Refrigerator

Abstract

To solve the problems that in a conventional refrigerator, it is difficult to control a power consumption of a refrigerator depending on the operating state of a heating unit, and there is a risk that bacteria in water in a water supply pipe may grow.SOLUTION: An ice maker 30 of a refrigerator 10 mainly comprises a water supply tank 31, an ice tray 32, an ice storage container 33, a water supply pump 34, a water supply pipe 35, and a heating unit 36. Then, a control unit 40 determines the presence or absence of water in the water supply tank 31 via an infrared sensor 44, and variably controls an energization rate to the heating unit 36 according to the determination content. With this structure, bacteria are prevented from growing in the water remaining in the water supply pipe, and a power consumption of the refrigerator 10 is suppressed.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a refrigerator equipped with an ice-making device, and more particularly to a refrigerator that prevents water remaining in a water supply pipe of the ice-making device from freezing and clogging the water supply pipe, and reduces power consumption by variably controlling the power supply rate of a heating section of the ice-making device. [Background technology]

[0002] Patent Document 1 discloses a conventional refrigerator. The refrigerator includes an ice-making device, which includes a water supply tank disposed in a refrigerator compartment, an ice tray and an ice storage case disposed in the ice-making compartment, and a water supply pump and a water supply pipe that supply water from the water supply tank to the ice tray.

[0003] In the ice making device, a driving current is applied to the water supply pump, and water is sucked up from the water supply tank and supplied to the ice tray through the water supply pipe. A pipe heater, which is a heating means, is provided at the portion of the water supply pipe that is disposed inside the ice making chamber, to prevent water remaining in the water supply pipe from freezing inside the water supply pipe. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 4740072 Summary of the Invention [Problem to be solved by the invention]

[0005] As described above, in conventional refrigerators, the microcomputer detects the presence or absence of water in the water tank, and operates the pipe heater when it detects that there is water in the water tank, and stops the pipe heater when it detects that the water tank is empty. In this way, the pipe heater is operated appropriately to reduce the amount of power consumed by the refrigerator.

[0006] However, in a conventional refrigerator, when there is water in the water tank, the pipe heater is in an operating state. And, it is sufficient that the water supply pipe is in an open state at least immediately before the water supply operation to the ice tray is started, and there is a problem that it is difficult to reduce the power consumption by operating the pipe heater more than necessary.

[0007] In addition, if the pipe heater is operated more than necessary, the water supply pipe will become hot, causing the temperature of the water remaining in the water supply pipe to rise, which may lead to the growth of bacteria.

[0008] The present invention has been made in consideration of the above-mentioned circumstances, and has an object to provide a refrigerator that prevents water remaining in the water supply pipe of the ice-making device from freezing and clogging the water supply pipe, and reduces power consumption by variably controlling the power supply rate of the heating section of the ice-making device. [Means for solving the problem]

[0009] The refrigerator of the present invention comprises a water supply tank for storing water, an ice tray for making ice from the water, an ice maker for de-icing the ice made in the ice tray, a water supply pump for sucking in the water from the water supply tank, a water supply pipe for sending the water sucked in by the water supply pump to the ice tray, a heating unit for heating the water supply pipe, and a control unit for determining the presence or absence of water in the water supply tank and for variably controlling a power supply rate to the heating unit, wherein the control unit sets the power supply rate to the heating unit higher before operation of the water supply pump than the power supply rate to the heating unit after operation of the water supply pump.

[0010] In addition, in the refrigerator of the present invention, the control unit determines for the first time that the water supply tank is empty, and after a certain time has elapsed since the power supply rate to the heating unit was maximized, reduces the power supply rate to the heating unit and determines for the second time whether water is present in the water supply tank.

[0011] In addition, in the refrigerator of the present invention, the control unit stops the supply of electricity to the heating unit after determining twice consecutively that the water tank is empty and further determining that an insulated door that can be opened and closed to cover the interior in which the water tank is located has not been opened.

[0012] In addition, in the refrigerator of the present invention, after the control unit determines that the water supply tank is empty twice in succession and further determines that an insulated door that freely opens and closes the interior in which the water supply tank is arranged has opened and closed, after the certain time has elapsed since the power supply rate to the heating unit was maximized, the control unit reduces the power supply rate to the heating unit and then drives the water supply pump.

[0013] In addition, the refrigerator of the present invention is characterized in that it includes a compressor that constitutes a refrigeration cycle, and the control unit increases the power supply rate to the heating unit when the compressor is operating compared to when the compressor is stopped.

[0014] In addition, in the refrigerator of the present invention, when driving the water supply pump, the control unit first operates the motor driving the water supply pump in a reverse direction, then operates it in a forward direction, and finally operates it in the reverse direction again. Effect of the Invention

[0015] In the refrigerator of the present invention, the control unit sets the power supply rate to the heating unit before the water supply pump is operated higher than the power supply rate to the heating unit after the water supply pump is operated, and sets the power supply rate to the heating unit at a low level that does not cause water in the water supply pipe to freeze for a certain period of time after the water supply pump is operated. This control method makes it possible to prevent water remaining in the water supply pipe from freezing and clogging the water supply pipe, and to reduce the amount of power consumed by the refrigerator.

[0016] In addition, in the refrigerator of the present invention, the control unit determines that the water tank is empty at the first time, and maximizes the power supply rate to the heating unit to heat the water supply pipe. With this control method, even if the water in the water supply pipe is frozen and blocked due to variations in the assembly of refrigerator parts, the frozen water can be melted and water can be supplied to the ice tray.

[0017] In addition, in the refrigerator of the present invention, the control unit determines that the water tank is empty for the first time, maximizes the power supply rate to the heating unit, and then determines that the water tank is empty twice in succession and stops power supply to the heating unit under certain control conditions. With this control method, the control unit determines that the water supply pipe is not blocked and the water tank is empty, thereby making it possible to reduce the amount of power consumed by the refrigerator.

[0018] In addition, in the refrigerator of the present invention, after it is determined twice in succession that the water supply tank is empty and further after it is determined that the insulated door that freely closes the interior in which the water supply tank is arranged has opened and closed, the power supply rate to the heating unit is reduced after a certain time has elapsed since the power supply rate to the heating unit was maximized, and then the water supply pump is driven, thereby preventing blockage due to freezing in the water supply pipe and preventing the water remaining in the water supply pipe from reaching a high temperature, thereby preventing the growth of bacteria in the water.

[0019] In addition, in the refrigerator of the present invention, the amount of heat applied to the water supply pipe is reduced when the compressor is stopped compared to when the compressor is operating, thereby preventing the water remaining in the water supply pipe from reaching a high temperature, thereby preventing the growth of bacteria in the water.

[0020] In addition, in the refrigerator of the present invention, when the control unit operates the water supply pump, the control unit operates the drive motor in the following order: reverse rotation, forward rotation, reverse rotation. With this control method, even if water that has been melted by heating by the heating unit remains near the tip of the water supply pipe due to surface tension, the control unit first operates the drive motor in the reverse direction to suck up the water near the tip of the water supply pipe, thereby preventing the water from splashing into the ice tray due to bumping. [Brief description of the drawings]

[0021] [Figure 1] 1A and 1B are diagrams illustrating a refrigerator according to an embodiment of the present invention, in which (A) is a perspective view of the refrigerator from the front, and (B) is a side cross-sectional view of the refrigerator. [Diagram 2] FIG. 1 is a diagram illustrating a refrigerator according to an embodiment of the present invention, where (A) is a side cross-sectional view illustrating an ice-making device, and (B) is a block diagram showing an overview of the ice-making device. [Diagram 3] 1 is a table illustrating an ice making operation of the refrigerator according to the embodiment of the present invention. [Figure 4] 4 is a flowchart illustrating an ice making operation of the refrigerator according to the embodiment of the present invention. [Diagram 5] 4 is a flowchart illustrating an ice making operation of the refrigerator according to the embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] The refrigerator 10 of this embodiment will be described in detail below with reference to the drawings. In the following description, the up-down direction indicates the height direction of the refrigerator 10, the left-right direction indicates the width direction of the refrigerator 10 as viewed from the front, and the front-rear direction indicates the depth direction of the refrigerator 10. In addition, when describing this embodiment, the same reference numbers are used for the same members as a general rule, and repeated description will be omitted.

[0023] Fig. 1(A) is a perspective view of refrigerator 10 of this embodiment as seen from the front. Fig. 1(B) is a side cross-sectional view of refrigerator 10 of this embodiment. Fig. 2(A) is a side cross-sectional view explaining ice-making device 30 provided in refrigerator 10 of this embodiment. Fig. 2(B) is a block diagram explaining ice-making device 30 of refrigerator 10 of this embodiment. In Fig. 1(B), the flow of cool air is indicated by arrows.

[0024] As shown in Fig. 1(A), the inside of the insulated box 11 of the refrigerator 10 is used as a storage compartment, and the storage compartment is divided into a refrigerator compartment 12 (see Fig. 1(B)) and a freezer compartment 13 (see Fig. 1(B)) by an insulated partition wall 27 (see Fig. 1(B)). The front opening of the refrigerator compartment 12 is closed by an insulated door 18 so as to be freely opened and closed, and the front opening of the freezer compartment 13 is closed by an insulated door 19 so as to be freely opened and closed. The insulated doors 18, 19 are rotating doors whose right end is rotatably supported by the insulated box 11. Note that the insulated doors 18, 19 may be drawer doors or double doors.

[0025] As shown in Fig. 1(B), a cooling chamber 21 is defined behind the freezing chamber 13, and an evaporator 20 is disposed in the cooling chamber 21. A machine chamber 14 is defined behind the bottommost part of the insulated box 11, and a compressor 23 and the like are disposed in the machine chamber 14. The evaporator 20 and the compressor 23 are connected to an expansion means and a condenser (not shown) via refrigerant piping to form a vapor compression refrigeration cycle. A defrosting heater 26 for melting frost on the evaporator 20 is disposed below the evaporator 20.

[0026] A blower 25 is disposed above the cooling chamber 21, and the cool air inside the cooling chamber 21 cooled by the evaporator 20 is blown to the refrigerator chamber 12 and the freezer chamber 13 via the blower 25. A damper 24 is disposed in the air path to the refrigerator chamber 12.

[0027] Here, the control unit 40 (see FIG. 2(B)) detects the temperature inside the refrigerator compartment 12 using an internal temperature sensor 42 (see FIG. 2(B)) and controls the opening and closing of the damper 24. Then, the flow rate of cold air to the refrigerator compartment 12 is adjusted to keep the temperature inside the refrigerator compartment 12 constant. Then, by the above control by the control unit 40, the refrigerator compartment 12 is cooled to the refrigeration temperature band. By similar control, the freezer compartment 13 is cooled to the freezing temperature band. The cold air that has cooled the refrigerator compartment 12 and the freezer compartment 13 returns to the cooling compartment 21 via the return air duct.

[0028] As shown in the figure, the insulating box 11 mainly includes an outer box 15 made of a steel plate forming the outer shape of the refrigerator 10, an inner box 16 made of a box-shaped synthetic resin plate formed inside the outer box 15, and an insulating material 17 disposed between the outer box 15 and the inner box 16. As the insulating material 17, for example, urethane foam is used.

[0029] 2(A) shows the state in which ice-making device 30 of refrigerator 10 is disposed in refrigeration compartment 12 and freezer compartment 13. In freezer compartment 13, ice storage container 33 and storage containers 38, 39 are disposed, and the freezer compartment is divided into three levels in the height direction. Frozen foods, for example, are stored in storage containers 38, 39, and can be removed by sliding storage containers 38, 39 toward the depth direction of freezer compartment 13.

[0030] As shown in the figure, ice making device 30 mainly includes water supply tank 31, ice tray 32, ice storage container 33, water supply pump 34, water supply pipe 35, heating unit 36, and ice maker 37. Water supply tank 31 stores water to be supplied to ice tray 32, and is disposed on the upper surface of heat-insulating partition wall 27 of refrigerator compartment 12. A user opens heat-insulating door 18, takes out water supply tank 31 as needed, and supplies water into water supply tank 31.

[0031] In addition, a water supply pump 34 is also disposed in the refrigerator compartment 12 near the water supply tank 31, and a motor 45 for the water supply pump (see FIG. 2(B)) is controlled by the control unit 40. During normal ice-making operation, for example, one cycle is at intervals of 120 minutes, and the water in the water supply tank 31 is sucked up and supplied to the ice tray 32.

[0032] Ice maker 37 is disposed above ice storage container 33 in freezer compartment 13, and has a rotating twisting unit (not shown) that automatically drops ice made in ice making tray 32 into ice storage container 33, and an ice storage amount detection unit (not shown) that detects the amount of ice stored in ice storage container 33. As shown in the figure, ice making tray 32 is inside ice maker 37, for example, below insulating partition wall 27, and disposed above ice storage container 33.

[0033] The water supply pipe 35 is connected to the water supply pump 34, and is arranged to extend from the refrigerator compartment 12 to the freezer compartment 13 through the inside of the heat-insulating partition wall 27. A pipe heater serving as a heating unit 36 ​​is arranged on the outer circumferential surface of the water supply pipe 35 to prevent the water remaining in the water supply pipe 35 from freezing. Note that, as will be described in detail later, the power supply rate to the heating unit 36 ​​is appropriately variably controlled by the control unit 40, thereby suppressing the amount of power consumed by the refrigerator 10.

[0034] Control unit 40 constitutes an electronic control unit (ECU) that executes various calculations for controlling refrigerator 10, and controls the ice-making operation of ice-making device 30. Connected to control unit 40 are timer 41, internal temperature sensor 42, door open / close sensor 43, infrared sensor 44, compressor 23, motor 45 for water supply pump 34 (hereinafter referred to as "motor 45"), heating unit 36, ice maker 37, etc.

[0035] Timer 41 measures the operating time and stop time of various devices constituting refrigerator 10, such as compressor 23 and ice-making device 30. In addition, internal temperature sensor 42 measures the internal temperatures of refrigerator compartment 12 and freezer compartment 13. In addition, door opening / closing sensor 43 detects the open / closed states of insulated doors 18, 19 of refrigerator compartment 12 and freezer compartment 13. In addition, infrared sensor 44 detects the bottom temperature of ice tray 32.

[0036] In addition, the control unit 40 executes a predetermined calculation process based on input information from a timer 41, an internal temperature sensor 42, a door opening / closing sensor 43 and an infrared sensor 44, and controls the operation and stopping of the compressor 23, the water supply pump 34, the heating unit 36 ​​and the ice maker 37 based on the calculation process.

[0037] Fig. 3 is a table for explaining the situation in which the power supply rate to heating unit 36 ​​is variably controlled during ice-making operation of ice-making device 30 of refrigerator 10 of this embodiment. Fig. 4 is a flowchart for explaining the ice-making operation of ice-making device 30 of refrigerator 10 of this embodiment, and corresponds to power supply rate A and power supply rate D of Fig. 3. Fig. 5 is a flowchart for explaining the ice-making operation of ice-making device 30 of refrigerator 10 of this embodiment, and corresponds to power supply rate B and power supply rate C of Fig. 3. In addition, in explaining Figs. 3 to 5, Figs. 1 and 2 and their explanations will be referred to as appropriate.

[0038] As shown in Fig. 3, condition 1 in ice-making operation is "an operating state in which the cooling strength of freezer compartment 13 is 7 or more out of 10 or the mode is quick ice-making mode or quick freezing mode, and the temperature of freezer compartment 13 is lower than -18°C". Condition 2 in ice-making operation is "an operating state after water supply tank 31 is detected as empty for the first time". Condition 3 in ice-making operation is "an operating state other than the above conditions 1 and 2". In ice-making device 30 of refrigerator 10, the power supply rate to heating unit 36 ​​is variably controlled depending on whether compressor 23 is operating or stopped in the operating states of refrigerator 10 of conditions 1 to 3 above.

[0039] The quick ice making mode is a mode in which ice is made in one cycle that is shorter than the normal ice making operation, and the quick freezing mode is a mode in which the freezing compartment 13 is cooled quickly with priority over the refrigerating compartment 12.

[0040] As illustrated, in the present embodiment, the operating conditions of refrigerator 10 under the above conditions 1 to 3 have four patterns of power supply rate A to power supply rate D. In each of the patterns of power supply rate A to power supply rate D, the power supply rate to heating unit 36 ​​is higher when compressor 23 is operating than when compressor 23 is stopped.

[0041] When the compressor 23 is operating, the blower 25 is operated and the cold air inside the cooling chamber 21 circulates inside the chamber, thereby cooling the water supply pipe 35. Therefore, by increasing the amount of heat generated by the heating unit 36 ​​and heating the water supply pipe 35, the water in the water supply pipe 35 is prevented from freezing.

[0042] On the other hand, when compressor 23 is stopped, blower 25 is also stopped, and water supply pipe 35 is difficult to cool to at least a temperature lower than the inside temperature. Therefore, the amount of heat generated from heating unit 36 ​​is reduced, and water supply pipe 35 is prevented from reaching an unnecessarily high temperature state. With this control method, when compressor 23 is stopped, the temperature of the water remaining in water supply pipe 35 rises, preventing the growth of bacteria and suppressing the power consumption of refrigerator 10.

[0043] Here, in normal ice-making operation of ice maker 30, water supply pump 34 is operated at intervals of 120 minutes, one cycle of which sucks up water from water supply tank 31 and supplies the water to ice tray 32. In normal ice-making operation, 70 minutes from the previous water supply from water supply tank 31 is set as a reference, and the power supply rate to heating unit 36 ​​from the time the 70 minutes have elapsed until the start of the next water supply from water supply tank 31 is controlled to be higher than the power supply rate to heating unit 36 ​​from the previous water supply from water supply tank 31 until the 70 minutes. Note that the 70 minutes is one example of this embodiment, and any design change is possible depending on the model of refrigerator 10, the program of ice-making operation, etc.

[0044] In addition, in the four patterns of power rate A to power rate D, the most appropriate power rate is selected from the four levels of power rate depending on the water filling level in the water supply tank 31 and the elapsed time during ice-making operation.

[0045] In the first stage, the power supply rate when the compressor 23 is operating is 15%, and the power supply rate when the compressor 23 is stopped is 10%. In the second stage, the power supply rate when the compressor 23 is operating is 30%, and the power supply rate when the compressor 23 is stopped is 25%. In the third stage, the power supply rate when the compressor 23 is operating is 50%, and the power supply rate when the compressor 23 is stopped is 40%. In the fourth stage, the power supply rate is 100% both when the compressor 23 is operating and when it is stopped.

[0046] First, a control method for power conduction rate A of refrigerator 10 will be described with reference to Fig. 4. As shown in the figure, the control method for power conduction rate A is performed when control unit 40 detects that water supply tank 31 is empty twice consecutively by infrared sensor 44 after the previous water supply operation. Steps S10 to S16 in Fig. 4 correspond to the control method for power conduction rate A.

[0047] In step S10, if the control unit 40 determines based on the detection signal from the infrared sensor 44 that water has not been supplied to the ice tray 32 twice in a row at NO in step S61 (see Figure 5), the control unit 40 determines that there is no water in the water supply tank 31, that is, that the water tank 31 is in an empty state.

[0048] In step S11, the control unit 40 judges whether or not the insulation door 18 of the refrigerator compartment 12 has been opened based on the detection signal from the door open / close sensor 43. Then, when the control unit 40 receives the detection signal and judges that the insulation door 18 of the refrigerator compartment 12 has been opened (YES in step S11), the process proceeds to step S17, and the control unit 40 starts controlling the power distribution rate D.

[0049] On the other hand, if the control unit 40 determines at NO in step S11 that the insulated door 18 of the refrigerator compartment 12 is not open without receiving the detection signal, the control unit 40 determines at step S12 whether the operating status of the refrigerator 10 satisfies the above-mentioned condition 1 or not.

[0050] If the control unit 40 determines that the operation status of the refrigerator 10 satisfies the above-mentioned condition 1 at YES in step S12, the process proceeds to step S13, where it is determined whether the compressor 23 is operating. If the control unit 40 determines that the operation status of the refrigerator 10 does not satisfy the above-mentioned condition 1 at NO in step S12, the process proceeds to step S16, where the control unit 40 stops the supply of electricity to the heating unit 36, and the process returns to step S11.

[0051] If the control unit 40 determines that the compressor 23 is operating at YES in step S13, then in step S14, the control unit 40 reduces the power supply rate to the heating unit 36 ​​to 30% and continues the power supply, and returns to step S11.

[0052] On the other hand, if the control unit 40 determines that the compressor 23 is stopped at NO in step S13, in step S15, the control unit 40 reduces the power supply rate to the heating unit 36 ​​to 25% and continues the power supply, and returns to step S11.

[0053] Next, a control method for power conduction rate D of refrigerator 10 will be described with reference to Fig. 4. As shown in the figure, the control method for power conduction rate D is used when there is a possibility that the user has supplied water to water supply tank 31 after control unit 40 detects an empty state of water supply tank 31 after the previous water supply operation to ice tray 32. Steps S17 to S21 in Fig. 4 correspond to the control method for power conduction rate D.

[0054] In step S17, it is determined whether or not the insulated door 18 of the refrigerator compartment 12 has been closed, based on a detection signal from the door open / close sensor 43. Then, if the control unit 40 determines that the insulated door 18 of the refrigerator compartment 12 has been closed (YES in step S17), in step S18, the control unit 40 increases the power supply rate to the heating unit 36 ​​to 100% and continues the power supply.

[0055] Furthermore, if the control unit 40 determines that the insulated door 18 of the refrigerator compartment 12 is not closed at NO in step S17, the control unit 40 continues to determine the closing operation of the insulated door 18 of the refrigerator compartment 12 based on the detection signal from the door opening / closing sensor 43.

[0056] In step S19, it is determined whether or not 15 minutes have passed since the insulated door 18 of the refrigerator compartment 12 was closed, based on a detection signal from the timer 41. Then, if the control unit 40 determines that 15 minutes have passed since the insulated door 18 of the refrigerator compartment 12 was closed (YES in step S19), in step S20, the control unit 40 reduces the power supply rate to the heating unit 36 ​​to 50% and continues power supply.

[0057] Furthermore, if the control unit 40 determines at NO in step S19 that 15 minutes have not elapsed since the insulated door 18 of the refrigerator compartment 12 was closed, the control unit 40 continues to determine whether the 15 minutes have elapsed based on the detection signal from the timer 41.

[0058] In step S21, the control unit 40 determines whether or not 45 minutes have passed since the insulation door 18 of the refrigerator compartment 12 was closed, based on the detection signal from the timer 41. Then, if the control unit 40 determines that 45 minutes have passed since the insulation door 18 of the refrigerator compartment 12 was closed (YES in step S21), the process proceeds to step S30, where the control unit 40 starts controlling the power distribution rate B.

[0059] Furthermore, if the control unit 40 determines at NO in step S21 that 45 minutes have not elapsed since the insulated door 18 of the refrigerator compartment 12 was closed, the control unit 40 continues to determine whether the 45 minutes have elapsed based on the detection signal from the timer 41.

[0060] Next, a control method for power conduction rate B of refrigerator 10 will be described with reference to Fig. 5. As shown in the figure, the control method for power conduction rate B is used when water supply tank 31 is not empty and the operation status of refrigerator 10 satisfies condition 1 or condition 3. Steps S30 to S49 in Fig. 5 correspond to the control method for power conduction rate B.

[0061] In step S30, control unit 40 determines whether ice storage container 33 is full of ice via an ice storage amount detection unit (not shown) of ice maker 37. If control unit 40 determines that ice storage container 33 is not full of ice (NO in step S30), control unit 40 performs the operation of removing ice from ice tray 32 and then supplies water to ice tray 32 in step S31.

[0062] In step S32, control unit 40 determines whether or not the first water supply operation to ice tray 32 has been performed based on the detection signal from infrared sensor 44. If control unit 40 determines that the first water supply operation to ice tray 32 has not been performed (NO in step S32), the process proceeds to step S50, where control unit 40 starts controlling current supply rate C.

[0063] On the other hand, if the control unit 40 determines that the first water supply operation to ice tray 32 has been performed at YES in step S32, then at step S33, control unit 40 starts the ice making operation in ice tray 32, and at step S34, control unit 40 determines whether or not the operating status of refrigerator 10 satisfies the above-mentioned condition 1.

[0064] If the control unit 40 determines that the operating status of the refrigerator 10 satisfies the above-mentioned condition 1 at YES in step S34, the process proceeds to step S35, where it determines whether the compressor 23 is operating. If the control unit 40 determines that the compressor 23 is operating at YES in step S35, the control unit 40 maintains the power supply rate to the heating unit 36 ​​at 50% and continues power supply at step S36.

[0065] On the other hand, if the control unit 40 determines that the compressor 23 is stopped (NO in step S35), then in step S37, the control unit 40 reduces the power supply rate to the heating unit 36 ​​to 40% and continues the power supply.

[0066] If the control unit 40 determines that the operating status of the refrigerator 10 does not satisfy the above-mentioned condition 1 at NO in step S34, the process proceeds to step S38, where it determines whether the compressor 23 is operating. If the control unit 40 determines that the compressor 23 is operating at YES in step S38, the control unit 40 reduces the power supply rate to the heating unit 36 ​​to 15% and continues power supply at step S39.

[0067] On the other hand, if the control unit 40 determines that the compressor 23 is stopped at NO in step S38, then in step S40, the control unit 40 reduces the power supply rate to the heating unit 36 ​​to 10% and continues the power supply.

[0068] In step S41, control unit 40 determines whether or not 70 minutes have passed since the start of the previous water supply to ice tray 32 in step S32, based on the detection signal from timer 41. Then, if control unit 40 determines that 70 minutes have passed since the start of water supply in step S32 (YES in step S41), the process proceeds to step S42, where control unit 40 determines whether compressor 23 is operating or not.

[0069] If the control unit 40 determines that the compressor 23 is operating at YES in step S42, then in step S43 the control unit 40 increases the power supply rate to the heating unit 36 ​​to 50% and continues the power supply. On the other hand, if the control unit 40 determines that the compressor 23 is stopped at NO in step S42, then in step S44 the control unit 40 increases the power supply rate to the heating unit 36 ​​to 40% and continues the power supply.

[0070] In step S45, the control unit 40 judges whether or not the set time has elapsed since the start of ice making in step S33 based on the detection signal from the timer 41. If the control unit 40 judges that the set time has elapsed since the start of ice making in step S33 (YES in step S45), the process returns to step S30. However, if the control unit 40 judges that the set time has not elapsed since the start of ice making in step S45 (NO), the process returns to step S42.

[0071] If control unit 40 determines that ice storage container 33 is full of ice at YES in step S30, the process proceeds to step S46, where it determines whether compressor 23 is operating. If control unit 40 determines that compressor 23 is operating at YES in step S46, control unit 40 increases the power supply rate to heating unit 36 ​​to 50% and continues power supply at step S47.

[0072] On the other hand, if the control unit 40 determines that the compressor 23 is stopped (NO in step S46), then in step S49, the control unit 40 increases the power supply rate to the heating unit 36 ​​to 40% and continues the power supply.

[0073] Thereafter, in step S48, control unit 40 determines whether a predetermined set time, for example, one hour, has passed since ice storage container 33 was detected as full of ice in step S30 based on the detection signal from timer 41. If control unit 40 determines that the predetermined set time has passed since ice storage container 33 was detected as full of ice in step S30 (YES in step S48), control unit 40 returns to step S30. However, if control unit 40 determines that the predetermined set time has not passed since ice storage container 33 was detected as full of ice (NO in step S48), control unit 40 returns to step S46.

[0074] Incidentally, if the control unit 40 determines that 70 minutes have not elapsed since the start of water supply (NO in step S41), the process returns to step S33.

[0075] Next, a control method for power conduction rate C of refrigerator 10 will be described with reference to Fig. 5. As shown in the figure, the control method for power conduction rate C is used when water supply tank 31 is not empty and the operation status of refrigerator 10 satisfies Condition 2. Steps S50 to S62 in Fig. 5 correspond to the control method for power conduction rate C.

[0076] In step S50, control unit 40 determines that the first water supply operation to ice tray 32 has not been performed based on the detection signal from infrared sensor 44. Next, in step S51, control unit 40 determines based on the detection signal from door opening / closing sensor 43 whether or not insulation door 18 of refrigerator compartment 12 has been opened.

[0077] If the control unit 40 determines at NO in step S51 that the insulated door 18 of the refrigerator compartment 12 is not open without receiving the above detection signal, the control unit 40 determines at step S52 whether the compressor 23 is operating or not.

[0078] If the control unit 40 determines that the compressor 23 is operating at YES in step S52, then in step S53 the control unit 40 energizes the heating unit 36 ​​at a power supply rate of 30%. On the other hand, if the control unit 40 determines that the compressor 23 is stopped at NO in step S52, then in step S54 the control unit 40 energizes the heating unit 36 ​​at a power supply rate of 25%.

[0079] In step S55, control unit 40 determines whether or not 70 minutes have passed since the start of the previous supply of water to ice tray 32, based on the detection signal from timer 41. Then, if control unit 40 determines that 70 minutes have passed since the start of the previous supply of water to ice tray 32 (YES in step S55), the process proceeds to step S56, where control unit 40 increases the power supply rate to heating unit 36 ​​to 100% and continues power supply.

[0080] In step S57, control unit 40 determines whether or not 85 minutes have passed since the start of the previous water supply to ice tray 32, based on the detection signal from timer 41. Then, if control unit 40 determines that 85 minutes have passed since the start of the previous water supply to ice tray 32 (YES in step S57), the process proceeds to step S58, where control unit 40 reduces the power supply rate to heating unit 36 ​​to 50% and continues power supply.

[0081] In step S59, control unit 40 determines whether or not a set time (120 minutes for one cycle) has elapsed since the previous start of water supply to ice tray 32 based on the detection signal from timer 41. Then, if control unit 40 determines that the set time has elapsed since the previous start of water supply to ice tray 32 (YES in step S59), the process proceeds to step S60, where control unit 40 checks ice in ice storage container 33 and removes ice from ice tray 32 via ice maker 37, and then supplies water to ice tray 32.

[0082] On the other hand, if the control unit 40 determines that the set time has not elapsed since the last time water supply to ice tray 32 started at NO in step S59, if the control unit 40 determines that 70 minutes have not elapsed since the last time water supply to ice tray 32 started at NO in step S55, or if the control unit 40 determines that 85 minutes have not elapsed since the last time water supply to ice tray 32 started at NO in step S57, the process returns to step S51.

[0083] In step S61, control unit 40 determines whether or not a second water supply operation has been performed to ice tray 32 from the detection signal from infrared sensor 44. Then, if control unit 40 determines that a second water supply operation has not been performed to ice tray 32 (NO in step S61), the process proceeds to step S10, and control unit 40 starts controlling current supply rate A.

[0084] If control unit 40 determines that the water supply operation to ice tray 32 has been performed (YES in step S61), the process proceeds to step S33, and control unit 40 starts the ice making operation by controlling current conduction rate B.

[0085] If the control unit 40 determines in step S51 that the insulated door 18 of the refrigerator compartment 12 is open, the process proceeds to step S62, where the control unit 40 determines whether the insulated door 18 of the refrigerator compartment 12 has been closed, based on a detection signal from the door open / close sensor 43. If the control unit 40 determines in step S62 that the insulated door 18 of the refrigerator compartment 12 has been closed, the process proceeds to step S33, where the control unit 40 starts ice-making operation by controlling the power conduction rate B ... has been closed, the process proceeds to step S33.

[0086] As described above, in the method of controlling the power supply rate A in refrigerator 10 of this embodiment, when control unit 40 determines that condition 3 is met after detecting that water supply tank 31 is empty twice in succession, control unit 40 determines that water supply tank 31 is empty, i.e., that water supply tray 32 has not been supplied with water twice in succession despite water supply pipe 35 being heated, and water supply tank 31 has no water, i.e., that water supply tank 31 is in an empty state. In this case, ice making operation is not performed until the user supplies water into water supply tank 31, so power supply to heating unit 36 ​​is stopped, and the amount of power consumed by refrigerator 10 is reduced.

[0087] In addition, in the control method of the power conduction rate D, when it is detected that the insulated door 18 of the refrigerator compartment 12 has been opened or closed, it is possible that the user has supplied water to the water supply tank 31, so by passing electricity through the heating section 36 at a high power conduction rate for a short period of time, the water supply pipe 35 is prevented from freezing, and blockage due to frozen water in the water supply pipe 35 is prevented during the water supply operation.

[0088] In the control method for power supply rate B, the power supply rate to heating unit 36 ​​is lowered to a level at which the water in water supply pipe 35 does not freeze until 70 minutes have passed since ice tray 32 was supplied with water, and the power supply rate to heating unit 36 ​​is increased again 70 minutes after ice tray 32 was supplied with water. This control method prevents blockage due to freezing of water remaining in water supply pipe 35 by continuing to supply power to heating unit 36. Furthermore, by temporarily lowering the power supply rate to heating unit 36, water supply pipe 35 does not maintain a high temperature state, preventing bacteria from growing in the water remaining in water supply pipe 35, and reducing the amount of power consumed by refrigerator 10.

[0089] In the control method of power supply rate C, the power supply rate of heating unit 36 ​​is maximized once after the first empty detection of water supply tank 31, and then the power supply rate is reduced 15 minutes later. During the manufacturing process of refrigerator 10, there is a possibility that the water in water supply pipe 35 may freeze and cause blockage due to various factors such as variations in the assembly position of water supply pipe 35 and heating unit 36, variations in the length of water supply pipe 35, variations in the assembly of each component of refrigerator 10, and the amount of water remaining in water supply pipe 35 during ice-making operation.

[0090] With the above control method, even if the water in the water supply pipe 35 freezes, the frozen state can be melted by maximizing the power supply rate of the heating unit 36. Then, the phenomenon in which the water supply pipe 35 is blocked by frozen water and water cannot be supplied to the ice tray 32 even though the water supply tank 31 is filled with water is prevented. Meanwhile, the control unit 40 can determine that the water supply tank 31 is empty, not that the water supply pipe 35 is blocked by freezing. Also, by preventing the power supply rate of the heating unit 36 ​​from being maximized for a long period of time, the proliferation of the bacteria is prevented, and the power consumption of the refrigerator 10 is reduced.

[0091] Finally, as shown in Figures 2(A) and (B) , in the operation of supplying water to ice tray 32 in this embodiment, control unit 40 operates motor 45 in the reverse direction, then in the forward direction, and finally in the reverse direction, so that water supply pump 34 draws water from water supply tank 31 and then supplies the drawn water to ice tray 32 via water supply pipe 35.

[0092] With this control method, even if water melted by heating by the heating unit 36 ​​remains near the tip of the water supply pipe 35 due to surface tension before the water supply operation, the motor 45 is first operated in the reverse direction to suck up the water near the tip of the water supply pipe 35 and to allow air to flow through the water supply pipe 35. Then, when the motor 45 is operated in the forward direction, the air inside the water supply pipe 35 is compressed, preventing the water at the tip from splashing into the ice tray 32 in a bumping manner. Finally, the motor 45 is operated in the reverse direction to prevent the siphoning phenomenon from occurring.

[0093] In this embodiment, the infrared sensor 44 detects the bottom temperature of the ice tray 32, and the control unit 40 judges the presence or absence of water in the water supply tank 31 based on the detection signal, but the present invention is not limited to this. For example, after detecting the current waveform of the water supply pump 34, it is converted into a voltage value via a resistor, and the voltage value is compared with a preset threshold value. Then, the control unit 40 may detect whether water has been discharged from the water supply pump 34 based on the comparison result, and judge the presence or absence of water in the water supply tank 31 based on the detection signal. In addition, various modifications are possible within the scope of the present invention. [Explanation of symbols]

[0094] 10. Refrigerator 11 Insulated box 12 Refrigerator 13 Freezer 23 Compressor 25 Blower 27 Insulated Partition Wall 30 Ice maker 31 Water tank 32 Ice tray 33 Ice storage container 34 Water Pump 35 Water Supply Pipe 36 Heating section 40 Control section 42 Internal temperature sensor 43 Door opening / closing sensor 44 Infrared Sensor

Claims

1. A water tank for storing water; An ice tray for making ice out of the water; An ice maker that removes ice made in the ice tray; a water supply pump that draws the water from within the water supply tank; a water supply pipe that sends the water sucked by the water supply pump to the ice tray; A heating unit that heats the water supply pipe; a control unit that determines whether or not the water is present in the water supply tank and variably controls a power supply rate to the heating unit, The control unit sets a power supply rate to the heating unit before the water supply pump is operated to be higher than a power supply rate to the heating unit after the water supply pump is operated.

2. 2. The refrigerator according to claim 1, wherein the control unit determines that the water supply tank is empty for a first time, and after a certain time has elapsed since the power supply rate to the heating unit was maximized, reduces the power supply rate to the heating unit and determines for a second time whether water is present in the water supply tank.

3. 3. The refrigerator according to claim 2, wherein the control unit stops the supply of electricity to the heating unit after determining that the water tank is empty twice in succession and further determining that an insulated door that opens and closes the interior in which the water tank is disposed has not been opened.

4. 3. The refrigerator according to claim 2, wherein the control unit, after determining that the water supply tank is empty twice in succession and further determining that an insulated door that freely opens and closes an interior in which the water supply tank is disposed has opened or closed, reduces the power supply rate to the heating unit after the certain time has elapsed since the power supply rate to the heating unit was maximized, and then drives the water supply pump.

5. A compressor that constitutes a refrigeration cycle, The refrigerator according to any one of claims 1 to 4, wherein the control unit increases the power supply rate to the heating unit when the compressor is operating, more than when the compressor is stopped.

6. The refrigerator according to any one of claims 1 to 5, characterized in that, when driving the water supply pump, the control unit first operates the motor that drives the water supply pump in a reverse direction, then operates it in a forward direction, and finally operates it in the reverse direction again.

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