Ice maker
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- HOSHIZAKI ELECTRIC CO LTD
- Filing Date
- 2024-12-25
- Publication Date
- 2026-07-07
Smart Images
Figure 2026112517000001_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to an ice maker that manufactures ice in an ice-making unit provided in an ice-making and ice-storing refrigerator, and when the ice-making and ice-storing refrigerator is filled with ice, the ice-making unit waits for ice production, and the ice-making unit is cooled by a refrigeration device to keep the inside of the ice-making and ice-storing refrigerator cold. The present invention relates to an ice maker capable of performing a cold-keeping operation.
Background Art
[0002] Patent Document 1 discloses an invention of an ice maker that manufactures ice in an ice-making unit provided in an ice-making chamber. This ice maker includes an ice-making unit that freezes ice-making water to produce ice, a cooling operation that cools the ice-making unit by evaporating the refrigerant pumped from a compressor and condensed by a condenser by an evaporator provided in the ice-making unit, and a heating operation that heats the ice-making unit by sending hot gas refrigerant from the compressor to the evaporator. It also includes a refrigeration device capable of performing, a water supply means for sending ice-making water to the ice-making unit, an ice-making chamber in which the ice-making unit is disposed, a storage chamber disposed below the ice-making chamber for storing the ice produced by the ice-making unit, and a storage ice detector for detecting that the storage chamber is filled with ice.
[0003] In this ice maker, when performing an ice-making operation of freezing ice-making water in the ice-making unit to produce ice, the ice-making water is frozen in the ice-making unit cooled by cooling the refrigeration device to form ice. Also, when performing a defrosting operation after the ice-making operation, the ice is detached from the ice-making unit heated by heating the refrigeration device. By alternately repeating the ice-making operation and the defrosting operation, ice can be stored in the storage chamber.
[0004] In this ice maker, when the ice storage detector does not detect that the ice storage chamber is full of ice, it operates in ice-making mode, alternating between ice-making and de-icing operations to produce ice for storage in the chamber. When the ice storage detector detects that the ice storage chamber is full of ice, it switches to ice-storage mode, controlling the machine to not perform ice-making or de-icing operations, and remains in standby mode without producing ice for storage. When switching from ice-making mode to ice-storage mode, the refrigeration system is activated to cool the ice-making section, enabling a cooling operation to cool both the ice-making and ice-storage chambers. The ice-making and ice-storage chambers are kept cool by the cold air generated from the ice-making section cooled by the refrigeration system. [Prior art documents] [Patent Documents]
[0005] [Patent Document 1] Japanese Patent Publication No. 2024-054945 [Overview of the project] [Problems that the invention aims to solve]
[0006] In the ice maker described in Patent Document 1, when the machine switches from ice-making mode to ice-storage mode (standby mode), it is possible to perform a cooling operation to cool the ice-making section by operating the refrigeration unit, thereby cooling the inside of the ice-making chamber and ice-storage chamber (ice-making and ice-storage compartment). The compressor of the refrigeration unit has a minimum operating time and a minimum stopping time set to prevent short-term starting and stopping (operation and stopping). Therefore, when the cooling operation is started under conditions of low outside temperature or when the temperature inside the ice-making chamber and ice-storage compartment is low, even if the cooling operation is performed for the minimum operating time of the compressor of the refrigeration unit, there is a risk that the inside of the ice-storage compartment may be overcooled. One example of a problem caused by overcooling of the ice-storage compartment is the occurrence of so-called arching, where multiple ice cubes inside the ice-storage compartment fuse together. The present invention aims to make it less likely for problems to occur due to overcooling inside the ice-making and ice-storage compartment to occur in an ice maker that is capable of keeping the inside of the ice-making and ice-storage compartment cool. [Means for solving the problem]
[0007] To solve the above problems, the present invention provides a refrigeration system that includes an ice-making unit that freezes ice-making water to produce ice, a cooling operation that cools the ice-making unit by evaporating a refrigerant, which is pumped from a compressor and condensed in a condenser, in an evaporator provided in the ice-making unit, and a heating operation that heats the ice-making unit by sending hot gas refrigerant from the compressor to the evaporator, an ice-making storage compartment in which the ice-making unit is located above and which forms a space for storing ice produced in the ice-making unit, and an ice storage detector that detects when the ice-making storage compartment is full of ice, wherein when the ice storage detector does not detect that the ice-making storage compartment is full of ice, the refrigeration system is operated in ice-making mode to cool the ice-making unit and freeze the ice-making water to produce ice. This ice maker produces ice to be stored in an ice storage compartment by alternately performing an ice-making operation and a de-icing operation that separates the ice from the heated ice-making section by heating the refrigeration system after the ice-making operation. When an ice storage detector detects that the ice storage compartment is full of ice, the ice maker is controlled to enter a standby mode, where it does not perform ice-making or de-icing operations, and waits without producing ice to be stored in the ice storage compartment. In the standby mode, it is possible to perform a cooling operation to cool the ice-making section by cooling the refrigeration system, and the ice maker is characterized in that it is controlled to temporarily enable heating when the cooling operation of the refrigeration system is being performed by the cooling operation in the standby mode.
[0008] In the ice maker configured as described above, the system is controlled to temporarily enable heating operation while the refrigeration unit is performing a cooling operation during standby mode. Even if the cooling operation is started under conditions of low ambient temperature or low temperature inside the ice storage compartment, controlling the system to temporarily enable heating operation while the refrigeration unit is performing a cooling operation during the cooling operation prevents the ice storage compartment from being overcooled without having to start and stop the compressor, which is a component of the refrigeration unit, for a short period of time. This reduces the likelihood of arching, a problem where multiple ice cubes fuse together, which is one example of a problem caused by overcooling inside the ice storage compartment. [Brief explanation of the drawing]
[0009] [Figure 1] This is a perspective view of the ice maker of the present invention. [Figure 2] This is a schematic diagram of the ice maker of the present invention. [Figure 3] This is a schematic diagram showing the ice-making section and water tray. [Figure 4] This is a block diagram of the control device. [Figure 5] This is a time chart for when ice-making mode and standby mode are running. [Modes for carrying out the invention]
[0010] An embodiment of the ice maker of the present invention will be described below with reference to the drawings. As shown in Figures 1 and 2, the ice maker 10 of the present invention is a so-called closed-cell type ice maker, and is equipped with an ice-making storage compartment 12 and a machine room 17 within a housing 11. The ice-making storage compartment 12 is equipped with an ice-making chamber 13 at the top where the ice-making mechanism 20 and the ice-making unit 21 are located to produce ice, and an ice-storage chamber 14 below the ice-making chamber 13 for storing the ice produced by the ice-making unit 21. The inside of the ice-making storage compartment 12 is partitioned by a drain pan (partition) 15 to allow ice and cold air to pass through. An insulating member (not shown) is provided on the outer surface of the ice-making storage compartment 12, and the ice-making storage compartment 12 is covered in an insulating state by the insulating member.
[0011] As shown in Figure 1, the front of the ice storage chamber 14 of the ice-making and ice storage unit 12 has two outlets 12a and 12b, which are openings used for taking out ice, and the outlets 12a and 12b are closed by a door 16 that can be opened and closed. In this embodiment, the door 16 has a first door 16a that can be opened and closed to close the upper outlet 12a, and a second door 16b that can be opened and closed to close the lower outlet 12b. The first door 16a uses two sliding doors and is supported on the upper front of the ice storage chamber 14 so as to be movable from side to side. The second door 16b uses a hinged door and its lower end is supported on the lower front of the ice storage chamber 14 so as to be rotatable around a horizontal axis. The machine room 17 is located on the upper part of the housing 11, adjacent to the ice-making chamber 13 in the horizontal direction, and contains mechanical parts such as the refrigeration device 30, excluding the evaporator 34 of the ice-making mechanism 20. In Figure 1, the ice in the ice storage chamber 14 is shown by a dashed line.
[0012] As shown in Figure 2, the ice maker 10 is equipped with an ice-making mechanism 20 that produces ice. The ice-making mechanism 20 includes an ice-making unit 21 that freezes ice-making water to produce ice, a refrigeration device 30 capable of cooling and heating the ice-making unit 21, and a water supply means 22 that supplies ice-making water to the ice-making unit 21. The ice-making unit 21 is located inside the ice-making chamber 13 and is a shallow, box-shaped structure with an open bottom. A grid-like partition member is provided inside the box to form multiple ice-making compartments 21a that open to the bottom. Ice-making water is sprayed into each ice-making compartment 21a from below, and block-shaped ice is formed inside each ice-making compartment 21a as the ice-making water freezes.
[0013] As shown in Figures 2 and 3, an evaporator 34, which constitutes the refrigeration system 30, is located on the upper surface of the ice-making unit 21. The refrigeration system 30 is capable of cooling or heating the ice-making unit 21 through cooling and heating operations, and is located in the machine room 17, except for the evaporator 34 which is located above the ice-making unit 21 in the ice-making chamber 13. As shown in Figure 2, the refrigeration system 30 includes a compressor 31 that compresses the refrigerant, a condenser 32 that cools and liquefies the refrigerant pumped from the compressor 31, an expansion valve 33 that expands the liquefied refrigerant liquefied in the condenser 32 to produce low-pressure liquefied refrigerant, and an evaporator 34 that vaporizes the liquefied refrigerant expanded by the expansion valve 33 to cool the ice-making unit 21. The refrigeration system 30 is configured as a refrigeration circuit by connecting the compressor 31, condenser 32, expansion valve 33, and evaporator 34 in a ring shape with refrigerant pipes. When the refrigeration unit 30 is put into cooling operation, the refrigerant pumped from the compressor 31 is cooled in the condenser 32 to become liquefied refrigerant. The liquefied refrigerant then becomes low-pressure liquefied refrigerant in the expansion valve 33, and the heat of vaporization generated when the low-pressure liquefied refrigerant evaporates in the evaporator 34 cools the ice-making unit 21.
[0014] To prevent repeated short-term starting and stopping (operation and deactivation), the compressor 31 has a minimum operating time (3 minutes in this embodiment) and a minimum stopping time (3 minutes in this embodiment). Therefore, in the cooling operation described later, a cooling operation time is set in which the refrigeration device 30 is operated to maintain cooling, and a cooling standby time is set in which the refrigeration device 30 is kept inactive, taking into account the minimum operating time and minimum stopping time of the compressor 31. The condenser 32 is equipped with a condenser fan 32a, and the refrigerant passing through the condenser 32 is cooled by the air blown by the condenser fan 32a. The condenser 32 is equipped with a condenser temperature sensor 32b, which is used to detect the temperature of the refrigerant passing through the condenser 32. The evaporator 34 is made of a tubular material with high thermal conductivity and is arranged in a meandering manner above the ice-making unit 21.
[0015] Furthermore, the refrigeration system 30 is equipped with a hot gas pipe (hot gas path) 35 that supplies hot gas to the evaporator 34. The hot gas pipe 35 connects the downstream of the compressor 31 and the upstream of the evaporator 34, guiding the hot gas from the compressor 31 to the evaporator 34. A hot gas valve 36 is interposed in the hot gas pipe 35, and the hot gas valve 36 allows the hot gas pipe 35 to be opened and closed. When the refrigeration system 30 is operated in heating mode, the hot gas sent from the compressor 31 is guided to the evaporator 34 by the opening of the hot gas valve 36, and the hot gas heats the ice-making section 21 as it passes through the evaporator 34. In this way, the ice-making section 21 is cooled by the evaporation of the refrigerant circulating in the evaporator 34 during the cooling operation of the refrigeration system 30, and heated by the hot gas sent from the compressor 31 to the evaporator 34 during the heating operation of the refrigeration system 30.
[0016] As shown in Figure 2, a water supply means 22 for supplying ice-making water is provided below the ice-making unit 21. The water supply means 22 includes a water tray 23 that can be opened and closed to close the lower side of the ice-making chamber 21a of the ice-making unit 21, a tank 24 that stores ice-making water below the water tray 23, and a water supply pump 25 that supplies the ice-making water from the tank 24 to the ice-making unit 21. The water tray 23, tank 24, and water supply pump 25 are arranged inside the ice-making chamber 13, similar to the ice-making unit 21. The water tray 23 is pivotally supported so as to be able to tilt around a horizontal axis between a closed position that closes the lower side of the ice-making chamber 21a (shown by the solid line in Figure 2) and an open position that opens the lower side of the ice-making chamber 21a (shown by the dashed line in Figure 2). The water tray 23 is provided with an opening / closing mechanism 26, and the water tray 23 tilts between a closed position and an open position by the drive of the actuator motor 26a of the opening / closing mechanism 26, thereby opening and closing the lower side of the ice-making chambers 21a. As shown in Figure 3, the water tray 23 has an ice-making water passage 23a for sending ice-making water from the tank 24 to each ice-making chamber 21a, and the upper surface of the water tray 23 has injection holes 23b for injecting ice-making water from the ice-making water passage 23a into each ice-making chamber 21a.
[0017] As shown in Figure 2, the ice-making mechanism 20 is equipped with a water supply means 27 that supplies water to the tank 24. The water supply means 27 includes a water supply pipe 27a that supplies water from a water source such as a tap as ice-making water, and a water supply valve 27b interposed in the water supply pipe 27a. The water inlet at the end of the water supply pipe 27a is located above the water tray 23, and the water from the water source is sent above the water tray 23 and sent into the tank 24 through a return port (not shown) formed in the water tray 23. The ice-making water in the tank 24 is sent to the ice-making water passage 23a of the water tray 23 by a water supply pump 25, and the ice-making water sent to the ice-making water passage 23a is injected into the ice-making chamber 21a from the injection hole 23b. The sprayed ice-making water is cooled in the ice-making chamber 21a and then returns to the tank 24 through the return port. The ice-making water circulates between the tank 24 and the ice-making chamber 21a, where it is cooled and freezes into ice within the ice-making chamber 21a.
[0018] As shown in Figure 2, a drain pan 15 is provided on the lower side of the tank 24. The drain pan 15 prevents dripping water from the ice-making mechanism 20 from falling into the ice storage chamber and also receives the ice-making water remaining in the tank 24 after ice-making operation. A drain pipe (not shown) is connected to the drain pan 15, and the ice-making water received in the drain pan 15 is discharged to the outside of the housing 11 through the drain pipe. The drain pan 15 also covers the lower side of the ice-making unit 21 and the water supply means 22, and functions as a partition separating the ice-making chamber 13 and the ice storage chamber 14, with a discharge port 15a for discharging ice produced by the ice-making unit 21 into the ice storage chamber 14. The discharge port 15a is an opening formed in the drain pan 15, and in this embodiment, it is formed at a position to the right of the center of the ice-making chamber 13 in the left-right direction, and spaced apart from the front and rear of the ice-making chamber 13.
[0019] As shown in FIG. 2, an ice-making unit temperature sensor 41 is provided in the ice-making unit 21. By detecting the temperature of the ice-making unit 21, the ice-making unit temperature sensor 41 can detect the completion of ice-making in the ice-making operation and the completion of defrosting in the defrosting operation, which will be described later. A storage ice detector 42 for detecting that the storage chamber 14 of the ice-making and storage refrigerator 12 is filled with ice is provided in the storage chamber 14 of the ice-making and storage refrigerator 12. The storage ice detector 42 is arranged across the discharge port 15a so as to extend from the ice-making chamber 13 to the storage chamber 14, and detects the ice accumulated in the upper part of the storage chamber 14 below the discharge port 15a to detect that the storage chamber 14 is filled with ice. A temperature sensor 43 inside the refrigerator is provided in the storage chamber 14 of the ice-making and storage refrigerator 12, and the temperature sensor 43 inside the refrigerator can detect the temperature inside the ice-making and storage refrigerator 12.
[0020] The ice maker 10 includes a control device 50. As shown in FIG. 4, this control device 50 is connected to a water supply pump 25, an actuator motor 26a of an opening and closing mechanism 26, a water supply valve 27b, a compressor 31, a condenser fan 32a, a condenser temperature sensor 32b, a hot gas valve 36, an ice-making unit temperature sensor 41, a storage ice detector 42, and a temperature sensor 43 inside the refrigerator. The control device 50 has a microcomputer (not shown), and the microcomputer includes a CPU, a RAM, a ROM, and a timer (all not shown) respectively connected via a bus. The control device 50 has an ice-making program for alternately repeating an ice-making operation for freezing ice-making water in the ice-making unit 21 to produce ice and a defrosting operation for removing the ice frozen in the ice-making unit 21 by the ice-making operation.
[0021] As shown in FIG. 5, when the control device 50 does not detect that the storage chamber 14 of the ice-making and storage refrigerator 12 is filled with ice by the storage ice detector 42, it executes an ice-making program that alternately repeats the ice-making operation and the defrosting operation as an ice-making mode to produce ice to be stored in the storage chamber 14. When the control device 50 detects that the storage chamber 14 is filled with ice by the storage ice detector 42, it waits without executing the ice-making program that alternately repeats the ice-making operation and the defrosting operation as a standby mode. During this standby mode, the control device 50 controls the operation of the refrigeration device 30 to enable the execution of a cold storage operation for cooling the inside of the ice-making and storage refrigerator 12.
[0022] The ice-making operation cools the ice-making section 21 by cooling the refrigeration device 30 with the water tray 23 in the closed position, and the water in the tank 24 is ejected and sent from the injection holes 23b of the water tray 23 to the ice-making chamber 21a of the ice-making section 21 by the water pump 25, and while being cooled in the ice-making chamber 21a, it is returned to the tank 24, and the water in the tank 24 is circulated between the inside of the ice-making chamber 21a and frozen in the ice-making chamber 21a to produce ice. The defrosting operation warms the ice-making section 21 by warming the refrigeration device 30 with the water tray 23 in the open position, and melts the ice produced in the ice-making chamber 21a of the ice-making section 21 at the contact surface with the ice-making chamber 21a and causes it to detach from the ice-making chamber 21a.
[0023] The cold storage operation aims to keep the inside of the ice-making chamber 13 of the ice-making and ice-storing cabinet 12 at a low temperature to suppress the growth of microorganisms such as bacteria, and to prevent the so-called arching where a plurality of ice stored in the ice storage chamber 14 of the ice-making and ice-storing cabinet 12 freezes and binds, and to store the ice so that it does not melt. The cold storage operation cools the ice-making section 21 by the cooling operation (operation) of the refrigeration device 30, and the cooled ice-making section 21 cools the ice-making chamber 13 and the ice storage chamber 14 of the ice-making and ice-storing cabinet 12. By performing the cold storage operation, the inside of the ice-making chamber 13 is cooled by the cooled ice-making section 21 by the cooling operation of the refrigeration device 30, and further, the inside of the ice storage chamber 14 is cooled by the cold air flowing down from the inside of the ice-making chamber 13. The inside of the ice-making chamber 13 is kept at a low temperature by the cooled ice-making section 21, suppressing the growth of microorganisms such as bacteria and becoming hygienic, and the inside of the ice storage chamber 14 can prevent the melting of ice by the cold air flowing down through the discharge port 15a from the inside of the ice-making chamber 13.
[0024] The cooling operation is controlled to be performed based on the temperature detected by the internal temperature sensor 43, which detects the temperature inside the ice maker / storage compartment 12 during standby mode. In this embodiment, the cooling operation is controlled to be performed when the calculated internal cumulative average temperature, which is the average value per unit time of the cumulative values obtained by accumulating the temperatures detected by the internal temperature sensor 43 over time during standby mode, is equal to or greater than the cooling set temperature. Furthermore, the cooling operation is controlled to be performed for a cooling operation time (e.g., 3 to 5 minutes) that is set to be equal to or greater than the minimum operating time of the compressor 31. Alternatively, the cooling operation may be controlled to be performed when the temperature detected by the internal temperature sensor 43 is equal to or greater than the cooling set temperature.
[0025] As mentioned above, although the cooling operation is controlled to run for a set duration that is longer than the minimum operating time of the compressor 31, when the ambient temperature at the installation location of the ice maker 10 is low, there is a risk that the ice storage chamber 14 of the ice maker storage unit 12 may be excessively cooled by the cooling operation. There is a risk that arching, the formation of multiple ice crystals in the ice storage chamber 14 of the ice maker storage unit 12, may occur. For this reason, in this ice maker 10, the heating operation is temporarily enabled when the cooling operation of the refrigeration unit 30 is being performed by the cooling operation during standby mode.
[0026] When the refrigeration unit 30 is operated in cooling mode, the refrigerant pumped from the compressor 31 is liquefied in the condenser 32 to become liquefied refrigerant. The liquefied refrigerant expands in the expansion valve 33 to become low-pressure liquefied refrigerant. The low-pressure liquefied refrigerant vaporizes in the evaporator 34 and returns to the compressor 31. The ice-making unit 21 is cooled by the vaporization of the liquefied refrigerant in the evaporator 34. The cold air generated in the ice-making unit 21 flows into the ice storage room 14 while cooling the inside of the ice-making chamber 13. Even if the inside of the ice storage room 14 of the ice-making and ice storage unit 12 is sufficiently cooled within the cooling operation time, the compressor 31 has a minimum operating time set, so it is not possible to stop the operation of the compressor 31 and stop the cooling operation within the cooling operation time.
[0027] Therefore, in order to prevent the ice storage chamber 14 of the ice-making storage unit 12 from being excessively cooled, the cooling operation of the refrigeration unit 30 is temporarily changed to a heating operation. By controlling the hot gas valve 36 to be open for a certain period of time (for example, 30 seconds) while the compressor 31 continues to operate, the hot gas sent from the compressor 31 is guided to the evaporator 34 through the hot gas pipe 35 and heats the ice-making unit 21. After a certain period of time, the hot gas valve 36 is closed, and the liquefied refrigerant liquefied in the condenser 32 is sent again to the evaporator 34 of the ice-making unit 21, and the ice-making unit 21 is cooled by the liquefied refrigerant vaporizing again in the evaporator 34. In this way, by temporarily flowing hot gas to the evaporator 34 without stopping the compressor 31, it is possible to prevent the ice-making unit 21 from being excessively cooled, and thus prevent the inside of the ice-making storage unit 12 from being excessively cooled.
[0028] In addition, the control to temporarily change the cooling operation of the refrigeration unit 30 to a heating operation is performed at a predetermined timing within the refrigeration operation time (for example, at an intermediate timing within the refrigeration operation time). Alternatively, the control may be set to open the hot gas valve 36 for a certain period of time and perform a heating operation based on the temperature detected by the internal temperature sensor 43 that detects the temperature inside the ice-making storage unit 12 (when the temperature detected by the internal temperature sensor 43 falls below a predetermined lower limit). Similarly, the control may be set to open the hot gas valve 36 for a certain period of time and perform a heating operation based on the temperature detected by the ice-making unit temperature sensor 41 that detects the temperature inside the ice-making unit 21 (when the temperature detected by the ice-making unit temperature sensor 41 falls below a predetermined lower limit).
[0029] Next, the ice-making program executed during ice-making mode will be described. As shown in Figure 5, when the control device 50 executes the ice-making program during ice-making mode, the ice-making unit 21 repeatedly performs ice-making and de-icing operations alternately. When the control device 50 performs ice-making operation, it cools the refrigeration unit 30, causing the refrigerant pumped from the compressor 31 to be liquefied in the condenser 32, which then expands in the expansion valve 33 to become low-pressure liquefied refrigerant. This low-pressure liquefied refrigerant vaporizes in the evaporator 34 and returns to the compressor 31, and the ice-making unit 21 is cooled by the vaporization of the liquefied refrigerant in the evaporator 34. In addition, the control device 50 tilts the water tray 23 to the closed position using the actuator motor 26a of the opening / closing mechanism 26, and opens the water supply valve 27b for a predetermined time according to the capacity of the tank 24, thereby storing the amount of ice-making water necessary to form ice in the ice-making unit 21 in the tank 24.
[0030] When the control device 50 operates the water supply pump 25 while the refrigeration unit 30 is in cooling operation, the ice-making water in the tank 24 is sprayed into each ice-making chamber 21a of the ice-making unit 21 by the operation of the water supply pump 25. The sprayed ice-making water is cooled in each ice-making chamber 21a and returns to the tank 24, and as the ice-making water circulates between the tank 24 and each ice-making chamber 21a, it is cooled and gradually freezes in each ice-making chamber 21a. When the amount of ice-making water in the tank 24 decreases and the ice-making water freezes in each ice-making chamber 21a to form block-shaped ice, and the temperature detected by the ice-making unit temperature sensor 41 falls below the ice-making completion temperature, the control device 50 terminates the ice-making operation and starts the de-icing operation.
[0031] During the de-icing operation after the ice-making operation, the control device 50 opens the hot gas valve 36 while the compressor 31 is operating, causing the refrigeration unit 30 to heat up, and the actuator motor 26a of the opening / closing mechanism 26 tilts the water tray 23 to the open position. When the refrigeration unit 30 is heated, the hot gas sent from the compressor 31 is guided through the hot gas pipe 35 to the evaporator 34, heating each of the ice-making compartments 21a of the ice-making unit 21. The temperature of the ice-making unit 21 gradually rises due to the hot gas introduced into the evaporator 34, and the ice frozen in each of the ice-making compartments 21a detaches, slides down the top surface of the water tray 23, and falls into the ice storage chamber 14 through the discharge port 15a. As the ice-making unit 21 gradually rises as the ice detaches, the control device 50 detects that there is no ice remaining in the ice-making chamber 21a of the ice-making unit 21, i.e., that de-icing is complete, and closes the hot gas valve 36 to end the de-icing operation. If the ice storage detector 42 has not detected that the ice storage chamber 14 is filled with ice, the control device 50 restarts the ice-making program which alternates between ice-making and de-icing operations as described above. In this way, the control device 50 controls the ice-making program to alternate between ice-making and de-icing operations in ice-making mode until the ice storage detector 42 detects that the ice storage chamber 14 is filled with ice.
[0032] When the system is controlled to execute an ice-making program that alternates between ice-making and de-icing operations, the ice-making compartment 14 of the ice-making storage unit 12 will be filled with ice produced by the ice-making unit 21. When the ice-storage detector 42 detects that the ice-storage compartment 14 is full of ice (when the ice-storage detector 42 turns ON (full) in Figure 5), the control device 50 terminates the ice-making mode and switches to standby mode, controlling the system to remain in standby mode without executing the ice-making program that alternates between ice-making and de-icing operations.
[0033] As shown in Figure 5, the control device 50 controls the system to perform a cooling operation when the standby mode starts, transitioning from the ice-making mode, if the temperature detected by the internal temperature sensor 43 is equal to or higher than the set cooling temperature (11°C in this embodiment) set as the temperature for cooling the inside of the ice-making and ice storage compartment 12. When the refrigeration system 30 performs a cooling operation in the cooling operation, the refrigerant pumped from the compressor 31 is liquefied in the condenser 32 to become liquefied refrigerant, which expands in the expansion valve 33 to become low-pressure liquefied refrigerant, which vaporizes in the evaporator 34 and returns to the compressor 31, and the ice-making unit 21 is cooled by the vaporization of the liquefied refrigerant in the evaporator 34. The cold air generated in the ice-making unit 21 flows down into the ice storage compartment 14 while cooling the inside of the ice-making compartment 13.
[0034] After a predetermined time has elapsed since the start of the cooling operation of the refrigeration unit 30 under the cooling operation, the cooling operation of the refrigeration unit 30 is temporarily changed to a heating operation. By controlling the hot gas valve 36 to be open for a certain period of time (for example, 30 seconds) while the compressor 31 continues to operate, the hot gas sent from the compressor 31 is guided to the evaporator 34 through the hot gas pipe 35 and heats the ice-making unit 21. After a certain period of time, the hot gas valve 36 is closed, and the liquefied refrigerant liquefied in the condenser 32 is sent again to the evaporator 34 of the ice-making unit 21, and the ice-making unit 21 is cooled by the liquefied refrigerant vaporizing again in the evaporator 34. In this way, the ice-making unit 21 is not overcooled during the cooling operation, and so-called arching, in which multiple ice cubes fuse together, which is a problem caused by excessive cooling inside the ice storage chamber 14 of the ice-making storage unit 12, is less likely to occur.
[0035] After the cooling operation is performed in standby mode, the control device 50 starts calculating the cumulative average temperature inside the storage unit, which is the average value per unit time of the cumulative values obtained by accumulating the temperatures detected by the internal temperature sensor 43 over time. The temperature inside the ice maker and ice storage unit 12 gradually rises after the cooling operation, and the cumulative average temperature inside the storage unit also gradually rises. After the minimum operating stop time (10 minutes in this embodiment), which is set to be longer than the minimum operating time of the compressor 31, has elapsed, and the cumulative average temperature inside the storage unit is equal to or higher than the cooling set temperature, the control device 50 controls the unit to perform the cooling operation again. In this way, during standby mode, the control device 50 controls the unit to perform the cooling operation based on the cumulative average temperature inside the storage unit, which is the average value per unit time of the cumulative values obtained by accumulating the temperatures detected by the internal temperature sensor 43 over time, and the inside of the ice maker and ice storage unit 12 is cooled by performing the cooling operation during standby mode. Furthermore, the calculation of the cumulative average internal temperature, which is the average value per unit time of the cumulative values obtained by accumulating the temperatures detected by the internal temperature sensor 43 over time, is not limited to starting after the cooling operation in standby mode has been performed. It is also possible to start calculating the cumulative average internal temperature, which is the average value per unit time of the cumulative values obtained by accumulating the temperatures detected by the internal temperature sensor 43 over time, from the start of the cooling operation in standby mode.
[0036] As described above, the ice maker 10, when the ice storage detector 42 does not detect that the ice storage chamber 14 of the ice maker storage unit 12 is filled with ice, alternately performs an ice-making operation in ice-making mode, which involves cooling the refrigeration unit 30 to freeze the ice-making water in the cooled ice-making unit 21 to produce ice, and a de-icing operation after the ice-making operation, which involves heating the refrigeration unit 30 to separate the ice from the heated ice-making unit 21, thereby producing ice to be stored in the ice storage chamber 14 of the ice maker storage unit 12. When the ice storage detector 42 detects that the ice storage chamber 14 of the ice maker storage unit 12 is filled with ice, the ice maker 10 is controlled to enter standby mode and does not perform ice-making or de-icing operations, remaining in standby mode without producing ice to be stored in the ice storage chamber 14 of the ice maker storage unit 12.
[0037] This ice maker 10 is capable of performing a cooling operation in standby mode, which cools the ice making unit 21 by running a cooling operation on the refrigeration unit 30 to cool the ice making unit 21, thereby cooling the inside of the ice making and storage unit 12. The system is also controlled to temporarily enable heating operation when the refrigeration unit 30 is running a cooling operation in standby mode. Even if the cooling operation is started under conditions of low ambient temperature or when the temperature inside the ice making and storage unit 12 is low, the system controls the system to temporarily enable heating operation when the refrigeration unit 30 is running a cooling operation. This prevents the ice making and storage unit 12 from being overcooled without having to start and stop the compressor 31 of the refrigeration unit 30 for a short time, thus reducing the likelihood of arching, a problem caused by overcooling inside the ice making and storage unit 12 where multiple ice cubes fuse together.
[0038] The ice maker 10 in this embodiment is a so-called closed-cell type ice maker, but is not limited to this. The invention can also be applied to other ice makers, such as so-called open-cell type ice makers or vertical type ice makers that flow ice-making water down into a horizontally opening ice-making compartment, as long as the ice maker controls itself to perform ice-making operation in ice-making mode when the ice storage detector 42 does not detect that the ice storage compartment 14 is full of ice, and does not perform ice-making operation in standby mode when the ice storage detector 42 detects that the ice storage compartment 14 is full of ice. In this embodiment of the ice maker 10, the ice-making storage compartment 12 is partitioned by a drain pan 15 to allow ice and cold air to pass between the ice-making compartment 13 and the ice storage compartment 14, but is not limited to this, and may not be partitioned by a drain pan 15. Furthermore, the descriptions of temperature and time in this embodiment are examples, and the present invention is not limited to these descriptions of temperature and time. [Explanation of Symbols]
[0039] 10...Ice maker, 12...Ice storage unit, 21...Ice making section, 30...Refrigeration system, 31...Compressor, 34...Evaporator, 42...Ice storage detector.
Claims
[Claim 1] The ice-making section freezes ice-making water to produce ice, A refrigeration system capable of performing a cooling operation in which a refrigerant, which is pumped from a compressor and condensed in a condenser, is evaporated in an evaporator installed in the ice-making section to cool the ice-making section, and a heating operation in which hot gas refrigerant is sent from the compressor to the evaporator to heat the ice-making section, An ice-making storage cabinet is provided, in which the ice-making unit is located at the top and a space is formed in which ice produced by the ice-making unit can be stored. The system includes an ice storage detector that detects when the ice storage compartment is filled with ice, When the ice storage detector does not detect that the ice-making storage compartment is filled with ice, the system alternately performs an ice-making operation, in which the refrigeration device is cooled to produce ice by freezing the ice-making water in the cooled ice-making section, and a de-icing operation, in which the refrigeration device is heated after the ice-making operation to separate the ice from the heated ice-making section, thereby producing ice to be stored in the ice-making storage compartment. When the ice storage detector detects that the ice-making and ice storage compartment is filled with ice, the system is controlled to enter standby mode, and the ice-making and de-icing operations are not performed, so that it does not produce ice to be stored in the ice-making and ice storage compartment. An ice maker capable of performing a cooling operation to cool the ice-making section by running the refrigeration device during the standby mode, thereby enabling a cooling operation to be performed to cool the inside of the ice-making storage compartment, An ice maker characterized in that, while the cooling operation of the refrigeration device is being performed by the cooling operation during the standby mode, the heating operation is temporarily controlled to be able to be performed.