Ice maker

Abstract

To provide an ice making machine which properly performs an ice removal operation according to an outside atmospheric temperature.SOLUTION: An ice making machine 10 comprises: an ice making part 11 for making ice; an ice removal part 60 for removing ice from the ice making part 11 by imparting a calorie to the ice making part 11; an outside atmospheric temperature sensor (atmospheric temperature detection part) 58 for detecting an outside atmospheric temperature of the ice making part 11; and a control part for controlling the ice removal operation of the ice removal part 60, being a control part for controlling the ice removal operation of the ice removal part 60 so that the calorie imparted to the ice making part 11 is reduced by a comparison of the case that the atmospheric temperature is lower than a threshold when the atmospheric temperature detected by the outside atmospheric temperature sensor 58 is higher than the threshold.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The technology disclosed in this specification relates to an ice maker. [Background technology]

[0002] Conventionally, an ice-making machine is known, for example, as described in Patent Document 1. The ice-making machine described in Patent Document 1 includes an overflow section that discharges ice-making water above a predetermined water level from an ice-making water tank, and a water level detection means that detects the lower limit water level of the ice-making water stored in the ice-making water tank. The ice-making machine also includes a supply stop means that stops the supply of ice-making water when a specified amount of ice-making water is stored in the ice-making water tank during deicing operation. The ice-making machine also includes a prior drive means that drives the circulation pump under the condition that a predetermined time has passed since the water supply was stopped during deicing operation. The ice-making machine also includes a flocculation ice prevention means that temporarily stops the circulation pump based on the outlet temperature of the evaporator during ice-making operation. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5448618 Summary of the Invention [Problem to be solved by the invention]

[0004] In the deicing operation of the ice-making machine described in the above-mentioned Patent Document 1, the water supply valve is opened to spray deicing water from the deicing water sprinkler to the ice-making unit, and the hot gas valve is opened to supply hot gas from the compressor to the evaporator. Here, the temperature of the deicing water and the temperature of the hot gas can vary depending on the air temperature outside the ice-making unit. For this reason, if the deicing operation is performed based on a high air temperature, there is a problem that the amount of heat given to the ice at low temperatures is insufficient, resulting in incomplete deicing. Conversely, if the deicing operation is performed based on a low air temperature, there is a problem that the amount of heat given to the ice at high temperatures is excessive, causing the ice to melt more than necessary, resulting in a deterioration in energy-saving performance.

[0005] The technology described in this specification was developed based on the above circumstances, and has an object to perform appropriate deicing operation according to the outside air temperature. [Means for solving the problem]

[0006] (1) An ice making machine related to the technology described in this specification includes an ice making unit that produces ice, a de-icing unit that removes the ice from the ice making unit by applying heat to the ice making unit, an air temperature detection unit that detects the air temperature outside the ice making unit, and a control unit that controls the de-icing operation of the de-icing unit so that, when the air temperature detected by the air temperature detection unit is higher than a threshold value, the amount of heat applied to the ice making unit is less than when the air temperature is lower than the threshold value.

[0007] In this way, when ice-making operation is performed, water is frozen in the ice-making unit to produce ice. When de-icing operation is performed, the de-icing unit applies heat to the ice-making unit, melting the surface of the ice and forming a water film between the ice-making unit and the ice, so that the ice can be easily removed from the ice-making unit. Here, the amount of heat applied to the ice-making unit by the de-icing unit can vary depending on the temperature outside the ice-making unit, and there is a tendency for a larger amount of heat to be applied to the ice-making unit at high temperatures than at low temperatures. In view of this, the control unit controls the de-icing operation of the de-icing unit depending on the temperature detected by the temperature detection unit. That is, when the temperature detected by the temperature detection unit is higher than the threshold value, the control unit controls the de-icing operation of the de-icing unit so that the amount of heat applied to the ice-making unit is smaller than when the temperature is lower than the threshold value, so that the application of heat to the ice-making unit, which tends to be excessive at high temperatures, is suppressed. This makes it less likely that ice will melt more than necessary, improving energy-saving performance. Conversely, when the temperature detected by the temperature detection unit is lower than the threshold, the control unit controls the de-icing operation of the de-icing unit so that more heat is applied to the ice-making unit compared to when the temperature is higher than the threshold, so that the amount of heat applied to the ice-making unit, which tends to be insufficient at low temperatures, is compensated for, increasing the reliability of ice removal. As a result, the de-icing operation can be performed appropriately regardless of the temperature.

[0008] (2) In addition to the above (1), the control unit may control the de-icing operation of the de-icing unit to temporarily suspend the application of heat to the ice-making unit when the air temperature detected by the air temperature detection unit is higher than the threshold. Generally, it is difficult to apply heat uniformly to the entire area of ​​the ice-making unit during de-icing operation, so heat is applied to parts of the ice-making unit in sequence according to the configuration of the de-icing unit, and ice attached to each part is de-iced in the order in which the heat is applied. For this reason, if the de-icing unit were to continuously apply heat, heat would continue to be applied to the ice attached to the part of the ice-making unit to which heat is applied first until it is completely de-iced, which could cause the ice to melt more than necessary and deteriorate the energy-saving performance. In this regard, when the temperature detected by the temperature detection unit is higher than the threshold value, the control unit controls the deicing operation of the deicing unit to temporarily suspend the application of heat to the ice-making unit. Therefore, if a sufficient amount of heat is applied to the part of the ice-making unit to which heat is applied first during the period from when the deicing operation is started to when it is temporarily suspended, the surface of the ice attached to that part can be melted and de-iced while the deicing operation is temporarily suspended. This makes it less likely that the ice that is de-iced first will melt more than necessary. When the deicing operation is resumed, heat is applied to the remaining part of the ice-making unit, and the remaining ice attached to that part can be de-iced. As described above, the application of heat is performed efficiently, which is suitable for improving energy-saving performance.

[0009] (3) In addition to the above (2), the control unit may control the de-icing operation of the de-icing unit so that the time during which the de-icing operation is temporarily stopped is longer than the time from when the application of heat to the ice-making unit is started to be paused. In this way, the time during which the de-icing operation is temporarily stopped is sufficiently secured, so that the surface of the ice that has adhered to the part of the ice-making unit to which heat is applied first can be sufficiently melted during the temporary stop period, and the certainty that the ice will be de-iced is increased. Therefore, the heat applied after the application of heat to the ice-making unit is resumed is highly likely to be used to de-ice the ice that has adhered to the remaining part of the ice-making unit. This increases the certainty that the application of heat is performed efficiently, which is more suitable for improving energy-saving performance.

[0010] (4) In addition to any one of (1) to (3), the ice-making machine includes a compressor for compressing a refrigerant, a condenser for cooling and condensing the refrigerant from the compressor, an evaporator arranged in the ice-making unit for evaporating the refrigerant from the condenser to cool the ice-making unit, and a hot gas supply unit for supplying the refrigerant from the compressor as hot gas to the evaporator, the hot gas supply unit constituting the de-icing unit, and the control unit may control the de-icing operation of the hot gas supply unit so that the amount of hot gas supplied by the hot gas supply unit is reduced when the air temperature detected by the air temperature detection unit is higher than the threshold value, compared to when the air temperature is lower than the threshold value. In this way, the refrigerant compressed by the compressor is cooled and condensed in the condenser, and then evaporated in the evaporator to remove heat from the ice-making unit and cool the ice-making unit. As a result, ice is produced in the ice-making unit. When the de-icing operation is performed, the hot gas supply unit supplies the refrigerant from the compressor to the evaporator as hot gas, which imparts heat to the ice making unit, and the heat melts the surface of the ice to remove the ice. The temperature of this hot gas tends to change depending on the air temperature outside the ice making unit. In response to this, when the air temperature detected by the air temperature detection unit is higher than a threshold, the control unit controls the de-icing operation of the hot gas supply unit so that the amount of hot gas supplied is reduced compared to when the air temperature is lower than the threshold. Therefore, even if the temperature of the hot gas tends to be high due to the air temperature outside, the impartment of heat to the ice making unit is suppressed. This makes it less likely that ice will melt more than necessary, improving energy-saving performance.

[0011] (5) In addition to the above (4), the ice-making machine may further include a hot gas supply unit having a hot gas supply pipe connected to the compressor and the evaporator, and a hot gas valve disposed in the hot gas supply pipe, and the control unit may control the deicing operation of the hot gas supply unit so that the opening time of the hot gas valve is shorter when the air temperature detected by the air temperature detection unit is higher than the threshold value, compared to when the air temperature is lower than the threshold value. In this way, the hot gas supply unit supplies the amount of hot gas according to the opening degree and opening time of the hot gas valve to the evaporator through the hot gas supply pipe. The control unit adjusts the amount of hot gas supply by adjusting the opening time of the hot gas valve according to the air temperature detected by the air temperature detection unit, so that the control unit can easily and reliably manage the amount of hot gas supply compared to when the control unit adjusts the opening degree of the hot gas valve to adjust the amount of hot gas supply.

[0012] (6) In addition to any one of (1) to (5), the ice making machine may further include a deicing water supply unit that supplies deicing water to the ice making unit, the deicing water supply unit constituting the deicing unit, and the control unit may control the deicing operation of the deicing water supply unit so that the amount of deicing water supplied by the deicing water supply unit is reduced when the air temperature detected by the air temperature detection unit is higher than the threshold value, compared to when the air temperature is lower than the threshold value. In this way, when the deicing operation is performed, the deicing water supply unit supplies deicing water to the ice making unit, thereby imparting heat to the ice making unit, and the heat melts the surface of the ice, causing it to be deiced. The temperature of the deicing water supplied by the deicing water supply unit tends to change depending on the air temperature outside the ice making unit. In response to this, when the air temperature detected by the air temperature detection unit is higher than the threshold, the control unit controls the deicing operation of the deicing water supply unit so that the amount of deicing water supplied by the deicing water supply unit is reduced compared to when the air temperature is lower than the threshold, so that even if the temperature of the deicing water tends to be high due to the outside air temperature, the amount of heat applied to the ice making unit is suppressed. This makes it less likely that ice will melt more than necessary, improving energy-saving performance.

[0013] (7) In addition to the above (6), the ice making machine may further include an ice making water supply unit that supplies ice making water to the ice making unit, the ice making unit includes an ice making plate having an ice making surface along which the ice making water supplied by the ice making water supply unit flows, and the de-icing water supply unit may supply the de-icing water to a surface of the ice making plate opposite to the ice making surface, so that the de-icing water flows down. In this way, when making ice, the ice making water supplied from the ice making water supply unit to the ice making unit flows down the ice making surface of the ice making plate, so that ice grows on the ice making surface. When de-icing, the de-icing water supplied from the ice making water supply unit to the ice making unit flows down the surface of the ice making plate opposite to the ice making surface, so that heat is applied to the ice making plate, and the surface of the ice attached to the ice making surface is melted by the heat, so that the ice is de-iced.

[0014] (8) In addition to the above (6) or (7), the ice making machine may further include a deicing water supply unit having a deicing water supply pipe connected to the deicing water supply source and the ice making unit, and a deicing water valve disposed in the deicing water supply pipe, and the control unit may control the deicing operation of the deicing water supply unit so that the opening time of the deicing water valve is shorter when the air temperature detected by the air temperature detection unit is higher than the threshold value, compared to when the air temperature is lower than the threshold value. In this way, the deicing water supply unit supplies the amount of deicing water according to the opening degree and opening time of the deicing water valve to the ice making unit through the deicing water supply pipe. The control unit adjusts the amount of deicing water supplied by adjusting the opening time of the deicing water valve according to the air temperature detected by the air temperature detection unit, so that the control unit can easily and reliably manage the amount of deicing water supplied, compared to when the control unit adjusts the amount of deicing water supplied by adjusting the opening degree of the deicing water valve.

[0015] (9) In addition to any one of (1) to (8), the ice-making machine may further include an alarm unit that issues an alarm, and the control unit may cause the alarm unit to issue the alarm when the temperature detected by the temperature detection unit is higher than the alarm reference temperature. In this way, when the temperature outside the ice-making unit rises abnormally and becomes higher than the alarm reference temperature, the control unit can cause the alarm unit to issue an alarm to prompt the user to take action. This makes it possible to avoid a situation in which an abnormal temperature rise continues and causes a breakdown or the like.

[0016] (10) In addition to any one of (1) to (9) above, the ice-making machine may be configured such that, when the air temperature detected by the air temperature detection unit is higher than the emergency stop reference temperature, the control unit emergency stops the operation of the ice-making unit and the de-icing unit. In this way, when the air temperature outside the ice-making unit rises abnormally and becomes higher than the emergency stop reference temperature, the control unit can suppress a further temperature rise by emergency stopping the operation of the ice-making unit and the de-icing unit. This makes it possible to avoid a situation in which a breakdown or the like occurs due to an abnormal rise in temperature.

[0017] (11) In addition to the above (9) or (10), the ice maker may further include a control unit having a control board on which electronic components are mounted, and the air temperature detection unit is mounted on the control board. Electronic components mounted on the control board are more susceptible to failure due to temperature rise than mechanical components. In contrast, by mounting the air temperature detection unit on the control board, the air temperature detection unit can detect the air temperature near the control board, and the control unit can cause the notification unit to issue a warning based on the air temperature near the control board, or can cause an emergency stop of the operation of the ice-making unit and the de-icing unit. This makes it less likely for electronic components to fail, and thus helps to preserve the control board.

[0018] (12) In addition to any one of (1) to (11), the ice-making unit may include a cooling unit that cools ice-making water to produce the ice, and a storage unit that houses the cooling unit, and the air temperature detection unit may be disposed outside the storage unit. In this manner, when making ice, the ice-making water is cooled by the cooling unit inside the storage unit to produce ice. Since the air temperature detection unit is disposed outside the storage unit that houses the cooling unit, it can properly detect the outside air temperature without being affected by the cooling associated with ice-making. Effect of the Invention

[0019] According to the technology described in this specification, deicing operation can be performed appropriately according to the outside air temperature. [Brief description of the drawings]

[0020] [Figure 1] Schematic diagram of an ice making machine according to embodiment 1 [Diagram 2] Enlarged side view of the ice making section [Diagram 3] Block diagram showing the electrical configuration of the ice maker [Figure 4] A flowchart showing the process of the control unit related to the deicing operation. [Diagram 5] Schematic diagram of an ice maker according to embodiment 2 [Figure 6] Block diagram showing the electrical configuration of the ice maker [Figure 7] A flowchart showing the process of the control unit related to the deicing operation. [Figure 8] Schematic diagram of an ice making machine according to embodiment 3 [Figure 9] Block diagram showing the electrical configuration of the ice maker DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] <Embodiment 1> A first embodiment will be described with reference to Figures 1 to 4. In this embodiment, a flow-down type ice-making machine 10 is exemplified as the ice-making machine.

[0022] As shown in FIG. 1, ice making machine 10 comprises ice making section 11 which generates (manufactures) ice I by freezing water, a cooling device 40 for cooling ice making section 11 (more specifically, each ice making plate 12 provided in ice making section 11), a water tank 13 for storing water to be supplied to ice making section 11, an ice storage compartment 14 for storing ice produced by ice making section 11, and a circulation pump 15 capable of circulating water between ice making section 11 and water tank 13. Ice maker 10 also includes a first water pipe (ice-making water supply pipe) 18 that connects ice-making section 11 and circulation pump 15, a drain pipe 20 that is pulled out from an intermediate section 19 of first water pipe 18 and is used to drain water from water tank 13 to the outside, a drain valve 21 that opens and closes drain pipe 20, a water supply pipe (de-icing water supply pipe) 29 that is connected to a water pipe (de-icing water supply source) 31, a water supply valve (de-icing water valve) 30 that opens and closes water supply pipe 29, a second water pipe 32 that connects drain pipe 20 and water supply pipe 29, and a cleaning valve 34 that opens and closes second water pipe 32.

[0023] As shown in Fig. 1, the cooling device 40 includes a compressor 41, a condenser 42, an expansion valve (capillary tube) 43, and an evaporation pipe (evaporator) 44, which are connected by a refrigerant pipe 45 to form a known vapor compression refrigeration circuit (refrigeration cycle). The cooling device 40 also includes a fan (condenser fan, cooling fan) 46 for air-cooling the condenser 42, and a dryer 47 for removing moisture mixed into the refrigeration circuit. The evaporation pipe 44 is brazed and arranged in a serpentine shape between a plurality of ice-making plates (cooling sections) 12, and cools the ice-making plates 12 by vaporizing (evaporating) the liquid refrigerant expanded by the expansion valve 43. An ice-making section temperature sensor 16 (e.g., a thermistor) for detecting the temperature of the ice-making plates 12 is provided near the outlet of the evaporation pipe 44 in the refrigerant pipe 45.

[0024] The cooling device 40 includes a bypass pipe (a part of a hot gas supply pipe) 49, one end of which is connected to the compressor 41, and a hot gas valve 50, which is an electromagnetic valve connected to the other end of the bypass pipe 49. A common refrigerant pipe (a part of a hot gas supply pipe) 45A, which is a part of the refrigerant pipe 45, is connected to the hot gas valve 50. The common refrigerant pipe 45A has a branch structure at one end, one branch part at the one end is connected to the hot gas valve 50, the other branch part is connected to the expansion valve 43, and the other end is connected to the evaporation pipe 44. With the above configuration, when the hot gas valve 50 is opened, hot gas, which is a refrigerant gas compressed by the compressor 41, is supplied to the evaporation pipe 44 via the bypass pipe 49, the hot gas valve 50, and the common refrigerant pipe 45A. The common refrigerant pipe 45A, the bypass pipe 49, and the hot gas valve 50 constitute a hot gas supply unit 57 that supplies hot gas for heating (deicing) to the evaporation pipe 44. The common refrigerant pipe 45A, together with the expansion valve 43, constitutes a refrigerant supply unit that supplies the refrigerant to the evaporation pipe 44 for cooling.

[0025] As shown in Fig. 1, ice making section 11 includes ice making plate 12, a first sprinkler pipe 24 and a sprinkler guide 25 for sprinkling water for making ice (ice making water) onto ice making plate 12, a second sprinkler pipe 23 capable of sprinkling water (deicing water) for melting generated ice I, and a storage section 22 for storing these components 12, 23, 24, and 25. Ice making plate 12 is stored in storage section 22 with its plate surface hanging down. Ice making plate 12 is made up of two plates arranged with one plate surface facing each other to form one set, and multiple sets (three sets in Fig. 1) are arranged side by side at intervals along the normal direction of the plate surfaces of ice making plate 12. Of the pair of plate surfaces in each of the two ice-making plates 12 that make up a set, the plate surfaces that are back-to-back (non-facing) are each designated as ice-making surfaces 12A, and each ice-making surface 12A (ice-making space) is separated by a partition portion 12B extending in the vertical direction.

[0026] The first sprinkler pipe 24 and the sprinkler guide 25 are provided on the upper side of the ice making plate 12, as shown in Figures 1 and 2. The water (ice making water) sent to the first sprinkler pipe 24 through the first water passage pipe 18 by the circulation pump 15 is sprinkled from the first sprinkler pipe 24 and guided by the sprinkler guide 25 toward each ice making surface 12A, so that the water flows down each ice making surface 12A while being uniformly sprinkled onto each ice making surface 12A. In this way, the circulation pump 15, the first water passage pipe 18, and the first sprinkler pipe 24 constitute an ice making water supply section 36 that supplies the ice making water to the ice making section 11 for making ice I in the ice making section 11.

[0027] As shown in Fig. 2, the second sprinkling pipe 23 is provided at the upper part between the two ice-making plates 12 that form one set, and is connected to a water pipe 31, which is a tap water supply source, via a water supply pipe 29 and a water supply valve 30. By opening the water supply valve 30, water (de-icing water) is sprinkled from the second sprinkling pipe 23, and the sprinkled water flows down the back surface (opposite surface, the surface opposite to ice-making surface 12A) of the ice-making plate 12 and is supplied to the water tank 13. The second sprinkling pipe 23 has a function of warming the ice-making plate 12 by imparting heat with tap water, and a water supply function of supplying tap water to the water tank 13. When ice I is attached to ice-making surface 12A of ice-making plate 12 and de-icing water is supplied from second water sprinkler pipe 23 to the back surface of ice-making plate 12, heat is applied to ice-making plate 12, causing the surface of ice I to melt and a water film to form, resulting in ice I being removed from ice-making surface 12A. In this way, second water sprinkler pipe 23, water supply pipe 29 and water supply valve 30 constitute de-icing water supply section 37 that supplies de-icing water to ice-making section 11 to remove ice I from ice-making section 11.

[0028] As shown in FIG. 1, the evaporator tube 44 is arranged between two ice-making plates 12 that constitute one set. In detail, the evaporator tube 44 extends horizontally in the space between the two ice-making plates 12 that constitute one set, turns downward near the end of the ice-making plate 12, and extends horizontally again, repeating this process, so that the evaporator tube 44 is arranged in a serpentine shape that progresses stepwise downward. Therefore, in a cross section of the horizontal center part of the ice-making plate 12, a plurality of parts of the evaporator tube 44 that extend horizontally are arranged at intervals in the vertical direction. The upper end of the evaporator tube 44 is an inlet end that is drawn out of the space between the two ice-making plates 12 and connected to an end of the common refrigerant tube 45A, while the lower end is an outlet end that is drawn out of the space between the two ice-making plates 12 and connected to the other end of the refrigerant tube 45, one end of which is connected to the input side of the compressor 41. Therefore, the refrigerant and hot gas supplied from the common refrigerant pipe 45A to the evaporation pipe 44 flows from the inlet end to the outlet end of the evaporation pipe 44, so that the upper portion of the ice-making plate 12 is cooled or heated before the lower portion. When the expansion valve 43 is opened, the refrigerant expanded by the expansion valve 43 is supplied to the evaporation pipe 44 by the common refrigerant pipe 45A, and the refrigerant is vaporized (evaporated), so that heat can be taken from the ice-making plate 12, thereby cooling the ice-making plate 12. On the other hand, when the hot gas valve 50 is opened, the hot gas compressed by the compressor 41 is supplied to the evaporation pipe 44 by the common refrigerant pipe 45A, so that heat can be imparted to the ice-making plate 12, thereby heating the ice-making plate 12.

[0029] More specifically, the serpentine evaporator tube 44 is brazed to the back surfaces of the two ice-making plates 12 as shown in Fig. 2. Therefore, when the expansion valve 43 is opened and a refrigerant for cooling is supplied to the evaporator tube 44, ice I having a generally crescent-shaped cross section is generated on the ice-making surface 12A, centered on the part of the ice-making plate 12 that is in contact with the evaporator tube 44. On the other hand, when the hot gas valve 50 is opened and hot gas for heating is supplied to the evaporator tube 44, heat is applied from the evaporator tube 44 to the part of the ice-making plate 12 that is in contact with the evaporator tube 44, so that the surface of the ice I melts centered on the thickest part. In addition, when the water supply valve 30 is opened and the deicing water from the second watering pipe 23 is supplied to the rear surface of the ice making plate 12, the deicing water is sprayed on the portion of the rear surface of the ice making plate 12 that is not in contact with the evaporator tube 44 (non-contact portion) and heat is applied to that portion, so that the surface of the ice I is melted mainly around the both end portions sandwiching the thickest portion of the ice. The deicing water supplied to the rear surface of the ice making plate 12 is also sprayed on the evaporator tube 44. Here, if the opening of the water supply valve 30 is synchronized with the opening of the hot gas valve 50, the deicing water sprayed on the evaporator tube 44 is given heat from the evaporator tube 44, so that the temperature of the deicing water is increased. The deicing water with an increased temperature is sprayed on the rear surface of the ice making plate 12, so that the melting of the ice I is promoted. As described above, when heat is applied to the ice making plate 12, the surface of the ice I is melted and a water film is generated, and as a result, the ice I is deiced from the ice making surface 12A. It can be said that the deicing water supply unit 37 that supplies deicing water and the hot gas supply unit 57 that supplies hot gas each constitute a deicing unit 60 that removes the ice I from the ice-making unit 11.

[0030] As shown in Fig. 1, water tank 13 is disposed below ice-making plate 12, and unfrozen ice that flows down ice-making plate 12 is stored in water tank 13. This allows water to circulate between water tank 13 and ice-making unit 11 by operating circulation pump 15. Water tank 13 and ice-making unit 11 are included on two water flow paths (first water flow path, second water flow path), and circulation pump 15 can circulate water in each water flow path. The first water flow path is a path that passes from the water tank 13 through the circulation pump 15, the first water pipe 18, the first water sprinkler pipe 24, and the ice-making surface 12A of the ice-making plate 12, and returns to the water tank 13. The second water flow path is a path that passes from the water tank 13 through the circulation pump 15, the first water pipe 18, the drain pipe 20, the second water pipe 32, the water supply pipe 29, the second water sprinkler pipe 23, and the back surface of the ice-making plate 12, and returns to the water tank 13. The first water flow path and the second water flow path can be switched by opening and closing the cleaning valve 34. For example, if clean water or washing water containing detergent is placed in the water tank 13 in advance and the circulation pump 15 is operated with the drain valve 21, the water supply valve 30, and the cleaning valve 34 all closed, the clean water or washing water will flow through the first water flow path and can wash the ice-making surface 12A side of the ice-making plate 12. In addition, if clean water or cleaning water containing detergent is placed in the water tank 13 in advance, and the circulation pump 15 is operated with the drain valve 21 and the water supply valve 30 closed and the cleaning valve 34 open, the clean water or cleaning water will flow through the second water flow path and clean the back side of the ice making plate 12 (including the evaporator tube 44).

[0031] Furthermore, the first water pipe 18 extends upward from the water tank 13 and the circulation pump 15, and a drain pipe 20 is provided at its middle portion 19 for draining the water in the water tank 13 to the outside. This drain pipe 20 is provided with a drain valve 21 that opens and closes the drain pipe 20. As a result, when the circulation pump 15 is operated with the drain valve 21 open, the water in the water tank 13 can be drained through the drain pipe 20. In this way, the circulation pump 15, the first water pipe 18, and the drain pipe 20 form a drainage path.

[0032] 1, the water tank 13 includes a box-shaped tank body 26 having an opening at the top, and a lid 27 that partially covers the opening at the top of the tank body 26. The portion of the tank body 26 that is not covered by the lid 27 is disposed at a position where water falls from the ice-making plate 12, and a cube guide 28 is interposed between this portion and the ice-making plate 12. The cube guide 28 is a grate-like member with a plurality of through holes formed therein, and the water that flows down from the ice-making plate 12 passes through the cube guide 28 and is collected in the water tank 13. Meanwhile, the ice that falls from the ice-making plate 12 slides down the cube guide 28 and is thrown into the ice storage 14.

[0033] As shown in Fig. 1, the lid 27 is fixed with a water level sensor 17 for detecting the water level in the circulation pump 15 and the tank main body 26. The circulation pump 15 has a motor with a variable rotation speed as a power source, and the water is circulated by driving the motor, and the amount of water circulated can be changed by the rotation speed of the motor. The water level sensor 17 is a float switch equipped with a float (float 17A). When the float 17A is displaced up and down by buoyancy according to the water level in the tank main body 26, a reed switch included in the main body of the water level sensor 17 is turned on and off by the displacement. The water level sensor 17 is capable of detecting two predetermined water levels (lower reference water level L1, upper reference water level L2) by two reed switches.

[0034] As shown in FIG. 1, the tank body 26 is configured to be able to drain water that exceeds a predetermined overflow level L3 to the outside of the water tank 13 when the water in the tank body 26 exceeds the predetermined overflow level L3. More specifically, the tank body 26 is provided with an overflow space A2 adjacent to the water storage space A1 in which water is stored. The overflow space A2 has a function of draining water that overflows from the water storage space A1. The tank body 26 is provided with a vertical wall portion 35 as an overflow barrier that determines the overflow level L3, and when the water level in the water storage space A1 exceeds the overflow barrier (overflow level L3), the water flows into the overflow space A2 and is drained. The upper reference water level L2 that can be detected by the water level sensor 17 is set to a value smaller than the overflow water level L3, and the relationship is L3>L2>L1.

[0035] As shown in FIG. 1, ice storage bin 14 is provided below water tank 13 so that ice that slides down cube guide 28 falls and is stored therein. Ice storage bin 14 is connected to the lower part (ice discharge side end) of ice-making section 11 via ice discharge pipe 51. Ice discharge pipe 51 has an upper end connected to the lower part of storage section 22 constituting ice-making section 11, and a lower end connected to opening 14A formed at the upper part of ice storage bin 14. Cube guide 28 described above forms a part of ice discharge pipe 51. Ice that falls into ice storage bin 14 is stored by piling up from bottom part 14B of ice storage bin 14. An ice storage sensor 33 is provided at the upper part of ice storage bin 14 to detect the amount of ice I stored in ice storage bin 14. Ice storage sensor 33 is an ice storage switch equipped with a flap plate 33A, and when ice piles up in ice storage 14 and becomes full (an example of an upper limit amount), flap plate 33A is pushed upward by ice I and full ice is detected.

[0036] Next, the electrical configuration of ice-making machine 10 will be described. Ice-making machine 10 includes control unit 80 as shown in FIG. 3. Cooling device 40 (more specifically, compressor 41, expansion valve 43, fan 46, and hot gas valve 50), circulation pump 15, ice-making unit temperature sensor 16, water level sensor 17, water supply valve 30, drain valve 21, cleaning valve 34, timing unit 53 (timer), and memory unit 54 are electrically connected to control unit 80. Ice-making machine 10 also includes operation unit 55 consisting of switches that can be operated by the user, and display unit 56 (e.g., a liquid crystal panel) that can display warning images such as error messages. In other words, display unit 56 is a notification unit that can notify the user of warnings. Operation unit 55 and display unit 56 are each electrically connected to control unit 80.

[0037] Control unit 80 is mainly composed of, for example, a CPU, and memory unit 54 is composed of, for example, a ROM, a RAM, etc. Control unit 80 executes a program stored in memory unit 54, thereby being able to control the operation of each device (cooling device 40, circulation pump 15, water supply valve 30, drain valve 21, cleaning valve 34, display unit 56, etc.) based on the operation of operation unit 55 by the user, the measured values ​​of each sensor (ice-making unit temperature sensor 16, water level sensor 17, etc.), and the time measurement by timer unit 53. Also, memory unit 54 stores various setting values ​​related to the operation of ice maker 10. Also, control unit 80 is able to refer to the rotation speed and current value of the pump motor provided in circulation pump 15.

[0038] The control unit 80 is capable of performing ice making operation, deicing operation, and cleaning operation. The ice making operation is an operation in which the cooling device 40 is operated to cool the ice making plate 12 while the circulation pump 15 is operated to produce ice I in the ice making unit 11. The deicing operation is an operation in which the deicing water supply unit 37 and the hot gas supply unit 57 constituting the deicing unit 60 supply deicing water to the ice making plate 12 and supply hot gas to the evaporation tube 44 to impart heat to the ice making plate 12, and the produced ice I is removed from the ice making surface 12A of the ice making unit 11. Specifically, during the deicing operation, the circulation pump 15, the water supply valve 30, and the hot gas valve 50 are operated while the cooling device 40 is operated. The cleaning operation is an operation in which the circulation pump 15 is operated with the cooling device 40 stopped to circulate water between the water tank 13 and the ice making unit 11, and the ice making water flow path (circulation path) is cleaned.

[0039] The control unit 80 as described above includes a control board 81 on which various electronic components are mounted, as shown in FIG. 1. The control board 81 is housed in a control box 82 disposed above the condenser 42. The control board 81 is equipped with a memory unit 54 (see FIG. 3). The control board 81 is equipped with an outside air temperature sensor (air temperature detection unit) 58 for detecting the air temperature (outside air temperature) outside the ice-making unit 11. The outside air temperature sensor 58 is made of, for example, a thermistor, and is capable of detecting the air temperature near the control board 81 (inside the control box 82). The control box 82 in which the outside air temperature sensor 58 is housed is located at a sufficient distance from the accommodation unit 22 of the ice-making unit 11, so that the temperature environment inside the control box 82 is hardly affected by the cooling or heating associated with the ice-making and de-icing performed in the ice-making unit 11. Therefore, the outside air temperature sensor 58 can appropriately detect the air temperature outside the accommodation unit 22 of the ice-making unit 11.

[0040] Incidentally, the amount of heat imparted to the ice-making unit 11 by the deicing unit 60 during the deicing operation can vary depending on the temperature outside the ice-making unit 11. For example, in an environment where the outside temperature is high, such as in summer, the temperature of the deicing water supplied to the ice-making plate 12 by the deicing water supply unit 37 constituting the deicing unit 60 during the deicing operation tends to be high, so the amount of heat imparted to the ice-making plate 12 by the deicing water tends to be excessive. Conversely, in an environment where the outside temperature is low, such as in winter, the temperature of the deicing water supplied to the ice-making plate 12 by the deicing water supply unit 37 constituting the deicing unit 60 during the deicing operation tends to be low, so the amount of heat imparted to the ice-making plate 12 by the deicing water tends to be insufficient. For example, if the amount of deicing water supplied during deicing operation is set with a priority on increasing the reliability of deicing ice I from ice-making plates 12 in an environment with a low outside air temperature, the amount of deicing water supplied during deicing operation will be excessive in an environment with a high outside air temperature, and the amount of heat applied to ice-making plates 12 will be excessive. This may result in more ice I melting than necessary, resulting in a significant decrease in energy-saving performance.

[0041] In view of such problems, the control unit 80 according to the present embodiment controls the deicing operation of the deicing water supply unit 37 constituting the deicing unit 60 in accordance with the air temperature detected by the outside air temperature sensor 58, as shown in FIG. 3. That is, when the air temperature detected by the outside air temperature sensor 58 is higher than the threshold TH1, the control unit 80 controls the deicing operation of the deicing water supply unit 37 so that the amount of deicing water supplied to the ice making unit 11 by the deicing water supply unit 37 is reduced and the amount of heat imparted to the ice making unit 11 is reduced, compared to when the air temperature is lower than the threshold TH1. The threshold TH1, which is the reference when the control unit 80 changes the deicing operation, is stored in the memory unit 54, and the control unit 80 appropriately refers to the threshold TH1 in the memory unit 54. The outside air temperature sensor 58 can directly input a signal related to the detected air temperature to the control unit 80, but it can also be stored in the memory unit 54.

[0042] In this way, when the air temperature detected by the outside air temperature sensor 58 is higher than the threshold TH1, the deicing operation of the deicing water supply unit 37 constituting the deicing unit 60 is controlled by the control unit 80 so that the amount of deicing water supplied to the ice making unit 11 is less than when the air temperature is lower than the threshold TH1. Therefore, even if the temperature of the deicing water tends to be high due to the high outside air temperature, the amount of heat supplied to the ice making unit 11, which tends to be excessive, is suppressed. This makes it difficult for the ice I to melt more than necessary, improving energy saving performance. On the other hand, when the air temperature detected by the outside air temperature sensor 58 is lower than the threshold TH1, the deicing operation of the deicing water supply unit 37 constituting the deicing unit 60 is controlled by the control unit 80 so that the amount of deicing water supplied to the ice making unit 11 is more than when the air temperature is higher than the threshold TH1. Therefore, even if the temperature of the deicing water tends to be low due to the low outside air temperature, the amount of heat supplied to the ice making unit 11, which tends to be insufficient, is compensated for, and the reliability of deicing is increased. As a result, deicing operation can be performed appropriately regardless of the temperature outside.

[0043] Furthermore, when the air temperature detected by the outside air temperature sensor 58 is higher than the threshold TH1, the control unit 80 controls the deicing operation of the deicing water supply unit 37 so that the opening time of the water supply valve 30 is shorter than when the air temperature is lower than the threshold TH1. The control unit 80 controls the opening degree of the water supply valve 30 to be approximately constant while adjusting the opening time of the water supply valve 30. The deicing water supply unit 37 supplies the amount of deicing water according to the opening degree and opening time of the water supply valve 30 to the ice making unit 11 through the water supply pipe 29. Here, if the opening degree of the water supply valve 30 is adjusted by the control unit when adjusting the supply amount of deicing water, it becomes difficult to appropriately manage the supply amount of deicing water, and there is a risk that the reliability of achieving the target supply amount is reduced. In this regard, the control unit 80 adjusts the supply amount of deicing water by adjusting the opening time of the water supply valve 30 according to the air temperature detected by the outside air temperature sensor 58, so that the management of the supply amount of deicing water can be easily and reliably performed.

[0044] Next, specific processing of the control unit 80 during deicing operation will be described. During deicing operation, as shown in Fig. 4, the control unit 80 performs a drainage operation (drainage process) in which the water in the water tank 13 is drained to the outside through the drain pipe 20 by operating the circulation pump 15 with the drain valve 21 open (step S11). As the water level in the water tank 13 decreases with the drainage, and when the water level detected by the water level sensor 17 falls below the lower reference water level L1, the control unit 80 determines that drainage is complete, stops the circulation pump 15, and closes the drain valve 21 to stop the drainage operation.

[0045] In addition, in the ice-making operation of the flow-down type ice maker, impurities contained in the water in the water tank 13 are difficult to freeze on the ice-making surface 12A and are collected in the water tank 13, so that the ice I has an extremely low impurity content (ultrapure water). In other words, immediately after the completion of the ice-making operation, the water in the water tank 13 is concentrated water with a high concentration of impurities. Such concentrated water causes scale to form in the flow water path. For this reason, it is more preferable to perform a drainage operation immediately after the ice-making operation to drain the concentrated water. In addition, in the drainage operation, the control unit 80 controls the rotation speed of the circulation pump 15 so that the height of the water pumped up by the circulation pump 15 is the height between the ice-making unit 11 and the intermediate unit 19. This makes it possible to prevent the water in the water tank 13 to be drained from moving toward the ice-making unit 11, and to more reliably drain the water.

[0046] Next, the control unit 80 stops the fan 46 and opens the hot gas valve 50 (step S12). This allows hot gas to be supplied from the compressor 41 through the common refrigerant pipe 45A to the evaporation tube 44, heating the evaporation tube 44. When the evaporation tube 44 is heated, heat is applied to the back side of the ice-making plate 12 that contacts the evaporation tube 44. At this time, the surface of the ice I, which has a roughly crescent-shaped cross section, melts around the thickest part.

[0047] Then, the control unit 80 acquires the temperature outside the ice making unit 11 detected by the outside air temperature sensor 58, and also acquires the threshold value TH1 by referring to the memory unit 54, and judges whether the temperature detected by the outside air temperature sensor 58 is higher than the threshold value TH1 (step S13). If the temperature detected by the outside air temperature sensor 58 is higher than the threshold value TH1 ("YES" in step S13), the control unit 80 opens the water supply valve 30 constituting the deicing water supply unit 37 (step S14). At this time, the control unit 80 opens the water supply valve 30 at a substantially constant opening. When the water supply valve 30 is opened, the deicing water is sprayed from the second water spray pipe 23 onto the back side of the ice making plate 12, and heat is applied. At this time, the surface of the ice I is melted mainly from both end side portions sandwiching the thickest part. In this way, the ice making plate 12 is heated by the deicing water and hot gas, and the surface of the ice I is melted to generate a water film, which promotes the deicing of the ice I from the ice making surface 12A.

[0048] Here, since the hot gas flows from the inlet end to the outlet end of the evaporator tube 44, the upper portion of the ice-making plate 12 is heated by the evaporator tube 44 before the lower portion. Similarly, since the deicing water flows down from the second watering pipe 23 arranged on the upper side of the ice-making plate 12, the upper portion of the ice-making plate 12 is heated by the deicing water before the lower portion. For this reason, if the deicing water supply unit continues to supply deicing water to the ice-making plate 12 and heat is continuously applied to the ice I attached to the upper portion of the ice-making plate 12 to which heat is applied first, heat continues to be applied to the ice I until the ice I is completely deiced. For this reason, the ice I attached to the upper portion of the ice-making plate 12 melts more than necessary, which may deteriorate the energy-saving performance.

[0049] In response to this, the control unit 80 judges whether the time that has elapsed since the water supply valve 30 was opened has passed a predetermined time T1 (e.g., 5 seconds) (step S15), and if so, closes the water supply valve 30 (step S16). Thereafter, the control unit 80 judges whether the time that has elapsed since the water supply valve 30 was closed has passed a predetermined time T2 (e.g., 10 seconds) (step S17), and if so, opens the water supply valve 30 again (step S18). At this time, the control unit 80 opens the water supply valve 30 at a substantially constant opening degree. In other words, when the temperature detected by the outside air temperature sensor 58 is higher than the threshold value TH1, the control unit 80 controls the deicing operation so as to temporarily halt the supply of deicing water by the deicing water supply unit 37. In this way, if a sufficient amount of heat is applied to the upper portion of the ice making plate 12 to which heat is applied first during the period from when the supply of deicing water by the deicing water supply unit 37 is started to when it is temporarily stopped (between steps S14 and S16), the surface of the ice I attached to the upper portion of the ice making plate 12 can be melted and de-iced during the period when the supply of deicing water by the deicing water supply unit 37 is temporarily stopped (between steps S16 and S18). As a result, the ice I that is to be de-iced first is not given more heat than necessary, and the ice I is less likely to melt more than necessary. In this way, when the supply of deicing water by the deicing water supply unit 37 is resumed (step S18) after waiting for the ice I that was attached to the upper portion of the ice making plate 12 during the temporary stop period to be de-iced, the heat from the deicing water is efficiently applied to the lower portion of the ice making unit 11 to which the remaining ice I is attached. As a result, the remaining ice can be efficiently de-iced. As described above, the amount of heat is efficiently applied to the ice making plate 12, which is preferable for improving energy saving performance.

[0050] Moreover, the control unit 80 controls the deicing operation so that the predetermined time T2 (e.g., 10 seconds) during which the deicing operation is paused is longer than the predetermined time T1 (e.g., 5 seconds) from when the water supply valve 30 is opened and the supply of deicing water to the ice-making plate 12 is started to be paused. In this way, the predetermined time T1 during which the supply of deicing water by the deicing water supply unit 37 is paused is sufficiently secured, so that the surface of the ice I attached to the upper part of the ice-making plate 12 to which heat is applied first can be sufficiently melted during the pause period, and the certainty that the ice I will be deiced is increased. Therefore, the certainty that the heat applied after the water supply valve 30 is opened again and the supply of deicing water to the ice-making plate 12 is resumed is used to de-ice the ice I attached to the lower part of the ice-making plate 12. This increases the certainty that the heat is efficiently applied to the ice-making plate 12, which is more suitable for improving energy-saving performance.

[0051] If the temperature detected by the outside air temperature sensor 58 is lower than the threshold value TH1 in step S13 ("NO" in step S13), the control unit 80 proceeds to step S18 and opens the water supply valve 30. At this time, the control unit 80 opens the water supply valve 30 at a substantially constant opening degree.

[0052] The ice I that has been removed from the ice-making surface 12A of the ice-making plate 12 as described above falls onto the cube guide 28 and is then stored in the ice storage 14. The de-icing water that has flowed down the back surface of the ice-making plate 12 falls into the water tank 13, causing the water level in the water tank 13 to rise. When the water level in the water tank 13 rises and eventually reaches an operation start water level that is lower than the overflow water level L3 ("YES" in step S19), the control unit 80 closes the water supply valve 30 to stop the water supply (step S20). When the ice I is removed, the melted water in which a part of the ice I (the part in contact with the ice-making surface 12A) has melted is collected in the water tank 13. Since this melted water contains few impurities, it is preferable to use it again for ice making without discharging it. For this reason, by stopping the water supply at an operation start water level that is lower than the overflow water level L3 as in steps S19 and S20, it is possible to prevent the melted water from overflowing and being discharged.

[0053] Thereafter, control unit 80 obtains the temperature detected by ice-making unit temperature sensor 16 and also references memory unit 54 to obtain a predetermined temperature C1 (e.g., 9°C) that serves as a criterion for judgment, and judges whether the temperature detected by ice-making unit temperature sensor 16 is higher than predetermined temperature C1 (step S21). If the temperature detected by ice-making unit temperature sensor 16 is higher than predetermined temperature C1 ("YES" in step S21), control unit 80 judges that all ice I on ice-making surface 12A has been removed, and stops the deicing operation. Then, it transitions to ice-making operation.

[0054] As described above, the ice making machine 10 of this embodiment comprises ice making unit 11 which produces ice, de-icing unit 60 which removes ice from ice making unit 11 by applying heat to ice making unit 11, outside air temperature sensor (air temperature detection unit) 58 which detects the air temperature outside of ice making unit 11, and control unit 80 which controls the de-icing operation of de-icing unit 60, such that when the air temperature detected by outside air temperature sensor 58 is higher than threshold value TH1, the control unit 80 controls the de-icing operation of de-icing unit 60 so that less heat is applied to ice making unit 11 compared to when the air temperature is lower than threshold value TH1.

[0055] In this way, when ice-making operation is performed, water is frozen in ice-making unit 11 to produce ice I. When deicing operation is performed, heat is applied to ice-making unit 11 by deicing unit 60, which melts the surface of ice I and creates a water film between ice-making unit 11 and the ice, so that ice can be easily removed from ice-making unit 11. Here, the amount of heat applied to ice-making unit 11 by deicing unit 60 can vary depending on the air temperature outside ice-making unit 11, and there is a tendency for more heat to be applied to ice-making unit 11 at high temperatures than at low temperatures. In view of this, control unit 80 controls the deicing operation of deicing unit 60 according to the air temperature detected by outside air temperature sensor 58. That is, when the air temperature detected by outside air temperature sensor 58 is higher than threshold value TH1, control unit 80 controls the deicing operation of deicing unit 60 so that less heat is applied to ice-making unit 11 compared to when the air temperature is lower than threshold value TH1, so that the application of heat to ice-making unit 11, which tends to be excessive at high temperatures, is suppressed. This makes it less likely that ice I will melt more than necessary, improving energy-saving performance. Conversely, when the air temperature detected by outside air temperature sensor 58 is lower than threshold TH1, control unit 80 controls the deicing operation of deicing unit 60 so that more heat is applied to ice-making unit 11 compared to when the air temperature is higher than threshold TH1, thereby compensating for the lack of heat applied to ice-making unit 11 at low temperatures and increasing the reliability of ice removal. As a result, deicing operation can be performed appropriately regardless of the temperature.

[0056] Furthermore, when the air temperature detected by the outside air temperature sensor 58 is higher than the threshold value TH1, the control unit 80 controls the deicing operation of the deicing unit 60 to temporarily suspend the application of heat to the ice-making unit 11. Generally, it is difficult to apply heat uniformly to the entire area of ​​the ice-making unit 11 during the deicing operation, so that heat is applied to parts of the ice-making unit 11 in sequence according to the configuration of the deicing unit 60, and the ice I attached to each part is deiced in the order in which the heat is applied. For this reason, if the deicing unit were to continuously apply heat, the ice I attached to the part of the ice-making unit 11 to which heat is applied first would continue to be applied until the ice I was completely deiced, and this would cause the ice I to melt more than necessary, which could deteriorate the energy-saving performance. In this regard, when the temperature detected by the outside air temperature sensor 58 is higher than the threshold value TH1, the control unit 80 controls the deicing operation of the deicing unit 60 to suspend the application of heat to the ice-making unit 11. Therefore, if a sufficient amount of heat is applied to the portion of the ice-making unit 11 to which heat is applied first during the period from when the deicing operation is started to when it is suspended, the surface of the ice I attached to that portion can be melted and deiced while the deicing operation is suspended. This makes it difficult for the ice I that is deiced first to melt more than necessary. When the deicing operation is resumed, heat is applied to the remaining portion of the ice-making unit 11, and the remaining ice attached to that portion can be deiced. As described above, the application of heat is performed efficiently, which is preferable for improving energy-saving performance.

[0057] Furthermore, control unit 80 controls the deicing operation of deicing unit 60 so that the time (second time) T2 during which the deicing operation is temporarily stopped is longer than the time (first time) T1 from when the application of heat to ice-making unit 11 is started to when the application of heat is temporarily stopped. In this way, the time T2 during which the deicing operation is temporarily stopped is sufficiently secured, so that the surface of ice I that has adhered to the portion of ice-making unit 11 to which heat is applied first can be sufficiently melted during the temporary stop period, and the certainty that the ice I will be deiced is increased. Therefore, the heat applied after the application of heat to ice-making unit 11 is resumed is highly likely to be used to de-ice the ice I that has adhered to the remaining portion of ice-making unit 11. This increases the certainty that the application of heat is performed efficiently, which is more suitable for improving energy-saving performance.

[0058] The ice making unit 11 further includes a deicing water supply unit 37 that supplies deicing water to the ice making unit 11. The deicing water supply unit 37 constitutes the deicing unit 60. When the air temperature detected by the outside air temperature sensor 58 is higher than the threshold TH1, the control unit 80 controls the deicing operation of the deicing water supply unit 37 so that the amount of deicing water supplied by the deicing water supply unit 37 is reduced compared to when the air temperature is lower than the threshold TH1. In this way, when the deicing operation is performed, the deicing water supply unit 37 supplies deicing water to the ice making unit 11, imparting heat to the ice making unit 11, and the surface of the ice I is melted by the heat, causing it to be deiced. The temperature of the deicing water supplied by the deicing water supply unit 37 tends to change depending on the air temperature outside the ice making unit 11. In response to this, when the air temperature detected by the outside air temperature sensor 58 is higher than the threshold TH1, the control unit 80 controls the deicing operation of the deicing water supply unit 37 so that the amount of deicing water supplied by the deicing water supply unit 37 is reduced compared to when the air temperature is lower than the threshold TH1, so that even if the temperature of the deicing water tends to be high due to the outside air temperature, the amount of heat imparted to the ice making unit 11 is suppressed. This makes it less likely that the ice I will melt more than necessary, improving energy saving performance.

[0059] The ice making unit 11 is also provided with an ice making water supply unit 36 ​​that supplies ice making water to the ice making unit 11. The ice making unit 11 is provided with an ice making plate 12 having an ice making surface 12A along which the ice making water supplied by the ice making water supply unit 36 ​​flows. The deicing water supply unit 37 supplies deicing water to the surface of the ice making plate 12 opposite to the ice making surface 12A and causes it to flow down. In this manner, during ice making, the ice making water supplied from the ice making water supply unit 36 ​​to the ice making unit 11 flows down the ice making surface 12A of the ice making plate 12, so that ice I grows on the ice making surface 12A. During deicing, the deicing water supplied from the deicing water supply unit 37 to the ice making unit 11 flows down the surface of the ice making plate 12 opposite to the ice making surface 12A, so that heat is imparted to the ice making plate 12, and the surface of the ice I attached to the ice making surface 12A is melted by the heat, and the ice I is deiced.

[0060] The deicing water supply unit 37 has a water supply pipe (deicing water supply pipe) 29 connected to the water pipe 31, which is a supply source of deicing water, and the ice making unit 11, and a water supply valve (deicing water valve) 30 disposed in the water supply pipe 29. When the air temperature detected by the outside air temperature sensor 58 is higher than the threshold TH1, the control unit 80 controls the deicing operation of the deicing water supply unit 37 so that the opening time of the water supply valve 30 is shorter than when the air temperature is lower than the threshold TH1. In this manner, the deicing water supply unit 37 supplies the amount of deicing water according to the opening degree and opening time of the water supply valve 30 to the ice making unit 11 through the water supply pipe 29. The control unit 80 adjusts the amount of deicing water supplied by adjusting the opening time of the water supply valve 30 according to the air temperature detected by the outside air temperature sensor 58. Therefore, the control unit 80 can easily and reliably manage the amount of deicing water supplied, compared to when the control unit adjusts the opening degree of the water supply valve 30 to adjust the amount of deicing water supplied.

[0061] Furthermore, ice-making unit 11 includes ice-making plate (cooling unit) 12 that cools ice-making water to produce ice, and storage unit 22 that houses ice-making plate 12, and outside air temperature sensor 58 is disposed outside storage unit 22. In this manner, when making ice, ice is produced by cooling the ice-making water inside storage unit 22 with ice-making plate 12. Because outside air temperature sensor 58 is disposed outside storage unit 22 that houses ice-making plate 12, it can properly detect the outside air temperature without being affected by the cooling that accompanies ice making.

[0062] <Embodiment 2> A second embodiment will be described with reference to Figures 5 to 7. In this second embodiment, the control of the deicing operation by the control unit 180 is changed. Note that a duplicated description of the structure, action, and effect similar to those of the first embodiment will be omitted. Also, components that appear in the description of this embodiment and have the same names as those in the first embodiment will be given the same reference numerals with the suffix "1" added to their beginning.

[0063] First, the amount of heat imparted to ice-making unit 111 by deicing unit 160 during deicing operation can vary depending on the temperature outside ice-making unit 111 (see FIG. 5). For example, in an environment with high outside air temperatures, such as in summer, the temperature of the hot gas supplied to evaporator tube 144 by hot gas supply unit 157 constituting deicing unit 160 during deicing operation tends to be high, so the amount of heat imparted to ice-making plate 112 by the hot gas tends to be excessive. Conversely, in an environment with low outside air temperatures, such as in winter, the temperature of the hot gas supplied to evaporator tube 144 by hot gas supply unit 157 constituting deicing unit 160 during deicing operation tends to be low, so the amount of heat imparted to ice-making plate 112 by the hot gas tends to be insufficient. For example, if the amount of hot gas supplied during deicing operation is set by prioritizing increasing the reliability of removing ice I from ice-making plates 112 in an environment with a low outside air temperature, the amount of hot gas supplied during deicing operation will be excessive in an environment with a high outside air temperature, and the amount of heat imparted to ice-making plates 112 will be excessive. This may result in more ice I melting than necessary, resulting in a significant decrease in energy-saving performance.

[0064] In consideration of such problems, the control unit 180 according to this embodiment controls the deicing operation of the hot gas supply unit 157 constituting the deicing unit 160 in accordance with the air temperature detected by the outside air temperature sensor 158, as shown in Figures 5 and 6. That is, when the air temperature detected by the outside air temperature sensor 158 is higher than threshold value TH1, the control unit 180 controls the deicing operation of the hot gas supply unit 157 so that the amount of hot gas supplied by the hot gas supply unit 157 is reduced and the amount of heat imparted to the ice making unit 111 is reduced, compared to when the air temperature is lower than threshold value TH1.

[0065] In this way, when the temperature detected by the outside air temperature sensor 158 is higher than the threshold TH1, the deicing operation of the hot gas supply unit 157 constituting the deicing unit 160 is controlled by the control unit 180 so that the amount of hot gas supplied to the evaporation tube 144 is less than when the temperature is lower than the threshold TH1. Therefore, even if the temperature of the hot gas tends to be high due to the high outside air temperature, the amount of heat supplied to the ice making unit 111, which tends to be excessive, is suppressed. This makes it difficult for the ice I to melt more than necessary, improving energy saving performance. On the other hand, when the temperature detected by the outside air temperature sensor 158 is lower than the threshold TH1, the deicing operation of the hot gas supply unit 157 constituting the deicing unit 160 is controlled by the control unit 180 so that the amount of hot gas supplied to the evaporation tube 144 is more than when the temperature is higher than the threshold TH1. Therefore, even if the temperature of the hot gas tends to be low due to the low outside air temperature, the amount of heat supplied to the ice making unit 111, which tends to be insufficient, is compensated for, and the reliability of ice removal is increased. As a result, deicing operation can be performed appropriately regardless of the temperature outside.

[0066] Furthermore, when the temperature detected by the outside air temperature sensor 158 is higher than the threshold TH1, the control unit 180 controls the deicing operation of the hot gas supply unit 157 so that the opening time of the hot gas valve 150 is shorter than when the temperature is lower than the threshold TH1. The control unit 180 controls the opening degree of the hot gas valve 150 to be approximately constant while adjusting the opening time of the hot gas valve 150. The hot gas supply unit 157 supplies the amount of hot gas according to the opening degree and opening time of the hot gas valve 150 to the evaporation tube 144 through the common refrigerant tube 145A. Here, if the opening degree of the hot gas valve 150 is adjusted by the control unit when adjusting the supply amount of hot gas, it becomes difficult to appropriately manage the supply amount of hot gas, and there is a possibility that the reliability of achieving the target supply amount is reduced. In this regard, the control unit 180 adjusts the amount of hot gas supplied by adjusting the opening time of the hot gas valve 150 in accordance with the air temperature detected by the outside air temperature sensor 158, so that management of the amount of hot gas supplied can be easily and reliably performed.

[0067] Next, specific processing of the control unit 180 during the deicing operation will be described. During the deicing operation, as shown in Fig. 7, the control unit 180 executes a drainage operation similar to that of the first embodiment described above (step S111). After the drainage operation is completed, the control unit 180 stops the fan 146 and opens the water supply valve 130 (step S112). When the water supply valve 130 is opened, deicing water is sprayed from the second water spray pipe 123 onto the back side of the ice making plate 112, and heat is applied. At this time, the surface of the ice I is melted, mainly from both end portions sandwiching the thickest part.

[0068] Then, the control unit 180 acquires the temperature outside the ice making unit 111 detected by the outside air temperature sensor 158, and acquires the threshold value TH1 by referring to the memory unit 154, and judges whether the temperature detected by the outside air temperature sensor 158 is higher than the threshold value TH1 (step S113). If the temperature detected by the outside air temperature sensor 158 is higher than the threshold value TH1 ("YES" in step S113), the control unit 180 opens the hot gas valve 150 constituting the hot gas supply unit 157 (step S114). At this time, the control unit 180 opens the hot gas valve 150 at a substantially constant opening degree. As a result, hot gas is supplied from the compressor 141 through the common refrigerant pipe 145A to the evaporation tube 144, and the evaporation tube 144 can be heated. When the evaporation tube 144 is heated, heat is applied to the back side of the ice making plate 112 that contacts the evaporation tube 144. At this time, the surface of the ice I, whose cross section is approximately crescent-shaped, melts around the thickest part. In this manner, the ice-making plate 112 is heated by the deicing water and hot gas, whereby the surface of the ice I melts and a water film is produced, facilitating the de-icing of the ice I from the ice-making surface 112A.

[0069] Here, since the hot gas flows from the inlet end to the outlet end of the evaporation tube 144, the upper part of the ice-making plate 112 is heated by the evaporation tube 144 before the lower part. Similarly, since the deicing water flows down from the second water spray pipe 123 arranged on the upper side of the ice-making plate 112, the upper part of the ice-making plate 112 is heated by the deicing water before the lower part. For this reason, if the deicing water supply unit continues to supply deicing water to the ice-making plate 112 and heat is continuously applied to the ice I attached to the upper part of the ice-making plate 112 to which heat is applied first, heat continues to be applied to the ice I until the ice I is completely deiced. For this reason, the ice I attached to the upper part of the ice-making plate 112 melts more than necessary, which may deteriorate the energy-saving performance.

[0070] In response to this, the control unit 180 judges whether the time elapsed since the hot gas valve 150 was opened has passed a predetermined time T1 (for example, 5 seconds) (step S115), and closes the hot gas valve 150 if the time has passed (step S116). After that, the control unit 180 judges whether the time elapsed since the hot gas valve 150 was closed has passed a predetermined time T2 (for example, 10 seconds) (step S117), and if the time has passed, opens the hot gas valve 150 again (step S118). At this time, the control unit 180 opens the hot gas valve 150 at a substantially constant opening degree. In other words, when the temperature detected by the outside air temperature sensor 158 is higher than the threshold value TH1, the control unit 180 controls the deicing operation so as to temporarily halt the supply of hot gas by the hot gas supply unit 157. In this way, if sufficient heat is applied to the upper part of ice-making plate 112 to which heat is applied first during the period from when hot gas supply unit 157 starts to temporarily stop (between steps S114 and S116), the surface of ice I attached to the upper part of ice-making plate 112 can be melted and de-iced while hot gas supply unit 157 is temporarily stopped (between steps S116 and S118). This prevents the ice I that is de-iced first from being given more heat than necessary, making it difficult for the ice I to melt more than necessary. In this way, when hot gas supply unit 157 resumes supply of hot gas (step S118) after waiting for the ice I attached to the upper part of ice-making plate 112 during the temporary stop period to be de-iced, heat from the hot gas is efficiently applied to the lower part of ice-making plate 112 to which the remaining ice I is attached. This allows the remaining ice to be efficiently de-iced. As described above, the amount of heat is efficiently imparted to the ice making plates 112, which is favorable for improving energy saving performance.

[0071] Moreover, the control unit 180 controls the deicing operation so that the predetermined time T2 (e.g., 10 seconds) during which the deicing operation is paused is longer than the predetermined time T1 (e.g., 5 seconds) from when the hot gas valve 150 is opened and the supply of hot gas to the evaporation tube 144 is started to be paused. In this way, the predetermined time T1 during which the supply of hot gas by the hot gas supply unit 157 is paused is sufficiently secured, so that the surface of the ice I attached to the upper part of the ice-making plate 112 to which heat is applied first can be sufficiently melted during the pause period, and the ice I is more likely to be deiced. Therefore, the heat applied after the hot gas valve 150 is opened again and the supply of hot gas to the evaporation tube 144 is resumed is more likely to be used to deicing the ice I attached to the lower part of the ice-making plate 112. This increases the certainty that the heat is efficiently applied to the ice-making plate 112, which is more suitable for improving energy-saving performance.

[0072] In addition, in the above-mentioned step S113, when the detected temperature of the outside air temperature sensor 158 is lower than the threshold value TH1 ("NO" in step S113), the control unit 180 proceeds to step S118 and opens the hot gas valve 150. At this time, the control unit 180 opens the hot gas valve 150 at a substantially constant opening degree.

[0073] As the de-icing water that flows down the back surface of ice-making plate 112 falls into water tank 113, the water level in water tank 113 rises, and when the water level eventually reaches the operation start water level that is lower than overflow water level L3 ("YES" in step S119), control unit 180 closes water supply valve 130 to stop water supply (step S120). After that, control unit 180 acquires the temperature detected by ice-making unit temperature sensor 116 and acquires a predetermined temperature C1 (e.g., 9°C) that serves as a judgment criterion by referring to memory unit 154, and judges whether the temperature detected by ice-making unit temperature sensor 116 is higher than the predetermined temperature C1 (step S121). If the temperature detected by ice-making unit temperature sensor 116 is higher than the predetermined temperature C1 ("YES" in step S121), control unit 180 judges that all ice I on ice-making surface 112A has been de-iced, and stops the de-icing operation. Then, it transitions to ice-making operation.

[0074] As described above, according to this embodiment, the system includes compressor 141 for compressing the refrigerant, condenser 142 for cooling and condensing the refrigerant from compressor 141, evaporation tube (evaporator) 144 arranged in ice making unit 111 for evaporating the refrigerant from condenser 142 to cool ice making unit 111, and hot gas supply unit 157 for supplying the refrigerant from compressor 141 as hot gas to evaporation tube 144. Hot gas supply unit 157 constitutes deicing unit 160, and control unit 180 controls the deicing operation of hot gas supply unit 157 so that the amount of hot gas supplied by hot gas supply unit 157 is reduced when the air temperature detected by outside air temperature sensor 158 is higher than threshold value TH1, compared to when the air temperature is lower than threshold value TH1. In this way, the refrigerant compressed by compressor 141 is cooled and condensed by condenser 142, and then evaporated by evaporation tube 144 to remove heat from ice making unit 111 and cool ice making unit 111. As a result, ice I is produced in ice-making unit 111. When deicing operation is performed, the refrigerant from compressor 141 is supplied as hot gas to evaporator tube 144 by hot gas supply unit 157, so that heat is imparted to ice-making unit 111, and the surface of ice I is melted by the heat, so that ice is deiced. The temperature of this hot gas tends to change according to the air temperature outside ice-making unit 111. In response to this, when the air temperature detected by outside air temperature sensor 158 is higher than threshold value TH1, control unit 180 controls the deicing operation of hot gas supply unit 157 so that the amount of hot gas supplied is reduced compared to when the air temperature is lower than threshold value TH1. Therefore, even if the temperature of the hot gas tends to be high due to the air temperature outside, the impartment of heat to ice-making unit 111 is suppressed. As a result, it becomes difficult for ice I to melt more than necessary, and energy-saving performance is improved.

[0075] The hot gas supply unit 157 has a common refrigerant pipe 145A and a bypass pipe 149 which are hot gas supply pipes connected to the compressor 141 and the evaporation pipe 144, and a hot gas valve 150 which is interposed between the common refrigerant pipe 145A and the bypass pipe 149 which are hot gas supply pipes, and the control unit 180 controls the deicing operation of the hot gas supply unit 157 so that the opening time of the hot gas valve 150 is shortened when the air temperature detected by the outside air temperature sensor 158 is higher than the threshold TH1, compared to when the air temperature is lower than the threshold TH1. In this way, the hot gas supply unit 157 supplies the amount of hot gas according to the opening degree and opening time of the hot gas valve 150 to the evaporation pipe 144 through the common refrigerant pipe 145A and the bypass pipe 149 which are hot gas supply pipes. The control unit 180 adjusts the amount of hot gas supplied by adjusting the opening time of the hot gas valve 150 in accordance with the air temperature detected by the outside air temperature sensor 158. This makes it easier and more reliable to manage the amount of hot gas supplied than if the control unit were to adjust the opening degree of the hot gas valve 150 to adjust the amount of hot gas supplied.

[0076] <Embodiment 3> A third embodiment will be described with reference to Fig. 8 or Fig. 9. In this third embodiment, the processing of the control unit 280 based on the air temperature detected by the outside air temperature sensor 258 is changed from that of the first embodiment. Note that a duplicated description of the structure, action, and effect similar to those of the first embodiment will be omitted. Also, components that appear in the description of this embodiment and have the same names as those of the first embodiment will be given the same reference numerals with the suffix "2" added to their beginning.

[0077] 8, air filter 38 is attached to cover the front surface of condenser 242 according to this embodiment. Because air blown to condenser 242 by fan 246 passes through air filter 38, dust and oily stains adhere to and accumulate on air filter 38 as fan 246 operates. If air filter 38 becomes clogged as dust and oily stains accumulate on air filter 38, heat exhaust efficiency will deteriorate, heat will be more likely to build up in condenser 242, and ice-making machine 210 as a whole may become hotter and more heavily loaded.

[0078] Therefore, as shown in FIG. 8 and FIG. 9, the control unit 280 according to this embodiment is configured to make the display unit 256 report a warning when the temperature detected by the outside air temperature sensor 258 is higher than the warning reference temperature C2. This warning reference temperature C2 is stored in the memory unit 254. Specifically, while the ice making operation, the deicing operation, and the cleaning operation are being performed, the control unit 280 appropriately acquires the temperature outside the ice making unit 211 detected by the outside air temperature sensor 258, and acquires the warning reference temperature C2 by referring to the memory unit 254, and determines whether the temperature detected by the outside air temperature sensor 258 is higher than the warning reference temperature C2. When the temperature detected by the outside air temperature sensor 258 is higher than the warning reference temperature C2, the control unit 280 makes the display unit 256 display a warning screen including a message such as "Please clean the air filter." Note that when the temperature detected by the outside air temperature sensor 258 is lower than the warning reference temperature C2, the control unit 280 does not make the display unit 256 display a warning screen. The user can recognize the need to clean air filter 38 by visually checking the warning screen displayed on display unit 256. If the user is prompted to clean air filter 38, air filter 38 will be less likely to become clogged, and ice-making machine 210 as a whole will be less likely to experience high temperatures and a high load.

[0079] In particular, because outside air temperature sensor 258 is mounted on control board 281 located above condenser 242, it can appropriately detect the air temperature near condenser 242. Since control unit 280 determines whether to issue a warning based on the air temperature detected by such outside air temperature sensor 258, it can prompt the user to clean air filter 38 at an appropriate time, thereby preferably preventing ice-making machine 210 as a whole from becoming overheated and overloaded due to clogging of air filter 38. In this way, if ice-making machine 210 as a whole is prevented from becoming overheated and overloaded, electronic components of control board 281 on which outside air temperature sensor 258 is mounted are less likely to break down, and control board 281 can be maintained.

[0080] On the other hand, there are other causes of the temperature of the entire ice-making machine 210 becoming high besides clogging of the air filter 38. For example, there is poor heat dissipation due to a failure of the fan 246, or the temperature environment in which the ice-making machine 210 is installed becomes high. In anticipation of such a situation, the control unit 280 according to this embodiment emergency stops the operation of the entire ice-making machine 210 (including the ice-making unit 211 and the de-icing unit 260) when the air temperature detected by the outside air temperature sensor 258 is higher than the emergency stop reference temperature C3. This emergency stop reference temperature C3 is stored in the memory unit 254, and is set higher than the above-mentioned warning reference temperature C2. Specifically, while the ice-making operation, the de-icing operation, and the cleaning operation are being performed, the control unit 280 appropriately acquires the air temperature outside the ice-making unit 211 detected by the outside air temperature sensor 258, and acquires the emergency stop reference temperature C3 by referring to the memory unit 254, and determines whether the air temperature detected by the outside air temperature sensor 258 is higher than the emergency stop reference temperature C3. When the temperature detected by the outside air temperature sensor 258 is lower than the emergency stop reference temperature C3, the control unit 280 continues the operation of the entire ice-making machine 210, whereas when the temperature detected by the outside air temperature sensor 258 is higher than the emergency stop reference temperature C3, the control unit 280 emergency stops the operation of the entire ice-making machine 210. In this way, even if the entire ice-making machine 210 becomes abnormally hot due to poor heat dissipation caused by a failure of the fan 246 or a high temperature in the installation temperature environment of the ice-making machine 210, the operation of the entire ice-making machine 210 is immediately stopped, so that a further increase in temperature can be suppressed. This makes it possible to avoid a situation in which a breakdown or the like occurs due to an abnormal increase in temperature. In this way, if the occurrence of a high temperature in the entire ice-making machine 210 is suppressed, the electronic components of the control board 281 on which the outside air temperature sensor 258 is installed are less likely to break down, and the control board 281 can be maintained.

[0081] As described above, according to this embodiment, the device is provided with display unit (notification unit) 256 that issues a warning, and control unit 280 causes display unit 256 to issue a warning when the air temperature detected by outside air temperature sensor 258 is higher than warning reference temperature C2. In this way, when the air temperature outside ice-making unit 211 rises abnormally and becomes higher than warning reference temperature C2, control unit 280 can urge the user to take action by causing display unit 256 to issue a warning. This makes it possible to avoid a situation in which an abnormal temperature rise continues and causes a breakdown or the like.

[0082] Furthermore, when the air temperature detected by outside air temperature sensor 258 is higher than emergency stop reference temperature C3, control unit 280 emergency stops the operation of ice-making unit 211 and deicing unit 260. In this way, when the air temperature outside ice-making unit 211 rises abnormally and becomes higher than emergency stop reference temperature C3, control unit 280 can suppress a further temperature rise by emergency stopping the operation of ice-making unit and deicing unit 260. This makes it possible to avoid a situation in which a malfunction or the like occurs due to an abnormal rise in temperature.

[0083] Furthermore, the control unit 280 includes a control board 281 on which electronic components are mounted, and the outside air temperature sensor 258 is mounted on the control board 281. The electronic components mounted on the control board 281 are more susceptible to failure due to temperature rise than mechanical components. In contrast, by mounting the outside air temperature sensor 258 on the control board 281, the outside air temperature sensor 258 can detect the air temperature near the control board 281, and the control unit 280 can cause the display unit 256 to issue a warning or emergency stop the operation of the ice-making unit 211 and the de-icing unit 260 based on the air temperature near the control board 281. This makes it difficult for the electronic components to fail, and thus the control board 281 can be maintained.

[0084] <Other embodiments> The technology disclosed in this specification is not limited to the embodiments described above and illustrated in the drawings, and for example, the following embodiments are also included within the technical scope.

[0085] (1) The first and second embodiments may be combined to control the deicing operation of both the deicing water supply unit 37 and the hot gas supply unit 57, 157 constituting the deicing unit 60, 160, 260 by the control unit 80, 180, 280. That is, when the air temperature detected by the outside air temperature sensor 58, 158, 258 is higher than the threshold TH1, the control unit 80, 180, 280 may control the deicing operation of the deicing water supply unit 37 and the hot gas supply unit 57, 157 to reduce the amount of deicing water supplied by the deicing water supply unit 37 and the amount of hot gas supplied by the hot gas supply unit 57, 157, so that the amount of heat applied to the ice making unit 11, 111, 211 as a whole is reduced, compared to when the air temperature is lower than the threshold TH1.

[0086] (2) At the timing when the deicing operation is temporarily stopped and then resumed by the control unit 80, 180, 280 (steps S18, S118), not all of the ice I attached to the upper half of the ice making plate 12, 112, 212 is necessarily de-iced, and the ice I may be attached to a part of the upper half (a part closer to the lower half) of the ice making plate 12, 112, 212. Conversely, at the same timing (steps S18, S118), all of the ice I attached to the range beyond the upper half of the ice making plate 12, 112, 212 (a range including a part of the lower half) may be de-iced.

[0087] (3) The control units 80, 180, 280 may be configured to temporarily halt the deicing operation of the deicing units 60, 160, 260 multiple times during the operation.

[0088] (4) When adjusting the amount of deicing water supplied by the deicing water supply unit 37 or the amount of hot gas supplied by the hot gas supply unit 57, 157, the control unit 80, 180, 280 may continue opening the water supply valve 30, 130 or the hot gas valve 50, 150 without temporarily stopping the opening, and adjust the opening degree of the water supply valve 30, 130 or the hot gas valve 50, 150. Also, when adjusting the amount of deicing water supplied by the deicing water supply unit 37 or the amount of hot gas supplied by the hot gas supply unit 57, 157, the control unit 80, 180, 280 may temporarily stop the opening of the water supply valve 30, 130 or the hot gas valve 50, 150 and then adjust the opening degree of the water supply valve 30, 130 or the hot gas valve 50, 150.

[0089] (5) When performing deicing operation, the control units 80, 180, 280 may open either the water supply valve 30, 130 or the hot gas valve 50, 150 first, or may open the water supply valve 30, 130 and the hot gas valve 50, 150 at the same time.

[0090] (6) The control unit 80, 180, 280 may be configured to perform deicing operation on only one of the deicing water supply unit 37 and the hot gas supply unit 57, 157.

[0091] (7) The control unit 80, 180, 280 may temporarily suspend the deicing operation of the deicing unit 60, 160, 260 even when the temperature detected by the outside air temperature sensor 58, 158, 258 is lower than the threshold TH1. In this case, the control unit 80, 180, 280 may temporarily suspend the deicing operation of the deicing unit 60, 160, 260 for a longer period when the temperature detected by the outside air temperature sensor 58, 158, 258 is higher than the threshold TH1 than when the temperature detected by the outside air temperature sensor 58, 158, 258 is lower than the threshold TH1.

[0092] (8) A plurality of threshold values ​​may be set for the control unit 80, 180, 280 to determine whether the air temperature detected by the outside air temperature sensor 58, 158, 258 is high or low. In this case, the control unit 80, 180, 280 may control the deicing operation of the deicing unit 60, 160, 260 so that three or more amounts of heat are applied to the ice making unit 11, 111, 211 according to the air temperature detected by the outside air temperature sensor 58, 158, 258.

[0093] (9) It is also possible to provide heat to the ice making units 11, 111, 211 by the deicing units 60, 160, 260 other than the deicing water supply unit 37 and the hot gas supply unit 57, 157. In that case, the control units 80, 180, 280 may control the deicing operation of the deicing units 60, 160, 260 so that the amount of heat provided to the ice making units 11, 111, 211 varies depending on the air temperature detected by the outside air temperature sensors 58, 158, 258.

[0094] (10) In the third embodiment, if the display unit 256 is provided with a speaker, the control unit 280 can output a warning sound from the speaker in addition to displaying a warning image when issuing a warning based on the warning reference temperature C2. Also, the control unit 280 can output a warning sound from the speaker without displaying a warning image when issuing a warning based on the warning reference temperature C2.

[0095] (11) In the third embodiment, the control unit 280 may perform only the emergency stop based on the emergency stop reference temperature C3 without performing the emergency stop based on the emergency stop reference temperature C3. Conversely, the control unit 280 may perform only the emergency stop based on the emergency stop reference temperature C3 without performing the warning based on the warning reference temperature C2.

[0096] (12) The control box 82 housing the control board 81, 281 may be disposed in a location other than above the condenser 42, 142, 242.

[0097] (13) The outside air temperature sensor 58, 158, 258 may be mounted on a component other than the control board 81, 281. In that case, it may be located inside or outside the control box 82. In any case, the outside air temperature sensor 58, 158, 258 may be located outside the housing unit 22 (including the outer surface of the housing unit 22).

[0098] (14) The predetermined temperature C1 and the predetermined times T1 and T2 are not limited to the numerical values ​​given as examples, and can be set appropriately.

[0099] (15) The ice storage sensor 33 and the water level sensor 17 may be other types of sensors, such as a distance sensor using ultrasonic waves.

[0100] (16) The present technology is not limited to the flow-down type ice-making machine 10, 210, but can also be applied to other types of ice-making machines (e.g., auger type).

[0101] (17) The specific number and arrangement of the baffle plates 12, 112, 212 provided in the ice making section 11, 111, 211 can be changed as appropriate. [Explanation of symbols]

[0102] 10,210...Ice maker, 11,111,211...Ice making section, 12,112,212...Ice making plate (cooling section), 12A,112A...Ice making surface, 22...Storage section, 29...Water supply pipe (de-icing water supply pipe), 30,130...Water supply valve (de-icing water valve), 31...Water pipe (de-icing water supply source), 36...Ice making water supply section, 37...De-icing water supply section, 41,141...Compressor, 42,142,242...Condenser, 44,144...Evaporation pipe (evaporator), 45A,145 A...Common refrigerant pipe (hot gas supply pipe), 49,149...Bypass pipe (hot gas supply pipe), 50,150...Hot gas valve, 56,256...Display unit (alarm unit), 57,157...Hot gas supply unit, 58,158,258...Outside air temperature sensor (air temperature detection unit), 60,160,260...De-icing unit, 80,180,280...Control unit, 81,281...Control board, C2...Warning reference temperature, C3...Emergency stop reference temperature, I...Ice, TH1...Threshold value

Claims

1. an ice making unit for producing ice; a de-icing unit that applies heat to the ice-making unit to remove the ice from the ice-making unit; an air temperature detection unit that detects an air temperature outside the ice making unit; a control unit for controlling a deicing operation of the deicing unit, the control unit controlling the deicing operation of the deicing unit so that, when the air temperature detected by the air temperature detection unit is higher than a threshold value, the amount of heat applied to the ice making unit is reduced compared to when the air temperature is lower than the threshold value; A compressor that compresses a refrigerant; a condenser that cools and condenses the refrigerant from the compressor; an evaporator disposed in the ice making unit and configured to evaporate the refrigerant from the condenser to cool the ice making unit; The control unit includes a control board on which electronic components are mounted, The air temperature detection unit is installed on the control board housed in a control box disposed on the condenser.

2. The ice making machine according to claim 1, wherein the control unit controls the de-icing operation of the de-icing unit to temporarily halt the application of heat to the ice making unit when the air temperature detected by the air temperature detection unit is higher than the threshold value.

3. The ice making machine according to claim 2, wherein the control unit controls the deicing operation of the deicing unit so that the time during which the supply of heat to the ice making unit is temporarily stopped is longer than the time from when the supply of heat to the ice making unit is started to when the supply of heat to the ice making unit is temporarily stopped.

4. A hot gas supply unit that supplies the refrigerant from the compressor to the evaporator as hot gas, The hot gas supply unit constitutes the deicing unit, An ice making machine as described in any one of claims 1 to 3, wherein the control unit controls the de-icing operation of the hot gas supply unit so that the amount of hot gas supplied by the hot gas supply unit is reduced when the air temperature detected by the air temperature detection unit is higher than the threshold value compared to when the air temperature is lower than the threshold value.

5. The hot gas supply unit includes a hot gas supply pipe connected to the compressor and the evaporator, and a hot gas valve provided in the hot gas supply pipe, The ice making machine of claim 4, wherein the control unit controls the de-icing operation of the hot gas supply unit so that the opening time of the hot gas valve is shortened when the air temperature detected by the air temperature detection unit is higher than the threshold value compared to when the air temperature is lower than the threshold value.

6. A deicing water supply unit is provided to supply deicing water to the ice making unit, The deicing water supply unit constitutes the deicing unit, 6. The ice making machine according to claim 1, wherein the control unit controls the deicing operation of the deicing water supply unit so that, when the air temperature detected by the air temperature detection unit is higher than the threshold value, the amount of deicing water supplied by the deicing water supply unit is reduced compared to when the air temperature is lower than the threshold value.

7. An ice making water supply unit is provided to supply ice making water to the ice making unit, The ice making unit includes an ice making plate having an ice making surface on which the ice making water supplied by the ice making water supply unit flows, The ice making machine according to claim 6 , wherein the deicing water supply unit supplies the deicing water to a surface of the ice making plate opposite to the ice making surface, and causes the deicing water to flow down.

8. The deicing water supply unit includes a deicing water supply pipe connected to the deicing water supply source and the ice making unit, and a deicing water valve provided in the deicing water supply pipe, 8. The ice making machine according to claim 6 or claim 7, wherein the control unit controls the deicing operation of the deicing water supply unit so that the opening time of the deicing water valve is shortened when the air temperature detected by the air temperature detection unit is higher than the threshold value compared to when the air temperature is lower than the threshold value.

9. It is equipped with an alarm unit that issues a warning, The ice making machine according to claim 1 , wherein the control unit causes the notification unit to issue the warning when the air temperature detected by the air temperature detection unit is higher than a warning reference temperature.

10. The ice making machine according to any one of claims 1 to 9, wherein the control unit emergency stops operation of the ice making unit and the deicing unit when the air temperature detected by the air temperature detection unit is higher than an emergency stop reference temperature.

Images