defrost start condition of the freezer evaporator can be based on a specific time. For example, it is based on the time point when the freezer operation time is shortened from 43 hours to 7 hours. At most, it is based on 43 hours. And, when the freezer door is opened for 1 second and the time is shortened by 7 minutes, when the operation time reaches 7 hours, the freezer evaporator can be defrosted.

[0123] When the defrost start condition of the freezer evaporator described above is met, the refrigerator evaporator can be defrosted together. In this case, regardless of the defrost start condition of the refrigerator evaporator, the defrost of the refrigerator evaporator can be carried out subordinate to the defrost of the freezer evaporator. In this case, when the heater is operated to defrost the freezer evaporator, the refrigerator evaporator can also be defrosted simultaneously.

[0124] On the other hand, the defrost start condition of the refrigerator evaporator can be based on a specific time. For example, it is based on the time point when the refrigerator operation time is shortened from 20 hours to 7 hours. At most, it is based on 20 hours. And, when the refrigerator door is opened for 1 second and the time is shortened by 7 minutes, when the operation time reaches 7 hours, the refrigerator evaporator can be defrosted.

[0125] Under such conditions, the defrost of the refrigerator evaporator can be carried out independently of the defrost of the freezer evaporator. That is, when the defrost condition of the freezer evaporator is met, the freezer evaporator can be defrosted. When the defrost condition of the refrigerator evaporator is met, the refrigerator evaporator can be defrosted.

[0126] That is, each evaporator can be defrosted in such a way that the defrost of the freezer evaporator and the defrost of the refrigerator evaporator are carried out independently of each other. In this case, even if the heater is operated to defrost the freezer evaporator, when the defrost condition of the refrigerator evaporator is not met, the refrigerator evaporator is not defrosted.

[0127] Figure 7 It is a diagram for explaining the heater control of an embodiment of the present invention.

[0128] Figure 7For explaining the case where, in the second step, the time when the temperature measured by the evaporator temperature sensor 194 reaches the first set temperature exceeds the set time.

[0129] That is, due to an excessive amount of ice formed on the evaporator, even when the heater 170 is operated, the temperature of the evaporator rises slowly and exceeds the set time.

[0130] As Figure 7 shown, the control of the heater 170 can be divided into a first section and a second section.

[0131] When changing from the first section to the second section, the control method of the heater 170 can be changed according to whether the conditions described in the second step are satisfied.

[0132] In Figure 7 the embodiment, even when the heater 170 is operated, since the temperatures of the evaporators 150 and 160 do not rise rapidly within the set time, the heater is controlled in the same manner as in the first section in the second section.

[0133] That is, although the heater 170 is continuously operated in the first section to heat the evaporators 150 and 160, the heater 170 is also continuously operated in the second section to heat the evaporators 150 and 160.

[0134] That is, in Figure 7 the embodiment, it is a diagram for explaining the case where, in the second section, the heater operates in the first mode.

[0135] Similar to the first section, in the second section, the same input value can be supplied to the heater 170 to cause the heater 170 to generate the same amount of heat, thereby heating the evaporators 150 and 160.

[0136] Figures 8 to 15B is for explaining the case where the time for the evaporators 150 and 160 to reach the first set temperature does not exceed the set time and the heater operates in the first mode in the second section.

[0137] Figures 8 to 15B The embodiments of

[0138] Figure 8 are different from each other, and each embodiment is described separately.

[0139] In Figure 8Among them, the control unit 200 determines that within the set time, the heater 170 is repeatedly turned on and off in the second interval.

[0140] After entering the second interval, the time when the heater 170 is first turned off is represented as t 1(off) , and the time when the heater 170 is turned on again is represented as t 1(on) .

[0141] Moreover, the time when the heater 170 is turned off for the second time is represented as t 2(off) , and the time when the heater 170 is turned on again is represented as t 2(on) . After that, although the heater 170 can continue to be turned on or off for the third, fourth time, etc., for the sake of convenience of explanation, the on / off times of the heater 170 are limited to be repeated twice for description.

[0142] In Figure 8 's embodiment, the period T of the sum of the times for the heater 170 to be turned on and off once is fixedly maintained. The period T1 refers to t 1(off) +t 1(on) , and T2 refers to t 2(off) +t 2(on) .

[0143] That is, it is the case where T1 = T2 = t 1(off) +t 1(on) holds.

[0144] In Figure 8 's embodiment, the on-time ratio and off-time ratio of the heater 170 can be fixed at a certain ratio.

[0145] That is, it can be fixedly maintained as t 1(off) :t 1(on) = t 2(off) :t 2(on) = 2:1.

[0146] When entering the second interval, the control unit 200 turns the heater 170 on and off, and can select the on / off method to fixedly maintain their respective time ratios.

[0147] In Figure 8 's embodiment, when entering the second interval, the heater 170 is turned off, that is, there is a time when the heater 170 is turned off, and within the corresponding time, no current is supplied to the heater 170. Therefore, the current supplied to the heater 170 decreases, and the power consumed by the heater 170 decreases, thereby improving energy efficiency.

[0148] During the period when the heater 170 is turned off, the heater 170 has residual heat, and the interior of the chamber where the evaporators 150 and 160 are provided can also be maintained in a heated state. Therefore, during the corresponding time, defrosting can also be performed on the evaporators 150 and 160.

[0149] Therefore, during the period of defrosting the evaporators 150 and 160, the heat supplied by the heater 170 is reduced, thereby preventing the temperature of the storage chamber from rising sharply.

[0150] During the period of turning the heater 170 on and off, when the defrosting end condition is reached, the heater 170 stops operating, and the defrosting of the evaporators 150 and 160 ends.

[0151] Figure 9 It is a diagram for explaining the heater control of another embodiment.

[0152] Figure 9 Unlike Figure 8 it can be kept the same as t 1(off) :t 1(on) =t 2(off) :t 2(on) =1:1. That is, T1 = T2 = t 1(off) +t 1(on) holds.

[0153] That is, after entering the second interval, the time for turning off the heater 170 can be kept the same as the time for turning it on, and the evaporators 150 and 160 are defrosted in the second interval.

[0154] Since the on-time and off-time of the heater 170 are the same at 1:1, there is no need to consider the temperature value measured by the evaporator temperature sensor 194, and only the elapsed time measured by the timer 198 needs to be considered. Therefore, the control unit 200 can simply control the heater 170 by only considering the elapsed time.

[0155] According to Figure 9 When comparing the method with the method of continuously operating the heater without considering the remaining ice (judgment according to the second step) (according to Figure 7 's method), it can be confirmed that the power consumption is approximately reduced by 1.4 - 1.66%. In the experimental results, the overall defrosting time is approximately shortened by 2.5 minutes, and the temperature rise in the storage chamber becomes slower. When continuously operating the heater without considering the second step, the temperature in the storage chamber rises by about 4.3 degrees. However, according to Figure 9 's method, the temperature in the storage chamber rises by about 3.8 degrees, so it is also confirmed that there is an effect that the temperature rise in the storage chamber becomes slower.

[0156] That is, through Figure 9 the embodiment of Figure 9 , the amount of residual ice during defrosting is sensed, so that when changing the operation mode of the heater, it can be confirmed that the defrosting time is shortened and the temperature rise of the storage compartment becomes slower. Therefore, the energy consumed during defrosting of the refrigerator can be saved, and it is confirmed that there is an effect of preventing food spoilage due to the temperature rise of the storage compartment.

[0157] Figure 10 FIG. is a diagram for explaining the heater control of another embodiment.

[0158] In Figure 10 , T1 = T2, on the other hand, t 1(off) :t 1(on) = 1:1 and t 2(off) :t 2(on) = 2:1 to make the ratio of the opening time to the closing time different.

[0159] That is, as time passes, the time when the heater 170 is turned off increases, so that in the later stage of defrosting compared with the earlier stage, it is adjusted to reduce the average heat supplied from the heater 170 per hour.

[0160] Therefore, the peripheral temperature of the evaporators 150 and 160 rises sufficiently. When time passes and heat exchange with the surrounding air is required, additional heat is no longer supplied through the heater 170, thereby improving energy efficiency. Similarly, when the peripheral temperature of the evaporators 150 and 160 rises, the rate of the peripheral temperature rise can be reduced, thereby reducing the situation where the food stored in the storage compartment is exposed to high temperatures.

[0161] Figure 11 FIG. is a diagram for explaining the heater control of another embodiment.

[0162] In Figure 11 , it is changed with a period of T1 > T2. On the other hand, it is a method of controlling the heater 170 in a fixed manner where t 1(off) :t 1(on) = t 2(off) :t 2(on) = 1:1.

[0163] In Figure 11 , it may refer to a method in which the time interval for the heater 170 to switch on / off becomes smaller as the later stage of defrosting progresses. That is, the more defrosting is performed, the faster the heater 170 is switched on / off, and thus, the less heat supplied through the heater 170 can be reduced in the later stage.

[0164] Therefore, the temperature of the heater 170 is adjusted so that it does not increase, and by reducing the heat supplied to the evaporators 150 and 160, it is possible to prevent the temperature around the evaporators 150 and 160 from rising sharply.

[0165] Figure 12 It is a diagram for explaining the heater control of another embodiment.

[0166] In Figure 12 it changes in a cycle of T1 > T2, and in a variable manner where t 1(off) :t 1(on) = 1:1, t 2(off) :t 2(on) = 2:1 to control the heater 170.

[0167] Figure 12 Similar to Figure 11 it is a method of reducing the cycle and changing the switching time.

[0168] In Figure 12 the embodiment of, also during defrosting, as time passes, it changes to a method where the time the heater 170 is turned on is shortened. Therefore, in the later stage of defrosting, the power consumed by the heater 170 decreases, and thus energy efficiency can be improved.

[0169] Figure 13 It is a diagram for explaining the heater control of another embodiment.

[0170] In Figure 13 when it is determined that it is within the set time, compared to the first interval, the input value provided to the heater 170 in the second interval can be made smaller.

[0171] In the second interval, the input value of the heater 170 continuously decreases, so that the heat supplied through the heater 170 during the second interval can be reduced.

[0172] The second interval is a state where a certain amount or more of heat is provided to the evaporators 160 and 170. Therefore, even without supplying additional heat, the ice frozen on the evaporators 160 and 170 can be melted by the heat remaining in the heater 170 and the heat inside the chamber where the evaporators 160 and 170 are provided.

[0173] Therefore, the heat supplied through the heater 170 is gradually reduced in the second interval, so that it is possible to prevent hot air from flowing into the storage chamber and causing the temperature of the storage chamber to rise sharply.

[0174] At this time, an input value based on a linear function is supplied to the heater 170, whereby the heat emitted from the heater 170 also decreases in a form based on a linear function. That is, the input value of the heater 170 can be decreased in proportion to the elapsed time.

[0175] In Figure 13 , the vertical axis can be the electric power or current supplied to the heater 170, but it can also be the heat emitted from the heater 170.

[0176] In the second interval, there is a region where an input value smaller than the input value supplied to the heater 170 in the first interval is provided. Therefore, the heat generated per hour by the heater 170 in the second interval is less than the heat generated per hour in the first interval.

[0177] The defrost end condition, that is, when the temperature measured by the evaporator temperature sensor 194 reaches the second set temperature, the defrosting of the evaporators 150 and 160 ends. At this time, no current is supplied to the heater 170, and no additional heat is generated by the heater 170, so that the defrosting can end.

[0178] The inclination angle for decreasing the input value of the heater 170 can be changed into various forms. For example, as time passes, the input value can decrease rapidly or slowly. As Figure 13 shown, in the case of slow decrease, before the input value of the heater 170 reaches 0, the heater 170 can be controlled in a way that ends the defrosting.

[0179] Figure 14 is a diagram for explaining the heater control of another embodiment.

[0180] According to Figure 14 the embodiment, when it is determined that it is within the set time, compared with the first interval, the input value provided to the heater 170 in the second interval can be decreased.

[0181] When the input value input in the first interval is P1, input values P2, P3, etc. smaller than P1 are input to the heater 170 in the second interval, so that a smaller input value can be provided to the heater 170 in the second interval.

[0182] The input values P2, P3, etc. input in the second interval are not continuous, but are applied to the heater 170 in a discontinuous and stepwise decreasing manner.

[0183] That is, in the second interval, as time passes, smaller input values are supplied to the heater 170 step by step.

[0184] The reduction ratios of input values such as P2, P3, P4, etc. may be the same or different. When the reduction ratio of the input value changes, as time passes, it can be deformed in a manner of decreasing at a reduction ratio in the second interval. On the contrary, it is also possible to control the input values of P2, P3, P4, etc. to decrease by the same value.

[0185] As time passes, a small input value is applied to the heater 170 in the second interval, so that as time passes, the heat provided by the heater 170 is reduced. In a state where the temperatures of the evaporators 160 and 170 are rising, by reducing the temperature rise amplitude of the evaporators 160 and 170, it is possible to prevent a sharp rise in the temperature inside the storage chamber.

[0186] The same input value P1 is continuously provided in the first interval, so that at the initial stage of defrosting the evaporators 150 and 160, a large amount of heat can be provided to the evaporators 150 and 160 in a short time. And, a relatively small amount of heat is provided for a long time in the second interval, and the evaporators 150 and 160 exchange heat with the surrounding air of the chamber, so that sufficient time can be provided for melting the frosted ice.

[0187] Of course, in the second step, when the temperature of the evaporator measured by the evaporator temperature sensor 194 does not reach the first set temperature within the set time, the input value of P1 the same as that in the first interval can also be provided to the heater 170 in the second interval. Even if defrosting is performed through the first interval, it can be determined that a large amount of residual ice remains in the evaporators 160 and 170, so the heat provided from the heater 170 to the evaporators 160 and 170 is not reduced.

[0188] In Figure 14 the embodiment, when the temperature measured by the evaporator temperature sensor 194 reaches the second set temperature of the defrosting end condition, the supply of current to the heater 170 can also be interrupted.

[0189] Figure 15A 、 Figure 15B is a diagram for explaining the heater control of another embodiment.

[0190] A plurality of heaters 172 and 174 can be provided for the heater 170, and each heater can be independently controlled.

[0191] As Figure 15A shown, the sheathed heater can apply input values to the heater in three stages according to the passage of time. On the other hand, as Figure 15B shown, the wire heater can apply input values to the heater in two stages.

[0192] When combined according toFigure 15A Control and according to Figure 15B For the control, when using multiple heaters, the input value can be gradually reduced for control.

[0193] That is, in the first interval, multiple heaters, namely, the sheathed heater and the wire heater, are all operated. On the other hand, in the second interval, either the sheathed heater or the wire heater can be operated alone.

[0194] In contrast, in the first interval, multiple heaters, namely, the sheathed heater and the wire heater, are all operated. On the other hand, in the second interval, the input values of the sheathed heater and the wire heater can be gradually reduced and operated respectively.

[0195] Overall, the total heat supplied by multiple heaters in the second interval is reduced, and the heat supplied to the evaporators 150 and 160 is reduced, thereby reducing the temperature rise rate of the evaporators.

[0196] Figure 16 It is a diagram for explaining another embodiment of heater control.

[0197] Figure 16 It is based on Figures 8 to 12 Combined with the content from Figures 13 to 15B The content.

[0198] That is, when supplying heat to the evaporators 150 and 160 through the heater for defrosting, when the temperature of the evaporators 150 and 160 rises to the first set temperature within the set time, while turning on / off the heater 170 in the second interval, the input value provided to the heater 170 during the time when the heater 170 is turned on can be reduced.

[0199] Since Figure 16 The content of the embodiment is repeated with the above content, so the detailed description is omitted.

[0200] The present invention is not limited to the above embodiments, and as the protection scope of the present invention, those of ordinary skill in the technical field to which the present invention pertains can make modifications, and such modifications belong to the scope of the present invention.

Claims

1. A control method for a refrigerator, characterized in that: It includes: The first step is to heat the evaporator by continuously operating a heater, the heater supplies heat to the evaporator, and the evaporator supplies cold air to the storage compartment; The second step is to determine whether the time for the evaporator to reach the set temperature is within the set time; and The third step is that in the second step, when it is determined that it is not within the set time, the heater is continuously operated in the same manner as in the first step, and in the second step, when it is determined that it is within the set time, the heater is operated differently from the first step.

2. The control method for a refrigerator according to claim 1, characterized in that: In the third step, When it is determined that it is within the set time, the heater is repeatedly turned on / off.

3. The control method for a refrigerator according to claim 2, characterized in that: In the third step, The ratio of the on-time to the off-time of the heater is fixed.

4. The control method for a refrigerator according to claim 3, characterized in that: In the third step, The ratio of the on-time to the off-time of the heater is 1:

1.

5. The control method for a refrigerator according to claim 2, characterized in that: In the third step, The ratio of the on-time to the off-time of the heater is variable.

6. The control method for a refrigerator according to claim 5, characterized in that: In the third step, The off-time of the heater is longer than the on-time.

7. The control method for a refrigerator according to claim 2, characterized in that: In the third step, The cycle of turning the heater on / off is fixed.

8. The control method for a refrigerator according to claim 2, characterized in that: In the third step, The cycle of turning the heater on / off is variable.

9. The control method for a refrigerator according to claim 1, characterized in that: In the third step, When it is determined that it is within the set time, current is repeatedly supplied to / withheld from the heater.

10. A refrigerator, characterized in that: It includes: An evaporator that provides cold air to the storage compartment; An evaporator temperature sensor that measures the temperature of the evaporator; A timer that measures the elapsed time; A heater that supplies heat to the evaporator; and A control unit that controls the heater, After starting to operate the heater, the control unit determines whether the time for the evaporator to reach the set temperature is within the set time. When it is not within the set time, the heater is operated in the same manner as before. When it is within the set time, the heater is operated differently from before.

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