JP7610451B2 - Food Refrigeration Equipment - Google Patents

Description

The present invention relates to a food freezing device.

As described in Patent Document 1, a food cooler used for freezing food, etc., has been known.

The food cooling cabinet described in Patent Document 1 is a blast chiller, and is equipped with a cooler connected to a cooling unit, a cooler blower for circulating the cold air that has been heat exchanged in the cooler inside the cabinet, an interior sensor that detects the interior temperature, and a core temperature sensor that detects the core temperature of the food. In this cooling cabinet, the rotation frequency of the cooler blower is controlled based on the temperature detected by the core temperature sensor.

JP 2000-249444 A

The air blast method described in Patent Document 1 can rapidly lower the temperature of food by blowing cold air at the food with great force. However, the cold air hits the food unevenly, which causes unevenness in the speed at which the food freezes. Therefore, conventional food freezing devices have the problem of making it difficult to prevent uneven freezing of food.

The present invention was made in consideration of the above problems, and its purpose is to provide a food freezing device that can prevent uneven freezing of food.

A food freezing device according to one aspect of the present invention includes a food storehouse that stores food, a cooler for cooling the inside of the food storehouse, a temperature detection unit that detects the temperature of the air in the food storehouse or the temperature of the food, an interior fan for forming a circulating air flow in the food storehouse, a food cooling fan for blowing air toward the food, and a control unit that controls the cooler, the interior fan, and the food cooling fan . The control unit switches from a standby mode in which the cooler is controlled so that the detected temperature by the temperature detection unit is maintained at a set temperature after the detected temperature reaches the set temperature, to a quick freezing mode in which the cooler is controlled so that the cooling capacity is higher than in the standby mode. In the standby mode, the control unit drives the interior fan while stopping the food cooling fan, and drives the food cooling fan in the quick freezing mode.

According to this food freezing device, in standby mode, the air temperature in the food storage unit reaches a set temperature and then the food temperature approaches the set temperature while being maintained at the set temperature, or in standby mode, the food temperature reaches a set temperature and then is maintained at the set temperature, thereby reducing unevenness in food temperature. Therefore, since the standby mode can be switched to the quick-freeze mode when the unevenness in food temperature is reduced, uneven freezing of food can be suppressed. Furthermore, by using the storage unit fan and the food cooling fan in combination, food can be cooled efficiently. Furthermore, by driving the food cooling fan in the quick-freeze mode, the cooling speed of food in the quick-freeze mode can be increased.
In the quick freezing mode, the control unit may drive the internal fan at a rotation frequency higher than that in the standby mode.
The food storage space is divided into an air-conditioned space and a food storage space by a partition, the interior fan is provided in the air-conditioned space so as to blow air from the air-conditioned space into the food storage space, and multiple food cooling fans may be provided in the food storage space.

In the above food freezing device, the set temperature may be set in the refrigeration temperature range.

With this configuration, when switching from standby mode to quick-freeze mode to freeze food, the time it takes for the food temperature to reach the freezing point from the set temperature can be shortened. This makes it possible to prevent temperature unevenness in the food from becoming too great until the food temperature reaches the freezing point.

The food freezer may further include a food plate made of metal on which the food is placed.

With this configuration, by using not only cold air circulating inside the food storage but also a metal plate, food can be cooled more efficiently and the freezing speed can be increased.

In the above food freezing device, the food plate may include a plate body having a placement surface on which the food is placed, and fins provided on the surface of the plate body opposite the placement surface.

With this configuration, the fins can increase the heat transfer area of the food plate, allowing food to be cooled more efficiently.

In the above food freezing device, the control unit may switch from the quick freezing mode to a rewarming mode based on a signal input. In the rewarming mode, the cooler may be controlled by the control unit so that the temperature of the air in the food storage unit is raised to the set temperature.

This configuration allows the food storage room to be easily and quickly reheated in preparation for the next food freezing process.

As is clear from the above explanation, the present invention provides a food freezing device that can reduce uneven freezing of food.

1 is a diagram showing a schematic configuration of a food freezing device according to a first embodiment of the present invention; 1 is a diagram showing a schematic configuration of a food plate in accordance with a first embodiment of the present invention; FIG. 5 is a graph for explaining a standby mode and a quick-freezing mode executed by the food freezing apparatus according to the first embodiment of the present invention. 4 is a flowchart for explaining a standby mode and a quick-freezing mode executed by the food freezing apparatus according to the first embodiment of the present invention. 10 is a flowchart for explaining an internal temperature control in a food freezing apparatus according to a second embodiment of the present invention. 10 is a flowchart for explaining an internal temperature control in a food freezing apparatus according to a third embodiment of the present invention.

The following describes in detail an embodiment of the present invention with reference to the drawings.

(Embodiment 1)
First, the configuration of a food freezing device 1 according to a first embodiment of the present invention will be described with reference to Figures 1 and 2. The food freezing device 1 according to this embodiment is a device for quickly freezing food F1. The type of food F1 is not particularly limited, but it may be hot food immediately after cooking, such as curry or stew. As shown in Figure 1, the food freezing device 1 mainly includes a food storage 10, a food storage rack 20, a cooler 30, a heater 31, a humidifier 32, an internal fan 40, a plurality of food cooling fans 41, an internal temperature detector T1, a food temperature detector T2, and a controller 50.

The food storage facility 10 stores food F1 and includes a storage body 11 and a door 12. As shown in FIG. 1, the space inside the storage body 11 is divided into a food storage space 11A and an air-conditioned space 11B by a partition plate 13 that extends vertically. The opening of the food storage space 11A can be opened and closed by the door 12.

The food storage rack 20 is arranged in the food storage space 11A. The food storage rack 20 includes multiple shelves 21 arranged vertically at intervals. Food F1 is placed on the shelves 21.

The cooler 30 is for cooling the inside of the food storehouse 10. Specifically, the cooler 30 is an evaporator in a refrigerator that includes a vapor compression refrigeration cycle, and is disposed in the air-conditioned space 11B. The cooler 30 cools the air circulating inside the food storehouse 10 through heat exchange with a refrigerant.

The heater 31 is a heater for heating the air circulating inside the food storehouse 10. In this embodiment, as shown in FIG. 1, the heater 31 is disposed downstream of the cooler 30 in the air-conditioned space 11B. Note that in this specification, upstream and downstream are based on the direction in which air circulates inside the food storehouse 10.

The humidifier 32 is for humidifying the air circulating within the food storehouse 10, and is located upstream of the cooler 30 (on the bottom surface of the storehouse body 11) in the air-conditioned space 11B. The humidifier 32 in this embodiment is of the bread tray type, and includes an evaporation dish in which humidification water is stored, and a humidification heater (not shown) located within the evaporation dish. By providing the humidifier 32, it is possible to prevent the food F1 from drying out during the freezing process. However, the humidifier 32 is not an essential component of the food freezing device of the present invention, and may be omitted.

The interior fan 40 is driven by a motor 40A to create a circulating air flow within the food storehouse 10. By driving the interior fan 40, a circulating air flow is created within the food storehouse 10, flowing downward through the food storage space 11A and upward through the air-conditioned space 11B. As shown in FIG. 1, an intake port is formed between the bottom surface of the main body 11 and the lower end of the partition plate 13 to draw air from the food storage space 11A to the air-conditioned space 11B. An air outlet is formed between the top surface of the main body 11 and the upper end of the partition plate 13 to blow air from the air-conditioned space 11B to the food storage space 11A. The interior fan 40 is positioned facing the air outlet.

The food cooling fan 41 is for blowing air towards the food F1. As shown in FIG. 1, one food cooling fan 41 is provided on each of the multiple shelves 21. The food cooling fan 41 is provided on the rear end of the shelf 21 (the end opposite the door 12) and blows air towards the inner surface of the door 12.

The internal temperature detector T1 is a sensor that detects the temperature of the air inside the food storehouse 10. In this embodiment, as shown in FIG. 1, the internal temperature detector T1 is disposed near the air outlet in the food storage space 11A. The detection signal of the internal temperature detector T1 is transmitted to the control unit 50. Note that the position of the internal temperature detector T1 is not limited thereto, and it may be disposed near the air inlet in the food storage space 11A, or may be disposed near both the air outlet and the air inlet. Although not shown, a humidity detector is also disposed inside the food storehouse 10.

The food temperature detection unit T2 is a sensor that directly detects the temperature of the food F1. The detection signal of the food temperature detection unit T2 is sent to the control unit 50. Note that although only one food temperature detection unit T2 is shown in FIG. 1, multiple food temperature detection units T2 may be provided. In this case, the temperatures of multiple parts of the food F1 or multiple foods F1 are detected by the multiple food temperature detection units T2, respectively, and the temperature uniformity of the entire food F1 or multiple foods F1 can be confirmed based on the temperature difference between them.

The food freezing device 1 further includes a food plate 60 (FIG. 2). The food plate 60, on which the food F1 is placed, is made of a metal such as aluminum or stainless steel. The food plate 60 is placed on the shelf 21 (FIG. 1) when in use, and the shelf 21 is provided with a support portion (not shown) for supporting the food plate 60.

2, the food plate 60 includes a plate body 61 and a plurality of heat exchange fins 62. The plate body 61 is, for example, a rectangular plate in plan view, and has an upper surface 61A (mounting surface) on which the food F1 is placed, and a lower surface 61B facing the opposite side to the upper surface 61A. The heat exchange fins 62 are rectangular plates in plan view with a width (length in the vertical direction of the paper in FIG. 2) smaller than the width of the plate body 61 (length in the horizontal direction of the paper in FIG. 2), and are provided on the lower surface 61B of the plate body 61. More specifically, as shown in FIG. 2, the heat exchange fins 62 are attached perpendicularly to the plate body 61, and the longitudinal direction of the heat exchange fins 62 is parallel to the longitudinal direction of the plate body 61. The plurality of heat exchange fins 62 are arranged at intervals from each other in the short direction of the plate body 61, and are parallel to each other. The heat exchange fins are not limited to parallel fins, and may be, for example, pin-type fins or offset-type fins.

The food plate 60 is placed on the shelf 21 so that the longitudinal direction of the plate body 61 and the heat exchange fins 62 coincides with the direction of air blown by the food cooling fan 41 (Fig. 1). Therefore, the air blown out from the food cooling fan 41 flows through the gaps between adjacent heat exchange fins 62 (Fig. 2) along the longitudinal direction of the heat exchange fins 62.

The control unit 50 is a computer that controls various operations of the food freezing device 1, and is composed of a control panel located outside the food storehouse 10. Specifically, the control unit 50 controls the cooling capacity of the cooler 30, the heating capacity of the heater 31, the amount of humidification by the humidifier 32, and the drive (on/off and rotation frequency) of the internal fan 40 and the food cooling fan 41.

The control unit 50 switches from a standby mode in which the cooler 30 is controlled so that the temperature detected by the storage temperature detection unit T1 reaches a first set temperature (set temperature) that is higher than the freezing point of the food F1, and then the detected temperature is maintained at the first set temperature, to a quick freezing mode in which the cooler 30 is controlled so that the cooling capacity is higher than in the standby mode. This control will be explained below with reference to Figures 3 and 4. Figure 3 is a graph showing the time change in air temperature (solid line) and the time change in food temperature (dashed line) inside the food storage unit 10, with the horizontal axis indicating time and the vertical axis indicating temperature. Figure 4 is a flowchart showing the contents of the above control.

Before the freezing process begins, the inside of the food storehouse 10 is at room temperature, and in this state, food F1 is placed inside the food storehouse 10 (step S10 in Figure 4). Specifically, the door 12 is opened, the food plate 60 (Figure 2) on which the food F1 is placed is placed in a fixed position on the shelf 21 (Figure 1), and then the door 12 is closed. This causes the food F1 to be stored in the food storage space 11A.

Next, cooling of the food storehouse 10 is started (step S20). In this step S20, the control unit 50 controls the cooling capacity of the cooler 30 so that the air temperature in the food storehouse 10 (the temperature detected by the storehouse temperature detection unit T1) approaches the first set temperature from room temperature. Specifically, the control unit 50 feedback controls the freezer based on the difference between the temperature detected by the storehouse temperature detection unit T1 and the first set temperature. During this time, the surface temperature of the food F1 is also detected by the food temperature detection unit T2. In step S20, the storehouse fan 40 is driven by the control unit 50, while the food cooling fan 41 is stopped. In addition, the humidifier 32 may be operated during step S20 to prevent the food F1 from drying out.

Here, the "first set temperature" is a temperature higher than the freezing point of food F1, and is input to the control unit 50. The "freezing point" is the temperature at which food F1 begins to freeze, and differs depending on the type of food F1. For example, the freezing point of seafood is -1.3°C, the freezing point of beef is -1.7°C, the freezing point of tomatoes is -1°C, the freezing point of apples is -2°C, and the freezing point of cherries is -4°C. In this embodiment, the first set temperature is set in the refrigeration temperature zone, and is set to 5°C or lower (for example, 3°C).

The shaded area in the graph of Figure 3 is called the "maximum ice crystallization temperature zone," which is the temperature zone where ice forms during the freezing process of food F1. The maximum ice crystallization temperature zone is, for example, in the range of -1°C to -5°C, and its upper limit corresponds to the freezing point of food F1.

When the air temperature inside the food storehouse 10 reaches the first set temperature (YES in step S30 in FIG. 4), the control unit 50 controls the cooler 30 so that the air temperature is maintained at the first set temperature (step S40). As shown in FIG. 3, at time t1 when the air temperature inside the food storehouse 10 reaches the first set temperature, the food temperature has not yet reached the first set temperature, and at a later time t2, the food temperature reaches the first set temperature, lagging behind the storehouse temperature. The period from when cooling inside the food storehouse 10 begins until the food temperature reaches the first set temperature corresponds to standby mode (times t0 to t2 in FIG. 3).

When the food temperature reaches the first set temperature (YES in step S50 in FIG. 4), the control unit 50 switches the operation mode of the food freezing device 1 from standby mode to quick-freeze mode. In quick-freeze mode, the freezer is feedback-controlled based on the difference between the second set temperature and the temperature detected by the internal temperature detection unit T1 (step S60), and the control unit 50 drives the food cooling fan 41 (step S70). The second set temperature is a temperature lower than the first set temperature and the lower limit temperature of the maximum ice crystal temperature zone, and differs depending on the type of food F1. In this embodiment, the rotation frequency of the internal fan 40 in quick-freeze mode is higher than the rotation frequency of the internal fan 40 in standby mode.

In step S60, a lower set temperature is used compared to step S20 during standby mode, and the cooling capacity of the cooler 30 is increased. As a result, as shown in FIG. 3, both the air temperature and food temperature in the food storehouse 10 drop more steeply compared to standby mode.

This allows the cooling rate in the maximum ice crystal temperature zone to be increased. If the cooling rate in the maximum ice crystal temperature zone is slow, the ice crystals formed during the freezing process will become large, which may result in the cells of the food F1 being destroyed and impairing the taste when thawed. In contrast, by increasing the cooling rate in the maximum ice crystal temperature zone, the occurrence of the above-mentioned problems can be prevented. In step S60, the food F1 is cooled by the cold air circulating within the food storehouse 10 and the food plate 60 (Figure 2), and the food F1 is flash-frozen.

When the air temperature inside the food storehouse 10 reaches the second set temperature (YES in step S80 in FIG. 4), the control unit 50 controls the cooler 30 so that the air temperature is maintained at the second set temperature (step S90). The frozen food F1 is then removed from the food storehouse 10 (step S100) and stored in a freezer or the like.

As described above, according to the food freezing device 1 of this embodiment, while the air temperature in the food storehouse 10 reaches the first set temperature in standby mode and is maintained at the first set temperature, the food temperature is brought closer to the first set temperature, and temperature unevenness of the food F1 at temperatures near the freezing point can be reduced. Therefore, when the temperature unevenness of the food F1 at temperatures near the freezing point is reduced, the standby mode can be switched to the quick freezing mode, and the food F1 can be quickly frozen while suppressing cooling unevenness in the maximum ice crystal temperature range, thereby suppressing freezing unevenness of the food F1. Note that "temperature unevenness of the food F1" includes temperature unevenness within the same food F1 (for example, temperature unevenness due to the difference between the surface temperature of the food F1 and the internal temperature of the food F1) and temperature unevenness between multiple foods F1.

(Embodiment 2)
Next, a food freezing apparatus according to a second embodiment of the present invention will be described with reference to Fig. 5. The food freezing apparatus according to the second embodiment basically has the same configuration and effect as the first embodiment, but differs in that it does not have a food temperature detection unit T2. Only the differences from the first embodiment will be described below.

Figure 5 shows the control flow of the freezing process of food F1 in embodiment 2. The control flow in Figure 5 differs from the control flow in Figure 4 only in step S51. That is, steps S11 to S41 and S61 to S101 in Figure 5 are the same as steps S10 to S40 and S60 to S100 in Figure 4.

In the second embodiment, after the air temperature in the food storehouse 10 reaches the first set temperature (YES in step S31 in FIG. 5), the air temperature is maintained at the first set temperature for a predetermined set time. This set time is the time from when the air temperature in the food storehouse 10 reaches the first set temperature until the food temperature reaches the first set temperature, which has been confirmed in advance in a preliminary experiment or the like, and is input to the control unit 50.

In step S51, a timer built into the control unit 50 counts the time that has elapsed since the air temperature inside the food storehouse 10 reached the first set temperature, and determines whether the elapsed time has reached the set time. After the set time has elapsed (YES in step S51), the control unit 50 switches the operation mode of the food freezing device from standby mode to quick freezing mode, as in the first embodiment.

According to this embodiment, even in a device configuration in which the food temperature detection unit T2 is omitted, the temperature of the food F1 can be stabilized in standby mode and then switched to quick-freeze mode. This makes it possible to further simplify the configuration of the food freezer.

(Embodiment 3)
Next, a food freezing apparatus according to a third embodiment of the present invention will be described with reference to Fig. 6. The food freezing apparatus according to the third embodiment basically has the same configuration and produces the same effects as the first embodiment, but differs in that the control unit 50 further executes a rewarming mode. Only the differences from the first embodiment will be described below.

Figure 6 shows the control flow of the freezing process of food F1 in embodiment 3. The control flow in Figure 6 differs from the control flow in Figure 4 in that it further includes steps S110 and S120. That is, steps S12 to S102 in Figure 6 are the same as steps S10 to S100 in Figure 4.

When a rewarming signal is input to the control unit 50 after the frozen food F1 is removed from the food storehouse 10 in step S102 (YES in step S110), the control unit 50 switches the operation mode of the food freezing device from quick freezing mode to rewarming mode based on the signal input (step S120). For example, the control unit 50 may receive the rewarming signal input to an input unit (not shown) such as a touch panel, or the rewarming signal may be input to the control unit 50 by detecting that the door 12 has been opened and then closed in step S102. In the rewarming mode, the control unit 50 controls the cooling capacity of the cooler 30 so that the temperature of the air in the food storehouse 10 rises to the first set temperature. At this time, the control unit 50 may operate the heater 31.

After the food storage 10 has been reheated in this manner, the next food F1 is placed in the food storage 10 and the freezing process is carried out again. With the food freezing device according to this embodiment, the food storage 10 can be easily reheated when continuously freezing food F1.

(Embodiment 4)
Next, a food freezing apparatus according to a fourth embodiment of the present invention will be described. The food freezing apparatus according to the fourth embodiment is basically the same as the first and third embodiments, but differs in that a food temperature detector T2 is used instead of the internal temperature detector T1 in controlling the cooler 30.

In this embodiment, the control unit 50 controls the cooler 30 in standby mode so that the temperature detected by the food temperature detection unit T2 is maintained at the first set temperature after the temperature reaches the first set temperature. That is, in the control flow of FIG. 4, instead of steps S30 to S50, it determines whether the food temperature has reached the first set temperature, then maintains the food temperature at the first set temperature for a predetermined time, and then switches to quick freezing mode. In this case, the air temperature in the food storehouse 10 may become negative. For this reason, the control unit 50 controls the cooler 30 in standby mode based on the temperature detected by the food temperature detection unit T2, and controls the cooler 30 so that the air temperature in the food storehouse 10 is higher than the freezing point.

In addition, in this embodiment, the control unit 50 may control the cooler 30 in the quick freezing mode so that the temperature detected by the food temperature detection unit T2 is maintained at the second set temperature. That is, in step S80 of the control flow in FIG. 4, it may be determined whether the food temperature has reached the second set temperature, and in step S90, the food temperature may be maintained at the second set temperature.

(Other embodiments)
Here, other embodiments of the present invention will be described.

The food cooling fan 41 may be omitted. In this case, the risk of equipment failure can be reduced.

The heat exchange fins on the food plate 60 may be columnar. A heat pipe (not shown) may be provided inside the food plate 60 to improve the cooling capacity of the food F1. The food plate 60 may also be omitted, and the food F1 may be placed directly on the shelf 21.

The food temperature detection unit T2 may detect the surface temperature of the food F1, or may detect the central temperature (core temperature) of the food F1.

The food cooling fan 41 may be driven during standby mode. Also, the food cooling fan 41 may be stopped during quick-freeze mode.

When switching from standby mode to quick-freeze mode, the rotation frequency of the interior fan 40 may be kept constant.

The quick-freeze mode is not limited to being executed immediately after the food temperature reaches the first set temperature, and a waiting time may be provided between the time when the food temperature reaches the first set temperature and the time when the quick-freeze mode is executed. In this case, the quick-freeze mode can be executed after the overall temperature of the food F1 is further homogenized.

The food storage room 10 is not limited to the rear-air outlet type shown in FIG. 1, but may be a ceiling-air outlet type.

The determination in step S51 (FIG. 5) in embodiment 2 may be applied to embodiment 1 or embodiment 3. In this case, food temperature detection unit T2 is not used for operational control, but is used to monitor the temperature of food F1.

The embodiments disclosed herein are illustrative in all respects and should not be construed as limiting. The scope of the present invention is indicated by the claims rather than the above description, and is intended to include all modifications within the meaning and scope of the claims.

REFERENCE SIGNS LIST 1 Food freezing device 10 Food storage 30 Cooler 40 Storage fan 41 Food cooling fan 50 Control unit 60 Food plate 61 Plate body 61A Top surface (mounting surface)
62 Heat exchange fin (fin)
F1 Food T1 Internal temperature detector (temperature detector)
T2 Food temperature detector (temperature detector)

Claims (7)

a food storage facility for storing food;
A cooler for cooling the inside of the food storage;
A temperature detection unit that detects the temperature of the air in the food storage or the temperature of the food;
An interior fan for forming a circulating air flow within the food storage;
a food cooling fan for blowing air toward the food;
A control unit that controls the cooler , the interior fan, and the food cooling fan ,
the control unit switches from a standby mode in which the cooler is controlled so that the detected temperature by the temperature detection unit reaches a set temperature and then the detected temperature is maintained at the set temperature to a quick freezing mode in which the cooler is controlled so that the cooling capacity is higher than that of the standby mode ;
The control unit drives the interior fan while stopping the food cooling fan in the standby mode, and drives the food cooling fan in the quick freezing mode . The food freezing apparatus according to claim 1 , wherein the control unit drives the internal fan at a rotation frequency in the quick freezing mode at a speed higher than that in the standby mode. The food storage space is divided into an air-conditioned space and a food storage space by a partition plate,
The interior fan is provided in the air-conditioning space so as to blow air in the air-conditioning space into the food storage space,
3. The food freezing apparatus according to claim 1, wherein a plurality of said food cooling fans are provided in said food accommodation space. The food freezing apparatus according to claim 1 , wherein the preset temperature is set in a refrigeration temperature range. The food freezing apparatus according to claim 1 , further comprising a food plate made of metal on which the food is placed. The food plate comprises:
A plate body having a placement surface on which the food is placed;
The food freezing apparatus according to claim 5 , further comprising: a fin provided on a surface of the plate body opposite to the placing surface. The control unit switches from the quick freezing mode to a rewarming mode based on a signal input,
The food freezing apparatus according to any one of claims 1 to 6, wherein in the reheating mode, the cooler is controlled by the control unit so that the temperature of the air in the food storage room is raised to the set temperature.

Images